irq-imgpdc.c
/*
* IMG PowerDown Controller (PDC)
*
* Copyright 2010-2013 Imagination Technologies Ltd.
*
* Exposes the syswake and PDC peripheral wake interrupts to the system.
*
*/
#include <linux/bitops.h>
#include <linux/interrupt.h>
#include <linux/irqdomain.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/spinlock.h>
/* PDC interrupt register numbers */
#define PDC_IRQ_STATUS 0x310
#define PDC_IRQ_ENABLE 0x314
#define PDC_IRQ_CLEAR 0x318
#define PDC_IRQ_ROUTE 0x31c
#define PDC_SYS_WAKE_BASE 0x330
#define PDC_SYS_WAKE_STRIDE 0x8
#define PDC_SYS_WAKE_CONFIG_BASE 0x334
#define PDC_SYS_WAKE_CONFIG_STRIDE 0x8
/* PDC interrupt register field masks */
#define PDC_IRQ_SYS3 0x08
#define PDC_IRQ_SYS2 0x04
#define PDC_IRQ_SYS1 0x02
#define PDC_IRQ_SYS0 0x01
#define PDC_IRQ_ROUTE_WU_EN_SYS3 0x08000000
#define PDC_IRQ_ROUTE_WU_EN_SYS2 0x04000000
#define PDC_IRQ_ROUTE_WU_EN_SYS1 0x02000000
#define PDC_IRQ_ROUTE_WU_EN_SYS0 0x01000000
#define PDC_IRQ_ROUTE_WU_EN_WD 0x00040000
#define PDC_IRQ_ROUTE_WU_EN_IR 0x00020000
#define PDC_IRQ_ROUTE_WU_EN_RTC 0x00010000
#define PDC_IRQ_ROUTE_EXT_EN_SYS3 0x00000800
#define PDC_IRQ_ROUTE_EXT_EN_SYS2 0x00000400
#define PDC_IRQ_ROUTE_EXT_EN_SYS1 0x00000200
#define PDC_IRQ_ROUTE_EXT_EN_SYS0 0x00000100
#define PDC_IRQ_ROUTE_EXT_EN_WD 0x00000004
#define PDC_IRQ_ROUTE_EXT_EN_IR 0x00000002
#define PDC_IRQ_ROUTE_EXT_EN_RTC 0x00000001
#define PDC_SYS_WAKE_RESET 0x00000010
#define PDC_SYS_WAKE_INT_MODE 0x0000000e
#define PDC_SYS_WAKE_INT_MODE_SHIFT 1
#define PDC_SYS_WAKE_PIN_VAL 0x00000001
/* PDC interrupt constants */
#define PDC_SYS_WAKE_INT_LOW 0x0
#define PDC_SYS_WAKE_INT_HIGH 0x1
#define PDC_SYS_WAKE_INT_DOWN 0x2
#define PDC_SYS_WAKE_INT_UP 0x3
#define PDC_SYS_WAKE_INT_CHANGE 0x6
#define PDC_SYS_WAKE_INT_NONE 0x4
/**
* struct pdc_intc_priv - private pdc interrupt data.
* @nr_perips: Number of peripheral interrupt signals.
* @nr_syswakes: Number of syswake signals.
* @perip_irqs: List of peripheral IRQ numbers handled.
* @syswake_irq: Shared PDC syswake IRQ number.
* @domain: IRQ domain for PDC peripheral and syswake IRQs.
* @pdc_base: Base of PDC registers.
* @irq_route: Cached version of PDC_IRQ_ROUTE register.
* @lock: Lock to protect the PDC syswake registers and the cached
* values of those registers in this struct.
*/
struct pdc_intc_priv {
unsigned int nr_perips;
unsigned int nr_syswakes;
unsigned int *perip_irqs;
unsigned int syswake_irq;
struct irq_domain *domain;
void __iomem *pdc_base;
u32 irq_route;
raw_spinlock_t lock;
};
static void pdc_write(struct pdc_intc_priv *priv, unsigned int reg_offs,
unsigned int data)
{
iowrite32(data, priv->pdc_base + reg_offs);
}
static unsigned int pdc_read(struct pdc_intc_priv *priv,
unsigned int reg_offs)
{
return ioread32(priv->pdc_base + reg_offs);
}
/* Generic IRQ callbacks */
#define SYS0_HWIRQ 8
static unsigned int hwirq_is_syswake(irq_hw_number_t hw)
{
return hw >= SYS0_HWIRQ;
}
static unsigned int hwirq_to_syswake(irq_hw_number_t hw)
{
return hw - SYS0_HWIRQ;
}
static irq_hw_number_t syswake_to_hwirq(unsigned int syswake)
{
return SYS0_HWIRQ + syswake;
}
static struct pdc_intc_priv *irqd_to_priv(struct irq_data *data)
{
return (struct pdc_intc_priv *)data->domain->host_data;
}
/*
* perip_irq_mask() and perip_irq_unmask() use IRQ_ROUTE which also contains
* wake bits, therefore we cannot use the generic irqchip mask callbacks as they
* cache the mask.
