From e4ac58afdfac792c0583af30dbd9eae53e24c78b Mon Sep 17 00:00:00 2001 From: Ralf Baechle Date: Mon, 3 Apr 2006 17:56:36 +0100 Subject: [MIPS] Rewrite all the assembler interrupt handlers to C. Saves like 1,600 lines of code, is way easier to debug, compilers frequently do a better job than the cut and paste type of handlers many boards had. And finally having all the stuff done in a single place also means alot of bug potencial for the MT ASE is gone. The only surviving handler in assembler is the DECstation one; I hope Maciej will rewrite it. Signed-off-by: Ralf Baechle --- arch/mips/mips-boards/malta/Makefile | 2 +- arch/mips/mips-boards/malta/malta-irq.S | 122 -------------------------------- arch/mips/mips-boards/malta/malta_int.c | 91 ++++++++++++++++++++++-- 3 files changed, 88 insertions(+), 127 deletions(-) delete mode 100644 arch/mips/mips-boards/malta/malta-irq.S (limited to 'arch/mips/mips-boards/malta') diff --git a/arch/mips/mips-boards/malta/Makefile b/arch/mips/mips-boards/malta/Makefile index 3ae8fe6c007..fd4c143c0e2 100644 --- a/arch/mips/mips-boards/malta/Makefile +++ b/arch/mips/mips-boards/malta/Makefile @@ -19,4 +19,4 @@ # under Linux. # -obj-y := malta_int.o malta-irq.o malta_setup.o +obj-y := malta_int.o malta_setup.o diff --git a/arch/mips/mips-boards/malta/malta-irq.S b/arch/mips/mips-boards/malta/malta-irq.S deleted file mode 100644 index 6217aff3be0..00000000000 --- a/arch/mips/mips-boards/malta/malta-irq.S +++ /dev/null @@ -1,122 +0,0 @@ -/* - * Carsten Langgaard, carstenl@mips.com - * Copyright (C) 1999, 2000 MIPS Technologies, Inc. All rights reserved. - * - * ######################################################################## - * - * This program is free software; you can distribute it and/or modify it - * under the terms of the GNU General Public License (Version 2) as - * published by the Free Software Foundation. - * - * This program is distributed in the hope it will be useful, but WITHOUT - * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or - * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License - * for more details. - * - * You should have received a copy of the GNU General Public License along - * with this program; if not, write to the Free Software Foundation, Inc., - * 59 Temple Place - Suite 330, Boston MA 02111-1307, USA. - * - * ######################################################################## - * - * Interrupt exception dispatch code. - * - */ -#include - -#include -#include -#include -#include -#include - -/* - * IRQs on the Malta 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. - */ - - .text - .set noreorder - .set noat - .align 5 - NESTED(mipsIRQ, PT_SIZE, sp) - SAVE_ALL - CLI - .set at - - mfc0 s0, CP0_CAUSE # get irq bits - mfc0 s1, CP0_STATUS # get irq mask - andi s0, ST0_IM # CAUSE.CE may be non-zero! - and s0, s1 - -#if defined(CONFIG_CPU_MIPS32) || defined(CONFIG_CPU_MIPS64) - .set mips32 - clz a0, s0 - .set mips0 - negu a0 - addu a0, 31-CAUSEB_IP - bltz a0, spurious -#else - beqz s0, spurious - li a0, 7 - - and t0, s0, 0xf000 - sltiu t0, t0, 1 - sll t0, 2 - subu a0, t0 - sll s0, t0 - - and t0, s0, 0xc000 - sltiu t0, t0, 1 - sll t0, 1 - subu a0, t0 - sll s0, t0 - - and t0, s0, 0x8000 - sltiu t0, t0, 1 - # sll t0, 0 - subu a0, t0 - # sll s0, t0 -#endif - - li a1, MIPSCPU_INT_I8259A - bne a0, a1, 1f - addu a0, MIPSCPU_INT_BASE - - jal malta_hw0_irqdispatch - move a0, sp - - j ret_from_irq - nop -1: - - jal do_IRQ - move a1, sp - - j ret_from_irq - nop - -spurious: - j spurious_interrupt - nop - END(mipsIRQ) diff --git a/arch/mips/mips-boards/malta/malta_int.c b/arch/mips/mips-boards/malta/malta_int.c index d06dc5ad6c9..1da8c18b9c8 100644 --- a/arch/mips/mips-boards/malta/malta_int.c +++ b/arch/mips/mips-boards/malta/malta_int.c @@ -40,7 +40,6 @@ #include #include -extern asmlinkage void mipsIRQ(void); extern void mips_timer_interrupt(void); static DEFINE_SPINLOCK(mips_irq_lock); @@ -114,7 +113,7 @@ static inline int get_int(void) return irq; } -void malta_hw0_irqdispatch(struct pt_regs *regs) +static void malta_hw0_irqdispatch(struct pt_regs *regs) { int irq; @@ -182,6 +181,92 @@ void corehi_irqdispatch(struct pt_regs *regs) die("CoreHi interrupt", 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 Malta 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_I8259A) + malta_hw0_irqdispatch(regs); + else if (irq > 0) + do_IRQ(MIPSCPU_INT_BASE + irq, regs); + else + spurious_interrupt(regs); +} + static struct irqaction i8259irq = { .handler = no_action, .name = "XT-PIC cascade" @@ -214,7 +299,6 @@ int __initdata msc_nr_eicirqs = sizeof(msc_eicirqmap)/sizeof(msc_irqmap_t); void __init arch_init_irq(void) { - set_except_vector(0, mipsIRQ); init_i8259_irqs(); if (!cpu_has_veic) @@ -245,7 +329,6 @@ void __init arch_init_irq(void) setup_irq (MIPSCPU_INT_BASE+MIPSCPU_INT_COREHI, &corehi_irqaction); } else { - set_except_vector(0, mipsIRQ); setup_irq (MIPSCPU_INT_BASE+MIPSCPU_INT_I8259A, &i8259irq); setup_irq (MIPSCPU_INT_BASE+MIPSCPU_INT_COREHI, &corehi_irqaction); } -- cgit v1.2.3