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/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* Copyright 2016-17 IBM Corp.
*/
#ifndef _VAS_H
#define _VAS_H
#include <linux/atomic.h>
#include <linux/idr.h>
#include <asm/vas.h>
#include <linux/io.h>
#include <linux/dcache.h>
#include <linux/mutex.h>
#include <linux/stringify.h>
/*
* Overview of Virtual Accelerator Switchboard (VAS).
*
* VAS is a hardware "switchboard" that allows senders and receivers to
* exchange messages with _minimal_ kernel involvment. The receivers are
* typically NX coprocessor engines that perform compression or encryption
* in hardware, but receivers can also be other software threads.
*
* Senders are user/kernel threads that submit compression/encryption or
* other requests to the receivers. Senders must format their messages as
* Coprocessor Request Blocks (CRB)s and submit them using the "copy" and
* "paste" instructions which were introduced in Power9.
*
* A Power node can have (upto?) 8 Power chips. There is one instance of
* VAS in each Power9 chip. Each instance of VAS has 64K windows or ports,
* Senders and receivers must each connect to a separate window before they
* can exchange messages through the switchboard.
*
* Each window is described by two types of window contexts:
*
* Hypervisor Window Context (HVWC) of size VAS_HVWC_SIZE bytes
*
* OS/User Window Context (UWC) of size VAS_UWC_SIZE bytes.
*
* A window context can be viewed as a set of 64-bit registers. The settings
* in these registers configure/control/determine the behavior of the VAS
* hardware when messages are sent/received through the window. The registers
* in the HVWC are configured by the kernel while the registers in the UWC can
* be configured by the kernel or by the user space application that is using
* the window.
*
* The HVWCs for all windows on a specific instance of VAS are in a contiguous
* range of hardware addresses or Base address region (BAR) referred to as the
* HVWC BAR for the instance. Similarly the UWCs for all windows on an instance
* are referred to as the UWC BAR for the instance.
*
* The two BARs for each instance are defined Power9 MMIO Ranges spreadsheet
* and available to the kernel in the VAS node's "reg" property in the device
* tree:
*
* /proc/device-tree/vasm@.../reg
*
* (see vas_probe() for details on the reg property).
*
* The kernel maps the HVWC and UWC BAR regions into the kernel address
* space (hvwc_map and uwc_map). The kernel can then access the window
* contexts of a specific window using:
*
* hvwc = hvwc_map + winid * VAS_HVWC_SIZE.
* uwc = uwc_map + winid * VAS_UWC_SIZE.
*
* where winid is the window index (0..64K).
*
* As mentioned, a window context is used to "configure" a window. Besides
* this configuration address, each _send_ window also has a unique hardware
* "paste" address that is used to submit requests/CRBs (see vas_paste_crb()).
*
* The hardware paste address for a window is computed using the "paste
* base address" and "paste win id shift" reg properties in the VAS device
* tree node using:
*
* paste_addr = paste_base + ((winid << paste_win_id_shift))
*
* (again, see vas_probe() for ->paste_base_addr and ->paste_win_id_shift).
*
* The kernel maps this hardware address into the sender's address space
* after which they can use the 'paste' instruction (new in Power9) to
* send a message (submit a request aka CRB) to the coprocessor.
*
* NOTE: In the initial version, senders can only in-kernel drivers/threads.
* Support for user space threads will be added in follow-on patches.
*
* TODO: Do we need to map the UWC into user address space so they can return
* credits? Its NA for NX but may be needed for other receive windows.
*
*/
#define VAS_WINDOWS_PER_CHIP (64 << 10)
/*
* Hypervisor and OS/USer Window Context sizes
*/
#define VAS_HVWC_SIZE 512
#define VAS_UWC_SIZE PAGE_SIZE
/*
* Initial per-process credits.
