From 02416dcf5a94af34bcd28b4baf25bbbf399d8136 Mon Sep 17 00:00:00 2001 From: Ralf Baechle Date: Wed, 15 Jun 2005 13:00:12 +0000 Subject: [PATCH] Redo RM9000 workaround which along with other DSP ASE changes was causing some headache for debuggers knowing about signal frames. Signed-off-by: Ralf Baechle --- arch/mips/kernel/signal-common.h | 34 +++++++++-- arch/mips/kernel/signal.c | 59 +++++++++---------- arch/mips/kernel/signal32.c | 16 +++++ arch/mips/kernel/signal_n32.c | 32 ++++------ include/asm-mips/cpu-features.h | 11 ---- .../asm-mips/mach-ja/cpu-feature-overrides.h | 6 -- .../mach-ocelot3/cpu-feature-overrides.h | 6 -- .../mach-yosemite/cpu-feature-overrides.h | 6 -- include/asm-mips/war.h | 14 +++++ 9 files changed, 98 insertions(+), 86 deletions(-) diff --git a/arch/mips/kernel/signal-common.h b/arch/mips/kernel/signal-common.h index 3208ff528c..0f66ae5838 100644 --- a/arch/mips/kernel/signal-common.h +++ b/arch/mips/kernel/signal-common.h @@ -160,7 +160,7 @@ restore_sigcontext(struct pt_regs *regs, struct sigcontext *sc) static inline void * get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size) { - unsigned long sp, almask; + unsigned long sp; /* Default to using normal stack */ sp = regs->regs[29]; @@ -176,10 +176,32 @@ get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size) if ((ka->sa.sa_flags & SA_ONSTACK) && (sas_ss_flags (sp) == 0)) sp = current->sas_ss_sp + current->sas_ss_size; - if (PLAT_TRAMPOLINE_STUFF_LINE) - almask = ~(PLAT_TRAMPOLINE_STUFF_LINE - 1); - else - almask = ALMASK; + return (void *)((sp - frame_size) & (ICACHE_REFILLS_WORKAROUND_WAR ? 32 : ALMASK)); +} + +static inline int install_sigtramp(unsigned int __user *tramp, + unsigned int syscall) +{ + int err; - return (void *)((sp - frame_size) & almask); + /* + * Set up the return code ... + * + * li v0, __NR__foo_sigreturn + * syscall + */ + + err = __put_user(0x24020000 + syscall, tramp + 0); + err |= __put_user(0x0000000c , tramp + 1); + if (ICACHE_REFILLS_WORKAROUND_WAR) { + err |= __put_user(0, tramp + 2); + err |= __put_user(0, tramp + 3); + err |= __put_user(0, tramp + 4); + err |= __put_user(0, tramp + 5); + err |= __put_user(0, tramp + 6); + err |= __put_user(0, tramp + 7); + } + flush_cache_sigtramp((unsigned long) tramp); + + return err; } diff --git a/arch/mips/kernel/signal.c b/arch/mips/kernel/signal.c index 8504febf8b..8679ccff87 100644 --- a/arch/mips/kernel/signal.c +++ b/arch/mips/kernel/signal.c @@ -8,6 +8,7 @@ * Copyright (C) 1999, 2000 Silicon Graphics, Inc. */ #include +#include #include #include #include @@ -30,6 +31,7 @@ #include #include #include +#include #include "signal-common.h" @@ -157,26 +159,39 @@ asmlinkage int sys_sigaltstack(nabi_no_regargs struct pt_regs regs) return do_sigaltstack(uss, uoss, usp); } -#if PLAT_TRAMPOLINE_STUFF_LINE -#define __tramp __attribute__((aligned(PLAT_TRAMPOLINE_STUFF_LINE))) -#else -#define __tramp -#endif - +/* + * Horribly complicated - with the bloody RM9000 workarounds enabled + * the signal trampolines is moving to the end of the structure so we can + * increase the alignment without breaking software compatibility. + */ #ifdef CONFIG_TRAD_SIGNALS struct sigframe { u32 sf_ass[4]; /* argument save space for o32 */ - u32 sf_code[2] __tramp; /* signal trampoline */ - struct sigcontext sf_sc __tramp; +#if ICACHE_REFILLS_WORKAROUND_WAR + u32 sf_pad[2]; +#else + u32 sf_code[2]; /* signal trampoline */ +#endif + struct sigcontext sf_sc; sigset_t sf_mask; +#if ICACHE_REFILLS_WORKAROUND_WAR + u32 sf_code[8] ____cacheline_aligned; /* signal trampoline */ +#endif }; #endif struct rt_sigframe { u32 rs_ass[4]; /* argument save space for o32 */ - u32 rs_code[2] __tramp; /* signal trampoline */ - struct siginfo rs_info __tramp; +#if ICACHE_REFILLS_WORKAROUND_WAR + u32 rs_pad[2]; +#else + u32 rs_code[2]; /* signal trampoline */ +#endif + struct siginfo rs_info; struct ucontext rs_uc; +#if ICACHE_REFILLS_WORKAROUND_WAR + u32 rs_code[8] ____cacheline_aligned; /* signal trampoline */ +#endif }; #ifdef CONFIG_TRAD_SIGNALS @@ -273,17 +288,7 @@ void setup_frame(struct k_sigaction * ka, struct pt_regs *regs, if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame))) goto give_sigsegv; - /* - * Set up the return code ... - * - * li v0, __NR_sigreturn - * syscall - */ - if (PLAT_TRAMPOLINE_STUFF_LINE) - __clear_user(frame->sf_code, PLAT_TRAMPOLINE_STUFF_LINE); - err |= __put_user(0x24020000 + __NR_sigreturn, frame->sf_code + 0); - err |= __put_user(0x0000000c , frame->sf_code + 1); - flush_cache_sigtramp((unsigned long) frame->sf_code); + install_sigtramp(frame->sf_code, __NR_sigreturn); err |= setup_sigcontext(regs, &frame->sf_sc); err |= __copy_to_user(&frame->sf_mask, set, sizeof(*set)); @@ -329,17 +334,7 @@ void setup_rt_frame(struct k_sigaction * ka, struct pt_regs *regs, if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame))) goto give_sigsegv; - /* - * Set up the return code ... - * - * li v0, __NR_rt_sigreturn - * syscall - */ - if (PLAT_TRAMPOLINE_STUFF_LINE) - __clear_user(frame->rs_code, PLAT_TRAMPOLINE_STUFF_LINE); - err |= __put_user(0x24020000 + __NR_rt_sigreturn, frame->rs_code + 0); - err |= __put_user(0x0000000c , frame->rs_code + 1); - flush_cache_sigtramp((unsigned long) frame->rs_code); + install_sigtramp(frame->rs_code, __NR_rt_sigreturn); /* Create siginfo. */ err |= copy_siginfo_to_user(&frame->rs_info, info); diff --git a/arch/mips/kernel/signal32.c b/arch/mips/kernel/signal32.c index 8639e24732..806ed073e5 100644 --- a/arch/mips/kernel/signal32.c +++ b/arch/mips/kernel/signal32.c @@ -7,6 +7,7 @@ * Copyright (C) 1994 - 2000 Ralf Baechle * Copyright (C) 1999, 2000 Silicon Graphics, Inc. */ +#include #include #include #include @@ -30,6 +31,7 @@ #include #include #include +#include #define SI_PAD_SIZE32 ((SI_MAX_SIZE/sizeof(int)) - 3) @@ -392,16 +394,30 @@ static int restore_sigcontext32(struct pt_regs *regs, struct sigcontext32 *sc) struct sigframe { u32 sf_ass[4]; /* argument save space for o32 */ +#if