3 files changed, 75 insertions, 26 deletions

diff --git a/arch/sh/include/asm/irq.h b/arch/sh/include/asm/irq.h
index df8e1500527c..99c593b3a827 100644
--- a/arch/sh/include/asm/irq.h
+++ b/arch/sh/include/asm/irq.h
@@ -12,6 +12,14 @@
 #define NR_IRQS_LEGACY          8       /* Legacy external IRQ0-7 */
 
 /*
+ * This is a special IRQ number for indicating that no IRQ has been
+ * triggered and to simply ignore the IRQ dispatch. This is a special
+ * case that can happen with IRQ auto-distribution when multiple CPUs
+ * are woken up and signalled in parallel.
+ */
+#define NO_IRQ_IGNORE           ((unsigned int)-1)
+
+/*
  * Convert back and forth between INTEVT and IRQ values.
  */
 #ifdef CONFIG_CPU_HAS_INTEVT
@@ -53,6 +61,14 @@ extern void irq_ctx_exit(int cpu);
 # define irq_ctx_exit(cpu) do { } while (0)
 #endif
 
+#ifdef CONFIG_INTC_BALANCING
+extern unsigned int irq_lookup(unsigned int irq);
+extern void irq_finish(unsigned int irq);
+#else
+#define irq_lookup(irq)         (irq)
+#define irq_finish(irq)         do { } while (0)
+#endif
+
 #include <asm-generic/irq.h>
 #ifdef CONFIG_CPU_SH5
 #include <cpu/irq.h>
diff --git a/arch/sh/kernel/cpu/sh4a/setup-sh7786.c b/arch/sh/kernel/cpu/sh4a/setup-sh7786.c
index 235edf8065df..d7336036d04d 100644
--- a/arch/sh/kernel/cpu/sh4a/setup-sh7786.c
+++ b/arch/sh/kernel/cpu/sh4a/setup-sh7786.c
@@ -573,7 +573,6 @@ static struct platform_device *sh7786_devices[] __initdata = {
         &usb_ohci_device,
 };
 
-
 /*
  * Please call this function if your platform board
  * use external clock for USB
@@ -581,6 +580,7 @@ static struct platform_device *sh7786_devices[] __initdata = {
 #define USBCTL0         0xffe70858
 #define CLOCK_MODE_MASK 0xffffff7f
 #define EXT_CLOCK_MODE  0x00000080
+
 void __init sh7786_usb_use_exclock(void)
 {
         u32 val = __raw_readl(USBCTL0) & CLOCK_MODE_MASK;
@@ -598,6 +598,7 @@ void __init sh7786_usb_use_exclock(void)
 #define PLL_ENB         0x00000002
 #define PHY_RST         0x00000004
 #define ACT_PLL_STATUS  0xc0000000
+
 static void __init sh7786_usb_setup(void)
 {
         int i = 1000000;
@@ -753,9 +754,19 @@ static struct intc_vect vectors[] __initdata = {
 #define INTMSK2         0xfe410068
 #define INTMSKCLR2      0xfe41006c
 
+#define INTDISTCR0      0xfe4100b0
+#define INTDISTCR1      0xfe4100b4
+#define INTACK          0xfe4100b8
+#define INTACKCLR       0xfe4100bc
+#define INT2DISTCR0     0xfe410900
+#define INT2DISTCR1     0xfe410904
+#define INT2DISTCR2     0xfe410908
+#define INT2DISTCR3     0xfe41090c
+
 static struct intc_mask_reg mask_registers[] __initdata = {
         { CnINTMSK0, CnINTMSKCLR0, 32,
-          { IRQ0, IRQ1, IRQ2, IRQ3, IRQ4, IRQ5, IRQ6, IRQ7 } },
+          { IRQ0, IRQ1, IRQ2, IRQ3, IRQ4, IRQ5, IRQ6, IRQ7 },
+            INTC_SMP_BALANCING(INTDISTCR0) },
         { INTMSK2, INTMSKCLR2, 32,
           { IRL0_LLLL, IRL0_LLLH, IRL0_LLHL, IRL0_LLHH,
             IRL0_LHLL, IRL0_LHLH, IRL0_LHHL, IRL0_LHHH,
@@ -767,7 +778,8 @@ static struct intc_mask_reg mask_registers[] __initdata = {
             IRL4_HHLL, IRL4_HHLH, IRL4_HHHL, 0, } },
         { CnINT2MSKR0, CnINT2MSKCR0 , 32,
           { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
-            0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, WDT } },
+            0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, WDT },
+            INTC_SMP_BALANCING(INT2DISTCR0) },
         { CnINT2MSKR1, CnINT2MSKCR1, 32,
           { TMU0_0, TMU0_1, TMU0_2, TMU0_3, TMU1_0, TMU1_1, TMU1_2, 0,
             DMAC0_0, DMAC0_1, DMAC0_2, DMAC0_3, DMAC0_4, DMAC0_5, DMAC0_6,
@@ -776,14 +788,14 @@ static struct intc_mask_reg mask_registers[] __initdata = {
             HPB_0, HPB_1, HPB_2,
             SCIF0_0, SCIF0_1, SCIF0_2, SCIF0_3,
             SCIF1,
-            TMU2, TMU3, 0, } },
+            TMU2, TMU3, 0, }, INTC_SMP_BALANCING(INT2DISTCR1) },
         { CnINT2MSKR2, CnINT2MSKCR2, 32,
           { 0, 0, SCIF2, SCIF3, SCIF4, SCIF5,
             Eth_0, Eth_1,
             0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
             PCIeC0_0, PCIeC0_1, PCIeC0_2,
             PCIeC1_0, PCIeC1_1, PCIeC1_2,
-            USB, 0, 0 } },
+            USB, 0, 0 }, INTC_SMP_BALANCING(INT2DISTCR2) },
         { CnINT2MSKR3, CnINT2MSKCR3, 32,
           { 0, 0, 0, 0, 0, 0,
             I2C0, I2C1,
@@ -792,7 +804,7 @@ static struct intc_mask_reg mask_registers[] __initdata = {
             HAC0, HAC1,
             FLCTL, 0,
             HSPI, GPIO0, GPIO1, Thermal,
-            0, 0, 0, 0, 0, 0, 0, 0 } },
+            0, 0, 0, 0, 0, 0, 0, 0 }, INTC_SMP_BALANCING(INT2DISTCR3) },
 };
 