* Max send window credits: 4K-1 (12-bits in VAS_TX_WCRED)
*
* TODO: Needs tuning for per-process credits
*/
#define VAS_TX_WCREDS_MAX ((4 << 10) - 1)
#define VAS_WCREDS_DEFAULT (1 << 10)
/*
* VAS Window Context Register Offsets and bitmasks.
* See Section 3.1.4 of VAS Work book
*/
#define VAS_LPID_OFFSET 0x010
#define VAS_LPID PPC_BITMASK(0, 11)
#define VAS_PID_OFFSET 0x018
#define VAS_PID_ID PPC_BITMASK(0, 19)
#define VAS_XLATE_MSR_OFFSET 0x020
#define VAS_XLATE_MSR_DR PPC_BIT(0)
#define VAS_XLATE_MSR_TA PPC_BIT(1)
#define VAS_XLATE_MSR_PR PPC_BIT(2)
#define VAS_XLATE_MSR_US PPC_BIT(3)
#define VAS_XLATE_MSR_HV PPC_BIT(4)
#define VAS_XLATE_MSR_SF PPC_BIT(5)
#define VAS_XLATE_LPCR_OFFSET 0x028
#define VAS_XLATE_LPCR_PAGE_SIZE PPC_BITMASK(0, 2)
#define VAS_XLATE_LPCR_ISL PPC_BIT(3)
#define VAS_XLATE_LPCR_TC PPC_BIT(4)
#define VAS_XLATE_LPCR_SC PPC_BIT(5)
#define VAS_XLATE_CTL_OFFSET 0x030
#define VAS_XLATE_MODE PPC_BITMASK(0, 1)
#define VAS_AMR_OFFSET 0x040
#define VAS_AMR PPC_BITMASK(0, 63)
#define VAS_SEIDR_OFFSET 0x048
#define VAS_SEIDR PPC_BITMASK(0, 63)
#define VAS_FAULT_TX_WIN_OFFSET 0x050
#define VAS_FAULT_TX_WIN PPC_BITMASK(48, 63)
#define VAS_OSU_INTR_SRC_RA_OFFSET 0x060
#define VAS_OSU_INTR_SRC_RA PPC_BITMASK(8, 63)
#define VAS_HV_INTR_SRC_RA_OFFSET 0x070
#define VAS_HV_INTR_SRC_RA PPC_BITMASK(8, 63)
#define VAS_PSWID_OFFSET 0x078
#define VAS_PSWID_EA_HANDLE PPC_BITMASK(0, 31)
#define VAS_SPARE1_OFFSET 0x080
#define VAS_SPARE2_OFFSET 0x088
#define VAS_SPARE3_OFFSET 0x090
#define VAS_SPARE4_OFFSET 0x130
#define VAS_SPARE5_OFFSET 0x160
#define VAS_SPARE6_OFFSET 0x188
#define VAS_LFIFO_BAR_OFFSET 0x0A0
#define VAS_LFIFO_BAR PPC_BITMASK(8, 53)
#define VAS_PAGE_MIGRATION_SELECT PPC_BITMASK(54, 56)
#define VAS_LDATA_STAMP_CTL_OFFSET 0x0A8
#define VAS_LDATA_STAMP PPC_BITMASK(0, 1)
#define VAS_XTRA_WRITE PPC_BIT(2)
#define VAS_LDMA_CACHE_CTL_OFFSET 0x0B0
#define VAS_LDMA_TYPE PPC_BITMASK(0, 1)
#define VAS_LDMA_FIFO_DISABLE PPC_BIT(2)
#define VAS_LRFIFO_PUSH_OFFSET 0x0B8
#define VAS_LRFIFO_PUSH PPC_BITMASK(0, 15)
#define VAS_CURR_MSG_COUNT_OFFSET 0x0C0
#define VAS_CURR_MSG_COUNT PPC_BITMASK(0, 7)
#define VAS_LNOTIFY_AFTER_COUNT_OFFSET 0x0C8
#define VAS_LNOTIFY_AFTER_COUNT PPC_BITMASK(0, 7)
#define VAS_LRX_WCRED_OFFSET 0x0E0
#define VAS_LRX_WCRED PPC_BITMASK(0, 15)
#define VAS_LRX_WCRED_ADDER_OFFSET 0x190
#define VAS_LRX_WCRED_ADDER PPC_BITMASK(0, 15)
#define VAS_TX_WCRED_OFFSET 0x0F0
