MIPS: Alchemy: devboards: factor out PB1200 IRQ cascade code.

Move the PB1200 IRQ cascade code out to the BCSR support code:
upcoming DB1300 support can use it too.

Signed-off-by: Manuel Lauss <manuel.lauss@gmail.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

2 files changed, 73 insertions, 70 deletions

diff --git a/arch/mips/alchemy/devboards/bcsr.c b/arch/mips/alchemy/devboards/bcsr.c
index 85b7715901af..3bc4fd2155d7 100644
--- a/arch/mips/alchemy/devboards/bcsr.c
+++ b/arch/mips/alchemy/devboards/bcsr.c
@@ -7,6 +7,7 @@
  * All registers are 16bits wide with 32bit spacing.
  */
 
+#include <linux/interrupt.h>
 #include <linux/module.h>
 #include <linux/spinlock.h>
 #include <asm/addrspace.h>
@@ -18,6 +19,9 @@ static struct bcsr_reg {
         spinlock_t lock;
 } bcsr_regs[BCSR_CNT];
 
+static void __iomem *bcsr_virt; /* KSEG1 addr of BCSR base */
+static int bcsr_csc_base;       /* linux-irq of first cascaded irq */
+
 void __init bcsr_init(unsigned long bcsr1_phys, unsigned long bcsr2_phys)
 {
         int i;
@@ -25,6 +29,8 @@ void __init bcsr_init(unsigned long bcsr1_phys, unsigned long bcsr2_phys)
         bcsr1_phys = KSEG1ADDR(CPHYSADDR(bcsr1_phys));
         bcsr2_phys = KSEG1ADDR(CPHYSADDR(bcsr2_phys));
 
+        bcsr_virt = (void __iomem *)bcsr1_phys;
+
         for (i = 0; i < BCSR_CNT; i++) {
                 if (i >= BCSR_HEXLEDS)
                         bcsr_regs[i].raddr = (void __iomem *)bcsr2_phys +
@@ -74,3 +80,69 @@ void bcsr_mod(enum bcsr_id reg, unsigned short clr, unsigned short set)
         spin_unlock_irqrestore(&bcsr_regs[reg].lock, flags);
 }
 EXPORT_SYMBOL_GPL(bcsr_mod);
+
+/*
+ * DB1200/PB1200 CPLD IRQ muxer
+ */
+static void bcsr_csc_handler(unsigned int irq, struct irq_desc *d)
+{
+        unsigned short bisr = __raw_readw(bcsr_virt + BCSR_REG_INTSTAT);
+
+        for ( ; bisr; bisr &= bisr - 1)
+                generic_handle_irq(bcsr_csc_base + __ffs(bisr));
+}
+
+/* NOTE: both the enable and mask bits must be cleared, otherwise the
+ * CPLD generates tons of spurious interrupts (at least on my DB1200).
+ *      -- mlau
+ */
+static void bcsr_irq_mask(unsigned int irq_nr)
+{
+        unsigned short v = 1 << (irq_nr - bcsr_csc_base);
+        __raw_writew(v, bcsr_virt + BCSR_REG_INTCLR);
+        __raw_writew(v, bcsr_virt + BCSR_REG_MASKCLR);
+        wmb();
+}
+
+static void bcsr_irq_maskack(unsigned int irq_nr)
+{
+        unsigned short v = 1 << (irq_nr - bcsr_csc_base);
+        __raw_writew(v, bcsr_virt + BCSR_REG_INTCLR);
+        __raw_writew(v, bcsr_virt + BCSR_REG_MASKCLR);
+        __raw_writew(v, bcsr_virt + BCSR_REG_INTSTAT);  /* ack */
+        wmb();
+}
+
+static void bcsr_irq_unmask(unsigned int irq_nr)
+{
+        unsigned short v = 1 << (irq_nr - bcsr_csc_base);
+        __raw_writew(v, bcsr_virt + BCSR_REG_INTSET);
+        __raw_writew(v, bcsr_virt + BCSR_REG_MASKSET);
+        wmb();
+}
+
+static struct irq_chip bcsr_irq_type = {
+        .name           = "CPLD",
+        .mask           = bcsr_irq_mask,
+        .mask_ack       = bcsr_irq_maskack,
+        .unmask         = bcsr_irq_unmask,
+};
+
+void __init bcsr_init_irq(int csc_start, int csc_end, int hook_irq)
+{
+        unsigned int irq;
+
+        /* mask & disable & ack all */
+        __raw_writew(0xffff, bcsr_virt + BCSR_REG_INTCLR);
+        __raw_writew(0xffff, bcsr_virt + BCSR_REG_MASKCLR);
+        __raw_writew(0xffff, bcsr_virt + BCSR_REG_INTSTAT);
+        wmb();
+
+        bcsr_csc_base = csc_start;
+
+        for (irq = csc_start; irq <= csc_end; irq++)
+                set_irq_chip_and_handler_name(irq, &bcsr_irq_type,
+                        handle_level_irq, "level");
+
+        set_irq_chained_handler(hook_irq, bcsr_csc_handler);
+}
diff --git a/arch/mips/alchemy/devboards/pb1200/irqmap.c b/arch/mips/alchemy/devboards/pb1200/irqmap.c
index f379b02213f1..3beb8046667b 100644
--- a/arch/mips/alchemy/devboards/pb1200/irqmap.c
+++ b/arch/mips/alchemy/devboards/pb1200/irqmap.c
@@ -45,69 +45,11 @@ struct au1xxx_irqmap __initdata au1xxx_irq_map[] = {
         { AU1000_GPIO_7, IRQF_TRIGGER_LOW, 0 },
 };
 
