From d7ff1a90b2d3d122b896056d63db919617e9b6cd Mon Sep 17 00:00:00 2001 From: Sonic Zhang Date: Thu, 5 Mar 2009 18:26:59 +0800 Subject: Blackfin arch: Fix bug - KGDB single step into the middle of a 4 bytes instruction on bf561 after soft bp is hit Run IFLUSH twice to avoid loading wrong instruction after invalidating icache and following sequence is met. 1) The one instruction address is cached in the icache. 2) This instruction in SDRAM is changed. 3) IFLASH[P0] is executed only once in lackfin_icache_flush_range(). 4) This instruction is executed again, but not the changed new one. Signed-off-by: Sonic Zhang Signed-off-by: Bryan Wu --- arch/blackfin/mach-common/cache.S | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) (limited to 'arch/blackfin') diff --git a/arch/blackfin/mach-common/cache.S b/arch/blackfin/mach-common/cache.S index 3c98dacbf289..aa0648c6a9fe 100644 --- a/arch/blackfin/mach-common/cache.S +++ b/arch/blackfin/mach-common/cache.S @@ -66,11 +66,33 @@ /* Invalidate all instruction cache lines assocoiated with this memory area */ ENTRY(_blackfin_icache_flush_range) +/* + * Walkaround to avoid loading wrong instruction after invalidating icache + * and following sequence is met. + * + * 1) One instruction address is cached in the instruction cache. + * 2) This instruction in SDRAM is changed. + * 3) IFLASH[P0] is executed only once in blackfin_icache_flush_range(). + * 4) This instruction is executed again, but the old one is loaded. + */ + P0 = R0; + IFLUSH[P0]; do_flush IFLUSH, , nop ENDPROC(_blackfin_icache_flush_range) /* Flush all cache lines assocoiated with this area of memory. */ ENTRY(_blackfin_icache_dcache_flush_range) +/* + * Walkaround to avoid loading wrong instruction after invalidating icache + * and following sequence is met. + * + * 1) One instruction address is cached in the instruction cache. + * 2) This instruction in SDRAM is changed. + * 3) IFLASH[P0] is executed only once in blackfin_icache_flush_range(). + * 4) This instruction is executed again, but the old one is loaded. + */ + P0 = R0; + IFLUSH[P0]; do_flush FLUSH, IFLUSH ENDPROC(_blackfin_icache_dcache_flush_range) -- cgit v1.2.3