blob: 5ff09de6c48fcbec5a9b954fa284c02617204de4 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2013-2017 ARM Limited, All Rights Reserved.
* Author: Marc Zyngier <marc.zyngier@arm.com>
*/
#include <linux/acpi.h>
#include <linux/acpi_iort.h>
#include <linux/bitfield.h>
#include <linux/bitmap.h>
#include <linux/cpu.h>
#include <linux/crash_dump.h>
#include <linux/delay.h>
#include <linux/dma-iommu.h>
#include <linux/efi.h>
#include <linux/interrupt.h>
#include <linux/iopoll.h>
#include <linux/irqdomain.h>
#include <linux/list.h>
#include <linux/log2.h>
#include <linux/memblock.h>
#include <linux/mm.h>
#include <linux/msi.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/of_pci.h>
#include <linux/of_platform.h>
#include <linux/percpu.h>
#include <linux/slab.h>
#include <linux/syscore_ops.h>
#include <linux/irqchip.h>
#include <linux/irqchip/arm-gic-v3.h>
#include <linux/irqchip/arm-gic-v4.h>
#include <asm/cputype.h>
#include <asm/exception.h>
#include "irq-gic-common.h"
#define ITS_FLAGS_CMDQ_NEEDS_FLUSHING (1ULL << 0)
#define ITS_FLAGS_WORKAROUND_CAVIUM_22375 (1ULL << 1)
#define ITS_FLAGS_WORKAROUND_CAVIUM_23144 (1ULL << 2)
#define RDIST_FLAGS_PROPBASE_NEEDS_FLUSHING (1 << 0)
#define RDIST_FLAGS_RD_TABLES_PREALLOCATED (1 << 1)
#define RD_LOCAL_LPI_ENABLED BIT(0)
#define RD_LOCAL_PENDTABLE_PREALLOCATED BIT(1)
#define RD_LOCAL_MEMRESERVE_DONE BIT(2)
static u32 lpi_id_bits;
/*
* We allocate memory for PROPBASE to cover 2 ^ lpi_id_bits LPIs to
* deal with (one configuration byte per interrupt). PENDBASE has to
* be 64kB aligned (one bit per LPI, plus 8192 bits for SPI/PPI/SGI).
*/
#define LPI_NRBITS lpi_id_bits
#define LPI_PROPBASE_SZ ALIGN(BIT(LPI_NRBITS), SZ_64K)
#define LPI_PENDBASE_SZ ALIGN(BIT(LPI_NRBITS) / 8, SZ_64K)
#define LPI_PROP_DEFAULT_PRIO GICD_INT_DEF_PRI
/*
* Collection structure - just an ID, and a redistributor address to
* ping. We use one per CPU as a bag of interrupts assigned to this
* CPU.
*/
struct its_collection {
u64 target_address;
u16 col_id;
};
/*
* The ITS_BASER structure - contains memory information, cached
* value of BASER register configuration and ITS page size.
*/
struct its_baser {
void *base;
u64 val;
u32 order;
u32 psz;
};
struct its_device;
/*
* The ITS structure - contains most of the infrastructure, with the
* top-level MSI domain, the command queue, the collections, and the
* list of devices writing to it.
*
* dev_alloc_lock has to be taken for device allocations, while the
* spinlock must be taken to parse data structures such as the device
* list.
*/
struct its_node {
raw_spinlock_t lock;
struct mutex dev_alloc_lock;
struct list_head entry;
void __iomem *base;
void __iomem *sgir_base;
phys_addr_t phys_base;
struct its_cmd_block *cmd_base;
struct its_cmd_block *cmd_write;
struct its_baser tables[GITS_BASER_NR_REGS];
struct its_collection *collections;
struct fwnode_handle *fwnode_handle;
u64 (*get_msi_base)(struct its_device *its_dev);
u64 typer;
u64 cbaser_save;
u32 ctlr_save;
u32 mpidr;
struct list_head its_device_list;
u64 flags;
unsigned long list_nr;
int numa_node;
unsigned int msi_domain_flags;
u32 pre_its_base; /* for Socionext Synquacer */
int vlpi_redist_offset;
};
#define is_v4(its) (!!((its)->typer & GITS_TYPER_VLPIS))
#define is_v4_1(its) (!!((its)->typer & GITS_TYPER_VMAPP))
#define device_ids(its) (FIELD_GET(GITS_TYPER_DEVBITS, (its)->typer) + 1)
#define ITS_ITT_ALIGN SZ_256
/* The maximum number of VPEID bits supported by VLPI commands */
#define ITS_MAX_VPEID_BITS \
({ \
int nvpeid = 16; \
if (gic_rdists->has_rvpeid && \
gic_rdists->gicd_typer2 & GICD_TYPER2_VIL) \
nvpeid = 1 + (gic_rdists->gicd_typer2 & \
GICD_TYPER2_VID); \
\
nvpeid; \
})
#define ITS_MAX_VPEID (1 << (ITS_MAX_VPEID_BITS))
/* Convert page order to size in bytes */
#define PAGE_ORDER_TO_SIZE(o) (PAGE_SIZE << (o))
struct event_lpi_map {
unsigned long *lpi_map;
u16 *col_map;
irq_hw_number_t lpi_base;
int nr_lpis;
raw_spinlock_t vlpi_lock;
struct its_vm *vm;
struct its_vlpi_map *vlpi_maps;
int nr_vlpis;
};
/*
* The ITS view of a device - belongs to an ITS, owns an interrupt
* translation table, and a list of interrupts. If it some of its
* LPIs are injected into a guest (GICv4), the event_map.vm field
* indicates which one.
*/
struct its_device {
struct list_head entry;
struct its_node *its;
struct event_lpi_map event_map;
void *itt;
u32 nr_ites;
u32 device_id;
bool shared;
};
static struct {
raw_spinlock_t lock;
struct its_device *dev;
struct its_vpe **vpes;
int next_victim;
} vpe_proxy;
struct cpu_lpi_count {
atomic_t managed;
atomic_t unmanaged;
};
static DEFINE_PER_CPU(struct cpu_lpi_count, cpu_lpi_count);
static LIST_HEAD(its_nodes);
static DEFINE_RAW_SPINLOCK(its_lock);
static struct rdists *gic_rdists;
static struct irq_domain *its_parent;
static unsigned long its_list_map;
static u16 vmovp_seq_num;
static DEFINE_RAW_SPINLOCK(vmovp_lock);
static DEFINE_IDA(its_vpeid_ida);
#define gic_data_rdist() (raw_cpu_ptr(gic_rdists->rdist))
#define gic_data_rdist_cpu(cpu) (per_cpu_ptr(gic_rdists->rdist, cpu))
#define gic_data_rdist_rd_base() (gic_data_rdist()->rd_base)
#define gic_data_rdist_vlpi_base() (gic_data_rdist_rd_base() + SZ_128K)
/*
* Skip ITSs that have no vLPIs mapped, unless we're on GICv4.1, as we
* always have vSGIs mapped.
*/
static bool require_its_list_vmovp(struct its_vm *vm, struct its_node *its)
{
return (gic_rdists->has_rvpeid || vm->vlpi_count[its->list_nr]);
}
static u16 get_its_list(struct its_vm *vm)
{
struct its_node *its;
unsigned long its_list = 0;
list_for_each_entry(its, &its_nodes, entry) {
if (!is_v4(its))
continue;
if (require_its_list_vmovp(vm, its))
__set_bit(its->list_nr, &its_list);
}
return (u16)its_list;
}
static inline u32 its_get_event_id(struct irq_data *d)
{
struct its_device *its_dev = irq_data_get_irq_chip_data(d);
return d->hwirq - its_dev->event_map.lpi_base;
}
static struct its_collection *dev_event_to_col(struct its_device *its_dev,
u32 event)
{
struct its_node *its = its_dev->its;
return its->collections + its_dev->event_map.col_map[event];
}
static struct its_vlpi_map *dev_event_to_vlpi_map(struct its_device *its_dev,
u32 event)
{
if (WARN_ON_ONCE(event >= its_dev->event_map.nr_lpis))
return NULL;
return &its_dev->event_map.vlpi_maps[event];
}
static struct its_vlpi_map *get_vlpi_map(struct irq_data *d)
{
if (irqd_is_forwarded_to_vcpu(d)) {
struct its_device *its_dev = irq_data_get_irq_chip_data(d);
u32 event = its_get_event_id(d);
return dev_event_to_vlpi_map(its_dev, event);
}
return NULL;
}
static int vpe_to_cpuid_lock(struct its_vpe *vpe, unsigned long *flags)
{
raw_spin_lock_irqsave(&vpe->vpe_lock, *flags);
return vpe->col_idx;
}
static void vpe_to_cpuid_unlock(struct its_vpe *vpe, unsigned long flags)
{
raw_spin_unlock_irqrestore(&vpe->vpe_lock, flags);
}
static int irq_to_cpuid_lock(struct irq_data *d, unsigned long *flags)
{
struct its_vlpi_map *map = get_vlpi_map(d);
int cpu;
if (map) {
cpu = vpe_to_cpuid_lock(map->vpe, flags);
} else {
/* Physical LPIs are already locked via the irq_desc lock */
struct its_device *its_dev = irq_data_get_irq_chip_data(d);
cpu = its_dev->event_map.col_map[its_get_event_id(d)];
/* Keep GCC quiet... */
*flags = 0;
}
return cpu;
}
static void irq_to_cpuid_unlock(struct irq_data *d, unsigned long flags)
{
struct its_vlpi_map *map = get_vlpi_map(d);
if (map)
vpe_to_cpuid_unlock(map->vpe, flags);
}
static struct its_collection *valid_col(struct its_collection *col)
{
if (WARN_ON_ONCE(col->target_address & GENMASK_ULL(15, 0)))
return NULL;
return col;
}
static struct its_vpe *valid_vpe(struct its_node *its, struct its_vpe *vpe)
{
if (valid_col(its->collections + vpe->col_idx))
return vpe;
return NULL;
}
/*
* ITS command descriptors - parameters to be encoded in a command
* block.
*/
struct its_cmd_desc {
union {
struct {
struct its_device *dev;
u32 event_id;
} its_inv_cmd;
struct {
struct its_device *dev;
u32 event_id;
} its_clear_cmd;
struct {
struct its_device *dev;
u32 event_id;
} its_int_cmd;
struct {
struct its_device *dev;
int valid;
} its_mapd_cmd;
struct {
struct its_collection *col;
int valid;
} its_mapc_cmd;
struct {
struct its_device *dev;
u32 phys_id;
u32 event_id;
} its_mapti_cmd;
struct {
struct its_device *dev;
struct its_collection *col;
u32 event_id;
} its_movi_cmd;
struct {
struct its_device *dev;
u32 event_id;
} its_discard_cmd;
struct {
struct its_collection *col;
} its_invall_cmd;
struct {
struct its_vpe *vpe;
} its_vinvall_cmd;
struct {
struct its_vpe *vpe;
struct its_collection *col;
bool valid;
} its_vmapp_cmd;
struct {
struct its_vpe *vpe;
struct its_device *dev;
u32 virt_id;
u32 event_id;
bool db_enabled;
} its_vmapti_cmd;
struct {
struct its_vpe *vpe;
struct its_device *dev;
u32 event_id;
bool db_enabled;
} its_vmovi_cmd;
struct {
struct its_vpe *vpe;
struct its_collection *col;
u16 seq_num;
u16 its_list;
} its_vmovp_cmd;
struct {
struct its_vpe *vpe;
} its_invdb_cmd;
struct {
struct its_vpe *vpe;
u8 sgi;
u8 priority;
bool enable;
bool group;
bool clear;
} its_vsgi_cmd;
};
};
/*
* The ITS command block, which is what the ITS actually parses.