#define VAS_TX_WCRED PPC_BITMASK(4, 15)
#define VAS_TX_WCRED_ADDER_OFFSET 0x1A0
#define VAS_TX_WCRED_ADDER PPC_BITMASK(4, 15)
#define VAS_LFIFO_SIZE_OFFSET 0x100
#define VAS_LFIFO_SIZE PPC_BITMASK(0, 3)
#define VAS_WINCTL_OFFSET 0x108
#define VAS_WINCTL_OPEN PPC_BIT(0)
#define VAS_WINCTL_REJ_NO_CREDIT PPC_BIT(1)
#define VAS_WINCTL_PIN PPC_BIT(2)
#define VAS_WINCTL_TX_WCRED_MODE PPC_BIT(3)
#define VAS_WINCTL_RX_WCRED_MODE PPC_BIT(4)
#define VAS_WINCTL_TX_WORD_MODE PPC_BIT(5)
#define VAS_WINCTL_RX_WORD_MODE PPC_BIT(6)
#define VAS_WINCTL_RSVD_TXBUF PPC_BIT(7)
#define VAS_WINCTL_THRESH_CTL PPC_BITMASK(8, 9)
#define VAS_WINCTL_FAULT_WIN PPC_BIT(10)
#define VAS_WINCTL_NX_WIN PPC_BIT(11)
#define VAS_WIN_STATUS_OFFSET 0x110
#define VAS_WIN_BUSY PPC_BIT(1)
#define VAS_WIN_CTX_CACHING_CTL_OFFSET 0x118
#define VAS_CASTOUT_REQ PPC_BIT(0)
#define VAS_PUSH_TO_MEM PPC_BIT(1)
#define VAS_WIN_CACHE_STATUS PPC_BIT(4)
#define VAS_TX_RSVD_BUF_COUNT_OFFSET 0x120
#define VAS_RXVD_BUF_COUNT PPC_BITMASK(58, 63)
#define VAS_LRFIFO_WIN_PTR_OFFSET 0x128
#define VAS_LRX_WIN_ID PPC_BITMASK(0, 15)
/*
* Local Notification Control Register controls what happens in _response_
* to a paste command and hence applies only to receive windows.
*/
#define VAS_LNOTIFY_CTL_OFFSET 0x138
#define VAS_NOTIFY_DISABLE PPC_BIT(0)
#define VAS_INTR_DISABLE PPC_BIT(1)
#define VAS_NOTIFY_EARLY PPC_BIT(2)
#define VAS_NOTIFY_OSU_INTR PPC_BIT(3)
#define VAS_LNOTIFY_PID_OFFSET 0x140
#define VAS_LNOTIFY_PID PPC_BITMASK(0, 19)
#define VAS_LNOTIFY_LPID_OFFSET 0x148
#define VAS_LNOTIFY_LPID PPC_BITMASK(0, 11)
#define VAS_LNOTIFY_TID_OFFSET 0x150
#define VAS_LNOTIFY_TID PPC_BITMASK(0, 15)
#define VAS_LNOTIFY_SCOPE_OFFSET 0x158
#define VAS_LNOTIFY_MIN_SCOPE PPC_BITMASK(0, 1)
#define VAS_LNOTIFY_MAX_SCOPE PPC_BITMASK(2, 3)
#define VAS_NX_UTIL_OFFSET 0x1B0
#define VAS_NX_UTIL PPC_BITMASK(0, 63)
/* SE: Side effects */
#define VAS_NX_UTIL_SE_OFFSET 0x1B8
#define VAS_NX_UTIL_SE PPC_BITMASK(0, 63)
#define VAS_NX_UTIL_ADDER_OFFSET 0x180
#define VAS_NX_UTIL_ADDER PPC_BITMASK(32, 63)
/*
* VREG(x):
* Expand a register's short name (eg: LPID) into two parameters:
* - the register's short name in string form ("LPID"), and
* - the name of the macro (eg: VAS_LPID_OFFSET), defining the
* register's offset in the window context
*/
#define VREG_SFX(n, s) __stringify(n), VAS_##n##s
#define VREG(r) VREG_SFX(r, _OFFSET)
/*
* Local Notify Scope Control Register. (Receive windows only).
