ARC: Fix/unify cpu private IRQ requests (TIMER/IPI)

IPI IRQ request was broken as it was effectively being enabled on
boot-core only. The band aid was to make it like timer irq registration:
     cpu == 0 ? setup_irq() : arch_unmask_irq()

This is ugly (even in current timer code) as it requires need to expose
arch_unmask_irq() outside of intc code. So switch to percpu IRQ APIs:
  -request_percpu_irq [boot core]
  -enable_percpu_irq  [all cores]

Since TIMER and IPI both use this infrastructure, encapsulate this in a
helper arc_request_percpu_irq()

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

diff --git a/arch/arc/include/asm/irq.h b/arch/arc/include/asm/irq.h
index 781f57f25bd8d10ff0d85dfb6a18ca5d396117f9..6b7aaab534de04e0199a9384806c3643e6e51a0e 100644 (file)
--- a/arch/arc/include/asm/irq.h
+++ b/arch/arc/include/asm/irq.h
@@ -16,9 +16,13 @@
 #define TIMER0_IRQ      3
 #define TIMER1_IRQ      4
 
+#include <linux/interrupt.h>
 #include <asm-generic/irq.h>
 
 extern void arc_init_IRQ(void);
 void arc_local_timer_setup(unsigned int cpu);
+void arc_request_percpu_irq(int irq, int cpu,
+                            irqreturn_t (*hldr)(int irq, void *dev),
+                            const char *irq_nm, void *percpu_dev);
 
 #endif

diff --git a/arch/arc/kernel/irq.c b/arch/arc/kernel/irq.c
index 7d653c0d077390fa31bc70a6e6e67cbf78ad33a8..835fa5e71b628768993c48d9f2063ec6a4bab609 100644 (file)
--- a/arch/arc/kernel/irq.c
+++ b/arch/arc/kernel/irq.c
@@ -150,6 +150,32 @@ void arch_do_IRQ(unsigned int irq, struct pt_regs *regs)
        set_irq_regs(old_regs);
 }
 
+void arc_request_percpu_irq(int irq, int cpu,
+                            irqreturn_t (*isr)(int irq, void *dev),
+                            const char *irq_nm,
+                            void *percpu_dev)
+{
+       /* Boot cpu calls request, all call enable */
+       if (!cpu) {
+               int rc;
+
+               /*
+                * These 2 calls are essential to making percpu IRQ APIs work
+                * Ideally these details could be hidden in irq chip map function
+                * but the issue is IPIs IRQs being static (non-DT) and platform
+                * specific, so we can't identify them there.
+                */
+               irq_set_percpu_devid(irq);
+               irq_modify_status(irq, IRQ_NOAUTOEN, 0);  /* @irq, @clr, @set */
+
+               rc = request_percpu_irq(irq, isr, irq_nm, percpu_dev);
+               if (rc)
+                       panic("Percpu IRQ request failed for %d\n", irq);
+       }
+
+       enable_percpu_irq(irq, 0);
+}
+
 /*
  * arch_local_irq_enable - Enable interrupts.
  *

diff --git a/arch/arc/kernel/smp.c b/arch/arc/kernel/smp.c
index 40859e5619f914115ba010641094aa3a3ca5a8b3..2ef73a479975decc1ebb5cd044f3c51e0c39b109 100644 (file)
--- a/arch/arc/kernel/smp.c
+++ b/arch/arc/kernel/smp.c
@@ -337,8 +337,12 @@ irqreturn_t do_IPI(int irq, void *dev_id)
  * API called by platform code to hookup arch-common ISR to their IPI IRQ
  */
 static DEFINE_PER_CPU(int, ipi_dev);
+
 int smp_ipi_irq_setup(int cpu, int irq)
 {
-       int *dev_id = &per_cpu(ipi_dev, smp_processor_id());
-       return request_percpu_irq(irq, do_IPI, "IPI Interrupt", dev_id);
+       int *dev = per_cpu_ptr(&ipi_dev, cpu);
+
+       arc_request_percpu_irq(irq, cpu, do_IPI, "IPI Interrupt", dev);
+
+       return 0;
 }

diff --git a/arch/arc/kernel/time.c b/arch/arc/kernel/time.c
index 71c42521c77ff0eaa0a17e6a52299839db35bb40..5190553357694220cc7f25bfc9acb29a7de6d95d 100644 (file)
--- a/arch/arc/kernel/time.c
+++ b/arch/arc/kernel/time.c
@@ -210,32 +210,19 @@ static irqreturn_t timer_irq_handler(int irq, void *dev_id)
        return IRQ_HANDLED;
 }
 
-static struct irqaction arc_timer_irq = {
-       .name    = "Timer0 (clock-evt-dev)",
-       .flags   = IRQF_TIMER | IRQF_PERCPU,
-       .handler = timer_irq_handler,
-};
-
 /*
  * Setup the local event timer for @cpu
  */
 void arc_local_timer_setup(unsigned int cpu)
 {
-       struct clock_event_device *clk = &per_cpu(arc_clockevent_device, cpu);
+       struct clock_event_device *evt = per_cpu_ptr(&arc_clockevent_device, cpu);
 
-       clk->cpumask = cpumask_of(cpu);
-       clockevents_config_and_register(clk, arc_get_core_freq(),
+       evt->cpumask = cpumask_of(cpu);
+       clockevents_config_and_register(evt, arc_get_core_freq(),
                                        0, ARC_TIMER_MAX);
 
-       /*
-        * setup the per-cpu timer IRQ handler - for all cpus
-        * For non boot CPU explicitly unmask at intc
-        * setup_irq() -> .. -> irq_startup() already does this on boot-cpu
-        */
-       if (!cpu)
-               setup_irq(TIMER0_IRQ, &arc_timer_irq);
-       else
-               arch_unmask_irq(TIMER0_IRQ);
+       arc_request_percpu_irq(TIMER0_IRQ, cpu, timer_irq_handler,
+                              "Timer0 (per-cpu-tick)", evt);
 }
 
 /*