Merge branch 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus

* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus: (47 commits)
  [MAINTAINERS] The ham radio code now has website at http://www.linux-ax25.org.
  [MIPS] Use __ffs() instead of ffs() for waybit calculation.
  [MIPS] Fix Makefile bugs for MIPS32/MIPS64 R1 and R2.
  [MIPS] Handle IDE PIO cache aliases on SMP.
  [MIPS] Make mips_srs_init static.
  [MIPS] MIPS boards: Set HZ to 100.
  [MIPS] kgdb: Let gcc compute the array size itself.
  [MIPS] FPU affinity for MT ASE.
  [MIPS] MT: Improved multithreading support.
  [MIPS] kpsd and other AP/SP improvements.
  [MIPS] R2: Instruction hazard barrier.
  [MIPS] Fix genrtc compilation.
  [MIPS] R2: Implement shadow register allocation without spinlock.
  [MIPS] Fix VR41xx build errors.
  [MIPS] Fix tx49_blast_icache32_page_indexed.
  [MIPS] Enable SCHED_NO_NO_OMIT_FRAME_POINTER for MIPS.
  [MIPS] Use "R" constraint for cache_op.
  [MIPS] Rewrite all the assembler interrupt handlers to C.
  [MIPS] Fix the crime against humanity that mipsIRQ.S is.
  [MIPS] Fixup damage done by 22a9835c350782a5c3257343713932af3ac92ee0.
  ...

1 files changed, 86 insertions, 6 deletions

diff --git a/arch/mips/mips-boards/atlas/atlas_int.c b/arch/mips/mips-boards/atlas/atlas_int.c
index bc0ebc69bfb3..db53950b7cfb 100644
--- a/arch/mips/mips-boards/atlas/atlas_int.c
+++ b/arch/mips/mips-boards/atlas/atlas_int.c
@@ -39,8 +39,6 @@
 
 static struct atlas_ictrl_regs *atlas_hw0_icregs;
 
-extern asmlinkage void mipsIRQ(void);
-
 #if 0
 #define DEBUG_INT(x...) printk(x)
 #else
@@ -98,7 +96,7 @@ static inline int ls1bit32(unsigned int x)
 	return b;
 }
 
-void atlas_hw0_irqdispatch(struct pt_regs *regs)
+static inline void atlas_hw0_irqdispatch(struct pt_regs *regs)
 {
 	unsigned long int_status;
 	int irq;
@@ -116,6 +114,91 @@ void atlas_hw0_irqdispatch(struct pt_regs *regs)
 	do_IRQ(irq, regs);
 }
 
+static inline int clz(unsigned long x)
+{
+	__asm__ (
+	"	.set	push					\n"
+	"	.set	mips32					\n"
+	"	clz	%0, %1					\n"
+	"	.set	pop					\n"
+	: "=r" (x)
+	: "r" (x));
+
+	return x;
+}
+
+/*
+ * Version of ffs that only looks at bits 12..15.
+ */
+static inline unsigned int irq_ffs(unsigned int pending)
+{
+#if defined(CONFIG_CPU_MIPS32) || defined(CONFIG_CPU_MIPS64)
+	return -clz(pending) + 31 - CAUSEB_IP;
+#else
+	unsigned int a0 = 7;
+	unsigned int t0;
+
+	t0 = s0 & 0xf000;
+	t0 = t0 < 1;
+	t0 = t0 << 2;
+	a0 = a0 - t0;
+	s0 = s0 << t0;
+
+	t0 = s0 & 0xc000;
+	t0 = t0 < 1;
+	t0 = t0 << 1;
+	a0 = a0 - t0;
+	s0 = s0 << t0;
+
+	t0 = s0 & 0x8000;
+	t0 = t0 < 1;
+	//t0 = t0 << 2;
+	a0 = a0 - t0;
+	//s0 = s0 << t0;
+
+	return a0;
+#endif
+}
+
+/*
+ * IRQs on the Atlas board look basically (barring software IRQs which we
+ * don't use at all and all external interrupt sources are combined together
+ * on hardware interrupt 0 (MIPS IRQ 2)) like:
+ *
+ *	MIPS IRQ	Source
+ *      --------        ------
+ *             0	Software (ignored)
+ *             1        Software (ignored)
+ *             2        Combined hardware interrupt (hw0)
+ *             3        Hardware (ignored)
+ *             4        Hardware (ignored)
+ *             5        Hardware (ignored)
+ *             6        Hardware (ignored)
+ *             7        R4k timer (what we use)
+ *
+ * We handle the IRQ according to _our_ priority which is:
+ *
+ * Highest ----     R4k Timer
+ * Lowest  ----     Combined hardware interrupt
+ *
+ * then we just return, if multiple IRQs are pending then we will just take
+ * another exception, big deal.
+ */
+asmlinkage void plat_irq_dispatch(struct pt_regs *regs)
+{
+	unsigned int pending = read_c0_cause() & read_c0_status() & ST0_IM;
+	int irq;
+
+	irq = irq_ffs(pending);
+
+	if (irq == MIPSCPU_INT_ATLAS)
+		atlas_hw0_irqdispatch(regs);
+	else if (irq > 0)
+		do_IRQ(MIPSCPU_INT_BASE + irq, regs);
+	else
+		spurious_interrupt(regs);
+}
+
 void __init arch_init_irq(void)
 {
 	int i;
@@ -128,9 +211,6 @@ void __init arch_init_irq(void)
 	 */
 	atlas_hw0_icregs->intrsten = 0xffffffff;
 
-	/* Now safe to set the exception vector. */
-	set_except_vector(0, mipsIRQ);
-
 	for (i = ATLASINT_BASE; i <= ATLASINT_END; i++) {
 		irq_desc[i].status	= IRQ_DISABLED;
 		irq_desc[i].action	= 0;