*/
struct its_cmd_block {
union {
u64 raw_cmd[4];
__le64 raw_cmd_le[4];
};
};
#define ITS_CMD_QUEUE_SZ SZ_64K
#define ITS_CMD_QUEUE_NR_ENTRIES (ITS_CMD_QUEUE_SZ / sizeof(struct its_cmd_block))
typedef struct its_collection *(*its_cmd_builder_t)(struct its_node *,
struct its_cmd_block *,
struct its_cmd_desc *);
typedef struct its_vpe *(*its_cmd_vbuilder_t)(struct its_node *,
struct its_cmd_block *,
struct its_cmd_desc *);
static void its_mask_encode(u64 *raw_cmd, u64 val, int h, int l)
{
u64 mask = GENMASK_ULL(h, l);
*raw_cmd &= ~mask;
*raw_cmd |= (val << l) & mask;
}
static void its_encode_cmd(struct its_cmd_block *cmd, u8 cmd_nr)
{
its_mask_encode(&cmd->raw_cmd[0], cmd_nr, 7, 0);
}
static void its_encode_devid(struct its_cmd_block *cmd, u32 devid)
{
its_mask_encode(&cmd->raw_cmd[0], devid, 63, 32);
}
static void its_encode_event_id(struct its_cmd_block *cmd, u32 id)
{
its_mask_encode(&cmd->raw_cmd[1], id, 31, 0);
}
static void its_encode_phys_id(struct its_cmd_block *cmd, u32 phys_id)
{
its_mask_encode(&cmd->raw_cmd[1], phys_id, 63, 32);
}
static void its_encode_size(struct its_cmd_block *cmd, u8 size)
{
its_mask_encode(&cmd->raw_cmd[1], size, 4, 0);
}
static void its_encode_itt(struct its_cmd_block *cmd, u64 itt_addr)
{
its_mask_encode(&cmd->raw_cmd[2], itt_addr >> 8, 51, 8);
}
static void its_encode_valid(struct its_cmd_block *cmd, int valid)
{
its_mask_encode(&cmd->raw_cmd[2], !!valid, 63, 63);
}
static void its_encode_target(struct its_cmd_block *cmd, u64 target_addr)
{
its_mask_encode(&cmd->raw_cmd[2], target_addr >> 16, 51, 16);
}
static void its_encode_collection(struct its_cmd_block *cmd, u16 col)
{
its_mask_encode(&cmd->raw_cmd[2], col, 15, 0);
}
static void its_encode_vpeid(struct its_cmd_block *cmd, u16 vpeid)
{
its_mask_encode(&cmd->raw_cmd[1], vpeid, 47, 32);
}
static void its_encode_virt_id(struct its_cmd_block *cmd, u32 virt_id)
{
its_mask_encode(&cmd->raw_cmd[2], virt_id, 31, 0);
}
static void its_encode_db_phys_id(struct its_cmd_block *cmd, u32 db_phys_id)
{
its_mask_encode(&cmd->raw_cmd[2], db_phys_id, 63, 32);
}
static void its_encode_db_valid(struct its_cmd_block *cmd, bool db_valid)
{
its_mask_encode(&cmd->raw_cmd[2], db_valid, 0, 0);
}
static void its_encode_seq_num(struct its_cmd_block *cmd, u16 seq_num)
{
its_mask_encode(&cmd->raw_cmd[0], seq_num, 47, 32);
}
static void its_encode_its_list(struct its_cmd_block *cmd, u16 its_list)
{
its_mask_encode(&cmd->raw_cmd[1], its_list, 15, 0);
}
static void its_encode_vpt_addr(struct its_cmd_block *cmd, u64 vpt_pa)
{
its_mask_encode(&cmd->raw_cmd[3], vpt_pa >> 16, 51, 16);
}
static void its_encode_vpt_size(struct its_cmd_block *cmd, u8 vpt_size)
{
its_mask_encode(&cmd->raw_cmd[3], vpt_size, 4, 0);
}
static void its_encode_vconf_addr(struct its_cmd_block *cmd, u64 vconf_pa)
{
its_mask_encode(&cmd->raw_cmd[0], vconf_pa >> 16, 51, 16);
}
static void its_encode_alloc(struct its_cmd_block *cmd, bool alloc)
{
its_mask_encode(&cmd->raw_cmd[0], alloc, 8, 8);
}
static void its_encode_ptz(struct its_cmd_block *cmd, bool ptz)
{
its_mask_encode(&cmd->raw_cmd[0], ptz, 9, 9);
}
static void its_encode_vmapp_default_db(struct its_cmd_block *cmd,
u32 vpe_db_lpi)
{
its_mask_encode(&cmd->raw_cmd[1], vpe_db_lpi, 31, 0);
}
static void its_encode_vmovp_default_db(struct its_cmd_block *cmd,
u32 vpe_db_lpi)
{
its_mask_encode(&cmd->raw_cmd[3], vpe_db_lpi, 31, 0);
}
static void its_encode_db(struct its_cmd_block *cmd, bool db)
{
its_mask_encode(&cmd->raw_cmd[2], db, 63, 63);
}
static void its_encode_sgi_intid(struct its_cmd_block *cmd, u8 sgi)
{
its_mask_encode(&cmd->raw_cmd[0], sgi, 35, 32);
}
static void its_encode_sgi_priority(struct its_cmd_block *cmd, u8 prio)
{
its_mask_encode(&cmd->raw_cmd[0], prio >> 4, 23, 20);
}
static void its_encode_sgi_group(struct its_cmd_block *cmd, bool grp)
{
its_mask_encode(&cmd->raw_cmd[0], grp, 10, 10);
}
static void its_encode_sgi_clear(struct its_cmd_block *cmd, bool clr)
{
its_mask_encode(&cmd->raw_cmd[0], clr, 9, 9);
}
static void its_encode_sgi_enable(struct its_cmd_block *cmd, bool en)
{
its_mask_encode(&cmd->raw_cmd[0], en, 8, 8);
}
static inline void its_fixup_cmd(struct its_cmd_block *cmd)
{
/* Let's fixup BE commands */
cmd->raw_cmd_le[0] = cpu_to_le64(cmd->raw_cmd[0]);
cmd->raw_cmd_le[1] = cpu_to_le64(cmd->raw_cmd[1]);
cmd->raw_cmd_le[2] = cpu_to_le64(cmd->raw_cmd[2]);
cmd->raw_cmd_le[3] = cpu_to_le64(cmd->raw_cmd[3]);
}
static struct its_collection *its_build_mapd_cmd(struct its_node *its,
struct its_cmd_block *cmd,
struct its_cmd_desc *desc)
{
unsigned long itt_addr;
u8 size = ilog2(desc->its_mapd_cmd.dev->nr_ites);
itt_addr = virt_to_phys(desc->its_mapd_cmd.dev->itt);
itt_addr = ALIGN(itt_addr, ITS_ITT_ALIGN);
its_encode_cmd(cmd, GITS_CMD_MAPD);
its_encode_devid(cmd, desc->its_mapd_cmd.dev->device_id);
its_encode_size(cmd, size - 1);
its_encode_itt(cmd, itt_addr);
its_encode_valid(cmd, desc->its_mapd_cmd.valid);
its_fixup_cmd(cmd);
return NULL;
}
static struct its_collection *its_build_mapc_cmd(struct its_node *its,
struct its_cmd_block *cmd,
struct its_cmd_desc *desc)
{
its_encode_cmd(cmd, GITS_CMD_MAPC);
its_encode_collection(cmd, desc->its_mapc_cmd.col->col_id);
its_encode_target(cmd, desc->its_mapc_cmd.col->target_address);
its_encode_valid(cmd, desc->its_mapc_cmd.valid);
its_fixup_cmd(cmd);
return desc->its_mapc_cmd.col;
}
static struct its_collection *its_build_mapti_cmd(struct its_node *its,
struct its_cmd_block *cmd,
struct its_cmd_desc *desc)
{
struct its_collection *col;
col = dev_event_to_col(desc->its_mapti_cmd.dev,
desc->its_mapti_cmd.event_id);
its_encode_cmd(cmd, GITS_CMD_MAPTI);
its_encode_devid(cmd, desc->its_mapti_cmd.dev->device_id);
its_encode_event_id(cmd, desc->its_mapti_cmd.event_id);
its_encode_phys_id(cmd, desc->its_mapti_cmd.phys_id);
its_encode_collection(cmd, col->col_id);
its_fixup_cmd(cmd);
return valid_col(col);
}
static struct its_collection *its_build_movi_cmd(struct its_node *its,
struct its_cmd_block *cmd,
struct its_cmd_desc *desc)
{
struct its_collection *col;
col = dev_event_to_col(desc->its_movi_cmd.dev,
desc->its_movi_cmd.event_id);
its_encode_cmd(cmd, GITS_CMD_MOVI);
its_encode_devid(cmd, desc->its_movi_cmd.dev->device_id);
its_encode_event_id(cmd, desc->its_movi_cmd.event_id);
its_encode_collection(cmd, desc->its_movi_cmd.col->col_id);
its_fixup_cmd(cmd);
return valid_col(col);
}
static struct its_collection *its_build_discard_cmd(struct its_node *its,
struct its_cmd_block *cmd,
struct its_cmd_desc *desc)
{
struct its_collection *col;
col = dev_event_to_col(desc->its_discard_cmd.dev,
desc->its_discard_cmd.event_id);
its_encode_cmd(cmd, GITS_CMD_DISCARD);
its_encode_devid(cmd, desc->its_discard_cmd.dev->device_id);
its_encode_event_id(cmd, desc->its_discard_cmd.event_id);
its_fixup_cmd(cmd);
return valid_col(col);
}
static struct its_collection *its_build_inv_cmd(struct its_node *its,
struct its_cmd_block *cmd,
struct its_cmd_desc *desc)
{
struct its_collection *col;
col = dev_event_to_col(desc->its_inv_cmd.dev,
desc->its_inv_cmd.event_id);
its_encode_cmd(cmd, GITS_CMD_INV);
its_encode_devid(cmd, desc->its_inv_cmd.dev->device_id);
its_encode_event_id(cmd, desc->its_inv_cmd.event_id);
its_fixup_cmd(cmd);
return valid_col(col);
}
static struct its_collection *its_build_int_cmd(struct its_node *its,
struct its_cmd_block *cmd,
struct its_cmd_desc *desc)
{
struct its_collection *col;
col = dev_event_to_col(desc->its_int_cmd.dev,
desc->its_int_cmd.event_id);
its_encode_cmd(cmd, GITS_CMD_INT);
its_encode_devid(cmd, desc->its_int_cmd.dev->device_id);
its_encode_event_id(cmd, desc->its_int_cmd.event_id);
its_fixup_cmd(cmd);
return valid_col(col);
}
static struct its_collection *its_build_clear_cmd(struct its_node *its,
struct its_cmd_block *cmd,
struct its_cmd_desc *desc)
{
struct its_collection *col;
col = dev_event_to_col(desc->its_clear_cmd.dev,
desc->its_clear_cmd.event_id);
its_encode_cmd(cmd, GITS_CMD_CLEAR);
its_encode_devid(cmd, desc->its_clear_cmd.dev->device_id);
its_encode_event_id(cmd, desc->its_clear_cmd.event_id);
its_fixup_cmd(cmd);
return valid_col(col);
}
static struct its_collection *its_build_invall_cmd(struct its_node *its,
struct its_cmd_block *cmd,
struct its_cmd_desc *desc)
{
its_encode_cmd(cmd, GITS_CMD_INVALL);
its_encode_collection(cmd, desc->its_invall_cmd.col->col_id);
its_fixup_cmd(cmd);
return desc->its_invall_cmd.col;
}
static struct its_vpe *its_build_vinvall_cmd(struct its_node *its,
struct its_cmd_block *cmd,
struct its_cmd_desc *desc)
{
its_encode_cmd(cmd, GITS_CMD_VINVALL);
its_encode_vpeid(cmd, desc->its_vinvall_cmd.vpe->vpe_id);
its_fixup_cmd(cmd);
return valid_vpe(its, desc->its_vinvall_cmd.vpe);
}
static struct its_vpe *its_build_vmapp_cmd(struct its_node *its,
struct its_cmd_block *cmd,
struct its_cmd_desc *desc)
{
unsigned long vpt_addr, vconf_addr;
u64 target;
bool alloc;
its_encode_cmd(cmd, GITS_CMD_VMAPP);
its_encode_vpeid(cmd, desc->its_vmapp_cmd.vpe->vpe_id);
its_encode_valid(cmd, desc->its_vmapp_cmd.valid);
if (!desc->its_vmapp_cmd.valid) {
if (is_v4_1(its)) {
alloc = !atomic_dec_return(&desc->its_vmapp_cmd.vpe->vmapp_count);
its_encode_alloc(cmd, alloc);
}
goto out;
}
vpt_addr = virt_to_phys(page_address(desc->its_vmapp_cmd.vpe->vpt_page));
target = desc->its_vmapp_cmd.col->target_address + its->vlpi_redist_offset;
its_encode_target(cmd, target);
its_encode_vpt_addr(cmd, vpt_addr);
its_encode_vpt_size(cmd, LPI_NRBITS - 1);
if (!is_v4_1(its))
goto out;
vconf_addr = virt_to_phys(page_address(desc->its_vmapp_cmd.vpe->its_vm->vprop_page));
alloc = !atomic_fetch_inc(&desc->its_vmapp_cmd.vpe->vmapp_count);
its_encode_alloc(cmd, alloc);
/*
* GICv4.1 provides a way to get the VLPI state, which needs the vPE
* to be unmapped first, and in this case, we may remap the vPE
* back while the VPT is not empty. So we can't assume that the
* VPT is empty on map. This is why we never advertise PTZ.
