[PATCH 08/11] MIPS: BCM63XX: prepare irq code to handle different external irq hardware implementation.

[Maxime Bizon <mbizon@freebox.fr>]

External irq only works for 6348, change code to prepare support of
other CPUs.

Signed-off-by: Maxime Bizon <mbizon@freebox.fr>
---
 arch/mips/bcm63xx/irq.c |   77 ++++++++++++++++++++++++++++++++++++----------
 1 files changed, 60 insertions(+), 17 deletions(-)

diff --git a/arch/mips/bcm63xx/irq.c b/arch/mips/bcm63xx/irq.c
index d002831..2e4f317 100644
--- a/arch/mips/bcm63xx/irq.c
+++ b/arch/mips/bcm63xx/irq.c
@@ -25,18 +25,32 @@ static void __dispatch_internal(void) __maybe_unused;
 #ifdef CONFIG_BCM63XX_CPU_6338
 #define irq_stat_reg           PERF_IRQSTAT_6338_REG
 #define irq_mask_reg           PERF_IRQMASK_6338_REG
+#define is_ext_irq_cascaded    0
+#define ext_irq_start          0
+#define ext_irq_end            0
 #endif
 #ifdef CONFIG_BCM63XX_CPU_6345
 #define irq_stat_reg           PERF_IRQSTAT_6345_REG
 #define irq_mask_reg           PERF_IRQMASK_6345_REG
+#define is_ext_irq_cascaded    0
+#define ext_irq_start          0
+#define ext_irq_end            0
 #endif
 #ifdef CONFIG_BCM63XX_CPU_6348
 #define irq_stat_reg           PERF_IRQSTAT_6348_REG
 #define irq_mask_reg           PERF_IRQMASK_6348_REG
+#define dispatch_internal      __dispatch_internal
+#define is_ext_irq_cascaded    0
+#define ext_irq_start          0
+#define ext_irq_end            0
 #endif
 #ifdef CONFIG_BCM63XX_CPU_6358
 #define irq_stat_reg           PERF_IRQSTAT_6358_REG
 #define irq_mask_reg           PERF_IRQMASK_6358_REG
+#define dispatch_internal      __dispatch_internal
+#define is_ext_irq_cascaded    1
+#define ext_irq_start          (BCM_6358_EXT_IRQ0 - IRQ_INTERNAL_BASE)
+#define ext_irq_end            (BCM_6358_EXT_IRQ3 - IRQ_INTERNAL_BASE)
 #endif
 
 #define dispatch_internal      __dispatch_internal
@@ -51,6 +65,8 @@ static inline void bcm63xx_init_irq(void)
 
 static u32 irq_stat_addr, irq_mask_addr;
 static void (*dispatch_internal)(void);
+static int is_ext_irq_cascaded;
+static unsigned int ext_irq_start, ext_irq_end;
 
 static void bcm63xx_init_irq(void)
 {
@@ -73,6 +89,9 @@ static void bcm63xx_init_irq(void)
        case BCM6358_CPU_ID:
                irq_stat_addr += PERF_IRQSTAT_6358_REG;
                irq_mask_addr += PERF_IRQMASK_6358_REG;
+               is_ext_irq_cascaded = 1;
+               ext_irq_start = BCM_6358_EXT_IRQ0 - IRQ_INTERNAL_BASE;
+               ext_irq_end = BCM_6358_EXT_IRQ3 - IRQ_INTERNAL_BASE;
                break;
        default:
                BUG();
@@ -84,7 +103,11 @@ static void bcm63xx_init_irq(void)
 
 static inline void handle_internal(int intbit)
 {
-       do_IRQ(intbit + IRQ_INTERNAL_BASE);
+       if (is_ext_irq_cascaded &&
+           intbit >= ext_irq_start && intbit <= ext_irq_end)
+               do_IRQ(intbit - ext_irq_start + IRQ_EXT_BASE);
+       else
+               do_IRQ(intbit + IRQ_INTERNAL_BASE);
 }
 
 /*
@@ -128,14 +151,16 @@ asmlinkage void plat_irq_dispatch(void)
                        do_IRQ(7);
                if (cause & CAUSEF_IP2)
                        dispatch_internal();
-               if (cause & CAUSEF_IP3)
-                       do_IRQ(IRQ_EXT_0);
-               if (cause & CAUSEF_IP4)
-                       do_IRQ(IRQ_EXT_1);
-               if (cause & CAUSEF_IP5)
-                       do_IRQ(IRQ_EXT_2);
-               if (cause & CAUSEF_IP6)
-                       do_IRQ(IRQ_EXT_3);
+               if (!is_ext_irq_cascaded) {
+                       if (cause & CAUSEF_IP3)
+                               do_IRQ(IRQ_EXT_0);
+                       if (cause & CAUSEF_IP4)
+                               do_IRQ(IRQ_EXT_1);
+                       if (cause & CAUSEF_IP5)
+                               do_IRQ(IRQ_EXT_2);
+                       if (cause & CAUSEF_IP6)
+                               do_IRQ(IRQ_EXT_3);
+               }
        } while (1);
 }
 
