MIPS: Alchemy: chain IRQ controllers to MIPS IRQ controller

IC and GPIC are now chain handlers of the traditional MIPS IRQ controller.

Signed-off-by: Manuel Lauss <manuel.lauss@googlemail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2933/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

2 files changed, 39 insertions, 49 deletions

diff --git a/arch/mips/alchemy/common/gpioint.c b/arch/mips/alchemy/common/gpioint.c
index 5d7729a59908..daaaab09044a 100644
--- a/arch/mips/alchemy/common/gpioint.c
+++ b/arch/mips/alchemy/common/gpioint.c
@@ -349,6 +349,12 @@ static struct syscore_ops alchemy_gpic_pmops = {
         .resume         = alchemy_gpic_resume,
 };
 
+static void alchemy_gpic_dispatch(unsigned int irq, struct irq_desc *d)
+{
+        int i = __raw_readl(AU1300_GPIC_ADDR + AU1300_GPIC_PRIENC);
+        generic_handle_irq(ALCHEMY_GPIC_INT_BASE + i);
+}
+
 static void __init alchemy_gpic_init_irq(const struct gpic_devint_data *dints)
 {
         int i;
@@ -383,7 +389,10 @@ static void __init alchemy_gpic_init_irq(const struct gpic_devint_data *dints)
                 dints++;
         }
 
-        set_c0_status(IE_IRQ0 | IE_IRQ1 | IE_IRQ2 | IE_IRQ3);
+        irq_set_chained_handler(MIPS_CPU_IRQ_BASE + 2, alchemy_gpic_dispatch);
+        irq_set_chained_handler(MIPS_CPU_IRQ_BASE + 3, alchemy_gpic_dispatch);
+        irq_set_chained_handler(MIPS_CPU_IRQ_BASE + 4, alchemy_gpic_dispatch);
+        irq_set_chained_handler(MIPS_CPU_IRQ_BASE + 5, alchemy_gpic_dispatch);
 }
 
 /**********************************************************************/
@@ -397,17 +406,8 @@ void __init arch_init_irq(void)
         }
 }
 
-#define CAUSEF_GPIC (CAUSEF_IP2 | CAUSEF_IP3 | CAUSEF_IP4 | CAUSEF_IP5)
-
-void plat_irq_dispatch(void)
+asmlinkage void plat_irq_dispatch(void)
 {
-        unsigned long i, c = read_c0_cause() & read_c0_status();
-
-        if (c & CAUSEF_IP7)                             /* c0 timer */
-                do_IRQ(MIPS_CPU_IRQ_BASE + 7);
-        else if (likely(c & CAUSEF_GPIC)) {
-                i = __raw_readl(AU1300_GPIC_ADDR + AU1300_GPIC_PRIENC);
-                do_IRQ(i + ALCHEMY_GPIC_INT_BASE);
-        } else
-                spurious_interrupt();
+        unsigned long r = (read_c0_status() & read_c0_cause()) >> 8;
+        do_IRQ(MIPS_CPU_IRQ_BASE + __ffs(r & 0xff));
 }
diff --git a/arch/mips/alchemy/common/irq.c b/arch/mips/alchemy/common/irq.c
index f206e24961c5..ee80a32f5ef9 100644
--- a/arch/mips/alchemy/common/irq.c
+++ b/arch/mips/alchemy/common/irq.c
@@ -459,41 +459,6 @@ static int au1x_ic_settype(struct irq_data *d, unsigned int flow_type)
         return ret;
 }
 
-asmlinkage void plat_irq_dispatch(void)
-{
-        unsigned int pending = read_c0_status() & read_c0_cause();
-        unsigned long s, off;
-
-        if (pending & CAUSEF_IP7) {
-                off = MIPS_CPU_IRQ_BASE + 7;
-                goto handle;
-        } else if (pending & CAUSEF_IP2) {
-                s = KSEG1ADDR(AU1000_IC0_PHYS_ADDR) + IC_REQ0INT;
-                off = AU1000_INTC0_INT_BASE;
-        } else if (pending & CAUSEF_IP3) {
-                s = KSEG1ADDR(AU1000_IC0_PHYS_ADDR) + IC_REQ1INT;
-                off = AU1000_INTC0_INT_BASE;
-        } else if (pending & CAUSEF_IP4) {
-                s = KSEG1ADDR(AU1000_IC1_PHYS_ADDR) + IC_REQ0INT;
-                off = AU1000_INTC1_INT_BASE;
-        } else if (pending & CAUSEF_IP5) {
-                s = KSEG1ADDR(AU1000_IC1_PHYS_ADDR) + IC_REQ1INT;
-                off = AU1000_INTC1_INT_BASE;
-        } else
-                goto spurious;
-
-        s = __raw_readl((void __iomem *)s);
-        if (unlikely(!s)) {
-spurious:
-                spurious_interrupt();
-                return;
-        }
-        off += __ffs(s);
-handle:
-        do_IRQ(off);
-}
-
-
 static inline void ic_init(void __iomem *base)
 {
         /* initialize interrupt controller to a safe state */
@@ -562,6 +527,22 @@ static struct syscore_ops alchemy_ic_syscore_ops = {
         .resume         = alchemy_ic_resume,
 };
 
+/* create chained handlers for the 4 IC requests to the MIPS IRQ ctrl */
+#define DISP(name, base, addr)                                                \
+static void au1000_##name##_dispatch(unsigned int irq, struct irq_desc *d)    \
+{                                                                             \
+        unsigned long r = __raw_readl((void __iomem *)KSEG1ADDR(addr));       \
+        if (likely(r))                                                        \
+                generic_handle_irq(base + __ffs(r));                          \
+        else                                                                  \
+                spurious_interrupt();                                         \
+}
+
+DISP(ic0r0, AU1000_INTC0_INT_BASE, AU1000_IC0_PHYS_ADDR + IC_REQ0INT)
+DISP(ic0r1, AU1000_INTC0_INT_BASE, AU1000_IC0_PHYS_ADDR + IC_REQ1INT)
+DISP(ic1r0, AU1000_INTC1_INT_BASE, AU1000_IC1_PHYS_ADDR + IC_REQ0INT)
+DISP(ic1r1, AU1000_INTC1_INT_BASE, AU1000_IC1_PHYS_ADDR + IC_REQ1INT)
+
 static void __init au1000_init_irq(struct au1xxx_irqmap *map)
 {
         unsigned int bit, irq_nr;
@@ -603,7 +584,10 @@ static void __init au1000_init_irq(struct au1xxx_irqmap *map)
                 ++map;
         }
 
-        set_c0_status(IE_IRQ0 | IE_IRQ1 | IE_IRQ2 | IE_IRQ3);
+        irq_set_chained_handler(MIPS_CPU_IRQ_BASE + 2, au1000_ic0r0_dispatch);
+        irq_set_chained_handler(MIPS_CPU_IRQ_BASE + 3, au1000_ic0r1_dispatch);
+        irq_set_chained_handler(MIPS_CPU_IRQ_BASE + 4, au1000_ic1r0_dispatch);
+        irq_set_chained_handler(MIPS_CPU_IRQ_BASE + 5, au1000_ic1r1_dispatch);
 }
 
 void __init arch_init_irq(void)
@@ -626,3 +610,9 @@ void __init arch_init_irq(void)
                 break;
         }
 }
+
+asmlinkage void plat_irq_dispatch(void)
+{
+        unsigned long r = (read_c0_status() & read_c0_cause()) >> 8;
+        do_IRQ(MIPS_CPU_IRQ_BASE + __ffs(r & 0xff));
+}