*/
its_encode_ptz(cmd, false);
its_encode_vconf_addr(cmd, vconf_addr);
its_encode_vmapp_default_db(cmd, desc->its_vmapp_cmd.vpe->vpe_db_lpi);
out:
its_fixup_cmd(cmd);
return valid_vpe(its, desc->its_vmapp_cmd.vpe);
}
static struct its_vpe *its_build_vmapti_cmd(struct its_node *its,
struct its_cmd_block *cmd,
struct its_cmd_desc *desc)
{
u32 db;
if (!is_v4_1(its) && desc->its_vmapti_cmd.db_enabled)
db = desc->its_vmapti_cmd.vpe->vpe_db_lpi;
else
db = 1023;
its_encode_cmd(cmd, GITS_CMD_VMAPTI);
its_encode_devid(cmd, desc->its_vmapti_cmd.dev->device_id);
its_encode_vpeid(cmd, desc->its_vmapti_cmd.vpe->vpe_id);
its_encode_event_id(cmd, desc->its_vmapti_cmd.event_id);
its_encode_db_phys_id(cmd, db);
its_encode_virt_id(cmd, desc->its_vmapti_cmd.virt_id);
its_fixup_cmd(cmd);
return valid_vpe(its, desc->its_vmapti_cmd.vpe);
}
static struct its_vpe *its_build_vmovi_cmd(struct its_node *its,
struct its_cmd_block *cmd,
struct its_cmd_desc *desc)
{
u32 db;
if (!is_v4_1(its) && desc->its_vmovi_cmd.db_enabled)
db = desc->its_vmovi_cmd.vpe->vpe_db_lpi;
else
db = 1023;
its_encode_cmd(cmd, GITS_CMD_VMOVI);
its_encode_devid(cmd, desc->its_vmovi_cmd.dev->device_id);
its_encode_vpeid(cmd, desc->its_vmovi_cmd.vpe->vpe_id);
its_encode_event_id(cmd, desc->its_vmovi_cmd.event_id);
its_encode_db_phys_id(cmd, db);
its_encode_db_valid(cmd, true);
its_fixup_cmd(cmd);
return valid_vpe(its, desc->its_vmovi_cmd.vpe);
}
static struct its_vpe *its_build_vmovp_cmd(struct its_node *its,
struct its_cmd_block *cmd,
struct its_cmd_desc *desc)
{
u64 target;
target = desc->its_vmovp_cmd.col->target_address + its->vlpi_redist_offset;
its_encode_cmd(cmd, GITS_CMD_VMOVP);
its_encode_seq_num(cmd, desc->its_vmovp_cmd.seq_num);
its_encode_its_list(cmd, desc->its_vmovp_cmd.its_list);
its_encode_vpeid(cmd, desc->its_vmovp_cmd.vpe->vpe_id);
its_encode_target(cmd, target);
if (is_v4_1(its)) {
its_encode_db(cmd, true);
its_encode_vmovp_default_db(cmd, desc->its_vmovp_cmd.vpe->vpe_db_lpi);
}
its_fixup_cmd(cmd);
return valid_vpe(its, desc->its_vmovp_cmd.vpe);
}
static struct its_vpe *its_build_vinv_cmd(struct its_node *its,
struct its_cmd_block *cmd,
struct its_cmd_desc *desc)
{
struct its_vlpi_map *map;
map = dev_event_to_vlpi_map(desc->its_inv_cmd.dev,
desc->its_inv_cmd.event_id);
its_encode_cmd(cmd, GITS_CMD_INV);
its_encode_devid(cmd, desc->its_inv_cmd.dev->device_id);
its_encode_event_id(cmd, desc->its_inv_cmd.event_id);
its_fixup_cmd(cmd);
return valid_vpe(its, map->vpe);
}
static struct its_vpe *its_build_vint_cmd(struct its_node *its,
struct its_cmd_block *cmd,
struct its_cmd_desc *desc)
{
struct its_vlpi_map *map;
map = dev_event_to_vlpi_map(desc->its_int_cmd.dev,
desc->its_int_cmd.event_id);
its_encode_cmd(cmd, GITS_CMD_INT);
its_encode_devid(cmd, desc->its_int_cmd.dev->device_id);
its_encode_event_id(cmd, desc->its_int_cmd.event_id);
its_fixup_cmd(cmd);
return valid_vpe(its, map->vpe);
}
static struct its_vpe *its_build_vclear_cmd(struct its_node *its,
struct its_cmd_block *cmd,
struct its_cmd_desc *desc)
{
struct its_vlpi_map *map;
map = dev_event_to_vlpi_map(desc->its_clear_cmd.dev,
desc->its_clear_cmd.event_id);
its_encode_cmd(cmd, GITS_CMD_CLEAR);
its_encode_devid(cmd, desc->its_clear_cmd.dev->device_id);
its_encode_event_id(cmd, desc->its_clear_cmd.event_id);
its_fixup_cmd(cmd);
return valid_vpe(its, map->vpe);
}
static struct its_vpe *its_build_invdb_cmd(struct its_node *its,
struct its_cmd_block *cmd,
struct its_cmd_desc *desc)
{
if (WARN_ON(!is_v4_1(its)))
return NULL;
its_encode_cmd(cmd, GITS_CMD_INVDB);
its_encode_vpeid(cmd, desc->its_invdb_cmd.vpe->vpe_id);
its_fixup_cmd(cmd);
return valid_vpe(its, desc->its_invdb_cmd.vpe);
}
static struct its_vpe *its_build_vsgi_cmd(struct its_node *its,
struct its_cmd_block *cmd,
struct its_cmd_desc *desc)
{
if (WARN_ON(!is_v4_1(its)))
return NULL;
its_encode_cmd(cmd, GITS_CMD_VSGI);
its_encode_vpeid(cmd, desc->its_vsgi_cmd.vpe->vpe_id);
its_encode_sgi_intid(cmd, desc->its_vsgi_cmd.sgi);
its_encode_sgi_priority(cmd, desc->its_vsgi_cmd.priority);
its_encode_sgi_group(cmd, desc->its_vsgi_cmd.group);
its_encode_sgi_clear(cmd, desc->its_vsgi_cmd.clear);
its_encode_sgi_enable(cmd, desc->its_vsgi_cmd.enable);
its_fixup_cmd(cmd);
return valid_vpe(its, desc->its_vsgi_cmd.vpe);
}
static u64 its_cmd_ptr_to_offset(struct its_node *its,
struct its_cmd_block *ptr)
{
return (ptr - its->cmd_base) * sizeof(*ptr);
}
static int its_queue_full(struct its_node *its)
{
int widx;
int ridx;
widx = its->cmd_write - its->cmd_base;
ridx = readl_relaxed(its->base + GITS_CREADR) / sizeof(struct its_cmd_block);
/* This is incredibly unlikely to happen, unless the ITS locks up. */
if (((widx + 1) % ITS_CMD_QUEUE_NR_ENTRIES) == ridx)
return 1;
return 0;
}
static struct its_cmd_block *its_allocate_entry(struct its_node *its)
{
struct its_cmd_block *cmd;
u32 count = 1000000; /* 1s! */
while (its_queue_full(its)) {
count--;
if (!count) {
pr_err_ratelimited("ITS queue not draining\n");
return NULL;
}
cpu_relax();
udelay(1);
}
cmd = its->cmd_write++;
/* Handle queue wrapping */
if (its->cmd_write == (its->cmd_base + ITS_CMD_QUEUE_NR_ENTRIES))
its->cmd_write = its->cmd_base;
/* Clear command */
cmd->raw_cmd[0] = 0;
cmd->raw_cmd[1] = 0;
cmd->raw_cmd[2] = 0;
cmd->raw_cmd[3] = 0;
return cmd;
}
static struct its_cmd_block *its_post_commands(struct its_node *its)
{
u64 wr = its_cmd_ptr_to_offset(its, its->cmd_write);
writel_relaxed(wr, its->base + GITS_CWRITER);
return its->cmd_write;
}
static void its_flush_cmd(struct its_node *its, struct its_cmd_block *cmd)
{
/*
* Make sure the commands written to memory are observable by
* the ITS.
*/
if (its->flags & ITS_FLAGS_CMDQ_NEEDS_FLUSHING)
gic_flush_dcache_to_poc(cmd, sizeof(*cmd));
else
dsb(ishst);
}
static int its_wait_for_range_completion(struct its_node *its,
u64 prev_idx,
struct its_cmd_block *to)
{
u64 rd_idx, to_idx, linear_idx;
u32 count = 1000000; /* 1s! */
/* Linearize to_idx if the command set has wrapped around */
to_idx = its_cmd_ptr_to_offset(its, to);
if (to_idx < prev_idx)
to_idx += ITS_CMD_QUEUE_SZ;
linear_idx = prev_idx;
while (1) {
s64 delta;
rd_idx = readl_relaxed(its->base + GITS_CREADR);
/*
* Compute the read pointer progress, taking the
* potential wrap-around into account.
