[ARM PATCH] 2259/1: Rip out ixp2000 IRQ_ERR_STATUS demultiplexing

Patch from Lennert Buytenhek
  
There are thirteen different IRQs chained off IRQ_ERR_STATUS, one for
each possible error class that the IXP can signal an interrupt for, but
there are no in-tree users of these interrupts, and it doesn't make much
sense to treat them as separate interrupts if we can just have one
handler checking each of the thirteen errors in one go instead.
  
Besides that, the error interrupt handling can't even have been working
properly in the first place as the chained handler was testing the wrong
bits in the IRQ_ERR_STATUS register.
  
So this patch rips it all out.
  

Signed-off-by: Lennert Buytenhek
Signed-off-by: Deepak Saxena
Signed-off-by: Russell King

arch/arm/mach-ixp2000/core.c

@@ -309,41 +309,6 @@ static struct irqchip ixp2000_pci_irq_chip = {
 	.unmask	= ixp2000_pci_irq_unmask
 };
 
-/*
- * Error interrupts. These are used extensively by the microengine drivers
- */
-static void ixp2000_err_irq_handler(unsigned int irq, struct irqdesc *desc,  struct pt_regs *regs)
-{
-	int i;
-	unsigned long status = *IXP2000_IRQ_ERR_STATUS;
-
-
-	for (i = 0; i <= 12; i++) {
-		if (status & (1 << i)) {
-			desc = irq_desc + IRQ_IXP2000_DRAM0_MIN_ERR + i;
-			desc->handle(IRQ_IXP2000_DRAM0_MIN_ERR + i, desc, regs);
-		}
-	}
-}
-
-static void ixp2000_err_irq_mask(unsigned int irq)
-{
-	ixp2000_reg_write(IXP2000_IRQ_ERR_ENABLE_CLR,
-			(1 << (irq - IRQ_IXP2000_DRAM0_MIN_ERR)));
-}
-
-static void ixp2000_err_irq_unmask(unsigned int irq)
-{
-	ixp2000_reg_write(IXP2000_IRQ_ERR_ENABLE_SET,
-			(1 << (irq - IRQ_IXP2000_DRAM0_MIN_ERR)));
-}
-
-static struct irqchip ixp2000_err_irq_chip = {
-	.ack	= ixp2000_err_irq_mask,
-	.mask	= ixp2000_err_irq_mask,
-	.unmask	= ixp2000_err_irq_unmask
-};
-
 static void ixp2000_irq_mask(unsigned int irq)
 {
 	ixp2000_reg_write(IXP2000_IRQ_ENABLE_CLR, (1 << irq));
@@ -415,12 +380,5 @@ void __init ixp2000_init_irq(void)
 		set_irq_handler(irq, do_level_IRQ);
 		set_irq_flags(irq, IRQF_VALID);
 	}
-
-	for (irq = IRQ_IXP2000_DRAM0_MIN_ERR; irq <= IRQ_IXP2000_SP_INT; irq++) {
-		set_irq_chip(irq, &ixp2000_err_irq_chip);
-		set_irq_handler(irq, do_level_IRQ);
-		set_irq_flags(irq, IRQF_VALID);
-	}       
-	set_irq_chained_handler(IRQ_IXP2000_ERRSUM, ixp2000_err_irq_handler);
 }
 

include/asm-arm/arch-ixp2000/irqs.h

@@ -67,22 +67,7 @@
 #define IRQ_IXP2000_PCIA		40
 #define IRQ_IXP2000_PCIB		41
 
-/* Int sources from IRQ_ERROR_STATUS */
-#define IRQ_IXP2000_DRAM0_MIN_ERR	42
-#define IRQ_IXP2000_DRAM0_MAJ_ERR	43
-#define IRQ_IXP2000_DRAM1_MIN_ERR	44
-#define IRQ_IXP2000_DRAM1_MAJ_ERR	45
-#define IRQ_IXP2000_DRAM2_MIN_ERR	46
-#define IRQ_IXP2000_DRAM2_MAJ_ERR	47
-#define IRQ_IXP2000_SRAM0_ERR		48
-#define IRQ_IXP2000_SRAM1_ERR		49
-#define IRQ_IXP2000_SRAM2_ERR           50
-#define IRQ_IXP2000_SRAM3_ERR		51
-#define IRQ_IXP2000_MEDIA_ERR		52
-#define IRQ_IXP2000_PCI_ERR		53
-#define IRQ_IXP2000_SP_INT		54
-
-#define NR_IXP2000_IRQS                 55
+#define NR_IXP2000_IRQS                 42
 
 #define	IXP2000_BOARD_IRQ(x)		(NR_IXP2000_IRQS + (x))