*/
enum vas_notify_scope {
VAS_SCOPE_LOCAL,
VAS_SCOPE_GROUP,
VAS_SCOPE_VECTORED_GROUP,
VAS_SCOPE_UNUSED,
};
/*
* Local DMA Cache Control Register (Receive windows only).
*/
enum vas_dma_type {
VAS_DMA_TYPE_INJECT,
VAS_DMA_TYPE_WRITE,
};
/*
* Local Notify Scope Control Register. (Receive windows only).
* Not applicable to NX receive windows.
*/
enum vas_notify_after_count {
VAS_NOTIFY_AFTER_256 = 0,
VAS_NOTIFY_NONE,
VAS_NOTIFY_AFTER_2
};
/*
* NX can generate an interrupt for multiple faults and expects kernel
* to process all of them. So read all valid CRB entries until find the
* invalid one. So use pswid which is pasted by NX and ccw[0] (reserved
* bit in BE) to check valid CRB. CCW[0] will not be touched by user
* space. Application gets CRB formt error if it updates this bit.
*
* Invalidate FIFO during allocation and process all entries from last
* successful read until finds invalid pswid and ccw[0] values.
* After reading each CRB entry from fault FIFO, the kernel invalidate
* it by updating pswid with FIFO_INVALID_ENTRY and CCW[0] with
* CCW0_INVALID.
*/
#define FIFO_INVALID_ENTRY 0xffffffff
#define CCW0_INVALID 1
/*
* One per instance of VAS. Each instance will have a separate set of
* receive windows, one per coprocessor type.
*
* See also function header of set_vinst_win() for details on ->windows[]
* and ->rxwin[] tables.
*/
struct vas_instance {
int vas_id;
struct ida ida;
struct list_head node;
struct platform_device *pdev;
u64 hvwc_bar_start;
u64 uwc_bar_start;
u64 paste_base_addr;
u64 paste_win_id_shift;
u64 irq_port;
int virq;
int fault_crbs;
int fault_fifo_size;
int fifo_in_progress; /* To wake up thread or return IRQ_HANDLED */
spinlock_t fault_lock; /* Protects fifo_in_progress update */
void *fault_fifo;
struct pnv_vas_window *fault_win; /* Fault window */
struct mutex mutex;
struct pnv_vas_window *rxwin[VAS_COP_TYPE_MAX];
struct pnv_vas_window *windows[VAS_WINDOWS_PER_CHIP];
char *name;
char *dbgname;
struct dentry *dbgdir;
};
/*
* In-kernel state a VAS window on PowerNV. One per window.
*/
struct pnv_vas_window {
struct vas_window vas_win;
/* Fields common to send and receive windows */
struct vas_instance *vinst;
bool tx_win; /* True if send window */
bool nx_win; /* True if NX window */
bool user_win; /* True if user space window */
void *hvwc_map; /* HV window context */
void *uwc_map; /* OS/User window context */
/* Fields applicable only to send windows */
void *paste_kaddr;
char *paste_addr_name;
struct pnv_vas_window *rxwin;
/* Fields applicable only to receive windows */
atomic_t num_txwins;
};
/*
* Container for the hardware state of a window. One per-window.