*/
delta = rd_idx - prev_idx;
if (rd_idx < prev_idx)
delta += ITS_CMD_QUEUE_SZ;
linear_idx += delta;
if (linear_idx >= to_idx)
break;
count--;
if (!count) {
pr_err_ratelimited("ITS queue timeout (%llu %llu)\n",
to_idx, linear_idx);
return -1;
}
prev_idx = rd_idx;
cpu_relax();
udelay(1);
}
return 0;
}
/* Warning, macro hell follows */
#define BUILD_SINGLE_CMD_FUNC(name, buildtype, synctype, buildfn) \
void name(struct its_node *its, \
buildtype builder, \
struct its_cmd_desc *desc) \
{ \
struct its_cmd_block *cmd, *sync_cmd, *next_cmd; \
synctype *sync_obj; \
unsigned long flags; \
u64 rd_idx; \
\
raw_spin_lock_irqsave(&its->lock, flags); \
\
cmd = its_allocate_entry(its); \
if (!cmd) { /* We're soooooo screewed... */ \
raw_spin_unlock_irqrestore(&its->lock, flags); \
return; \
} \
sync_obj = builder(its, cmd, desc); \
its_flush_cmd(its, cmd); \
\
if (sync_obj) { \
sync_cmd = its_allocate_entry(its); \
if (!sync_cmd) \
goto post; \
\
buildfn(its, sync_cmd, sync_obj); \
its_flush_cmd(its, sync_cmd); \
} \
\
post: \
rd_idx = readl_relaxed(its->base + GITS_CREADR); \
next_cmd = its_post_commands(its); \
raw_spin_unlock_irqrestore(&its->lock, flags); \
\
if (its_wait_for_range_completion(its, rd_idx, next_cmd)) \
pr_err_ratelimited("ITS cmd %ps failed\n", builder); \
}
static void its_build_sync_cmd(struct its_node *its,
struct its_cmd_block *sync_cmd,
struct its_collection *sync_col)
{
its_encode_cmd(sync_cmd, GITS_CMD_SYNC);
its_encode_target(sync_cmd, sync_col->target_address);
its_fixup_cmd(sync_cmd);
}
static BUILD_SINGLE_CMD_FUNC(its_send_single_command, its_cmd_builder_t,
struct its_collection, its_build_sync_cmd)
static void its_build_vsync_cmd(struct its_node *its,
struct its_cmd_block *sync_cmd,
struct its_vpe *sync_vpe)
{
its_encode_cmd(sync_cmd, GITS_CMD_VSYNC);
its_encode_vpeid(sync_cmd, sync_vpe->vpe_id);
its_fixup_cmd(sync_cmd);
}
static BUILD_SINGLE_CMD_FUNC(its_send_single_vcommand, its_cmd_vbuilder_t,
struct its_vpe, its_build_vsync_cmd)
static void its_send_int(struct its_device *dev, u32 event_id)
{
struct its_cmd_desc desc;
desc.its_int_cmd.dev = dev;
desc.its_int_cmd.event_id = event_id;
its_send_single_command(dev->its, its_build_int_cmd, &desc);
}
static void its_send_clear(struct its_device *dev, u32 event_id)
{
struct its_cmd_desc desc;
desc.its_clear_cmd.dev = dev;
desc.its_clear_cmd.event_id = event_id;
its_send_single_command(dev->its, its_build_clear_cmd, &desc);
}
static void its_send_inv(struct its_device *dev, u32 event_id)
{
struct its_cmd_desc desc;
desc.its_inv_cmd.dev = dev;
desc.its_inv_cmd.event_id = event_id;
its_send_single_command(dev->its, its_build_inv_cmd, &desc);
}
static void its_send_mapd(struct its_device *dev, int valid)
{
struct its_cmd_desc desc;
desc.its_mapd_cmd.dev = dev;
desc.its_mapd_cmd.valid = !!valid;
its_send_single_command(dev->its, its_build_mapd_cmd, &desc);
}
static void its_send_mapc(struct its_node *its, struct its_collection *col,
int valid)
{
struct its_cmd_desc desc;
desc.its_mapc_cmd.col = col;
desc.its_mapc_cmd.valid = !!valid;
its_send_single_command(its, its_build_mapc_cmd, &desc);
}
static void its_send_mapti(struct its_device *dev, u32 irq_id, u32 id)
{
struct its_cmd_desc desc;
desc.its_mapti_cmd.dev = dev;
desc.its_mapti_cmd.phys_id = irq_id;
desc.its_mapti_cmd.event_id = id;
its_send_single_command(dev->its, its_build_mapti_cmd, &desc);
}
static void its_send_movi(struct its_device *dev,
struct its_collection *col, u32 id)
{
struct its_cmd_desc desc;
desc.its_movi_cmd.dev = dev;
desc.its_movi_cmd.col = col;
desc.its_movi_cmd.event_id = id;
its_send_single_command(dev->its, its_build_movi_cmd, &desc);
}
static void its_send_discard(struct its_device *dev, u32 id)
{
struct its_cmd_desc desc;
desc.its_discard_cmd.dev = dev;
desc.its_discard_cmd.event_id = id;
its_send_single_command(dev->its, its_build_discard_cmd, &desc);
}
static void its_send_invall(struct its_node *its, struct its_collection *col)
{
struct its_cmd_desc desc;
desc.its_invall_cmd.col = col;
its_send_single_command(its, its_build_invall_cmd, &desc);
}
static void its_send_vmapti(struct its_device *dev, u32 id)
{
struct its_vlpi_map *map = dev_event_to_vlpi_map(dev, id);
struct its_cmd_desc desc;
desc.its_vmapti_cmd.vpe = map->vpe;
desc.its_vmapti_cmd.dev = dev;
desc.its_vmapti_cmd.virt_id = map->vintid;
desc.its_vmapti_cmd.event_id = id;
desc.its_vmapti_cmd.db_enabled = map->db_enabled;
its_send_single_vcommand(dev->its, its_build_vmapti_cmd, &desc);
}
static void its_send_vmovi(struct its_device *dev, u32 id)
{
struct its_vlpi_map *map = dev_event_to_vlpi_map(dev, id);
struct its_cmd_desc desc;
desc.its_vmovi_cmd.vpe = map->vpe;
desc.its_vmovi_cmd.dev = dev;
desc.its_vmovi_cmd.event_id = id;
desc.its_vmovi_cmd.db_enabled = map->db_enabled;
its_send_single_vcommand(dev->its, its_build_vmovi_cmd, &desc);
}
static void its_send_vmapp(struct its_node *its,
struct its_vpe *vpe, bool valid)
{
struct its_cmd_desc desc;
desc.its_vmapp_cmd.vpe = vpe;
desc.its_vmapp_cmd.valid = valid;
desc.its_vmapp_cmd.col = &its->collections[vpe->col_idx];
its_send_single_vcommand(its, its_build_vmapp_cmd, &desc);
}
static void its_send_vmovp(struct its_vpe *vpe)
{
struct its_cmd_desc desc = {};
struct its_node *its;
unsigned long flags;
int col_id = vpe->col_idx;
desc.its_vmovp_cmd.vpe = vpe;
if (!its_list_map) {
its = list_first_entry(&its_nodes, struct its_node, entry);
desc.its_vmovp_cmd.col = &its->collections[col_id];
its_send_single_vcommand(its, its_build_vmovp_cmd, &desc);
return;
}
/*
* Yet another marvel of the architecture. If using the
* its_list "feature", we need to make sure that all ITSs
* receive all VMOVP commands in the same order. The only way
* to guarantee this is to make vmovp a serialization point.
*
* Wall <-- Head.
*/
raw_spin_lock_irqsave(&vmovp_lock, flags);
desc.its_vmovp_cmd.seq_num = vmovp_seq_num++;
desc.its_vmovp_cmd.its_list = get_its_list(vpe->its_vm);
/* Emit VMOVPs */
list_for_each_entry(its, &its_nodes, entry) {
if (!is_v4(its))
continue;
if (!require_its_list_vmovp(vpe->its_vm, its))
continue;
desc.its_vmovp_cmd.col = &its->collections[col_id];
its_send_single_vcommand(its, its_build_vmovp_cmd, &desc);
}
raw_spin_unlock_irqrestore(&vmovp_lock, flags);
}
static void its_send_vinvall(struct its_node *its, struct its_vpe *vpe)
{
struct its_cmd_desc desc;
desc.its_vinvall_cmd.vpe = vpe;
its_send_single_vcommand(its, its_build_vinvall_cmd, &desc);
}
static void its_send_vinv(struct its_device *dev, u32 event_id)
{
struct its_cmd_desc desc;
/*
* There is no real VINV command. This is just a normal INV,
* with a VSYNC instead of a SYNC.
*/
desc.its_inv_cmd.dev = dev;
desc.its_inv_cmd.event_id = event_id;
its_send_single_vcommand(dev->its, its_build_vinv_cmd, &desc);
}
static void its_send_vint(struct its_device *dev, u32 event_id)
{
struct its_cmd_desc desc;
/*
* There is no real VINT command. This is just a normal INT,
* with a VSYNC instead of a SYNC.
*/
desc.its_int_cmd.dev = dev;
desc.its_int_cmd.event_id = event_id;
its_send_single_vcommand(dev->its, its_build_vint_cmd, &desc);
}
static void its_send_vclear(struct its_device *dev, u32 event_id)
{
struct its_cmd_desc desc;
/*
* There is no real VCLEAR command. This is just a normal CLEAR,
* with a VSYNC instead of a SYNC.
*/
desc.its_clear_cmd.dev = dev;
desc.its_clear_cmd.event_id = event_id;
its_send_single_vcommand(dev->its, its_build_vclear_cmd, &desc);
}
static void its_send_invdb(struct its_node *its, struct its_vpe *vpe)
{
struct its_cmd_desc desc;
desc.its_invdb_cmd.vpe = vpe;
its_send_single_vcommand(its, its_build_invdb_cmd, &desc);
}
/*
* irqchip functions - assumes MSI, mostly.
*/
static void lpi_write_config(struct irq_data *d, u8 clr, u8 set)
{
struct its_vlpi_map *map = get_vlpi_map(d);
irq_hw_number_t hwirq;
void *va;
u8 *cfg;
if (map) {
va = page_address(map->vm->vprop_page);
hwirq = map->vintid;
/* Remember the updated property */
map->properties &= ~clr;
map->properties |= set | LPI_PROP_GROUP1;
} else {
va = gic_rdists->prop_table_va;
hwirq = d->hwirq;
}
cfg = va + hwirq - 8192;
*cfg &= ~clr;
*cfg |= set | LPI_PROP_GROUP1;
/*
* Make the above write visible to the redistributors.
* And yes, we're flushing exactly: One. Single. Byte.
* Humpf...
*/
if (gic_rdists->flags & RDIST_FLAGS_PROPBASE_NEEDS_FLUSHING)
gic_flush_dcache_to_poc(cfg, sizeof(*cfg));
else
dsb(ishst);
}
static void wait_for_syncr(void __iomem *rdbase)
{
while (readl_relaxed(rdbase + GICR_SYNCR) & 1)
cpu_relax();
}
static void direct_lpi_inv(struct irq_data *d)
{
struct its_vlpi_map *map = get_vlpi_map(d);
void __iomem *rdbase;
unsigned long flags;
u64 val;
int cpu;
if (map) {
struct its_device *its_dev = irq_data_get_irq_chip_data(d);
WARN_ON(!is_v4_1(its_dev->its));
val = GICR_INVLPIR_V;
val |= FIELD_PREP(GICR_INVLPIR_VPEID, map->vpe->vpe_id);
val |= FIELD_PREP(GICR_INVLPIR_INTID, map->vintid);
} else {
val = d->hwirq;
}
/* Target the redistributor this LPI is currently routed to */
cpu = irq_to_cpuid_lock(d, &flags);
raw_spin_lock(&gic_data_rdist_cpu(cpu)->rd_lock);
rdbase = per_cpu_ptr(gic_rdists->rdist, cpu)->rd_base;
gic_write_lpir(val, rdbase + GICR_INVLPIR);
wait_for_syncr(rdbase);
raw_spin_unlock(&gic_data_rdist_cpu(cpu)->rd_lock);
irq_to_cpuid_unlock(d, flags);
}
static void lpi_update_config(struct irq_data *d, u8 clr, u8 set)
{
struct its_device *its_dev = irq_data_get_irq_chip_data(d);
lpi_write_config(d, clr, set);
if (gic_rdists->has_direct_lpi &&
(is_v4_1(its_dev->its) || !irqd_is_forwarded_to_vcpu(d)))
direct_lpi_inv(d);
else if (!irqd_is_forwarded_to_vcpu(d))
its_send_inv(its_dev, its_get_event_id(d));
else
its_send_vinv(its_dev, its_get_event_id(d));
}
static void its_vlpi_set_doorbell(struct irq_data *d, bool enable)
{
struct its_device *its_dev = irq_data_get_irq_chip_data(d);
u32 event = its_get_event_id(d);
struct its_vlpi_map *map;
/*
* GICv4.1 does away with the per-LPI nonsense, nothing to do
* here.
*/
if (is_v4_1(its_dev->its))
return;
map = dev_event_to_vlpi_map(its_dev, event);
if (map->db_enabled == enable)
return;
map->db_enabled = enable;
/*
* More fun with the architecture:
*
* Ideally, we'd issue a VMAPTI to set the doorbell to its LPI
* value or to 1023, depending on the enable bit. But that
* would be issuing a mapping for an /existing/ DevID+EventID
* pair, which is UNPREDICTABLE. Instead, let's issue a VMOVI
* to the /same/ vPE, using this opportunity to adjust the
* doorbell. Mouahahahaha. We loves it, Precious.
*/
its_send_vmovi(its_dev, event);
}
static void its_mask_irq(struct irq_data *d)
{
if (irqd_is_forwarded_to_vcpu(d))
its_vlpi_set_doorbell(d, false);
lpi_update_config(d, LPI_PROP_ENABLED, 0);
}
static void its_unmask_irq(struct irq_data *d)
{
if (irqd_is_forwarded_to_vcpu(d))
its_vlpi_set_doorbell(d, true);
lpi_update_config(d, 0, LPI_PROP_ENABLED);
}
static __maybe_unused u32 its_read_lpi_count(struct irq_data *d, int cpu)
{
if (irqd_affinity_is_managed(d))
return atomic_read(&per_cpu_ptr(&cpu_lpi_count, cpu)->managed);
return atomic_read(&per_cpu_ptr(&cpu_lpi_count, cpu)->unmanaged);
}
static void its_inc_lpi_count(struct irq_data *d, int cpu)
{
if (irqd_affinity_is_managed(d))
atomic_inc(&per_cpu_ptr(&cpu_lpi_count, cpu)->managed);
else
atomic_inc(&per_cpu_ptr(&cpu_lpi_count, cpu)->unmanaged);
}
static void its_dec_lpi_count(struct irq_data *d, int cpu)
{
if (irqd_affinity_is_managed(d))
atomic_dec(&per_cpu_ptr(&cpu_lpi_count, cpu)->managed);
else
atomic_dec(&per_cpu_ptr(&cpu_lpi_count, cpu)->unmanaged);
}
static unsigned int cpumask_pick_least_loaded(struct irq_data *d,
const struct cpumask *cpu_mask)
{
unsigned int cpu = nr_cpu_ids, tmp;
int count = S32_MAX;
for_each_cpu(tmp, cpu_mask) {
int this_count = its_read_lpi_count(d, tmp);
if (this_count < count) {
cpu = tmp;
count = this_count;
}
}
return cpu;
}
/*
* As suggested by Thomas Gleixner in:
* https://lore.kernel.org/r/87h80q2aoc.fsf@nanos.tec.linutronix.de
*/
static int its_select_cpu(struct irq_data *d,
const struct cpumask *aff_mask)
{
struct its_device *its_dev = irq_data_get_irq_chip_data(d);
cpumask_var_t tmpmask;
int cpu, node;
if (!alloc_cpumask_var(&tmpmask, GFP_ATOMIC))
return -ENOMEM;
node = its_dev->its->numa_node;
if (!irqd_affinity_is_managed(d)) {
/* First try the NUMA node */
if (node != NUMA_NO_NODE) {
/*
* Try the intersection of the affinity mask and the
* node mask (and the online mask, just to be safe).