@@ -143,9 +168,8 @@ asmlinkage void plat_irq_dispatch(void)
  * internal IRQs operations: only mask/unmask on PERF irq mask
  * register.
  */
-static inline void bcm63xx_internal_irq_mask(struct irq_data *d)
+static void internal_irq_mask(unsigned int irq)
 {
-       unsigned int irq = d->irq - IRQ_INTERNAL_BASE;
        u32 mask;
 
        mask = bcm_readl(irq_mask_addr);
@@ -153,9 +177,8 @@ static inline void bcm63xx_internal_irq_mask(struct 
irq_data *d)
        bcm_writel(mask, irq_mask_addr);
 }
 
-static void bcm63xx_internal_irq_unmask(struct irq_data *d)
+static void internal_irq_unmask(unsigned int irq)
 {
-       unsigned int irq = d->irq - IRQ_INTERNAL_BASE;
        u32 mask;
 
        mask = bcm_readl(irq_mask_addr);
@@ -163,6 +186,16 @@ static void bcm63xx_internal_irq_unmask(struct irq_data *d)
        bcm_writel(mask, irq_mask_addr);
 }
 
+static void bcm63xx_internal_irq_mask(struct irq_data *d)
+{
+       internal_irq_mask(d->irq - IRQ_INTERNAL_BASE);
+}
+
+static void bcm63xx_internal_irq_unmask(struct irq_data *d)
+{
+       internal_irq_unmask(d->irq - IRQ_INTERNAL_BASE);
+}
+
 /*
  * external IRQs operations: mask/unmask and clear on PERF external
  * irq control register.
@@ -175,6 +208,8 @@ static void bcm63xx_external_irq_mask(struct irq_data *d)
        reg = bcm_perf_readl(PERF_EXTIRQ_CFG_REG);
        reg &= ~EXTIRQ_CFG_MASK(irq);
        bcm_perf_writel(reg, PERF_EXTIRQ_CFG_REG);
+       if (is_ext_irq_cascaded)
+               internal_irq_mask(irq + ext_irq_start);
 }
 
 static void bcm63xx_external_irq_unmask(struct irq_data *d)
@@ -185,6 +220,8 @@ static void bcm63xx_external_irq_unmask(struct irq_data *d)
        reg = bcm_perf_readl(PERF_EXTIRQ_CFG_REG);
        reg |= EXTIRQ_CFG_MASK(irq);
        bcm_perf_writel(reg, PERF_EXTIRQ_CFG_REG);
+       if (is_ext_irq_cascaded)
+               internal_irq_unmask(irq + ext_irq_start);
 }
 
 static void bcm63xx_external_irq_clear(struct irq_data *d)
@@ -195,12 +232,16 @@ static void bcm63xx_external_irq_clear(struct irq_data *d)
        reg = bcm_perf_readl(PERF_EXTIRQ_CFG_REG);
        reg |= EXTIRQ_CFG_CLEAR(irq);
        bcm_perf_writel(reg, PERF_EXTIRQ_CFG_REG);
+       if (is_ext_irq_cascaded)
+               internal_irq_mask(irq + ext_irq_start);
 }
 
 static unsigned int bcm63xx_external_irq_startup(struct irq_data *d)
 {
-       set_c0_status(0x100 << (d->irq - IRQ_MIPS_BASE));
-       irq_enable_hazard();
+       if (!is_ext_irq_cascaded) {
+               set_c0_status(0x100 << (d->irq - IRQ_MIPS_BASE));
+               irq_enable_hazard();
+       }
        bcm63xx_external_irq_unmask(d);
        return 0;
 }
@@ -208,8 +249,10 @@ static unsigned int bcm63xx_external_irq_startup(struct 
irq_data *d)
 static void bcm63xx_external_irq_shutdown(struct irq_data *d)
 {
        bcm63xx_external_irq_mask(d);
-       clear_c0_status(0x100 << (d->irq - IRQ_MIPS_BASE));
-       irq_disable_hazard();
+       if (!is_ext_irq_cascaded) {
+               clear_c0_status(0x100 << (d->irq - IRQ_MIPS_BASE));
+               irq_disable_hazard();
+       }
 }
 
 static int bcm63xx_external_irq_set_type(struct irq_data *d,
-- 
1.7.1.1