-static void __iomem *bcsr_virt;
-
-/*
- * Support for External interrupts on the Pb1200 Development platform.
- */
-
-static void pb1200_cascade_handler(unsigned int irq, struct irq_desc *d)
-{
-        unsigned short bisr = __raw_readw(bcsr_virt + BCSR_REG_INTSTAT);
-
-        for ( ; bisr; bisr &= bisr - 1)
-                generic_handle_irq(PB1200_INT_BEGIN + __ffs(bisr));
-}
-
-/* NOTE: both the enable and mask bits must be cleared, otherwise the
- * CPLD generates tons of spurious interrupts (at least on the DB1200).
- */
-static void pb1200_mask_irq(unsigned int irq_nr)
-{
-        unsigned short v = 1 << (irq_nr - PB1200_INT_BEGIN);
-        __raw_writew(v, bcsr_virt + BCSR_REG_INTCLR);
-        __raw_writew(v, bcsr_virt + BCSR_REG_MASKCLR);
-        wmb();
-}
-
-static void pb1200_maskack_irq(unsigned int irq_nr)
-{
-        unsigned short v = 1 << (irq_nr - PB1200_INT_BEGIN);
-        __raw_writew(v, bcsr_virt + BCSR_REG_INTCLR);
-        __raw_writew(v, bcsr_virt + BCSR_REG_MASKCLR);
-        __raw_writew(v, bcsr_virt + BCSR_REG_INTSTAT);  /* ack */
-        wmb();
-}
-
-static void pb1200_unmask_irq(unsigned int irq_nr)
-{
-        unsigned short v = 1 << (irq_nr - PB1200_INT_BEGIN);
-        __raw_writew(v, bcsr_virt + BCSR_REG_INTSET);
-        __raw_writew(v, bcsr_virt + BCSR_REG_MASKSET);
-        wmb();
-}
-
-static struct irq_chip pb1200_cpld_irq_type = {
-#ifdef CONFIG_MIPS_PB1200
-        .name = "Pb1200 Ext",
-#endif
-#ifdef CONFIG_MIPS_DB1200
-        .name = "Db1200 Ext",
-#endif
-        .mask           = pb1200_mask_irq,
-        .mask_ack       = pb1200_maskack_irq,
-        .unmask         = pb1200_unmask_irq,
-};
-
 void __init board_init_irq(void)
 {
-        unsigned int irq;
-
         au1xxx_setup_irqmap(au1xxx_irq_map, ARRAY_SIZE(au1xxx_irq_map));
 
 #ifdef CONFIG_MIPS_PB1200
-        bcsr_virt = (void __iomem *)KSEG1ADDR(PB1200_BCSR_PHYS_ADDR);
-
         /* We have a problem with CPLD rev 3. */
         if (BCSR_WHOAMI_CPLD(bcsr_read(BCSR_WHOAMI)) <= 3) {
                 printk(KERN_ERR "WARNING!!!\n");
@@ -127,18 +69,7 @@ void __init board_init_irq(void)
                 printk(KERN_ERR "WARNING!!!\n");
                 panic("Game over.  Your score is 0.");
         }
-#else
-        bcsr_virt = (void __iomem *)KSEG1ADDR(DB1200_BCSR_PHYS_ADDR);
 #endif
 
-        /* mask & disable & ack all */
-        bcsr_write(BCSR_INTCLR, 0xffff);
-        bcsr_write(BCSR_MASKCLR, 0xffff);
-        bcsr_write(BCSR_INTSTAT, 0xffff);
-
-        for (irq = PB1200_INT_BEGIN; irq <= PB1200_INT_END; irq++)
-                set_irq_chip_and_handler_name(irq, &pb1200_cpld_irq_type,
-                                         handle_level_irq, "level");
-
-        set_irq_chained_handler(AU1000_GPIO_7, pb1200_cascade_handler);
+        bcsr_init_irq(PB1200_INT_BEGIN, PB1200_INT_END, AU1000_GPIO_7);
 }