*/
static void perip_irq_mask(struct irq_data *data)
{
struct pdc_intc_priv *priv = irqd_to_priv(data);
raw_spin_lock(&priv->lock);
priv->irq_route &= ~data->mask;
pdc_write(priv, PDC_IRQ_ROUTE, priv->irq_route);
raw_spin_unlock(&priv->lock);
}
static void perip_irq_unmask(struct irq_data *data)
{
struct pdc_intc_priv *priv = irqd_to_priv(data);
raw_spin_lock(&priv->lock);
priv->irq_route |= data->mask;
pdc_write(priv, PDC_IRQ_ROUTE, priv->irq_route);
raw_spin_unlock(&priv->lock);
}
static int syswake_irq_set_type(struct irq_data *data, unsigned int flow_type)
{
struct pdc_intc_priv *priv = irqd_to_priv(data);
unsigned int syswake = hwirq_to_syswake(data->hwirq);
unsigned int irq_mode;
unsigned int soc_sys_wake_regoff, soc_sys_wake;
/* translate to syswake IRQ mode */
switch (flow_type) {
case IRQ_TYPE_EDGE_BOTH:
irq_mode = PDC_SYS_WAKE_INT_CHANGE;
break;
case IRQ_TYPE_EDGE_RISING:
irq_mode = PDC_SYS_WAKE_INT_UP;
break;
case IRQ_TYPE_EDGE_FALLING:
irq_mode = PDC_SYS_WAKE_INT_DOWN;
break;
case IRQ_TYPE_LEVEL_HIGH:
irq_mode = PDC_SYS_WAKE_INT_HIGH;
break;
case IRQ_TYPE_LEVEL_LOW:
irq_mode = PDC_SYS_WAKE_INT_LOW;
break;
default:
return -EINVAL;
}
raw_spin_lock(&priv->lock);
/* set the IRQ mode */
soc_sys_wake_regoff = PDC_SYS_WAKE_BASE + syswake*PDC_SYS_WAKE_STRIDE;
soc_sys_wake = pdc_read(priv, soc_sys_wake_regoff);
soc_sys_wake &= ~PDC_SYS_WAKE_INT_MODE;
soc_sys_wake |= irq_mode << PDC_SYS_WAKE_INT_MODE_SHIFT;
pdc_write(priv, soc_sys_wake_regoff, soc_sys_wake);
/* and update the handler */
irq_setup_alt_chip(data, flow_type);
raw_spin_unlock(&priv->lock);
return 0;
}
/* applies to both peripheral and syswake interrupts */
static int pdc_irq_set_wake(struct irq_data *data, unsigned int on)
{
struct pdc_intc_priv *priv = irqd_to_priv(data);
irq_hw_number_t hw = data->hwirq;
unsigned int mask = (1 << 16) << hw;
unsigned int dst_irq;
raw_spin_lock(&priv->lock);
if (on)
priv->irq_route |= mask;
else
priv->irq_route &= ~mask;
pdc_write(priv, PDC_IRQ_ROUTE, priv->irq_route);
raw_spin_unlock(&priv->lock);
/* control the destination IRQ wakeup too for standby mode */
if (hwirq_is_syswake(hw))
dst_irq = priv->syswake_irq;
else
dst_irq = priv->perip_irqs[hw];
irq_set_irq_wake(dst_irq, on);
return 0;
}
static void pdc_intc_perip_isr(unsigned int irq, struct irq_desc *desc)
{
struct pdc_intc_priv *priv;
unsigned int i, irq_no;
priv = (struct pdc_intc_priv *)irq_desc_get_handler_data(desc);
/* find the peripheral number */
for (i = 0; i < priv->nr_perips; ++i)
if (irq == priv->perip_irqs[i])
goto found;
/* should never get here */
return;
found:
/* pass on the interrupt */
irq_no = irq_linear_revmap(priv->domain, i);
generic_handle_irq(irq_no);
}
static void pdc_intc_syswake_isr(unsigned int irq, struct irq_desc *desc)
{
struct pdc_intc_priv *priv;
unsigned int syswake, irq_no;
unsigned int status;
priv = (struct pdc_intc_priv *)irq_desc_get_handler_data(desc);
status = pdc_read(priv, PDC_IRQ_STATUS) &
pdc_read(priv, PDC_IRQ_ENABLE);
status &= (1 << priv->nr_syswakes) - 1;
for (syswake = 0; status; status >>= 1, ++syswake) {
/* Has this sys_wake triggered? */
if (!(status & 1))
continue;
irq_no = irq_linear_revmap(priv->domain,
syswake_to_hwirq(syswake));
generic_handle_irq(irq_no);
}
}
static void pdc_intc_setup(struct pdc_intc_priv *priv)
{
int i;
unsigned int soc_sys_wake_regoff;
unsigned int soc_sys_wake;
/*
* Mask all syswake interrupts before routing, or we could receive an
* interrupt before we're ready to handle it.
