blob: f790ca6d78aa4c534723a145931e6ece45933523 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2020, Jiaxun Yang <jiaxun.yang@flygoat.com>
* Loongson PCH PIC support
*/
#define pr_fmt(fmt) "pch-pic: " fmt
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/irqchip.h>
#include <linux/irqdomain.h>
#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
/* Registers */
#define PCH_PIC_MASK 0x20
#define PCH_PIC_HTMSI_EN 0x40
#define PCH_PIC_EDGE 0x60
#define PCH_PIC_CLR 0x80
#define PCH_PIC_AUTO0 0xc0
#define PCH_PIC_AUTO1 0xe0
#define PCH_INT_ROUTE(irq) (0x100 + irq)
#define PCH_INT_HTVEC(irq) (0x200 + irq)
#define PCH_PIC_POL 0x3e0
#define PIC_COUNT_PER_REG 32
#define PIC_REG_COUNT 2
#define PIC_COUNT (PIC_COUNT_PER_REG * PIC_REG_COUNT)
#define PIC_REG_IDX(irq_id) ((irq_id) / PIC_COUNT_PER_REG)
#define PIC_REG_BIT(irq_id) ((irq_id) % PIC_COUNT_PER_REG)
struct pch_pic {
void __iomem *base;
struct irq_domain *pic_domain;
u32 ht_vec_base;
raw_spinlock_t pic_lock;
};
static void pch_pic_bitset(struct pch_pic *priv, int offset, int bit)
{
u32 reg;
void __iomem *addr = priv->base + offset + PIC_REG_IDX(bit) * 4;
raw_spin_lock(&priv->pic_lock);
reg = readl(addr);
reg |= BIT(PIC_REG_BIT(bit));
writel(reg, addr);
raw_spin_unlock(&priv->pic_lock);
}
static void pch_pic_bitclr(struct pch_pic *priv, int offset, int bit)
{
u32 reg;
void __iomem *addr = priv->base + offset + PIC_REG_IDX(bit) * 4;
raw_spin_lock(&priv->pic_lock);
reg = readl(addr);
reg &= ~BIT(PIC_REG_BIT(bit));
writel(reg, addr);
raw_spin_unlock(&priv->pic_lock);
}
static void pch_pic_mask_irq(struct irq_data *d)
{
struct pch_pic *priv = irq_data_get_irq_chip_data(d);
pch_pic_bitset(priv, PCH_PIC_MASK, d->hwirq);
irq_chip_mask_parent(d);
}
static void pch_pic_unmask_irq(struct irq_data *d)
{
struct pch_pic *priv = irq_data_get_irq_chip_data(d);
writel(BIT(PIC_REG_BIT(d->hwirq)),
priv->base + PCH_PIC_CLR + PIC_REG_IDX(d->hwirq) * 4);
irq_chip_unmask_parent(d);
pch_pic_bitclr(priv, PCH_PIC_MASK, d->hwirq);
}
static int pch_pic_set_type(struct irq_data *d, unsigned int type)
{
struct pch_pic *priv = irq_data_get_irq_chip_data(d);
int ret = 0;
switch (type) {
case IRQ_TYPE_EDGE_RISING:
pch_pic_bitset(priv, PCH_PIC_EDGE, d->hwirq);
pch_pic_bitclr(priv, PCH_PIC_POL, d->hwirq);
break;
case IRQ_TYPE_EDGE_FALLING:
pch_pic_bitset(priv, PCH_PIC_EDGE, d->hwirq);
pch_pic_bitset(priv, PCH_PIC_POL, d->hwirq);
break;
case IRQ_TYPE_LEVEL_HIGH:
pch_pic_bitclr(priv, PCH_PIC_EDGE, d->hwirq);
pch_pic_bitclr(priv, PCH_PIC_POL, d->hwirq);
break;
case IRQ_TYPE_LEVEL_LOW:
pch_pic_bitclr(priv, PCH_PIC_EDGE, d->hwirq);
pch_pic_bitset(priv, PCH_PIC_POL, d->hwirq);
break;
default:
ret = -EINVAL;
break;
}
return ret;
}
static struct irq_chip pch_pic_irq_chip = {
.name = "PCH PIC",
.irq_mask = pch_pic_mask_irq,
