openwrt/target/linux/brcm2708/patches-4.1/0054-bcm2709-Simplify-and-strip-down-IRQ-handler.patch

From 39a6ff9b1ecb74c734606429647a9d783c7504f1 Mon Sep 17 00:00:00 2001
From: popcornmix <popcornmix@gmail.com>
Date: Fri, 20 Jun 2014 17:19:27 +0100
Subject: [PATCH 054/148] bcm2709: Simplify and strip down IRQ handler

---
 arch/arm/include/asm/entry-macro-multi.S         |   2 +
 arch/arm/mach-bcm2709/include/mach/entry-macro.S | 173 +++++++++++------------
 2 files changed, 87 insertions(+), 88 deletions(-)

--- a/arch/arm/include/asm/entry-macro-multi.S
+++ b/arch/arm/include/asm/entry-macro-multi.S
@@ -1,5 +1,6 @@
 #include <asm/assembler.h>
 
+#ifndef CONFIG_ARCH_BCM2709
 /*
  * Interrupt handling.  Preserves r7, r8, r9
  */
@@ -28,6 +29,7 @@
 #endif
 9997:
 	.endm
+#endif
 
 	.macro	arch_irq_handler, symbol_name
 	.align	5
--- a/arch/arm/mach-bcm2709/include/mach/entry-macro.S
+++ b/arch/arm/mach-bcm2709/include/mach/entry-macro.S
@@ -22,102 +22,99 @@
 #include <mach/hardware.h>
 #include <mach/irqs.h>
 
-		.macro	disable_fiq
-		.endm
+	.macro  arch_ret_to_user, tmp1, tmp2
+	.endm
 
-		.macro  get_irqnr_preamble, base, tmp
-		ldr	\base, =IO_ADDRESS(ARMCTRL_IC_BASE)
-		.endm
-
-		.macro  arch_ret_to_user, tmp1, tmp2
-		.endm
-
-		.macro	get_irqnr_and_base, irqnr, irqstat, base, tmp
-		/* get core number */
-		mrc     p15, 0, \tmp, c0, c0, 5
-		ubfx    \tmp, \tmp, #0, #2
-
-		/* get core's local interrupt controller */
-		ldr	\irqstat, = __io_address(ARM_LOCAL_IRQ_PENDING0)	@ local interrupt source
-		add	\irqstat, \irqstat, \tmp, lsl #2
-		ldr	\tmp, [\irqstat]
-		/* ignore gpu interrupt */
-		bic     \tmp, #0x100
-		/* ignore mailbox interrupts */
-		bics    \tmp, #0xf0
-		beq	1005f
-
-		@ For non-zero x, LSB(x) = 31 - CLZ(x^(x-1))
-		@ N.B. CLZ is an ARM5 instruction.
-		mov	\irqnr, #(ARM_IRQ_LOCAL_BASE + 31)
-		sub	\irqstat, \tmp, #1
-		eor	\irqstat, \irqstat, \tmp
-		clz	\tmp, \irqstat
-		sub	\irqnr, \tmp
-		b	1020f
-1005:
-		/* get core number */
-		mrc     p15, 0, \tmp, c0, c0, 5
-		ubfx    \tmp, \tmp, #0, #2
-
-                cmp	\tmp, #1
-		beq	1020f
-                cmp	\tmp, #2
-		beq	1020f
-                cmp	\tmp, #3
-		beq	1020f
-
-		/* get masked status */
-		ldr	\irqstat, [\base, #(ARM_IRQ_PEND0 - ARMCTRL_IC_BASE)]
-		mov	\irqnr, #(ARM_IRQ0_BASE + 31)
-		and	\tmp, \irqstat, #0x300		 @ save bits 8 and 9
-		/* clear bits 8 and 9, and test */
-		bics	\irqstat, \irqstat, #0x300
-		bne	1010f
-
-		tst	\tmp, #0x100
-		ldrne	\irqstat, [\base, #(ARM_IRQ_PEND1 - ARMCTRL_IC_BASE)]
-		movne \irqnr, #(ARM_IRQ1_BASE + 31)
-		@ Mask out the interrupts also present in PEND0 - see SW-5809
-		bicne \irqstat, #((1<<7) | (1<<9) | (1<<10))
-		bicne \irqstat, #((1<<18) | (1<<19))
-		bne	1010f
-
-		tst	\tmp, #0x200
-		ldrne \irqstat, [\base, #(ARM_IRQ_PEND2 - ARMCTRL_IC_BASE)]
-		movne \irqnr, #(ARM_IRQ2_BASE + 31)
-		@ Mask out the interrupts also present in PEND0 - see SW-5809
-		bicne \irqstat, #((1<<21) | (1<<22) | (1<<23) | (1<<24) | (1<<25))
-		bicne \irqstat, #((1<<30))
-		beq 1020f
+	.macro	get_irqnr_and_base, irqnr, irqstat, base, tmp
 
