linux/drivers/irqchip/irq-imx-irqsteer.c
Lucas Stach 4730d22333 irqchip/imx-irqsteer: Add runtime PM support
There are now SoCs that integrate the irqsteer controller within
a separate power domain. In order to allow this domain to be
powered down when not needed, add runtime PM support to the driver.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220406163701.1277930-2-l.stach@pengutronix.de
2022-05-04 16:44:51 +01:00

317 lines
7.7 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright 2017 NXP
* Copyright (C) 2018 Pengutronix, Lucas Stach <kernel@pengutronix.de>
*/
#include <linux/clk.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/irqchip/chained_irq.h>
#include <linux/irqdomain.h>
#include <linux/kernel.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
#include <linux/pm_runtime.h>
#include <linux/spinlock.h>
#define CTRL_STRIDE_OFF(_t, _r) (_t * 4 * _r)
#define CHANCTRL 0x0
#define CHANMASK(n, t) (CTRL_STRIDE_OFF(t, 0) + 0x4 * (n) + 0x4)
#define CHANSET(n, t) (CTRL_STRIDE_OFF(t, 1) + 0x4 * (n) + 0x4)
#define CHANSTATUS(n, t) (CTRL_STRIDE_OFF(t, 2) + 0x4 * (n) + 0x4)
#define CHAN_MINTDIS(t) (CTRL_STRIDE_OFF(t, 3) + 0x4)
#define CHAN_MASTRSTAT(t) (CTRL_STRIDE_OFF(t, 3) + 0x8)
#define CHAN_MAX_OUTPUT_INT 0x8
struct irqsteer_data {
void __iomem *regs;
struct clk *ipg_clk;
int irq[CHAN_MAX_OUTPUT_INT];
int irq_count;
raw_spinlock_t lock;
int reg_num;
int channel;
struct irq_domain *domain;
u32 *saved_reg;
};
static int imx_irqsteer_get_reg_index(struct irqsteer_data *data,
unsigned long irqnum)
{
return (data->reg_num - irqnum / 32 - 1);
}
static void imx_irqsteer_irq_unmask(struct irq_data *d)
{
struct irqsteer_data *data = d->chip_data;
int idx = imx_irqsteer_get_reg_index(data, d->hwirq);
unsigned long flags;
u32 val;
raw_spin_lock_irqsave(&data->lock, flags);
val = readl_relaxed(data->regs + CHANMASK(idx, data->reg_num));
val |= BIT(d->hwirq % 32);
writel_relaxed(val, data->regs + CHANMASK(idx, data->reg_num));
raw_spin_unlock_irqrestore(&data->lock, flags);
}
static void imx_irqsteer_irq_mask(struct irq_data *d)
{
struct irqsteer_data *data = d->chip_data;
int idx = imx_irqsteer_get_reg_index(data, d->hwirq);
unsigned long flags;
u32 val;
raw_spin_lock_irqsave(&data->lock, flags);
val = readl_relaxed(data->regs + CHANMASK(idx, data->reg_num));
val &= ~BIT(d->hwirq % 32);
writel_relaxed(val, data->regs + CHANMASK(idx, data->reg_num));
raw_spin_unlock_irqrestore(&data->lock, flags);
}
static const struct irq_chip imx_irqsteer_irq_chip = {
.name = "irqsteer",
.irq_mask = imx_irqsteer_irq_mask,
.irq_unmask = imx_irqsteer_irq_unmask,
};
static int imx_irqsteer_irq_map(struct irq_domain *h, unsigned int irq,
irq_hw_number_t hwirq)
{
irq_set_status_flags(irq, IRQ_LEVEL);
irq_set_chip_data(irq, h->host_data);
irq_set_chip_and_handler(irq, &imx_irqsteer_irq_chip, handle_level_irq);
return 0;
}
static const struct irq_domain_ops imx_irqsteer_domain_ops = {
.map = imx_irqsteer_irq_map,
.xlate = irq_domain_xlate_onecell,
};
static int imx_irqsteer_get_hwirq_base(struct irqsteer_data *data, u32 irq)
{
int i;
for (i = 0; i < data->irq_count; i++) {
if (data->irq[i] == irq)
return i * 64;
}
return -EINVAL;
}
static void imx_irqsteer_irq_handler(struct irq_desc *desc)
{
struct irqsteer_data *data = irq_desc_get_handler_data(desc);
int hwirq;
int irq, i;
chained_irq_enter(irq_desc_get_chip(desc), desc);
irq = irq_desc_get_irq(desc);
hwirq = imx_irqsteer_get_hwirq_base(data, irq);
if (hwirq < 0) {
pr_warn("%s: unable to get hwirq base for irq %d\n",
__func__, irq);
return;
}
for (i = 0; i < 2; i++, hwirq += 32) {
int idx = imx_irqsteer_get_reg_index(data, hwirq);
unsigned long irqmap;
int pos;
if (hwirq >= data->reg_num * 32)
break;
irqmap = readl_relaxed(data->regs +
CHANSTATUS(idx, data->reg_num));
for_each_set_bit(pos, &irqmap, 32)
generic_handle_domain_irq(data->domain, pos + hwirq);
}
chained_irq_exit(irq_desc_get_chip(desc), desc);
}
static int imx_irqsteer_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
struct irqsteer_data *data;
u32 irqs_num;
int i, ret;
data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
data->regs = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(data->regs)) {
dev_err(&pdev->dev, "failed to initialize reg\n");
return PTR_ERR(data->regs);
}
data->ipg_clk = devm_clk_get(&pdev->dev, "ipg");
if (IS_ERR(data->ipg_clk))
return dev_err_probe(&pdev->dev, PTR_ERR(data->ipg_clk),
"failed to get ipg clk\n");
raw_spin_lock_init(&data->lock);
ret = of_property_read_u32(np, "fsl,num-irqs", &irqs_num);
if (ret)
return ret;
ret = of_property_read_u32(np, "fsl,channel", &data->channel);
if (ret)
return ret;
/*
* There is one output irq for each group of 64 inputs.