*
* A VAS Window context is a 512-byte area in the hardware that contains
* a set of 64-bit registers. Individual bit-fields in these registers
* determine the configuration/operation of the hardware. struct vas_winctx
* is a container for the register fields in the window context.
*/
struct vas_winctx {
void *rx_fifo;
int rx_fifo_size;
int wcreds_max;
int rsvd_txbuf_count;
bool user_win;
bool nx_win;
bool fault_win;
bool rsvd_txbuf_enable;
bool pin_win;
bool rej_no_credit;
bool tx_wcred_mode;
bool rx_wcred_mode;
bool tx_word_mode;
bool rx_word_mode;
bool data_stamp;
bool xtra_write;
bool notify_disable;
bool intr_disable;
bool fifo_disable;
bool notify_early;
bool notify_os_intr_reg;
int lpid;
int pidr; /* value from SPRN_PID, not linux pid */
int lnotify_lpid;
int lnotify_pid;
int lnotify_tid;
u32 pswid;
int rx_win_id;
int fault_win_id;
int tc_mode;
u64 irq_port;
enum vas_dma_type dma_type;
enum vas_notify_scope min_scope;
enum vas_notify_scope max_scope;
enum vas_notify_after_count notify_after_count;
};
extern struct mutex vas_mutex;
extern struct vas_instance *find_vas_instance(int vasid);
extern void vas_init_dbgdir(void);
extern void vas_instance_init_dbgdir(struct vas_instance *vinst);
extern void vas_window_init_dbgdir(struct pnv_vas_window *win);
extern void vas_window_free_dbgdir(struct pnv_vas_window *win);
extern int vas_setup_fault_window(struct vas_instance *vinst);
extern irqreturn_t vas_fault_thread_fn(int irq, void *data);
extern irqreturn_t vas_fault_handler(int irq, void *dev_id);
extern void vas_return_credit(struct pnv_vas_window *window, bool tx);
extern struct pnv_vas_window *vas_pswid_to_window(struct vas_instance *vinst,
uint32_t pswid);
extern void vas_win_paste_addr(struct pnv_vas_window *window, u64 *addr,
int *len);
static inline int vas_window_pid(struct vas_window *window)
{
return pid_vnr(window->task_ref.pid);
}
static inline void vas_log_write(struct pnv_vas_window *win, char *name,
void *regptr, u64 val)
{
if (val)
pr_debug("%swin #%d: %s reg %p, val 0x%016llx\n",
win->tx_win ? "Tx" : "Rx", win->vas_win.winid,
name, regptr, val);
}
static inline void write_uwc_reg(struct pnv_vas_window *win, char *name,
s32 reg, u64 val)
{
void *regptr;
regptr = win->uwc_map + reg;
vas_log_write(win, name, regptr, val);
out_be64(regptr, val);
}
static inline void write_hvwc_reg(struct pnv_vas_window *win, char *name,
s32 reg, u64 val)
{
void *regptr;
regptr = win->hvwc_map + reg;
vas_log_write(win, name, regptr, val);
out_be64(regptr, val);
}
static inline u64 read_hvwc_reg(struct pnv_vas_window *win,
char *name __maybe_unused, s32 reg)
{
return in_be64(win->hvwc_map+reg);
}
/*
* Encode/decode the Partition Send Window ID (PSWID) for a window in
* a way that we can uniquely identify any window in the system. i.e.
* we should be able to locate the 'struct vas_window' given the PSWID.
*
* Bits Usage
* 0:7 VAS id (8 bits)
* 8:15 Unused, 0 (3 bits)
* 16:31 Window id (16 bits)
*/
static inline u32 encode_pswid(int vasid, int winid)
{
return ((u32)winid | (vasid << (31 - 7)));
}
static inline void decode_pswid(u32 pswid, int *vasid, int *winid)
{
if (vasid)
*vasid = pswid >> (31 - 7) & 0xFF;
if (winid)
*winid = pswid & 0xFFFF;
}
#endif /* _VAS_H */