*/
pdc_write(priv, PDC_IRQ_ENABLE, 0);
/*
* Enable routing of all syswakes
* Disable all wake sources
*/
priv->irq_route = ((PDC_IRQ_ROUTE_EXT_EN_SYS0 << priv->nr_syswakes) -
PDC_IRQ_ROUTE_EXT_EN_SYS0);
pdc_write(priv, PDC_IRQ_ROUTE, priv->irq_route);
/* Initialise syswake IRQ */
for (i = 0; i < priv->nr_syswakes; ++i) {
/* set the IRQ mode to none */
soc_sys_wake_regoff = PDC_SYS_WAKE_BASE + i*PDC_SYS_WAKE_STRIDE;
soc_sys_wake = PDC_SYS_WAKE_INT_NONE
<< PDC_SYS_WAKE_INT_MODE_SHIFT;
pdc_write(priv, soc_sys_wake_regoff, soc_sys_wake);
}
}
static int pdc_intc_probe(struct platform_device *pdev)
{
struct pdc_intc_priv *priv;
struct device_node *node = pdev->dev.of_node;
struct resource *res_regs;
struct irq_chip_generic *gc;
unsigned int i;
int irq, ret;
u32 val;
if (!node)
return -ENOENT;
/* Get registers */
res_regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (res_regs == NULL) {
dev_err(&pdev->dev, "cannot find registers resource\n");
return -ENOENT;
}
/* Allocate driver data */
priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
if (!priv) {
dev_err(&pdev->dev, "cannot allocate device data\n");
return -ENOMEM;
}
raw_spin_lock_init(&priv->lock);
platform_set_drvdata(pdev, priv);
/* Ioremap the registers */
priv->pdc_base = devm_ioremap(&pdev->dev, res_regs->start,
res_regs->end - res_regs->start);
if (!priv->pdc_base)
return -EIO;
/* Get number of peripherals */
ret = of_property_read_u32(node, "num-perips", &val);
if (ret) {
dev_err(&pdev->dev, "No num-perips node property found\n");
return -EINVAL;
}
if (val > SYS0_HWIRQ) {
dev_err(&pdev->dev, "num-perips (%u) out of range\n", val);
return -EINVAL;
}
priv->nr_perips = val;
/* Get number of syswakes */
ret = of_property_read_u32(node, "num-syswakes", &val);
if (ret) {
dev_err(&pdev->dev, "No num-syswakes node property found\n");
return -EINVAL;
}
if (val > SYS0_HWIRQ) {
dev_err(&pdev->dev, "num-syswakes (%u) out of range\n", val);
return -EINVAL;
}
priv->nr_syswakes = val;
/* Get peripheral IRQ numbers */
priv->perip_irqs = devm_kzalloc(&pdev->dev, 4 * priv->nr_perips,
GFP_KERNEL);
if (!priv->perip_irqs) {
dev_err(&pdev->dev, "cannot allocate perip IRQ list\n");
return -ENOMEM;
}
for (i = 0; i < priv->nr_perips; ++i) {
irq = platform_get_irq(pdev, 1 + i);
if (irq < 0) {
dev_err(&pdev->dev, "cannot find perip IRQ #%u\n", i);
return irq;
}
priv->perip_irqs[i] = irq;
}
/* check if too many were provided */
if (platform_get_irq(pdev, 1 + i) >= 0) {
dev_err(&pdev->dev, "surplus perip IRQs detected\n");
return -EINVAL;
}
/* Get syswake IRQ number */
irq = platform_get_irq(pdev, 0);
if (irq < 0) {
dev_err(&pdev->dev, "cannot find syswake IRQ\n");
return irq;
}
priv->syswake_irq = irq;
/* Set up an IRQ domain */
priv->domain = irq_domain_add_linear(node, 16, &irq_generic_chip_ops,
priv);
if (unlikely(!priv->domain)) {
dev_err(&pdev->dev, "cannot add IRQ domain\n");
return -ENOMEM;
}
/*
* Set up 2 generic irq chips with 2 chip types.