*/
cpumask_and(tmpmask, cpumask_of_node(node), aff_mask);
cpumask_and(tmpmask, tmpmask, cpu_online_mask);
/*
* Ideally, we would check if the mask is empty, and
* try again on the full node here.
*
* But it turns out that the way ACPI describes the
* affinity for ITSs only deals about memory, and
* not target CPUs, so it cannot describe a single
* ITS placed next to two NUMA nodes.
*
* Instead, just fallback on the online mask. This
* diverges from Thomas' suggestion above.
*/
cpu = cpumask_pick_least_loaded(d, tmpmask);
if (cpu < nr_cpu_ids)
goto out;
/* If we can't cross sockets, give up */
if ((its_dev->its->flags & ITS_FLAGS_WORKAROUND_CAVIUM_23144))
goto out;
/* If the above failed, expand the search */
}
/* Try the intersection of the affinity and online masks */
cpumask_and(tmpmask, aff_mask, cpu_online_mask);
/* If that doesn't fly, the online mask is the last resort */
if (cpumask_empty(tmpmask))
cpumask_copy(tmpmask, cpu_online_mask);
cpu = cpumask_pick_least_loaded(d, tmpmask);
} else {
cpumask_copy(tmpmask, aff_mask);
/* If we cannot cross sockets, limit the search to that node */
if ((its_dev->its->flags & ITS_FLAGS_WORKAROUND_CAVIUM_23144) &&
node != NUMA_NO_NODE)
cpumask_and(tmpmask, tmpmask, cpumask_of_node(node));
cpu = cpumask_pick_least_loaded(d, tmpmask);
}
out:
free_cpumask_var(tmpmask);
pr_debug("IRQ%d -> %*pbl CPU%d\n", d->irq, cpumask_pr_args(aff_mask), cpu);
return cpu;
}
static int its_set_affinity(struct irq_data *d, const struct cpumask *mask_val,
bool force)
{
struct its_device *its_dev = irq_data_get_irq_chip_data(d);
struct its_collection *target_col;
u32 id = its_get_event_id(d);
int cpu, prev_cpu;
/* A forwarded interrupt should use irq_set_vcpu_affinity */
if (irqd_is_forwarded_to_vcpu(d))
return -EINVAL;
prev_cpu = its_dev->event_map.col_map[id];
its_dec_lpi_count(d, prev_cpu);
if (!force)
cpu = its_select_cpu(d, mask_val);
else
cpu = cpumask_pick_least_loaded(d, mask_val);
if (cpu < 0 || cpu >= nr_cpu_ids)
goto err;
/* don't set the affinity when the target cpu is same as current one */
if (cpu != prev_cpu) {
target_col = &its_dev->its->collections[cpu];
its_send_movi(its_dev, target_col, id);
its_dev->event_map.col_map[id] = cpu;
irq_data_update_effective_affinity(d, cpumask_of(cpu));
}
its_inc_lpi_count(d, cpu);
return IRQ_SET_MASK_OK_DONE;
err:
its_inc_lpi_count(d, prev_cpu);
return -EINVAL;
}
static u64 its_irq_get_msi_base(struct its_device *its_dev)
{
struct its_node *its = its_dev->its;
return its->phys_base + GITS_TRANSLATER;
}
static void its_irq_compose_msi_msg(struct irq_data *d, struct msi_msg *msg)
{
struct its_device *its_dev = irq_data_get_irq_chip_data(d);
struct its_node *its;
u64 addr;
its = its_dev->its;
addr = its->get_msi_base(its_dev);
msg->address_lo = lower_32_bits(addr);
msg->address_hi = upper_32_bits(addr);
msg->data = its_get_event_id(d);
iommu_dma_compose_msi_msg(irq_data_get_msi_desc(d), msg);
}
static int its_irq_set_irqchip_state(struct irq_data *d,
enum irqchip_irq_state which,
bool state)
{
struct its_device *its_dev = irq_data_get_irq_chip_data(d);
u32 event = its_get_event_id(d);
if (which != IRQCHIP_STATE_PENDING)
return -EINVAL;
if (irqd_is_forwarded_to_vcpu(d)) {
if (state)
its_send_vint(its_dev, event);
else
its_send_vclear(its_dev, event);
} else {
if (state)
its_send_int(its_dev, event);
else
its_send_clear(its_dev, event);
}
return 0;
}
static int its_irq_retrigger(struct irq_data *d)
{
return !its_irq_set_irqchip_state(d, IRQCHIP_STATE_PENDING, true);
}
/*
* Two favourable cases:
*
* (a) Either we have a GICv4.1, and all vPEs have to be mapped at all times
* for vSGI delivery
*
* (b) Or the ITSs do not use a list map, meaning that VMOVP is cheap enough
* and we're better off mapping all VPEs always
*
* If neither (a) nor (b) is true, then we map vPEs on demand.
*
*/
static bool gic_requires_eager_mapping(void)
{
if (!its_list_map || gic_rdists->has_rvpeid)
return true;
return false;
}
static void its_map_vm(struct its_node *its, struct its_vm *vm)
{
unsigned long flags;
if (gic_requires_eager_mapping())
return;
raw_spin_lock_irqsave(&vmovp_lock, flags);
/*
* If the VM wasn't mapped yet, iterate over the vpes and get
* them mapped now.
*/
vm->vlpi_count[its->list_nr]++;
if (vm->vlpi_count[its->list_nr] == 1) {
int i;
for (i = 0; i < vm->nr_vpes; i++) {
struct its_vpe *vpe = vm->vpes[i];
struct irq_data *d = irq_get_irq_data(vpe->irq);
/* Map the VPE to the first possible CPU */
vpe->col_idx = cpumask_first(cpu_online_mask);
its_send_vmapp(its, vpe, true);
its_send_vinvall(its, vpe);
irq_data_update_effective_affinity(d, cpumask_of(vpe->col_idx));
}
}
raw_spin_unlock_irqrestore(&vmovp_lock, flags);
}
static void its_unmap_vm(struct its_node *its, struct its_vm *vm)
{
unsigned long flags;
/* Not using the ITS list? Everything is always mapped. */
if (gic_requires_eager_mapping())
return;
raw_spin_lock_irqsave(&vmovp_lock, flags);
if (!--vm->vlpi_count[its->list_nr]) {
int i;
for (i = 0; i < vm->nr_vpes; i++)
its_send_vmapp(its, vm->vpes[i], false);
}
raw_spin_unlock_irqrestore(&vmovp_lock, flags);
}
static int its_vlpi_map(struct irq_data *d, struct its_cmd_info *info)
{
struct its_device *its_dev = irq_data_get_irq_chip_data(d);
u32 event = its_get_event_id(d);
int ret = 0;
if (!info->map)
return -EINVAL;
raw_spin_lock(&its_dev->event_map.vlpi_lock);
if (!its_dev->event_map.vm) {
struct its_vlpi_map *maps;
maps = kcalloc(its_dev->event_map.nr_lpis, sizeof(*maps),
GFP_ATOMIC);
if (!maps) {
ret = -ENOMEM;
goto out;
}
its_dev->event_map.vm = info->map->vm;
its_dev->event_map.vlpi_maps = maps;
} else if (its_dev->event_map.vm != info->map->vm) {
ret = -EINVAL;
goto out;
}
/* Get our private copy of the mapping information */
its_dev->event_map.vlpi_maps[event] = *info->map;
if (irqd_is_forwarded_to_vcpu(d)) {
/* Already mapped, move it around */
its_send_vmovi(its_dev, event);
} else {
/* Ensure all the VPEs are mapped on this ITS */
its_map_vm(its_dev->its, info->map->vm);
/*
* Flag the interrupt as forwarded so that we can
* start poking the virtual property table.
*/
irqd_set_forwarded_to_vcpu(d);
/* Write out the property to the prop table */
lpi_write_config(d, 0xff, info->map->properties);
/* Drop the physical mapping */
its_send_discard(its_dev, event);
/* and install the virtual one */
its_send_vmapti(its_dev, event);
/* Increment the number of VLPIs */
its_dev->event_map.nr_vlpis++;
}
out:
raw_spin_unlock(&its_dev->event_map.vlpi_lock);
return ret;
}
static int its_vlpi_get(struct irq_data *d, struct its_cmd_info *info)
{
struct its_device *its_dev = irq_data_get_irq_chip_data(d);
struct its_vlpi_map *map;
int ret = 0;
raw_spin_lock(&its_dev->event_map.vlpi_lock);
map = get_vlpi_map(d);
if (!its_dev->event_map.vm || !map) {
ret = -EINVAL;
goto out;
}
/* Copy our mapping information to the incoming request */
*info->map = *map;
out:
raw_spin_unlock(&its_dev->event_map.vlpi_lock);
return ret;
}
static int its_vlpi_unmap(struct irq_data *d)
{
struct its_device *its_dev = irq_data_get_irq_chip_data(d);
u32 event = its_get_event_id(d);
int ret = 0;
raw_spin_lock(&its_dev->event_map.vlpi_lock);
if (!its_dev->event_map.vm || !irqd_is_forwarded_to_vcpu(d)) {
ret = -EINVAL;
goto out;
}
/* Drop the virtual mapping */
its_send_discard(its_dev, event);
/* and restore the physical one */
irqd_clr_forwarded_to_vcpu(d);
its_send_mapti(its_dev, d->hwirq, event);
lpi_update_config(d, 0xff, (LPI_PROP_DEFAULT_PRIO |
LPI_PROP_ENABLED |
LPI_PROP_GROUP1));
/* Potentially unmap the VM from this ITS */
its_unmap_vm(its_dev->its, its_dev->event_map.vm);
/*
* Drop the refcount and make the device available again if
* this was the last VLPI.
*/
if (!--its_dev->event_map.nr_vlpis) {
its_dev->event_map.vm = NULL;
kfree(its_dev->event_map.vlpi_maps);
}
out:
raw_spin_unlock(&its_dev->event_map.vlpi_lock);
return ret;
}
static int its_vlpi_prop_update(struct irq_data *d, struct its_cmd_info *info)
{
struct its_device *its_dev = irq_data_get_irq_chip_data(d);
if (!its_dev->event_map.vm || !irqd_is_forwarded_to_vcpu(d))
return -EINVAL;
if (info->cmd_type == PROP_UPDATE_AND_INV_VLPI)
lpi_update_config(d, 0xff, info->config);
else
lpi_write_config(d, 0xff, info->config);
its_vlpi_set_doorbell(d, !!(info->config & LPI_PROP_ENABLED));
return 0;
}
static int its_irq_set_vcpu_affinity(struct irq_data *d, void *vcpu_info)
{
struct its_device *its_dev = irq_data_get_irq_chip_data(d);
struct its_cmd_info *info = vcpu_info;
/* Need a v4 ITS */
if (!is_v4(its_dev->its))
return -EINVAL;
/* Unmap request? */
if (!info)
return its_vlpi_unmap(d);
switch (info->cmd_type) {
case MAP_VLPI:
return its_vlpi_map(d, info);
case GET_VLPI:
return its_vlpi_get(d, info);
case PROP_UPDATE_VLPI:
case PROP_UPDATE_AND_INV_VLPI:
return its_vlpi_prop_update(d, info);
default:
return -EINVAL;
}
}
static struct irq_chip its_irq_chip = {
.name = "ITS",
.irq_mask = its_mask_irq,
.irq_unmask = its_unmask_irq,
.irq_eoi = irq_chip_eoi_parent,
.irq_set_affinity = its_set_affinity,
.irq_compose_msi_msg = its_irq_compose_msi_msg,
.irq_set_irqchip_state = its_irq_set_irqchip_state,
.irq_retrigger = its_irq_retrigger,
.irq_set_vcpu_affinity = its_irq_set_vcpu_affinity,
};
/*
* How we allocate LPIs:
*
* lpi_range_list contains ranges of LPIs that are to available to
* allocate from. To allocate LPIs, just pick the first range that
* fits the required allocation, and reduce it by the required
* amount. Once empty, remove the range from the list.
*
* To free a range of LPIs, add a free range to the list, sort it and
* merge the result if the new range happens to be adjacent to an
* already free block.
*
* The consequence of the above is that allocation is cost is low, but
* freeing is expensive. We assumes that freeing rarely occurs.