.irq_unmask = pch_pic_unmask_irq,
.irq_ack = irq_chip_ack_parent,
.irq_set_affinity = irq_chip_set_affinity_parent,
.irq_set_type = pch_pic_set_type,
};
static int pch_pic_alloc(struct irq_domain *domain, unsigned int virq,
unsigned int nr_irqs, void *arg)
{
int err;
unsigned int type;
unsigned long hwirq;
struct irq_fwspec *fwspec = arg;
struct irq_fwspec parent_fwspec;
struct pch_pic *priv = domain->host_data;
err = irq_domain_translate_twocell(domain, fwspec, &hwirq, &type);
if (err)
return err;
parent_fwspec.fwnode = domain->parent->fwnode;
parent_fwspec.param_count = 1;
parent_fwspec.param[0] = hwirq + priv->ht_vec_base;
err = irq_domain_alloc_irqs_parent(domain, virq, 1, &parent_fwspec);
if (err)
return err;
irq_domain_set_info(domain, virq, hwirq,
&pch_pic_irq_chip, priv,
handle_level_irq, NULL, NULL);
irq_set_probe(virq);
return 0;
}
static const struct irq_domain_ops pch_pic_domain_ops = {
.translate = irq_domain_translate_twocell,
.alloc = pch_pic_alloc,
.free = irq_domain_free_irqs_parent,
};
static void pch_pic_reset(struct pch_pic *priv)
{
int i;
for (i = 0; i < PIC_COUNT; i++) {
/* Write vectored ID */
writeb(priv->ht_vec_base + i, priv->base + PCH_INT_HTVEC(i));
/* Hardcode route to HT0 Lo */
writeb(1, priv->base + PCH_INT_ROUTE(i));
}
for (i = 0; i < PIC_REG_COUNT; i++) {
/* Clear IRQ cause registers, mask all interrupts */
writel_relaxed(0xFFFFFFFF, priv->base + PCH_PIC_MASK + 4 * i);
writel_relaxed(0xFFFFFFFF, priv->base + PCH_PIC_CLR + 4 * i);
/* Clear auto bounce, we don't need that */
writel_relaxed(0, priv->base + PCH_PIC_AUTO0 + 4 * i);
writel_relaxed(0, priv->base + PCH_PIC_AUTO1 + 4 * i);
/* Enable HTMSI transformer */
writel_relaxed(0xFFFFFFFF, priv->base + PCH_PIC_HTMSI_EN + 4 * i);
}
}
static int pch_pic_of_init(struct device_node *node,
struct device_node *parent)
{
struct pch_pic *priv;
struct irq_domain *parent_domain;
int err;
priv = kzalloc(sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
raw_spin_lock_init(&priv->pic_lock);
priv->base = of_iomap(node, 0);
if (!priv->base) {
err = -ENOMEM;
goto free_priv;
}
parent_domain = irq_find_host(parent);
if (!parent_domain) {
pr_err("Failed to find the parent domain\n");
err = -ENXIO;
goto iounmap_base;
}
if (of_property_read_u32(node, "loongson,pic-base-vec",
&priv->ht_vec_base)) {
pr_err("Failed to determine pic-base-vec\n");
err = -EINVAL;
goto iounmap_base;
}
priv->pic_domain = irq_domain_create_hierarchy(parent_domain, 0,
PIC_COUNT,
of_node_to_fwnode(node),
&pch_pic_domain_ops,
priv);
if (!priv->pic_domain) {
pr_err("Failed to create IRQ domain\n");
err = -ENOMEM;
goto iounmap_base;
}
pch_pic_reset(priv);
return 0;
iounmap_base:
iounmap(priv->base);
free_priv:
kfree(priv);
return err;
}
IRQCHIP_DECLARE(pch_pic, "loongson,pch-pic-1.0", pch_pic_of_init);