From 09b5a10c1944214a6008712bfa92b29f00b84a1a Mon Sep 17 00:00:00 2001 From: Chris Smith Date: Wed, 2 Jul 2008 15:17:11 +0900 Subject: sh: Optimized flush_icache_range() implementation. Add implementation of flush_icache_range() suitable for signal handler and kprobes. Remove flush_cache_sigtramp() and change signal.c to use flush_icache_range(). Signed-off-by: Chris Smith Signed-off-by: Paul Mundt --- arch/sh/kernel/signal_32.c | 10 ++----- arch/sh/mm/cache-sh4.c | 67 +++++++++++++++++++++++++--------------------- 2 files changed, 38 insertions(+), 39 deletions(-) (limited to 'arch') diff --git a/arch/sh/kernel/signal_32.c b/arch/sh/kernel/signal_32.c index 46170a9a7221..eee29257a8ae 100644 --- a/arch/sh/kernel/signal_32.c +++ b/arch/sh/kernel/signal_32.c @@ -398,10 +398,7 @@ static int setup_frame(int sig, struct k_sigaction *ka, pr_debug("SIG deliver (%s:%d): sp=%p pc=%08lx pr=%08lx\n", current->comm, task_pid_nr(current), frame, regs->pc, regs->pr); - flush_cache_sigtramp(regs->pr); - - if ((-regs->pr & (L1_CACHE_BYTES-1)) < sizeof(frame->retcode)) - flush_cache_sigtramp(regs->pr + L1_CACHE_BYTES); + flush_icache_range(regs->pr, regs->pr + sizeof(frame->retcode)); return 0; @@ -486,10 +483,7 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, pr_debug("SIG deliver (%s:%d): sp=%p pc=%08lx pr=%08lx\n", current->comm, task_pid_nr(current), frame, regs->pc, regs->pr); - flush_cache_sigtramp(regs->pr); - - if ((-regs->pr & (L1_CACHE_BYTES-1)) < sizeof(frame->retcode)) - flush_cache_sigtramp(regs->pr + L1_CACHE_BYTES); + flush_icache_range(regs->pr, regs->pr + sizeof(frame->retcode)); return 0; diff --git a/arch/sh/mm/cache-sh4.c b/arch/sh/mm/cache-sh4.c index 43d7ff6b6ec7..1fdc8d90254a 100644 --- a/arch/sh/mm/cache-sh4.c +++ b/arch/sh/mm/cache-sh4.c @@ -4,6 +4,7 @@ * Copyright (C) 1999, 2000, 2002 Niibe Yutaka * Copyright (C) 2001 - 2007 Paul Mundt * Copyright (C) 2003 Richard Curnow + * Copyright (c) 2007 STMicroelectronics (R&D) Ltd. * * This file is subject to the terms and conditions of the GNU General Public * License. See the file "COPYING" in the main directory of this archive @@ -22,6 +23,7 @@ * entirety. */ #define MAX_DCACHE_PAGES 64 /* XXX: Tune for ways */ +#define MAX_ICACHE_PAGES 32 static void __flush_dcache_segment_1way(unsigned long start, unsigned long extent); @@ -178,42 +180,45 @@ void __flush_invalidate_region(void *start, int size) /* * Write back the range of D-cache, and purge the I-cache. * - * Called from kernel/module.c:sys_init_module and routine for a.out format. + * Called from kernel/module.c:sys_init_module and routine for a.out format, + * signal handler code and kprobes code */ void flush_icache_range(unsigned long start, unsigned long end) { - flush_cache_all(); -} - -/* - * Write back the D-cache and purge the I-cache for signal trampoline. - * .. which happens to be the same behavior as flush_icache_range(). - * So, we simply flush out a line. - */ -void __uses_jump_to_uncached flush_cache_sigtramp(unsigned long addr) -{ - unsigned long v, index; - unsigned long flags; + int icacheaddr; + unsigned long flags, v; int i; - v = addr & ~(L1_CACHE_BYTES-1); - asm volatile("ocbwb %0" - : /* no output */ - : "m" (__m(v))); - - index = CACHE_IC_ADDRESS_ARRAY | - (v & boot_cpu_data.icache.entry_mask); - - local_irq_save(flags); - jump_to_uncached(); - - for (i = 0; i < boot_cpu_data.icache.ways; - i++, index += boot_cpu_data.icache.way_incr) - ctrl_outl(0, index); /* Clear out Valid-bit */ - - back_to_cached(); - wmb(); - local_irq_restore(flags); + /* If there are too many pages then just blow the caches */ + if (((end - start) >> PAGE_SHIFT) >= MAX_ICACHE_PAGES) { + flush_cache_all(); + } else { + /* selectively flush d-cache then invalidate the i-cache */ + /* this is inefficient, so only use for small ranges */ + start &= ~(L1_CACHE_BYTES-1); + end += L1_CACHE_BYTES-1; + end &= ~(L1_CACHE_BYTES-1); + + local_irq_save(flags); + jump_to_uncached(); + + for (v = start; v < end; v+=L1_CACHE_BYTES) { + asm volatile("ocbwb %0" + : /* no output */ + : "m" (__m(v))); + + icacheaddr = CACHE_IC_ADDRESS_ARRAY | ( + v & cpu_data->icache.entry_mask); + + for (i = 0; i < cpu_data->icache.ways; + i++, icacheaddr += cpu_data->icache.way_incr) + /* Clear i-cache line valid-bit */ + ctrl_outl(0, icacheaddr); + } + + back_to_cached(); + local_irq_restore(flags); + } } static inline void flush_cache_4096(unsigned long start, -- cgit v1.2.1