*/
#define ITS_MAX_LPI_NRBITS 16 /* 64K LPIs */
static DEFINE_MUTEX(lpi_range_lock);
static LIST_HEAD(lpi_range_list);
struct lpi_range {
struct list_head entry;
u32 base_id;
u32 span;
};
static struct lpi_range *mk_lpi_range(u32 base, u32 span)
{
struct lpi_range *range;
range = kmalloc(sizeof(*range), GFP_KERNEL);
if (range) {
range->base_id = base;
range->span = span;
}
return range;
}
static int alloc_lpi_range(u32 nr_lpis, u32 *base)
{
struct lpi_range *range, *tmp;
int err = -ENOSPC;
mutex_lock(&lpi_range_lock);
list_for_each_entry_safe(range, tmp, &lpi_range_list, entry) {
if (range->span >= nr_lpis) {
*base = range->base_id;
range->base_id += nr_lpis;
range->span -= nr_lpis;
if (range->span == 0) {
list_del(&range->entry);
kfree(range);
}
err = 0;
break;
}
}
mutex_unlock(&lpi_range_lock);
pr_debug("ITS: alloc %u:%u\n", *base, nr_lpis);
return err;
}
static void merge_lpi_ranges(struct lpi_range *a, struct lpi_range *b)
{
if (&a->entry == &lpi_range_list || &b->entry == &lpi_range_list)
return;
if (a->base_id + a->span != b->base_id)
return;
b->base_id = a->base_id;
b->span += a->span;
list_del(&a->entry);
kfree(a);
}
static int free_lpi_range(u32 base, u32 nr_lpis)
{
struct lpi_range *new, *old;
new = mk_lpi_range(base, nr_lpis);
if (!new)
return -ENOMEM;
mutex_lock(&lpi_range_lock);
list_for_each_entry_reverse(old, &lpi_range_list, entry) {
if (old->base_id < base)
break;
}
/*
* old is the last element with ->base_id smaller than base,
* so new goes right after it. If there are no elements with
* ->base_id smaller than base, &old->entry ends up pointing
* at the head of the list, and inserting new it the start of
* the list is the right thing to do in that case as well.
*/
list_add(&new->entry, &old->entry);
/*
* Now check if we can merge with the preceding and/or
* following ranges.
*/
merge_lpi_ranges(old, new);
merge_lpi_ranges(new, list_next_entry(new, entry));
mutex_unlock(&lpi_range_lock);
return 0;
}
static int __init its_lpi_init(u32 id_bits)
{
u32 lpis = (1UL << id_bits) - 8192;
u32 numlpis;
int err;
numlpis = 1UL << GICD_TYPER_NUM_LPIS(gic_rdists->gicd_typer);
if (numlpis > 2 && !WARN_ON(numlpis > lpis)) {
lpis = numlpis;
pr_info("ITS: Using hypervisor restricted LPI range [%u]\n",
lpis);
}
/*
* Initializing the allocator is just the same as freeing the
* full range of LPIs.
*/
err = free_lpi_range(8192, lpis);
pr_debug("ITS: Allocator initialized for %u LPIs\n", lpis);
return err;
}
static unsigned long *its_lpi_alloc(int nr_irqs, u32 *base, int *nr_ids)
{
unsigned long *bitmap = NULL;
int err = 0;
do {
err = alloc_lpi_range(nr_irqs, base);
if (!err)
break;
nr_irqs /= 2;
} while (nr_irqs > 0);
if (!nr_irqs)
err = -ENOSPC;
if (err)
goto out;
bitmap = bitmap_zalloc(nr_irqs, GFP_ATOMIC);
if (!bitmap)
goto out;
*nr_ids = nr_irqs;
out:
if (!bitmap)
*base = *nr_ids = 0;
return bitmap;
}
static void its_lpi_free(unsigned long *bitmap, u32 base, u32 nr_ids)
{
WARN_ON(free_lpi_range(base, nr_ids));
bitmap_free(bitmap);
}
static void gic_reset_prop_table(void *va)
{
/* Priority 0xa0, Group-1, disabled */
memset(va, LPI_PROP_DEFAULT_PRIO | LPI_PROP_GROUP1, LPI_PROPBASE_SZ);
/* Make sure the GIC will observe the written configuration */
gic_flush_dcache_to_poc(va, LPI_PROPBASE_SZ);
}
static struct page *its_allocate_prop_table(gfp_t gfp_flags)
{
struct page *prop_page;
prop_page = alloc_pages(gfp_flags, get_order(LPI_PROPBASE_SZ));
if (!prop_page)
return NULL;
gic_reset_prop_table(page_address(prop_page));
return prop_page;
}
static void its_free_prop_table(struct page *prop_page)
{
free_pages((unsigned long)page_address(prop_page),
get_order(LPI_PROPBASE_SZ));
}
static bool gic_check_reserved_range(phys_addr_t addr, unsigned long size)
{
phys_addr_t start, end, addr_end;
u64 i;
/*
* We don't bother checking for a kdump kernel as by
* construction, the LPI tables are out of this kernel's
* memory map.
*/
if (is_kdump_kernel())
return true;
addr_end = addr + size - 1;
for_each_reserved_mem_range(i, &start, &end) {
if (addr >= start && addr_end <= end)
return true;
}
/* Not found, not a good sign... */
pr_warn("GICv3: Expected reserved range [%pa:%pa], not found\n",
&addr, &addr_end);
add_taint(TAINT_CRAP, LOCKDEP_STILL_OK);
return false;
}
static int gic_reserve_range(phys_addr_t addr, unsigned long size)
{
if (efi_enabled(EFI_CONFIG_TABLES))
return efi_mem_reserve_persistent(addr, size);
return 0;
}
static int __init its_setup_lpi_prop_table(void)
{
if (gic_rdists->flags & RDIST_FLAGS_RD_TABLES_PREALLOCATED) {
u64 val;
val = gicr_read_propbaser(gic_data_rdist_rd_base() + GICR_PROPBASER);
lpi_id_bits = (val & GICR_PROPBASER_IDBITS_MASK) + 1;
gic_rdists->prop_table_pa = val & GENMASK_ULL(51, 12);
gic_rdists->prop_table_va = memremap(gic_rdists->prop_table_pa,
LPI_PROPBASE_SZ,
MEMREMAP_WB);
gic_reset_prop_table(gic_rdists->prop_table_va);
} else {
struct page *page;
lpi_id_bits = min_t(u32,
GICD_TYPER_ID_BITS(gic_rdists->gicd_typer),
ITS_MAX_LPI_NRBITS);
page = its_allocate_prop_table(GFP_NOWAIT);
if (!page) {
pr_err("Failed to allocate PROPBASE\n");
return -ENOMEM;
}
gic_rdists->prop_table_pa = page_to_phys(page);
gic_rdists->prop_table_va = page_address(page);
WARN_ON(gic_reserve_range(gic_rdists->prop_table_pa,
LPI_PROPBASE_SZ));
}
pr_info("GICv3: using LPI property table @%pa\n",
&gic_rdists->prop_table_pa);
return its_lpi_init(lpi_id_bits);
}
static const char *its_base_type_string[] = {
[GITS_BASER_TYPE_DEVICE] = "Devices",
[GITS_BASER_TYPE_VCPU] = "Virtual CPUs",
[GITS_BASER_TYPE_RESERVED3] = "Reserved (3)",
[GITS_BASER_TYPE_COLLECTION] = "Interrupt Collections",
[GITS_BASER_TYPE_RESERVED5] = "Reserved (5)",
[GITS_BASER_TYPE_RESERVED6] = "Reserved (6)",
[GITS_BASER_TYPE_RESERVED7] = "Reserved (7)",
};
static u64 its_read_baser(struct its_node *its, struct its_baser *baser)
{
u32 idx = baser - its->tables;
return gits_read_baser(its->base + GITS_BASER + (idx << 3));
}
static void its_write_baser(struct its_node *its, struct its_baser *baser,
u64 val)
{
u32 idx = baser - its->tables;
gits_write_baser(val, its->base + GITS_BASER + (idx << 3));
baser->val = its_read_baser(its, baser);
}
static int its_setup_baser(struct its_node *its, struct its_baser *baser,
u64 cache, u64 shr, u32 order, bool indirect)
{
u64 val = its_read_baser(its, baser);
u64 esz = GITS_BASER_ENTRY_SIZE(val);
u64 type = GITS_BASER_TYPE(val);
u64 baser_phys, tmp;
u32 alloc_pages, psz;
struct page *page;
void *base;
psz = baser->psz;
alloc_pages = (PAGE_ORDER_TO_SIZE(order) / psz);
if (alloc_pages > GITS_BASER_PAGES_MAX) {
pr_warn("ITS@%pa: %s too large, reduce ITS pages %u->%u\n",
&its->phys_base, its_base_type_string[type],
alloc_pages, GITS_BASER_PAGES_MAX);
alloc_pages = GITS_BASER_PAGES_MAX;
order = get_order(GITS_BASER_PAGES_MAX * psz);
}
page = alloc_pages_node(its->numa_node, GFP_KERNEL | __GFP_ZERO, order);
if (!page)
return -ENOMEM;
base = (void *)page_address(page);
baser_phys = virt_to_phys(base);
/* Check if the physical address of the memory is above 48bits */
if (IS_ENABLED(CONFIG_ARM64_64K_PAGES) && (baser_phys >> 48)) {
/* 52bit PA is supported only when PageSize=64K */
if (psz != SZ_64K) {
pr_err("ITS: no 52bit PA support when psz=%d\n", psz);
free_pages((unsigned long)base, order);
return -ENXIO;
}
/* Convert 52bit PA to 48bit field */
baser_phys = GITS_BASER_PHYS_52_to_48(baser_phys);
}
retry_baser:
val = (baser_phys |
(type << GITS_BASER_TYPE_SHIFT) |
((esz - 1) << GITS_BASER_ENTRY_SIZE_SHIFT) |
((alloc_pages - 1) << GITS_BASER_PAGES_SHIFT) |
cache |
shr |
GITS_BASER_VALID);
val |= indirect ? GITS_BASER_INDIRECT : 0x0;
switch (psz) {
case SZ_4K:
val |= GITS_BASER_PAGE_SIZE_4K;
break;
case SZ_16K:
val |= GITS_BASER_PAGE_SIZE_16K;
break;
case SZ_64K:
val |= GITS_BASER_PAGE_SIZE_64K;
break;
}
its_write_baser(its, baser, val);
tmp = baser->val;
if ((val ^ tmp) & GITS_BASER_SHAREABILITY_MASK) {
/*
* Shareability didn't stick. Just use
* whatever the read reported, which is likely
* to be the only thing this redistributor
* supports. If that's zero, make it
* non-cacheable as well.
*/
shr = tmp & GITS_BASER_SHAREABILITY_MASK;
if (!shr) {
cache = GITS_BASER_nC;
gic_flush_dcache_to_poc(base, PAGE_ORDER_TO_SIZE(order));
}
goto retry_baser;
}
if (val != tmp) {
pr_err("ITS@%pa: %s doesn't stick: %llx %llx\n",
&its->phys_base, its_base_type_string[type],
val, tmp);
free_pages((unsigned long)base, order);
return -ENXIO;
}
baser->order = order;
baser->base = base;
baser->psz = psz;
tmp = indirect ? GITS_LVL1_ENTRY_SIZE : esz;
pr_info("ITS@%pa: allocated %d %s @%lx (%s, esz %d, psz %dK, shr %d)\n",
&its->phys_base, (int)(PAGE_ORDER_TO_SIZE(order) / (int)tmp),
its_base_type_string[type],
(unsigned long)virt_to_phys(base),
indirect ? "indirect" : "flat", (int)esz,
psz / SZ_1K, (int)shr >> GITS_BASER_SHAREABILITY_SHIFT);
return 0;
}
static bool its_parse_indirect_baser(struct its_node *its,
struct its_baser *baser,
u32 *order, u32 ids)
{
u64 tmp = its_read_baser(its, baser);
u64 type = GITS_BASER_TYPE(tmp);
u64 esz = GITS_BASER_ENTRY_SIZE(tmp);
u64 val = GITS_BASER_InnerShareable | GITS_BASER_RaWaWb;
u32 new_order = *order;
u32 psz = baser->psz;
bool indirect = false;
/* No need to enable Indirection if memory requirement < (psz*2)bytes */
if ((esz << ids) > (psz * 2)) {
/*
* Find out whether hw supports a single or two-level table by
* table by reading bit at offset '62' after writing '1' to it.
