linux_dsm_epyc7002/drivers/irqchip/irq-sirfsoc.c
Barry Song a87010ef32 irqchip: sirf: set IRQ_LEVEL status_flags
SiRF internal interrupts are using level trigger. we need to tell the irq
core this information. otherwise, we might get some problems as below
1. disable_irq(n)
here irq core will mark the disabled flag but still keep the irq enabled
due to involved lazy-disable
2. doing someting after disable_irq(n)
in step 2, if one interrupt n comes, irq core will mark it as pending and
mask the HW interrupt really. we name the coming interrupt as "X".
3. enable_irq(n)
this will unmask the interrupt, so the level-trigger HW interrupt will come
again, irq_handler will enter as "E1". after that, irq core will also check
whether irq n is pending, if yes, and pending interrupt is not level-trigger,
irq core will execute the pending irq_handler.
so if we don't set the IRQ_LEVEL flag here, irq core will execute pending
X again as "E2", but actually the pending interrupt has been handled by "E1".
that makes a level-trigger HW interrupt is executed twice.

here we fix the issue to avoid redundant interrupt overload.

Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Huayi Li <Huayi.Li@csr.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
2014-01-08 22:02:14 -08:00

130 lines
3.5 KiB
C

/*
* interrupt controller support for CSR SiRFprimaII
*
* Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company.
*
* Licensed under GPLv2 or later.
*/
#include <linux/init.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/irqdomain.h>
#include <linux/syscore_ops.h>
#include <asm/mach/irq.h>
#include <asm/exception.h>
#include "irqchip.h"
#define SIRFSOC_INT_RISC_MASK0 0x0018
#define SIRFSOC_INT_RISC_MASK1 0x001C
#define SIRFSOC_INT_RISC_LEVEL0 0x0020
#define SIRFSOC_INT_RISC_LEVEL1 0x0024
#define SIRFSOC_INIT_IRQ_ID 0x0038
#define SIRFSOC_NUM_IRQS 64
static struct irq_domain *sirfsoc_irqdomain;
static __init void
sirfsoc_alloc_gc(void __iomem *base, unsigned int irq_start, unsigned int num)
{
struct irq_chip_generic *gc;
struct irq_chip_type *ct;
int ret;
unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;
unsigned int set = IRQ_LEVEL;
ret = irq_alloc_domain_generic_chips(sirfsoc_irqdomain, num, 1, "irq_sirfsoc",
handle_level_irq, clr, set, IRQ_GC_INIT_MASK_CACHE);
gc = irq_get_domain_generic_chip(sirfsoc_irqdomain, irq_start);
gc->reg_base = base;
ct = gc->chip_types;
ct->chip.irq_mask = irq_gc_mask_clr_bit;
ct->chip.irq_unmask = irq_gc_mask_set_bit;
ct->regs.mask = SIRFSOC_INT_RISC_MASK0;
}
static asmlinkage void __exception_irq_entry sirfsoc_handle_irq(struct pt_regs *regs)
{
void __iomem *base = sirfsoc_irqdomain->host_data;
u32 irqstat, irqnr;
irqstat = readl_relaxed(base + SIRFSOC_INIT_IRQ_ID);
irqnr = irq_find_mapping(sirfsoc_irqdomain, irqstat & 0xff);
handle_IRQ(irqnr, regs);
}
static int __init sirfsoc_irq_init(struct device_node *np, struct device_node *parent)
{
void __iomem *base = of_iomap(np, 0);
if (!base)
panic("unable to map intc cpu registers\n");
sirfsoc_irqdomain = irq_domain_add_linear(np, SIRFSOC_NUM_IRQS,
&irq_generic_chip_ops, base);
sirfsoc_alloc_gc(base, 0, 32);
sirfsoc_alloc_gc(base + 4, 32, SIRFSOC_NUM_IRQS - 32);
writel_relaxed(0, base + SIRFSOC_INT_RISC_LEVEL0);
writel_relaxed(0, base + SIRFSOC_INT_RISC_LEVEL1);
writel_relaxed(0, base + SIRFSOC_INT_RISC_MASK0);
writel_relaxed(0, base + SIRFSOC_INT_RISC_MASK1);
set_handle_irq(sirfsoc_handle_irq);
return 0;
}
IRQCHIP_DECLARE(sirfsoc_intc, "sirf,prima2-intc", sirfsoc_irq_init);
struct sirfsoc_irq_status {
u32 mask0;
u32 mask1;
u32 level0;
u32 level1;
};
static struct sirfsoc_irq_status sirfsoc_irq_st;
static int sirfsoc_irq_suspend(void)
{
void __iomem *base = sirfsoc_irqdomain->host_data;
sirfsoc_irq_st.mask0 = readl_relaxed(base + SIRFSOC_INT_RISC_MASK0);
sirfsoc_irq_st.mask1 = readl_relaxed(base + SIRFSOC_INT_RISC_MASK1);
sirfsoc_irq_st.level0 = readl_relaxed(base + SIRFSOC_INT_RISC_LEVEL0);
sirfsoc_irq_st.level1 = readl_relaxed(base + SIRFSOC_INT_RISC_LEVEL1);
return 0;
}
static void sirfsoc_irq_resume(void)
{
void __iomem *base = sirfsoc_irqdomain->host_data;
writel_relaxed(sirfsoc_irq_st.mask0, base + SIRFSOC_INT_RISC_MASK0);
writel_relaxed(sirfsoc_irq_st.mask1, base + SIRFSOC_INT_RISC_MASK1);
writel_relaxed(sirfsoc_irq_st.level0, base + SIRFSOC_INT_RISC_LEVEL0);
writel_relaxed(sirfsoc_irq_st.level1, base + SIRFSOC_INT_RISC_LEVEL1);
}
static struct syscore_ops sirfsoc_irq_syscore_ops = {
.suspend = sirfsoc_irq_suspend,
.resume = sirfsoc_irq_resume,
};
static int __init sirfsoc_irq_pm_init(void)
{
if (!sirfsoc_irqdomain)
return 0;
register_syscore_ops(&sirfsoc_irq_syscore_ops);
return 0;
}
device_initcall(sirfsoc_irq_pm_init);