linux/drivers/irqchip/irq-dw-apb-ictl.c
Jisheng Zhang 1655b0530d irqchip: dw-apb-ictl: Add PM support
This patch adds in support for S2R for dw-apb-ictl irqchip driver.

We can used relaxed variants in the resume hook because there's no DMA
at all here, the device type memory attribute can ensure the operations
order and relaxed version imply compiler barrier.

Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
Link: https://lkml.kernel.org/r/1415773374-4629-4-git-send-email-jszhang@marvell.com
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
2014-11-26 16:08:03 +00:00

171 lines
4.6 KiB
C

/*
* Synopsys DW APB ICTL irqchip driver.
*
* Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
*
* based on GPL'ed 2.6 kernel sources
* (c) Marvell International Ltd.
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*/
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/irqchip/chained_irq.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include "irqchip.h"
#define APB_INT_ENABLE_L 0x00
#define APB_INT_ENABLE_H 0x04
#define APB_INT_MASK_L 0x08
#define APB_INT_MASK_H 0x0c
#define APB_INT_FINALSTATUS_L 0x30
#define APB_INT_FINALSTATUS_H 0x34
static void dw_apb_ictl_handler(unsigned int irq, struct irq_desc *desc)
{
struct irq_chip *chip = irq_get_chip(irq);
struct irq_chip_generic *gc = irq_get_handler_data(irq);
struct irq_domain *d = gc->private;
u32 stat;
int n;
chained_irq_enter(chip, desc);
for (n = 0; n < gc->num_ct; n++) {
stat = readl_relaxed(gc->reg_base +
APB_INT_FINALSTATUS_L + 4 * n);
while (stat) {
u32 hwirq = ffs(stat) - 1;
generic_handle_irq(irq_find_mapping(d,
gc->irq_base + hwirq + 32 * n));
stat &= ~(1 << hwirq);
}
}
chained_irq_exit(chip, desc);
}
#ifdef CONFIG_PM
static void dw_apb_ictl_resume(struct irq_data *d)
{
struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
struct irq_chip_type *ct = irq_data_get_chip_type(d);
irq_gc_lock(gc);
writel_relaxed(~0, gc->reg_base + ct->regs.enable);
writel_relaxed(*ct->mask_cache, gc->reg_base + ct->regs.mask);
irq_gc_unlock(gc);
}
#else
#define dw_apb_ictl_resume NULL
#endif /* CONFIG_PM */
static int __init dw_apb_ictl_init(struct device_node *np,
struct device_node *parent)
{
unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;
struct resource r;
struct irq_domain *domain;
struct irq_chip_generic *gc;
void __iomem *iobase;
int ret, nrirqs, irq;
u32 reg;
/* Map the parent interrupt for the chained handler */
irq = irq_of_parse_and_map(np, 0);
if (irq <= 0) {
pr_err("%s: unable to parse irq\n", np->full_name);
return -EINVAL;
}
ret = of_address_to_resource(np, 0, &r);
if (ret) {
pr_err("%s: unable to get resource\n", np->full_name);
return ret;
}
if (!request_mem_region(r.start, resource_size(&r), np->full_name)) {
pr_err("%s: unable to request mem region\n", np->full_name);
return -ENOMEM;
}
iobase = ioremap(r.start, resource_size(&r));
if (!iobase) {
pr_err("%s: unable to map resource\n", np->full_name);
ret = -ENOMEM;
goto err_release;
}
/*
* DW IP can be configured to allow 2-64 irqs. We can determine
* the number of irqs supported by writing into enable register
* and look for bits not set, as corresponding flip-flops will
* have been removed by sythesis tool.
*/
/* mask and enable all interrupts */
writel_relaxed(~0, iobase + APB_INT_MASK_L);
writel_relaxed(~0, iobase + APB_INT_MASK_H);
writel_relaxed(~0, iobase + APB_INT_ENABLE_L);
writel_relaxed(~0, iobase + APB_INT_ENABLE_H);
reg = readl_relaxed(iobase + APB_INT_ENABLE_H);
if (reg)
nrirqs = 32 + fls(reg);
else
nrirqs = fls(readl_relaxed(iobase + APB_INT_ENABLE_L));
domain = irq_domain_add_linear(np, nrirqs,
&irq_generic_chip_ops, NULL);
if (!domain) {
pr_err("%s: unable to add irq domain\n", np->full_name);
ret = -ENOMEM;
goto err_unmap;
}
ret = irq_alloc_domain_generic_chips(domain, 32, (nrirqs > 32) ? 2 : 1,
np->name, handle_level_irq, clr, 0,
IRQ_GC_MASK_CACHE_PER_TYPE |
IRQ_GC_INIT_MASK_CACHE);
if (ret) {
pr_err("%s: unable to alloc irq domain gc\n", np->full_name);
goto err_unmap;
}
gc = irq_get_domain_generic_chip(domain, 0);
gc->private = domain;
gc->reg_base = iobase;
gc->chip_types[0].regs.mask = APB_INT_MASK_L;
gc->chip_types[0].regs.enable = APB_INT_ENABLE_L;
gc->chip_types[0].chip.irq_mask = irq_gc_mask_set_bit;
gc->chip_types[0].chip.irq_unmask = irq_gc_mask_clr_bit;
gc->chip_types[0].chip.irq_resume = dw_apb_ictl_resume;
if (nrirqs > 32) {
gc->chip_types[1].regs.mask = APB_INT_MASK_H;
gc->chip_types[1].regs.enable = APB_INT_ENABLE_H;
gc->chip_types[1].chip.irq_mask = irq_gc_mask_set_bit;
gc->chip_types[1].chip.irq_unmask = irq_gc_mask_clr_bit;
gc->chip_types[1].chip.irq_resume = dw_apb_ictl_resume;
}
irq_set_handler_data(irq, gc);
irq_set_chained_handler(irq, dw_apb_ictl_handler);
return 0;
err_unmap:
iounmap(iobase);
err_release:
release_mem_region(r.start, resource_size(&r));
return ret;
}
IRQCHIP_DECLARE(dw_apb_ictl,
"snps,dw-apb-ictl", dw_apb_ictl_init);