*/
its_write_baser(its, baser, val | GITS_BASER_INDIRECT);
indirect = !!(baser->val & GITS_BASER_INDIRECT);
if (indirect) {
/*
* The size of the lvl2 table is equal to ITS page size
* which is 'psz'. For computing lvl1 table size,
* subtract ID bits that sparse lvl2 table from 'ids'
* which is reported by ITS hardware times lvl1 table
* entry size.
*/
ids -= ilog2(psz / (int)esz);
esz = GITS_LVL1_ENTRY_SIZE;
}
}
/*
* Allocate as many entries as required to fit the
* range of device IDs that the ITS can grok... The ID
* space being incredibly sparse, this results in a
* massive waste of memory if two-level device table
* feature is not supported by hardware.
*/
new_order = max_t(u32, get_order(esz << ids), new_order);
if (new_order >= MAX_ORDER) {
new_order = MAX_ORDER - 1;
ids = ilog2(PAGE_ORDER_TO_SIZE(new_order) / (int)esz);
pr_warn("ITS@%pa: %s Table too large, reduce ids %llu->%u\n",
&its->phys_base, its_base_type_string[type],
device_ids(its), ids);
}
*order = new_order;
return indirect;
}
static u32 compute_common_aff(u64 val)
{
u32 aff, clpiaff;
aff = FIELD_GET(GICR_TYPER_AFFINITY, val);
clpiaff = FIELD_GET(GICR_TYPER_COMMON_LPI_AFF, val);
return aff & ~(GENMASK(31, 0) >> (clpiaff * 8));
}
static u32 compute_its_aff(struct its_node *its)
{
u64 val;
u32 svpet;
/*
* Reencode the ITS SVPET and MPIDR as a GICR_TYPER, and compute
* the resulting affinity. We then use that to see if this match
* our own affinity.
*/
svpet = FIELD_GET(GITS_TYPER_SVPET, its->typer);
val = FIELD_PREP(GICR_TYPER_COMMON_LPI_AFF, svpet);
val |= FIELD_PREP(GICR_TYPER_AFFINITY, its->mpidr);
return compute_common_aff(val);
}
static struct its_node *find_sibling_its(struct its_node *cur_its)
{
struct its_node *its;
u32 aff;
if (!FIELD_GET(GITS_TYPER_SVPET, cur_its->typer))
return NULL;
aff = compute_its_aff(cur_its);
list_for_each_entry(its, &its_nodes, entry) {
u64 baser;
if (!is_v4_1(its) || its == cur_its)
continue;
if (!FIELD_GET(GITS_TYPER_SVPET, its->typer))
continue;
if (aff != compute_its_aff(its))
continue;
/* GICv4.1 guarantees that the vPE table is GITS_BASER2 */
baser = its->tables[2].val;
if (!(baser & GITS_BASER_VALID))
continue;
return its;
}
return NULL;
}
static void its_free_tables(struct its_node *its)
{
int i;
for (i = 0; i < GITS_BASER_NR_REGS; i++) {
if (its->tables[i].base) {
free_pages((unsigned long)its->tables[i].base,
its->tables[i].order);
its->tables[i].base = NULL;
}
}
}
static int its_probe_baser_psz(struct its_node *its, struct its_baser *baser)
{
u64 psz = SZ_64K;
while (psz) {
u64 val, gpsz;
val = its_read_baser(its, baser);
val &= ~GITS_BASER_PAGE_SIZE_MASK;
switch (psz) {
case SZ_64K:
gpsz = GITS_BASER_PAGE_SIZE_64K;
break;
case SZ_16K:
gpsz = GITS_BASER_PAGE_SIZE_16K;
break;
case SZ_4K:
default:
gpsz = GITS_BASER_PAGE_SIZE_4K;
break;
}
gpsz >>= GITS_BASER_PAGE_SIZE_SHIFT;
val |= FIELD_PREP(GITS_BASER_PAGE_SIZE_MASK, gpsz);
its_write_baser(its, baser, val);
if (FIELD_GET(GITS_BASER_PAGE_SIZE_MASK, baser->val) == gpsz)
break;
switch (psz) {
case SZ_64K:
psz = SZ_16K;
break;
case SZ_16K:
psz = SZ_4K;
break;
case SZ_4K:
default:
return -1;
}
}
baser->psz = psz;
return 0;
}
static int its_alloc_tables(struct its_node *its)
{
u64 shr = GITS_BASER_InnerShareable;
u64 cache = GITS_BASER_RaWaWb;
int err, i;
if (its->flags & ITS_FLAGS_WORKAROUND_CAVIUM_22375)
/* erratum 24313: ignore memory access type */
cache = GITS_BASER_nCnB;
for (i = 0; i < GITS_BASER_NR_REGS; i++) {
struct its_baser *baser = its->tables + i;
u64 val = its_read_baser(its, baser);
u64 type = GITS_BASER_TYPE(val);
bool indirect = false;
u32 order;
if (type == GITS_BASER_TYPE_NONE)
continue;
if (its_probe_baser_psz(its, baser)) {
its_free_tables(its);
return -ENXIO;
}
order = get_order(baser->psz);
switch (type) {
case GITS_BASER_TYPE_DEVICE:
indirect = its_parse_indirect_baser(its, baser, &order,
device_ids(its));
break;
case GITS_BASER_TYPE_VCPU:
if (is_v4_1(its)) {
struct its_node *sibling;
WARN_ON(i != 2);
if ((sibling = find_sibling_its(its))) {
*baser = sibling->tables[2];
its_write_baser(its, baser, baser->val);
continue;
}
}
indirect = its_parse_indirect_baser(its, baser, &order,
ITS_MAX_VPEID_BITS);
break;
}
err = its_setup_baser(its, baser, cache, shr, order, indirect);
if (err < 0) {
its_free_tables(its);
return err;
}
/* Update settings which will be used for next BASERn */
cache = baser->val & GITS_BASER_CACHEABILITY_MASK;
shr = baser->val & GITS_BASER_SHAREABILITY_MASK;
}
return 0;
}
static u64 inherit_vpe_l1_table_from_its(void)
{
struct its_node *its;
u64 val;
u32 aff;
val = gic_read_typer(gic_data_rdist_rd_base() + GICR_TYPER);
aff = compute_common_aff(val);
list_for_each_entry(its, &its_nodes, entry) {
u64 baser, addr;
if (!is_v4_1(its))
continue;
if (!FIELD_GET(GITS_TYPER_SVPET, its->typer))
continue;
if (aff != compute_its_aff(its))
continue;
/* GICv4.1 guarantees that the vPE table is GITS_BASER2 */
baser = its->tables[2].val;
if (!(baser & GITS_BASER_VALID))
continue;
/* We have a winner! */
gic_data_rdist()->vpe_l1_base = its->tables[2].base;
val = GICR_VPROPBASER_4_1_VALID;
if (baser & GITS_BASER_INDIRECT)
val |= GICR_VPROPBASER_4_1_INDIRECT;
val |= FIELD_PREP(GICR_VPROPBASER_4_1_PAGE_SIZE,
FIELD_GET(GITS_BASER_PAGE_SIZE_MASK, baser));
switch (FIELD_GET(GITS_BASER_PAGE_SIZE_MASK, baser)) {
case GIC_PAGE_SIZE_64K:
addr = GITS_BASER_ADDR_48_to_52(baser);
break;
default:
addr = baser & GENMASK_ULL(47, 12);
break;
}
val |= FIELD_PREP(GICR_VPROPBASER_4_1_ADDR, addr >> 12);
val |= FIELD_PREP(GICR_VPROPBASER_SHAREABILITY_MASK,
FIELD_GET(GITS_BASER_SHAREABILITY_MASK, baser));
val |= FIELD_PREP(GICR_VPROPBASER_INNER_CACHEABILITY_MASK,
FIELD_GET(GITS_BASER_INNER_CACHEABILITY_MASK, baser));
val |= FIELD_PREP(GICR_VPROPBASER_4_1_SIZE, GITS_BASER_NR_PAGES(baser) - 1);
return val;
}
return 0;
}
static u64 inherit_vpe_l1_table_from_rd(cpumask_t **mask)
{
u32 aff;
u64 val;
int cpu;
val = gic_read_typer(gic_data_rdist_rd_base() + GICR_TYPER);
aff = compute_common_aff(val);
for_each_possible_cpu(cpu) {
void __iomem *base = gic_data_rdist_cpu(cpu)->rd_base;
if (!base || cpu == smp_processor_id())
continue;
val = gic_read_typer(base + GICR_TYPER);
if (aff != compute_common_aff(val))
continue;
/*
* At this point, we have a victim. This particular CPU
* has already booted, and has an affinity that matches
* ours wrt CommonLPIAff. Let's use its own VPROPBASER.
* Make sure we don't write the Z bit in that case.
*/
val = gicr_read_vpropbaser(base + SZ_128K + GICR_VPROPBASER);
val &= ~GICR_VPROPBASER_4_1_Z;
gic_data_rdist()->vpe_l1_base = gic_data_rdist_cpu(cpu)->vpe_l1_base;
*mask = gic_data_rdist_cpu(cpu)->vpe_table_mask;
return val;
}
return 0;
}
static bool allocate_vpe_l2_table(int cpu, u32 id)
{
void __iomem *base = gic_data_rdist_cpu(cpu)->rd_base;
unsigned int psz, esz, idx, npg, gpsz;
u64 val;
struct page *page;
__le64 *table;
if (!gic_rdists->has_rvpeid)
return true;
/* Skip non-present CPUs */
if (!base)
return true;
val = gicr_read_vpropbaser(base + SZ_128K + GICR_VPROPBASER);
esz = FIELD_GET(GICR_VPROPBASER_4_1_ENTRY_SIZE, val) + 1;
gpsz = FIELD_GET(GICR_VPROPBASER_4_1_PAGE_SIZE, val);
npg = FIELD_GET(GICR_VPROPBASER_4_1_SIZE, val) + 1;
switch (gpsz) {
default:
WARN_ON(1);
fallthrough;
case GIC_PAGE_SIZE_4K:
psz = SZ_4K;
break;
case GIC_PAGE_SIZE_16K:
psz = SZ_16K;
break;
case GIC_PAGE_SIZE_64K:
psz = SZ_64K;
break;
}
/* Don't allow vpe_id that exceeds single, flat table limit */
if (!(val & GICR_VPROPBASER_4_1_INDIRECT))
return (id < (npg * psz / (esz * SZ_8)));
/* Compute 1st level table index & check if that exceeds table limit */
idx = id >> ilog2(psz / (esz * SZ_8));
if (idx >= (npg * psz / GITS_LVL1_ENTRY_SIZE))
return false;
table = gic_data_rdist_cpu(cpu)->vpe_l1_base;
/* Allocate memory for 2nd level table */
if (!table[idx]) {
page = alloc_pages(GFP_KERNEL | __GFP_ZERO, get_order(psz));
if (!page)
return false;
/* Flush Lvl2 table to PoC if hw doesn't support coherency */
if (!(val & GICR_VPROPBASER_SHAREABILITY_MASK))
gic_flush_dcache_to_poc(page_address(page), psz);
table[idx] = cpu_to_le64(page_to_phys(page) | GITS_BASER_VALID);
/* Flush Lvl1 entry to PoC if hw doesn't support coherency */
if (!(val & GICR_VPROPBASER_SHAREABILITY_MASK))
gic_flush_dcache_to_poc(table + idx, GITS_LVL1_ENTRY_SIZE);
/* Ensure updated table contents are visible to RD hardware */
dsb(sy);
}
return true;
}
static int allocate_vpe_l1_table(void)
{
void __iomem *vlpi_base = gic_data_rdist_vlpi_base();
u64 val, gpsz, npg, pa;
unsigned int psz = SZ_64K;
unsigned int np, epp, esz;
struct page *page;
if (!gic_rdists->has_rvpeid)
return 0;
/*
* if VPENDBASER.Valid is set, disable any previously programmed
* VPE by setting PendingLast while clearing Valid. This has the
* effect of making sure no doorbell will be generated and we can
* then safely clear VPROPBASER.Valid.
*/
if (gicr_read_vpendbaser(vlpi_base + GICR_VPENDBASER) & GICR_VPENDBASER_Valid)
gicr_write_vpendbaser(GICR_VPENDBASER_PendingLast,
vlpi_base + GICR_VPENDBASER);
/*
* If we can inherit the configuration from another RD, let's do
* so. Otherwise, we have to go through the allocation process. We
* assume that all RDs have the exact same requirements, as
* nothing will work otherwise.