 static struct intc_prio_reg prio_registers[] __initdata = {
@@ -910,6 +922,18 @@ static DECLARE_INTC_DESC(intc_desc_irl4567, "sh7786-irl4567", vectors_irl4567,
 #define INTC_INTMSKCLR2 INTMSKCLR2
 #define INTC_USERIMASK  0xfe411000
 
+#ifdef CONFIG_INTC_BALANCING
+unsigned int irq_lookup(unsigned int irq)
+{
+        return __raw_readl(INTACK) & 1 ? irq : NO_IRQ_IGNORE;
+}
+
+void irq_finish(unsigned int irq)
+{
+        __raw_writel(irq2evt(irq), INTACKCLR);
+}
+#endif
+
 void __init plat_irq_setup(void)
 {
         /* disable IRQ3-0 + IRQ7-4 */
diff --git a/arch/sh/kernel/irq.c b/arch/sh/kernel/irq.c
index d2d41d046657..f6a9319c28e2 100644
--- a/arch/sh/kernel/irq.c
+++ b/arch/sh/kernel/irq.c
@@ -113,19 +113,14 @@ union irq_ctx {
 
 static union irq_ctx *hardirq_ctx[NR_CPUS] __read_mostly;
 static union irq_ctx *softirq_ctx[NR_CPUS] __read_mostly;
-#endif
 
-asmlinkage __irq_entry int do_IRQ(unsigned int irq, struct pt_regs *regs)
+static char softirq_stack[NR_CPUS * THREAD_SIZE] __page_aligned_bss;
+static char hardirq_stack[NR_CPUS * THREAD_SIZE] __page_aligned_bss;
+
+static inline void handle_one_irq(unsigned int irq)
 {
-        struct pt_regs *old_regs = set_irq_regs(regs);
-#ifdef CONFIG_IRQSTACKS
         union irq_ctx *curctx, *irqctx;
-#endif
-
-        irq_enter();
-        irq = irq_demux(irq);
 
-#ifdef CONFIG_IRQSTACKS
         curctx = (union irq_ctx *)current_thread_info();
         irqctx = hardirq_ctx[smp_processor_id()];
 
@@ -164,20 +159,9 @@ asmlinkage __irq_entry int do_IRQ(unsigned int irq, struct pt_regs *regs)
                           "r5", "r6", "r7", "r8", "t", "pr"
                 );
         } else
-#endif
                 generic_handle_irq(irq);
-
-        irq_exit();
-
-        set_irq_regs(old_regs);
-        return 1;
 }
 
-#ifdef CONFIG_IRQSTACKS
-static char softirq_stack[NR_CPUS * THREAD_SIZE] __page_aligned_bss;
-
-static char hardirq_stack[NR_CPUS * THREAD_SIZE] __page_aligned_bss;
-
 /*
  * allocate per-cpu stacks for hardirq and for softirq processing
  */
@@ -257,8 +241,33 @@ asmlinkage void do_softirq(void)
 
         local_irq_restore(flags);
 }
+#else
+static inline void handle_one_irq(unsigned int irq)
+{
+        generic_handle_irq(irq);
+}
 #endif
 
+asmlinkage __irq_entry int do_IRQ(unsigned int irq, struct pt_regs *regs)
+{
+        struct pt_regs *old_regs = set_irq_regs(regs);
+
+        irq_enter();
+
+        irq = irq_demux(irq_lookup(irq));
+
+        if (irq != NO_IRQ_IGNORE) {
+                handle_one_irq(irq);
+                irq_finish(irq);
+        }
+
+        irq_exit();
+
+        set_irq_regs(old_regs);
+
+        return IRQ_HANDLED;
+}
+
 void __init init_IRQ(void)
 {
         plat_irq_setup();