* The first one for peripheral irqs (only 1 chip type used)
* The second one for syswake irqs (edge and level chip types)
*/
ret = irq_alloc_domain_generic_chips(priv->domain, 8, 2, "pdc",
handle_level_irq, 0, 0,
IRQ_GC_INIT_NESTED_LOCK);
if (ret)
goto err_generic;
/* peripheral interrupt chip */
gc = irq_get_domain_generic_chip(priv->domain, 0);
gc->unused = ~(BIT(priv->nr_perips) - 1);
gc->reg_base = priv->pdc_base;
/*
* IRQ_ROUTE contains wake bits, so we can't use the generic versions as
* they cache the mask
*/
gc->chip_types[0].regs.mask = PDC_IRQ_ROUTE;
gc->chip_types[0].chip.irq_mask = perip_irq_mask;
gc->chip_types[0].chip.irq_unmask = perip_irq_unmask;
gc->chip_types[0].chip.irq_set_wake = pdc_irq_set_wake;
/* syswake interrupt chip */
gc = irq_get_domain_generic_chip(priv->domain, 8);
gc->unused = ~(BIT(priv->nr_syswakes) - 1);
gc->reg_base = priv->pdc_base;
/* edge interrupts */
gc->chip_types[0].type = IRQ_TYPE_EDGE_BOTH;
gc->chip_types[0].handler = handle_edge_irq;
gc->chip_types[0].regs.ack = PDC_IRQ_CLEAR;
gc->chip_types[0].regs.mask = PDC_IRQ_ENABLE;
gc->chip_types[0].chip.irq_ack = irq_gc_ack_set_bit;
gc->chip_types[0].chip.irq_mask = irq_gc_mask_clr_bit;
gc->chip_types[0].chip.irq_unmask = irq_gc_mask_set_bit;
gc->chip_types[0].chip.irq_set_type = syswake_irq_set_type;
gc->chip_types[0].chip.irq_set_wake = pdc_irq_set_wake;
/* for standby we pass on to the shared syswake IRQ */
gc->chip_types[0].chip.flags = IRQCHIP_MASK_ON_SUSPEND;
/* level interrupts */
gc->chip_types[1].type = IRQ_TYPE_LEVEL_MASK;
gc->chip_types[1].handler = handle_level_irq;
gc->chip_types[1].regs.ack = PDC_IRQ_CLEAR;
gc->chip_types[1].regs.mask = PDC_IRQ_ENABLE;
gc->chip_types[1].chip.irq_ack = irq_gc_ack_set_bit;
gc->chip_types[1].chip.irq_mask = irq_gc_mask_clr_bit;
gc->chip_types[1].chip.irq_unmask = irq_gc_mask_set_bit;
gc->chip_types[1].chip.irq_set_type = syswake_irq_set_type;
gc->chip_types[1].chip.irq_set_wake = pdc_irq_set_wake;
/* for standby we pass on to the shared syswake IRQ */
gc->chip_types[1].chip.flags = IRQCHIP_MASK_ON_SUSPEND;
/* Set up the hardware to enable interrupt routing */
pdc_intc_setup(priv);
/* Setup chained handlers for the peripheral IRQs */
for (i = 0; i < priv->nr_perips; ++i) {
irq = priv->perip_irqs[i];
irq_set_handler_data(irq, priv);
irq_set_chained_handler(irq, pdc_intc_perip_isr);
}
/* Setup chained handler for the syswake IRQ */
irq_set_handler_data(priv->syswake_irq, priv);
irq_set_chained_handler(priv->syswake_irq, pdc_intc_syswake_isr);
dev_info(&pdev->dev,
"PDC IRQ controller initialised (%u perip IRQs, %u syswake IRQs)\n",
priv->nr_perips,
priv->nr_syswakes);
return 0;
err_generic:
irq_domain_remove(priv->domain);
return ret;
}
static int pdc_intc_remove(struct platform_device *pdev)
{
struct pdc_intc_priv *priv = platform_get_drvdata(pdev);
irq_domain_remove(priv->domain);
return 0;
}
static const struct of_device_id pdc_intc_match[] = {
{ .compatible = "img,pdc-intc" },
{}
};
static struct platform_driver pdc_intc_driver = {
.driver = {
.name = "pdc-intc",
.of_match_table = pdc_intc_match,
},
.probe = pdc_intc_probe,
.remove = pdc_intc_remove,
};
static int __init pdc_intc_init(void)
{
return platform_driver_register(&pdc_intc_driver);
}
core_initcall(pdc_intc_init);