*/
val = inherit_vpe_l1_table_from_rd(&gic_data_rdist()->vpe_table_mask);
if (val & GICR_VPROPBASER_4_1_VALID)
goto out;
gic_data_rdist()->vpe_table_mask = kzalloc(sizeof(cpumask_t), GFP_ATOMIC);
if (!gic_data_rdist()->vpe_table_mask)
return -ENOMEM;
val = inherit_vpe_l1_table_from_its();
if (val & GICR_VPROPBASER_4_1_VALID)
goto out;
/* First probe the page size */
val = FIELD_PREP(GICR_VPROPBASER_4_1_PAGE_SIZE, GIC_PAGE_SIZE_64K);
gicr_write_vpropbaser(val, vlpi_base + GICR_VPROPBASER);
val = gicr_read_vpropbaser(vlpi_base + GICR_VPROPBASER);
gpsz = FIELD_GET(GICR_VPROPBASER_4_1_PAGE_SIZE, val);
esz = FIELD_GET(GICR_VPROPBASER_4_1_ENTRY_SIZE, val);
switch (gpsz) {
default:
gpsz = GIC_PAGE_SIZE_4K;
fallthrough;
case GIC_PAGE_SIZE_4K:
psz = SZ_4K;
break;
case GIC_PAGE_SIZE_16K:
psz = SZ_16K;
break;
case GIC_PAGE_SIZE_64K:
psz = SZ_64K;
break;
}
/*
* Start populating the register from scratch, including RO fields
* (which we want to print in debug cases...)
*/
val = 0;
val |= FIELD_PREP(GICR_VPROPBASER_4_1_PAGE_SIZE, gpsz);
val |= FIELD_PREP(GICR_VPROPBASER_4_1_ENTRY_SIZE, esz);
/* How many entries per GIC page? */
esz++;
epp = psz / (esz * SZ_8);
/*
* If we need more than just a single L1 page, flag the table
* as indirect and compute the number of required L1 pages.
*/
if (epp < ITS_MAX_VPEID) {
int nl2;
val |= GICR_VPROPBASER_4_1_INDIRECT;
/* Number of L2 pages required to cover the VPEID space */
nl2 = DIV_ROUND_UP(ITS_MAX_VPEID, epp);
/* Number of L1 pages to point to the L2 pages */
npg = DIV_ROUND_UP(nl2 * SZ_8, psz);
} else {
npg = 1;
}
val |= FIELD_PREP(GICR_VPROPBASER_4_1_SIZE, npg - 1);
/* Right, that's the number of CPU pages we need for L1 */
np = DIV_ROUND_UP(npg * psz, PAGE_SIZE);
pr_debug("np = %d, npg = %lld, psz = %d, epp = %d, esz = %d\n",
np, npg, psz, epp, esz);
page = alloc_pages(GFP_ATOMIC | __GFP_ZERO, get_order(np * PAGE_SIZE));
if (!page)
return -ENOMEM;
gic_data_rdist()->vpe_l1_base = page_address(page);
pa = virt_to_phys(page_address(page));
WARN_ON(!IS_ALIGNED(pa, psz));
val |= FIELD_PREP(GICR_VPROPBASER_4_1_ADDR, pa >> 12);
val |= GICR_VPROPBASER_RaWb;
val |= GICR_VPROPBASER_InnerShareable;
val |= GICR_VPROPBASER_4_1_Z;
val |= GICR_VPROPBASER_4_1_VALID;
out:
gicr_write_vpropbaser(val, vlpi_base + GICR_VPROPBASER);
cpumask_set_cpu(smp_processor_id(), gic_data_rdist()->vpe_table_mask);
pr_debug("CPU%d: VPROPBASER = %llx %*pbl\n",
smp_processor_id(), val,
cpumask_pr_args(gic_data_rdist()->vpe_table_mask));
return 0;
}
static int its_alloc_collections(struct its_node *its)
{
int i;
its->collections = kcalloc(nr_cpu_ids, sizeof(*its->collections),
GFP_KERNEL);
if (!its->collections)
return -ENOMEM;
for (i = 0; i < nr_cpu_ids; i++)
its->collections[i].target_address = ~0ULL;
return 0;
}
static struct page *its_allocate_pending_table(gfp_t gfp_flags)
{
struct page *pend_page;
pend_page = alloc_pages(gfp_flags | __GFP_ZERO,
get_order(LPI_PENDBASE_SZ));
if (!pend_page)
return NULL;
/* Make sure the GIC will observe the zero-ed page */
gic_flush_dcache_to_poc(page_address(pend_page), LPI_PENDBASE_SZ);
return pend_page;
}
static void its_free_pending_table(struct page *pt)
{
free_pages((unsigned long)page_address(pt), get_order(LPI_PENDBASE_SZ));
}
/*
* Booting with kdump and LPIs enabled is generally fine. Any other
* case is wrong in the absence of firmware/EFI support.
*/
static bool enabled_lpis_allowed(void)
{
phys_addr_t addr;
u64 val;
/* Check whether the property table is in a reserved region */
val = gicr_read_propbaser(gic_data_rdist_rd_base() + GICR_PROPBASER);
addr = val & GENMASK_ULL(51, 12);
return gic_check_reserved_range(addr, LPI_PROPBASE_SZ);
}
static int __init allocate_lpi_tables(void)
{
u64 val;
int err, cpu;
/*
* If LPIs are enabled while we run this from the boot CPU,
* flag the RD tables as pre-allocated if the stars do align.
*/
val = readl_relaxed(gic_data_rdist_rd_base() + GICR_CTLR);
if ((val & GICR_CTLR_ENABLE_LPIS) && enabled_lpis_allowed()) {
gic_rdists->flags |= (RDIST_FLAGS_RD_TABLES_PREALLOCATED |
RDIST_FLAGS_PROPBASE_NEEDS_FLUSHING);
pr_info("GICv3: Using preallocated redistributor tables\n");
}
err = its_setup_lpi_prop_table();
if (err)
return err;
/*
* We allocate all the pending tables anyway, as we may have a
* mix of RDs that have had LPIs enabled, and some that
* don't. We'll free the unused ones as each CPU comes online.
*/
for_each_possible_cpu(cpu) {
struct page *pend_page;
pend_page = its_allocate_pending_table(GFP_NOWAIT);
if (!pend_page) {
pr_err("Failed to allocate PENDBASE for CPU%d\n", cpu);
return -ENOMEM;
}
gic_data_rdist_cpu(cpu)->pend_page = pend_page;
}
return 0;
}
static u64 read_vpend_dirty_clear(void __iomem *vlpi_base)
{
u32 count = 1000000; /* 1s! */
bool clean;
u64 val;
do {
val = gicr_read_vpendbaser(vlpi_base + GICR_VPENDBASER);
clean = !(val & GICR_VPENDBASER_Dirty);
if (!clean) {
count--;
cpu_relax();
udelay(1);
}
} while (!clean && count);
if (unlikely(!clean))
pr_err_ratelimited("ITS virtual pending table not cleaning\n");
return val;
}
static u64 its_clear_vpend_valid(void __iomem *vlpi_base, u64 clr, u64 set)
{
u64 val;
/* Make sure we wait until the RD is done with the initial scan */
val = read_vpend_dirty_clear(vlpi_base);
val &= ~GICR_VPENDBASER_Valid;
val &= ~clr;
val |= set;
gicr_write_vpendbaser(val, vlpi_base + GICR_VPENDBASER);
val = read_vpend_dirty_clear(vlpi_base);
if (unlikely(val & GICR_VPENDBASER_Dirty))
val |= GICR_VPENDBASER_PendingLast;
return val;
}
static void its_cpu_init_lpis(void)
{
void __iomem *rbase = gic_data_rdist_rd_base();
struct page *pend_page;
phys_addr_t paddr;
u64 val, tmp;
if (gic_data_rdist()->flags & RD_LOCAL_LPI_ENABLED)
return;
val = readl_relaxed(rbase + GICR_CTLR);
if ((gic_rdists->flags & RDIST_FLAGS_RD_TABLES_PREALLOCATED) &&
(val & GICR_CTLR_ENABLE_LPIS)) {
/*
* Check that we get the same property table on all
* RDs. If we don't, this is hopeless.
*/
paddr = gicr_read_propbaser(rbase + GICR_PROPBASER);
paddr &= GENMASK_ULL(51, 12);
if (WARN_ON(gic_rdists->prop_table_pa != paddr))
add_taint(TAINT_CRAP, LOCKDEP_STILL_OK);
paddr = gicr_read_pendbaser(rbase + GICR_PENDBASER);
paddr &= GENMASK_ULL(51, 16);
WARN_ON(!gic_check_reserved_range(paddr, LPI_PENDBASE_SZ));
gic_data_rdist()->flags |= RD_LOCAL_PENDTABLE_PREALLOCATED;
goto out;
}
pend_page = gic_data_rdist()->pend_page;
paddr = page_to_phys(pend_page);
/* set PROPBASE */
val = (gic_rdists->prop_table_pa |
GICR_PROPBASER_InnerShareable |
GICR_PROPBASER_RaWaWb |
((LPI_NRBITS - 1) & GICR_PROPBASER_IDBITS_MASK));
gicr_write_propbaser(val, rbase + GICR_PROPBASER);
tmp = gicr_read_propbaser(rbase + GICR_PROPBASER);
if ((tmp ^ val) & GICR_PROPBASER_SHAREABILITY_MASK) {
if (!(tmp & GICR_PROPBASER_SHAREABILITY_MASK)) {
/*
* The HW reports non-shareable, we must
* remove the cacheability attributes as
* well.
*/
val &= ~(GICR_PROPBASER_SHAREABILITY_MASK |
GICR_PROPBASER_CACHEABILITY_MASK);
val |= GICR_PROPBASER_nC;
gicr_write_propbaser(val, rbase + GICR_PROPBASER);
}
pr_info_once("GIC: using cache flushing for LPI property table\n");
gic_rdists->flags |= RDIST_FLAGS_PROPBASE_NEEDS_FLUSHING;
}
/* set PENDBASE */
val = (page_to_phys(pend_page) |
GICR_PENDBASER_InnerShareable |
GICR_PENDBASER_RaWaWb);
gicr_write_pendbaser(val, rbase + GICR_PENDBASER);
tmp = gicr_read_pendbaser(rbase + GICR_PENDBASER);
if (!(tmp & GICR_PENDBASER_SHAREABILITY_MASK)) {
/*
* The HW reports non-shareable, we must remove the
* cacheability attributes as well.
*/
val &= ~(GICR_PENDBASER_SHAREABILITY_MASK |
GICR_PENDBASER_CACHEABILITY_MASK);
val |= GICR_PENDBASER_nC;
gicr_write_pendbaser(val, rbase + GICR_PENDBASER);
}
/* Enable LPIs */
val = readl_relaxed(rbase + GICR_CTLR);
val |= GICR_CTLR_ENABLE_LPIS;
writel_relaxed(val, rbase + GICR_CTLR);
if (gic_rdists->has_vlpis && !gic_rdists->has_rvpeid) {
void __iomem *vlpi_base = gic_data_rdist_vlpi_base();
/*
* It's possible for CPU to receive VLPIs before it is
* scheduled as a vPE, especially for the first CPU, and the
* VLPI with INTID larger than 2^(IDbits+1) will be considered
* as out of range and dropped by GIC.
* So we initialize IDbits to known value to avoid VLPI drop.
*/
val = (LPI_NRBITS - 1) & GICR_VPROPBASER_IDBITS_MASK;
pr_debug("GICv4: CPU%d: Init IDbits to 0x%llx for GICR_VPROPBASER\n",
smp_processor_id(), val);
gicr_write_vpropbaser(val, vlpi_base + GICR_VPROPBASER);
/*
* Also clear Valid bit of GICR_VPENDBASER, in case some
* ancient programming gets left in and has possibility of
* corrupting memory.
*/
val = its_clear_vpend_valid(vlpi_base, 0, 0);
}
if (allocate_vpe_l1_table()) {
/*
* If the allocation has failed, we're in massive trouble.
* Disable direct injection, and pray that no VM was
* already running...
*/
gic_rdists->has_rvpeid = false;
gic_rdists->has_vlpis = false;
}
/* Make sure the GIC has seen the above */
dsb(sy);
out:
gic_data_rdist()->flags |= RD_LOCAL_LPI_ENABLED;
pr_info("GICv3: CPU%d: using %s LPI pending table @%pa\n",
smp_processor_id(),
gic_data_rdist()->flags & RD_LOCAL_PENDTABLE_PREALLOCATED ?
"reserved" : "allocated",
&paddr);
}
static void its_cpu_init_collection(struct its_node *its)
{
int cpu = smp_processor_id();
u64 target;
/* avoid cross node collections and its mapping */
if (its->flags & ITS_FLAGS_WORKAROUND_CAVIUM_23144) {
struct device_node *cpu_node;