+	/* get core number */
+	mrc     p15, 0, \base, c0, c0, 5
+	ubfx    \base, \base, #0, #2
+
+	/* get core's local interrupt controller */
+	ldr	\irqstat, = __io_address(ARM_LOCAL_IRQ_PENDING0)	@ local interrupt source
+	add	\irqstat, \irqstat, \base, lsl #2
+	ldr	\tmp, [\irqstat]
+#ifdef CONFIG_SMP
+	/* test for mailbox0 (IPI) interrupt */
+	tst	\tmp, #0x10
+	beq	1030f
+
+	/* get core's mailbox interrupt control */
+	ldr	\irqstat, = __io_address(ARM_LOCAL_MAILBOX0_CLR0)	@ mbox_clr
+	add	\irqstat, \irqstat, \base, lsl #4
+	ldr	\tmp, [\irqstat]
+	clz	\tmp, \tmp
+	rsb	\irqnr, \tmp, #31
+	mov	\tmp, #1
+	lsl	\tmp, \irqnr
+	str	\tmp, [\irqstat]  @ clear interrupt source
+	dsb
+	mov	r1, sp
+	adr	lr, BSYM(1b)
+	b	do_IPI
+#endif
+1030:
+	/* check gpu interrupt */
+	tst	\tmp, #0x100
+	beq	1040f
+
+	ldr	\base, =IO_ADDRESS(ARMCTRL_IC_BASE)
+	/* get masked status */
+	ldr	\irqstat, [\base, #(ARM_IRQ_PEND0 - ARMCTRL_IC_BASE)]
+	mov	\irqnr, #(ARM_IRQ0_BASE + 31)
+	and	\tmp, \irqstat, #0x300		 @ save bits 8 and 9
+	/* clear bits 8 and 9, and test */
+	bics	\irqstat, \irqstat, #0x300
+	bne	1010f
+
+	tst	\tmp, #0x100
+	ldrne	\irqstat, [\base, #(ARM_IRQ_PEND1 - ARMCTRL_IC_BASE)]
+	movne	\irqnr, #(ARM_IRQ1_BASE + 31)
+	@ Mask out the interrupts also present in PEND0 - see SW-5809
+	bicne	\irqstat, #((1<<7) | (1<<9) | (1<<10))
+	bicne	\irqstat, #((1<<18) | (1<<19))
+	bne	1010f
+
+	tst	\tmp, #0x200
+	ldrne	\irqstat, [\base, #(ARM_IRQ_PEND2 - ARMCTRL_IC_BASE)]
+	movne	\irqnr, #(ARM_IRQ2_BASE + 31)
+	@ Mask out the interrupts also present in PEND0 - see SW-5809
+	bicne	\irqstat, #((1<<21) | (1<<22) | (1<<23) | (1<<24) | (1<<25))
+	bicne	\irqstat, #((1<<30))
+	beq	1020f
 1010:
-		@ For non-zero x, LSB(x) = 31 - CLZ(x^(x-1))
-		@ N.B. CLZ is an ARM5 instruction.
-		sub	\tmp, \irqstat, #1
-		eor	\irqstat, \irqstat, \tmp
-		clz	\tmp, \irqstat
-		sub	\irqnr, \tmp
+	@ For non-zero x, LSB(x) = 31 - CLZ(x^(x-1))
+	sub	\tmp, \irqstat, #1
+	eor	\irqstat, \irqstat, \tmp
+	clz	\tmp, \irqstat
+	sub	\irqnr, \tmp
+	b	1050f
+1040:
+	cmp	\tmp, #0
+	beq	1020f
+
+	/* handle local (e.g. timer) interrupts */
+	@ For non-zero x, LSB(x) = 31 - CLZ(x^(x-1))
+	mov	\irqnr, #(ARM_IRQ_LOCAL_BASE + 31)
+	sub	\irqstat, \tmp, #1
+	eor	\irqstat, \irqstat, \tmp
+	clz	\tmp, \irqstat
+	sub	\irqnr, \tmp
+1050:
+	mov	r1, sp
+	@
+	@ routine called with r0 = irq number, r1 = struct pt_regs *
+	@
+	adr	lr, BSYM(1b)
+	b	asm_do_IRQ
 
 1020:	@ EQ will be set if no irqs pending
+	.endm
 
-		.endm
-
-		.macro  test_for_ipi, irqnr, irqstat, base, tmp
-		/* get core number */
-		mrc     p15, 0, \tmp, c0, c0, 5
-		ubfx    \tmp, \tmp, #0, #2
-		/* get core's mailbox interrupt control */
-		ldr	\irqstat, = __io_address(ARM_LOCAL_MAILBOX0_CLR0)	@ mbox_clr
-		add	\irqstat, \irqstat, \tmp, lsl #4
-		ldr	\tmp, [\irqstat]
-		cmp     \tmp, #0
-		beq	1030f
-		clz	\tmp, \tmp
-		rsb	\irqnr, \tmp, #31
-		mov	\tmp, #1
-		lsl	\tmp, \irqnr
-		str	\tmp, [\irqstat]  @ clear interrupt source
-		dsb
-1030:	@ EQ will be set if no irqs pending
-		.endm
+/*
+ * Interrupt handling.  Preserves r7, r8, r9
+ */
+	.macro	arch_irq_handler_default
+1:	get_irqnr_and_base r0, r2, r6, lr
+	.endm