ICACHE_REFILLS_WORKAROUND_WAR + u32 sf_pad[2]; +#else u32 sf_code[2]; /* signal trampoline */ +#endif struct sigcontext32 sf_sc; sigset_t sf_mask; +#if ICACHE_REFILLS_WORKAROUND_WAR + u32 sf_code[8] ____cacheline_aligned; /* signal trampoline */ +#endif }; struct rt_sigframe32 { u32 rs_ass[4]; /* argument save space for o32 */ +#if ICACHE_REFILLS_WORKAROUND_WAR + u32 rs_pad[2]; +#else u32 rs_code[2]; /* signal trampoline */ +#endif compat_siginfo_t rs_info; struct ucontext32 rs_uc; +#if ICACHE_REFILLS_WORKAROUND_WAR + u32 rs_code[8] __attribute__((aligned(32))); /* signal trampoline */ +#endif }; int copy_siginfo_to_user32(compat_siginfo_t *to, siginfo_t *from) diff --git a/arch/mips/kernel/signal_n32.c b/arch/mips/kernel/signal_n32.c index 3544208d4b..f47c3aaaec 100644 --- a/arch/mips/kernel/signal_n32.c +++ b/arch/mips/kernel/signal_n32.c @@ -15,6 +15,8 @@ * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ +#include +#include #include #include #include @@ -36,6 +38,7 @@ #include #include #include +#include #include "signal-common.h" @@ -62,17 +65,18 @@ struct ucontextn32 { sigset_t uc_sigmask; /* mask last for extensibility */ }; -#if PLAT_TRAMPOLINE_STUFF_LINE -#define __tramp __attribute__((aligned(PLAT_TRAMPOLINE_STUFF_LINE))) -#else -#define __tramp -#endif - struct rt_sigframe_n32 { u32 rs_ass[4]; /* argument save space for o32 */ - u32 rs_code[2] __tramp; /* signal trampoline */ - struct siginfo rs_info __tramp; +#if ICACHE_REFILLS_WORKAROUND_WAR + u32 rs_pad[2]; +#else + u32 rs_code[2]; /* signal trampoline */ +#endif + struct siginfo rs_info; struct ucontextn32 rs_uc; +#if ICACHE_REFILLS_WORKAROUND_WAR + u32 rs_code[8] ____cacheline_aligned; /* signal trampoline */ +#endif }; save_static_function(sysn32_rt_sigreturn); @@ -137,17 +141,7 @@ void setup_rt_frame_n32(struct k_sigaction * ka, if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame))) goto give_sigsegv; - /* - * Set up the return code ... - * - * li v0, __NR_rt_sigreturn - * syscall - */ - if (PLAT_TRAMPOLINE_STUFF_LINE) - __clear_user(frame->rs_code, PLAT_TRAMPOLINE_STUFF_LINE); - err |= __put_user(0x24020000 + __NR_N32_rt_sigreturn, frame->rs_code + 0); - err |= __put_user(0x0000000c , frame->rs_code + 1); - flush_cache_sigtramp((unsigned long) frame->rs_code); + install_sigtramp(frame->rs_code, __NR_N32_rt_sigreturn); /* Create siginfo. */ err |= copy_siginfo_to_user(&frame->rs_info, info); diff --git a/include/asm-mips/cpu-features.h b/include/asm-mips/cpu-features.h index 4930824a43..bb2212cf46 100644 --- a/include/asm-mips/cpu-features.h +++ b/include/asm-mips/cpu-features.h @@ -109,17 +109,6 @@ #define cpu_has_dsp (cpu_data[0].ases & MIPS_ASE_DSP) #endif -/* - * Certain CPUs may throw bizarre exceptions if not the whole cacheline - * contains valid instructions. For these we ensure proper alignment of - * signal trampolines and pad them to the size of a full cache lines with - * nops. This is also used in structure definitions so can't be a test macro - * like the others. - */ -#ifndef PLAT_TRAMPOLINE_STUFF_LINE -#define PLAT_TRAMPOLINE_STUFF_LINE 0UL -#endif - #ifdef CONFIG_32BIT # ifndef cpu_has_nofpuex # define cpu_has_nofpuex (cpu_data[0].options & MIPS_CPU_NOFPUEX) diff --git a/include/asm-mips/mach-ja/cpu-feature-overrides.h b/include/asm-mips/mach-ja/cpu-feature-overrides.h index 310609c0f4..a0fde405d4 100644 --- a/include/asm-mips/mach-ja/cpu-feature-overrides.h +++ b/include/asm-mips/mach-ja/cpu-feature-overrides.h @@ -37,10 +37,4 @@ #define cpu_icache_line_size() 32 #define cpu_scache_line_size() 32 -/* - * On the RM9000 we need to ensure that I-cache lines being fetches only - * contain valid instructions are funny things will happen. - */ -#define PLAT_TRAMPOLINE_STUFF_LINE 32UL - #endif /* __ASM_MACH_JA_CPU_FEATURE_OVERRIDES_H */ diff --git a/include/asm-mips/mach-ocelot3/cpu-feature-overrides.h b/include/asm-mips/mach-ocelot3/cpu-feature-overrides.h index 1812fc0408..825c5f674d 100644 --- a/include/asm-mips/mach-ocelot3/cpu-feature-overrides.h +++ b/include/asm-mips/mach-ocelot3/cpu-feature-overrides.h @@ -40,10 +40,4 @@ #define cpu_icache_line_size() 32 #define cpu_scache_line_size() 32 -/* - * On the RM9000 we need to ensure that I-cache lines being fetches only - * contain valid instructions are funny things will happen. - */ -#define PLAT_TRAMPOLINE_STUFF_LINE 32UL - #endif /* __ASM_MACH_JA_CPU_FEATURE_OVERRIDES_H */ diff --git a/include/asm-mips/mach-yosemite/cpu-feature-overrides.h b/include/asm-mips/mach-yosemite/cpu-feature-overrides.h index 63e94342e0..463d051f46 100644 --- a/include/asm-mips/mach-yosemite/cpu-feature-overrides.h +++ b/include/asm-mips/mach-yosemite/cpu-feature-overrides.h @@ -37,10 +37,4 @@ #define cpu_icache_line_size() 32 #define cpu_scache_line_size() 32 -/* - * On the RM9000 we need to ensure that I-cache lines being fetches only - * contain valid instructions are funny things will happen. - */ -#define PLAT_TRAMPOLINE_STUFF_LINE 32UL - #endif /* __ASM_MACH_YOSEMITE_CPU_FEATURE_OVERRIDES_H */ diff --git a/include/asm-mips/war.h b/include/asm-mips/war.h index 04ee53b34c..ad374bd3f1 100644 --- a/include/asm-mips/war.h +++ b/include/asm-mips/war.h @@ -176,6 +176,17 @@ #define RM9000_CDEX_SMP_WAR 1 #endif +/* + * The RM9000 has a bug (though PMC-Sierra opposes it being called that) + * where invalid instructions in the same I-cache line worth of instructions + * being fetched may case spurious exceptions. + */ +#if defined(CONFIG_MOMENCO_JAGUAR_ATX) || defined(CONFIG_MOMENCO_OCELOT_3) || \ + defined(CONFIG_PMC_YOSEMITE) +#define ICACHE_REFILLS_WORKAROUND_WAR 1 +#endif + + /* * ON the R10000 upto version 2.6 (not sure about 2.7) there is a bug that * may cause ll / sc and lld / scd sequences to execute non-atomically. @@ -187,6 +198,9 @@ /* * Workarounds default to off */ +#ifndef ICACHE_REFILLS_WORKAROUND_WAR +#define ICACHE_REFILLS_WORKAROUND_WAR 0 +#endif #ifndef R4600_V1_INDEX_ICACHEOP_WAR #define R4600_V1_INDEX_ICACHEOP_WAR 0 #endif -- 2.39.5