[PATCH] FRV: improve FRV's use of generic IRQ handling

Improve FRV's use of generic IRQ handling:

 (*) Use generic_handle_irq() rather than __do_IRQ() as the latter is obsolete.

 (*) Don't implement enable() and disable() ops as these will fall back to
     using unmask() and mask().

 (*) Provide mask_ack() functions to avoid a call each to mask() and ack().

 (*) Make the cascade handlers always return IRQ_HANDLED.

 (*) Implement the mask() and unmask() functions in the same order as they're
     listed in the ops table.

Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

arch/frv/kernel/irq-mb93091.c

@@ -36,41 +36,45 @@
 /*
  * on-motherboard FPGA PIC operations
  */
-static void frv_fpga_enable(unsigned int irq)
+static void frv_fpga_mask(unsigned int irq)
 {
 	uint16_t imr = __get_IMR();
 
-	imr &= ~(1 << (irq - IRQ_BASE_FPGA));
+	imr |= 1 << (irq - IRQ_BASE_FPGA);
 
 	__set_IMR(imr);
 }
 
-static void frv_fpga_disable(unsigned int irq)
+static void frv_fpga_ack(unsigned int irq)
+{
+	__clr_IFR(1 << (irq - IRQ_BASE_FPGA));
+}
+
+static void frv_fpga_mask_ack(unsigned int irq)
 {
 	uint16_t imr = __get_IMR();
 
 	imr |= 1 << (irq - IRQ_BASE_FPGA);
-
 	__set_IMR(imr);
-}
 
-static void frv_fpga_ack(unsigned int irq)
-{
 	__clr_IFR(1 << (irq - IRQ_BASE_FPGA));
 }
 
-static void frv_fpga_end(unsigned int irq)
+static void frv_fpga_unmask(unsigned int irq)
 {
+	uint16_t imr = __get_IMR();
+
+	imr &= ~(1 << (irq - IRQ_BASE_FPGA));
+
+	__set_IMR(imr);
 }
 
 static struct irq_chip frv_fpga_pic = {
 	.name		= "mb93091",
-	.enable		= frv_fpga_enable,
-	.disable	= frv_fpga_disable,
 	.ack		= frv_fpga_ack,
-	.mask		= frv_fpga_disable,
-	.unmask		= frv_fpga_enable,
-	.end		= frv_fpga_end,
+	.mask		= frv_fpga_mask,
+	.mask_ack	= frv_fpga_mask_ack,
+	.unmask		= frv_fpga_unmask,
 };
 
 /*
@@ -79,7 +83,6 @@ static struct irq_chip frv_fpga_pic = {
 static irqreturn_t fpga_interrupt(int irq, void *_mask, struct pt_regs *regs)
 {
 	uint16_t imr, mask = (unsigned long) _mask;
-	irqreturn_t iret = 0;
 
 	imr = __get_IMR();
 	mask = mask & ~imr & __get_IFR();
@@ -92,11 +95,10 @@ static irqreturn_t fpga_interrupt(int irq, void *_mask, struct pt_regs *regs)
 		irq = 31 - irq;
 		mask &= ~(1 << irq);
 
-		if (__do_IRQ(IRQ_BASE_FPGA + irq, regs))
-			iret |= IRQ_HANDLED;
+		generic_handle_irq(IRQ_BASE_FPGA + irq, regs);
 	}
 
-	return iret;
+	return IRQ_HANDLED;
 }
 
 /*

arch/frv/kernel/irq-mb93093.c

@@ -35,40 +35,44 @@
 /*
  * off-CPU FPGA PIC operations
  */
-static void frv_fpga_enable(unsigned int irq)
+static void frv_fpga_mask(unsigned int irq)
 {
 	uint16_t imr = __get_IMR();
 
-	imr &= ~(1 << (irq - IRQ_BASE_FPGA));
-
+	imr |= 1 << (irq - IRQ_BASE_FPGA);
 	__set_IMR(imr);
 }
 
-static void frv_fpga_disable(unsigned int irq)
+static void frv_fpga_ack(unsigned int irq)
+{
+	__clr_IFR(1 << (irq - IRQ_BASE_FPGA));
+}
+
+static void frv_fpga_mask_ack(unsigned int irq)
 {
 	uint16_t imr = __get_IMR();
 
 	imr |= 1 << (irq - IRQ_BASE_FPGA);
-
 	__set_IMR(imr);
-}
 
-static void frv_fpga_ack(unsigned int irq)
-{
 	__clr_IFR(1 << (irq - IRQ_BASE_FPGA));
 }
 
-static void frv_fpga_end(unsigned int irq)
+static void frv_fpga_unmask(unsigned int irq)
 {
+	uint16_t imr = __get_IMR();
+
+	imr &= ~(1 << (irq - IRQ_BASE_FPGA));
+
+	__set_IMR(imr);
 }
 
 static struct irq_chip frv_fpga_pic = {
 	.name		= "mb93093",
-	.enable		= frv_fpga_enable,
-	.disable	= frv_fpga_disable,
 	.ack		= frv_fpga_ack,
-	.mask		= frv_fpga_disable,
-	.unmask		= frv_fpga_enable,
+	.mask		= frv_fpga_mask,
+	.mask_ack	= frv_fpga_mask_ack,
+	.unmask		= frv_fpga_unmask,
 	.end		= frv_fpga_end,
 };
 