* One register bit map can represent 32 input interrupts.
*/
data->irq_count = DIV_ROUND_UP(irqs_num, 64);
data->reg_num = irqs_num / 32;
if (IS_ENABLED(CONFIG_PM)) {
data->saved_reg = devm_kzalloc(&pdev->dev,
sizeof(u32) * data->reg_num,
GFP_KERNEL);
if (!data->saved_reg)
return -ENOMEM;
}
ret = clk_prepare_enable(data->ipg_clk);
if (ret) {
dev_err(&pdev->dev, "failed to enable ipg clk: %d\n", ret);
return ret;
}
/* steer all IRQs into configured channel */
writel_relaxed(BIT(data->channel), data->regs + CHANCTRL);
data->domain = irq_domain_add_linear(np, data->reg_num * 32,
&imx_irqsteer_domain_ops, data);
if (!data->domain) {
dev_err(&pdev->dev, "failed to create IRQ domain\n");
ret = -ENOMEM;
goto out;
}
irq_domain_set_pm_device(data->domain, &pdev->dev);
if (!data->irq_count || data->irq_count > CHAN_MAX_OUTPUT_INT) {
ret = -EINVAL;
goto out;
}
for (i = 0; i < data->irq_count; i++) {
data->irq[i] = irq_of_parse_and_map(np, i);
if (!data->irq[i]) {
ret = -EINVAL;
goto out;
}
irq_set_chained_handler_and_data(data->irq[i],
imx_irqsteer_irq_handler,
data);
}
platform_set_drvdata(pdev, data);
pm_runtime_set_active(&pdev->dev);
pm_runtime_enable(&pdev->dev);
return 0;
out:
clk_disable_unprepare(data->ipg_clk);
return ret;
}
static int imx_irqsteer_remove(struct platform_device *pdev)
{
struct irqsteer_data *irqsteer_data = platform_get_drvdata(pdev);
int i;
for (i = 0; i < irqsteer_data->irq_count; i++)
irq_set_chained_handler_and_data(irqsteer_data->irq[i],
NULL, NULL);
irq_domain_remove(irqsteer_data->domain);
clk_disable_unprepare(irqsteer_data->ipg_clk);
return 0;
}
#ifdef CONFIG_PM
static void imx_irqsteer_save_regs(struct irqsteer_data *data)
{
int i;
for (i = 0; i < data->reg_num; i++)
data->saved_reg[i] = readl_relaxed(data->regs +
CHANMASK(i, data->reg_num));
}
static void imx_irqsteer_restore_regs(struct irqsteer_data *data)
{
int i;
writel_relaxed(BIT(data->channel), data->regs + CHANCTRL);
for (i = 0; i < data->reg_num; i++)
writel_relaxed(data->saved_reg[i],
data->regs + CHANMASK(i, data->reg_num));
}
static int imx_irqsteer_suspend(struct device *dev)
{
struct irqsteer_data *irqsteer_data = dev_get_drvdata(dev);
imx_irqsteer_save_regs(irqsteer_data);
clk_disable_unprepare(irqsteer_data->ipg_clk);
return 0;
}
static int imx_irqsteer_resume(struct device *dev)
{
struct irqsteer_data *irqsteer_data = dev_get_drvdata(dev);
int ret;
ret = clk_prepare_enable(irqsteer_data->ipg_clk);
if (ret) {
dev_err(dev, "failed to enable ipg clk: %d\n", ret);
return ret;
}
imx_irqsteer_restore_regs(irqsteer_data);
return 0;
}
#endif
static const struct dev_pm_ops imx_irqsteer_pm_ops = {
SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
pm_runtime_force_resume)
SET_RUNTIME_PM_OPS(imx_irqsteer_suspend,
imx_irqsteer_resume, NULL)
};
static const struct of_device_id imx_irqsteer_dt_ids[] = {
{ .compatible = "fsl,imx-irqsteer", },
{},
};
static struct platform_driver imx_irqsteer_driver = {
.driver = {
.name = "imx-irqsteer",
.of_match_table = imx_irqsteer_dt_ids,
.pm = &imx_irqsteer_pm_ops,
},
.probe = imx_irqsteer_probe,
.remove = imx_irqsteer_remove,
};
builtin_platform_driver(imx_irqsteer_driver);