MIPS: Alchemy: pb1200: update CPLD cascade irq handler.

Tested on Db1200.

Signed-off-by: Manuel Lauss <mano@roarinelk.homelinux.net>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

diff --git a/arch/mips/alchemy/devboards/pb1200/irqmap.c b/arch/mips/alchemy/devboards/pb1200/irqmap.c
index 1f92fec..fe47498 100644 (file)
--- a/arch/mips/alchemy/devboards/pb1200/irqmap.c
+++ b/arch/mips/alchemy/devboards/pb1200/irqmap.c
@@ -47,77 +47,50 @@ struct au1xxx_irqmap __initdata au1xxx_irq_map[] = {
 /*
  * Support for External interrupts on the Pb1200 Development platform.
  */
-static volatile int pb1200_cascade_en;
 
-irqreturn_t pb1200_cascade_handler(int irq, void *dev_id)
+static void pb1200_cascade_handler(unsigned int irq, struct irq_desc *d)
 {
        unsigned short bisr = bcsr->int_status;
-       int extirq_nr = 0;
-
-       /* Clear all the edge interrupts. This has no effect on level. */
-       bcsr->int_status = bisr;
-       for ( ; bisr; bisr &= bisr - 1) {
-               extirq_nr = PB1200_INT_BEGIN + __ffs(bisr);
-               /* Ack and dispatch IRQ */
-               do_IRQ(extirq_nr);
-       }
-
-       return IRQ_RETVAL(1);
-}
 
-inline void pb1200_enable_irq(unsigned int irq_nr)
-{
-       bcsr->intset_mask = 1 << (irq_nr - PB1200_INT_BEGIN);
-       bcsr->intset = 1 << (irq_nr - PB1200_INT_BEGIN);
+       for ( ; bisr; bisr &= bisr - 1)
+               generic_handle_irq(PB1200_INT_BEGIN + __ffs(bisr));
 }
 
-inline void pb1200_disable_irq(unsigned int irq_nr)
+/* 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)
 {
        bcsr->intclr_mask = 1 << (irq_nr - PB1200_INT_BEGIN);
        bcsr->intclr = 1 << (irq_nr - PB1200_INT_BEGIN);
+       au_sync();
 }
 
-static unsigned int pb1200_setup_cascade(void)
-{
-       return request_irq(AU1000_GPIO_7, &pb1200_cascade_handler,
-                          0, "Pb1200 Cascade", &pb1200_cascade_handler);
-}
-
-static unsigned int pb1200_startup_irq(unsigned int irq)
+static void pb1200_maskack_irq(unsigned int irq_nr)
 {
-       if (++pb1200_cascade_en == 1) {
-               int res;
-
-               res = pb1200_setup_cascade();
-               if (res)
-                       return res;
-       }
-
-       pb1200_enable_irq(irq);
-
-       return 0;
+       bcsr->intclr_mask = 1 << (irq_nr - PB1200_INT_BEGIN);
+       bcsr->intclr = 1 << (irq_nr - PB1200_INT_BEGIN);
+       bcsr->int_status = 1 << (irq_nr - PB1200_INT_BEGIN);    /* ack */
+       au_sync();
 }
 
-static void pb1200_shutdown_irq(unsigned int irq)
+static void pb1200_unmask_irq(unsigned int irq_nr)
 {
-       pb1200_disable_irq(irq);
-       if (--pb1200_cascade_en == 0)
-               free_irq(AU1000_GPIO_7, &pb1200_cascade_handler);
+       bcsr->intset = 1 << (irq_nr - PB1200_INT_BEGIN);
+       bcsr->intset_mask = 1 << (irq_nr - PB1200_INT_BEGIN);
+       au_sync();
 }
 
-static struct irq_chip external_irq_type = {
+static struct irq_chip pb1200_cpld_irq_type = {
 #ifdef CONFIG_MIPS_PB1200
        .name = "Pb1200 Ext",
 #endif
 #ifdef CONFIG_MIPS_DB1200
        .name = "Db1200 Ext",
 #endif
-       .startup  = pb1200_startup_irq,
-       .shutdown = pb1200_shutdown_irq,
-       .ack      = pb1200_disable_irq,
-       .mask     = pb1200_disable_irq,
-       .mask_ack = pb1200_disable_irq,
-       .unmask   = pb1200_enable_irq,
+       .mask           = pb1200_mask_irq,
+       .mask_ack       = pb1200_maskack_irq,
+       .unmask         = pb1200_unmask_irq,
 };
 
 void __init board_init_irq(void)
@@ -147,15 +120,15 @@ void __init board_init_irq(void)
                panic("Game over.  Your score is 0.");
        }
 #endif
+       /* mask & disable & ack all */
+       bcsr->intclr_mask = 0xffff;
+       bcsr->intclr = 0xffff;
+       bcsr->int_status = 0xffff;
+       au_sync();
 
-       for (irq = PB1200_INT_BEGIN; irq <= PB1200_INT_END; irq++) {
-               set_irq_chip_and_handler(irq, &external_irq_type,
-                                        handle_level_irq);
-               pb1200_disable_irq(irq);
-       }
+       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");
 
-       /*
-        * GPIO_7 can not be hooked here, so it is hooked upon first
-        * request of any source attached to the cascade.
-        */
+       set_irq_chained_handler(AU1000_GPIO_7, pb1200_cascade_handler);
 }