@@ -78,7 +82,6 @@ static struct irq_chip frv_fpga_pic = {
 static irqreturn_t fpga_interrupt(int irq, void *_mask, struct pt_regs *regs)
 {
 	uint16_t imr, mask = (unsigned long) _mask;
-	irqreturn_t iret = 0;
 
 	imr = __get_IMR();
 	mask = mask & ~imr & __get_IFR();
@@ -91,11 +94,10 @@ static irqreturn_t fpga_interrupt(int irq, void *_mask, struct pt_regs *regs)
 		irq = 31 - irq;
 		mask &= ~(1 << irq);
 
-		if (__do_IRQ(IRQ_BASE_FPGA + irq, regs))
-			iret |= IRQ_HANDLED;
+		generic_irq_handle(IRQ_BASE_FPGA + irq, regs);
 	}
 
-	return iret;
+	return IRQ_HANDLED;
 }
 
 /*

arch/frv/kernel/irq-mb93493.c

@@ -43,8 +43,9 @@
 
 /*
  * daughter board PIC operations
+ * - there is no way to ACK interrupts in the MB93493 chip
  */
-static void frv_mb93493_enable(unsigned int irq)
+static void frv_mb93493_mask(unsigned int irq)
 {
 	uint32_t iqsr;
 	volatile void *piqsr;
@@ -55,11 +56,15 @@ static void frv_mb93493_enable(unsigned int irq)
 		piqsr = __addr_MB93493_IQSR(0);
 
 	iqsr = readl(piqsr);
-	iqsr |= 1 << (irq - IRQ_BASE_MB93493 + 16);
+	iqsr &= ~(1 << (irq - IRQ_BASE_MB93493 + 16));
 	writel(iqsr, piqsr);
 }
 
-static void frv_mb93493_disable(unsigned int irq)
+static void frv_mb93493_ack(unsigned int irq)
+{
+}
+
+static void frv_mb93493_unmask(unsigned int irq)
 {
 	uint32_t iqsr;
 	volatile void *piqsr;
@@ -70,26 +75,16 @@ static void frv_mb93493_disable(unsigned int irq)
 		piqsr = __addr_MB93493_IQSR(0);
 
 	iqsr = readl(piqsr);
-	iqsr &= ~(1 << (irq - IRQ_BASE_MB93493 + 16));
+	iqsr |= 1 << (irq - IRQ_BASE_MB93493 + 16);
 	writel(iqsr, piqsr);
 }
 
-static void frv_mb93493_ack(unsigned int irq)
-{
-}
-
-static void frv_mb93493_end(unsigned int irq)
-{
-}
-
 static struct irq_chip frv_mb93493_pic = {
 	.name		= "mb93093",
-	.enable		= frv_mb93493_enable,
-	.disable	= frv_mb93493_disable,
 	.ack		= frv_mb93493_ack,
-	.mask		= frv_mb93493_disable,
-	.unmask		= frv_mb93493_enable,
-	.end		= frv_mb93493_end,
+	.mask		= frv_mb93493_mask,
+	.mask_ack	= frv_mb93493_mask,
+	.unmask		= frv_mb93493_unmask,
 };
 
 /*
@@ -98,7 +93,6 @@ static struct irq_chip frv_mb93493_pic = {
 static irqreturn_t mb93493_interrupt(int irq, void *_piqsr, struct pt_regs *regs)
 {
 	volatile void *piqsr = _piqsr;
-	irqreturn_t iret = 0;
 	uint32_t iqsr;
 
 	iqsr = readl(piqsr);
@@ -112,11 +106,10 @@ static irqreturn_t mb93493_interrupt(int irq, void *_piqsr, struct pt_regs *regs
 		irq = 31 - irq;
 		iqsr &= ~(1 << irq);
 
-		if (__do_IRQ(IRQ_BASE_MB93493 + irq, regs))
-			iret |= IRQ_HANDLED;
+		generic_handle_irq(IRQ_BASE_MB93493 + irq, regs);
 	}
 
-	return iret;
+	return IRQ_HANDLED;
 }
 
 /*

arch/frv/kernel/irq.c

@@ -97,19 +97,8 @@ int show_interrupts(struct seq_file *p, void *v)
 /*
  * on-CPU PIC operations
  */
-static void frv_cpupic_enable(unsigned int irqlevel)
-{
-	__clr_MASK(irqlevel);
-}
-
-static void frv_cpupic_disable(unsigned int irqlevel)
-{
-	__set_MASK(irqlevel);
-}
-
 static void frv_cpupic_ack(unsigned int irqlevel)
 {
-	__set_MASK(irqlevel);
 	__clr_RC(irqlevel);
 	__clr_IRL();
 }
@@ -138,8 +127,6 @@ static void frv_cpupic_end(unsigned int irqlevel)
 
 static struct irq_chip frv_cpu_pic = {
 	.name		= "cpu",
-	.enable		= frv_cpupic_enable,
-	.disable	= frv_cpupic_disable,
 	.ack		= frv_cpupic_ack,
 	.mask		= frv_cpupic_mask,
 	.mask_ack	= frv_cpupic_mask_ack,
@@ -156,7 +143,7 @@ static struct irq_chip frv_cpu_pic = {
 asmlinkage void do_IRQ(void)
 {
 	irq_enter();
-	__do_IRQ(__get_IRL(), __frame);
+	generic_handle_irq(__get_IRL(), __frame);
 	irq_exit();
 }