ARM: vic: MULTI_IRQ_HANDLER handler

Add a handler for the VIC that is suitable for MULTI_IRQ_HANDLER
platforms.  This can replace the ASM entry macros for platforms that use
the VIC.

v4:	- rebase ontop of move __exception and friends to
	  asm/exception.h
	- rework polling loop to handle as many irqs as possible in one go
v3:	- simplify irq handling loop as suggested by Grant
	- service interrupts from msb->lsb order
v2:	- allow the handler be used for !CONFIG_OF
	- use irq_domain_to_irq()

Cc: Rob Herring <robherring2@gmail.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Thomas Abraham <thomas.abraham@linaro.org>
Signed-off-by: Jamie Iles <jamie@jamieiles.com>
This commit is contained in:
Jamie Iles 2011-09-28 09:40:11 +01:00 committed by Marc Zyngier
parent f9b28ccbc7
commit 1558368eb5
2 changed files with 41 additions and 0 deletions

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@ -31,6 +31,7 @@
#include <linux/device.h>
#include <linux/amba/bus.h>
#include <asm/exception.h>
#include <asm/mach/irq.h>
#include <asm/hardware/vic.h>
@ -428,3 +429,40 @@ int __init vic_of_init(struct device_node *node, struct device_node *parent)
return -EIO;
}
#endif /* CONFIG OF */
#ifdef CONFIG_MULTI_IRQ_HANDLER
/*
* Handle each interrupt in a single VIC. Returns non-zero if we've
* handled at least one interrupt. This does a single read of the
* status register and handles all interrupts in order from LSB first.
*/
static int handle_one_vic(struct vic_device *vic, struct pt_regs *regs)
{
u32 stat, irq;
int handled = 0;
stat = readl_relaxed(vic->base + VIC_IRQ_STATUS);
while (stat) {
irq = ffs(stat) - 1;
handle_IRQ(irq_domain_to_irq(&vic->domain, irq), regs);
stat &= ~(1 << irq);
handled = 1;
}
return handled;
}
/*
* Keep iterating over all registered VIC's until there are no pending
* interrupts.
*/
asmlinkage void __exception_irq_entry vic_handle_irq(struct pt_regs *regs)
{
int i, handled;
do {
for (i = 0, handled = 0; i < vic_id; ++i)
handled |= handle_one_vic(&vic_devices[i], regs);
} while (handled);
}
#endif /* CONFIG_MULTI_IRQ_HANDLER */

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@ -45,8 +45,11 @@
#include <linux/types.h>
struct device_node;
struct pt_regs;
void vic_init(void __iomem *base, unsigned int irq_start, u32 vic_sources, u32 resume_sources);
int vic_of_init(struct device_node *node, struct device_node *parent);
void vic_handle_irq(struct pt_regs *regs);
#endif /* __ASSEMBLY__ */
#endif