From 442e2506b1d535c9420a29066f5d9c8fb11de35a Mon Sep 17 00:00:00 2001 From: Matthias Welwarsky Date: Thu, 29 Oct 2015 13:09:29 +0100 Subject: cortex_a: force cache and tlb bypass when cpu is in debug state for minimal impact on the hardware state, force all memory accesses to bypass the caches and tlbs. This may actually be the default, but ARM recommends in DDI0406C to set proper default values on debug init. Change-Id: If5ac097b6ee725c047b1e86c2f90eabe16b98c7b Signed-off-by: Matthias Welwarsky Reviewed-on: http://openocd.zylin.com/3079 Reviewed-by: Paul Fertser Tested-by: jenkins --- src/target/cortex_a.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'src/target/cortex_a.c') diff --git a/src/target/cortex_a.c b/src/target/cortex_a.c index 5268cf21..61a5df38 100644 --- a/src/target/cortex_a.c +++ b/src/target/cortex_a.c @@ -243,6 +243,18 @@ static int cortex_a_init_debug_access(struct target *target) if (retval != ERROR_OK) return retval; + /* Disable cacheline fills and force cache write-through in debug state */ + retval = mem_ap_sel_write_atomic_u32(swjdp, armv7a->debug_ap, + armv7a->debug_base + CPUDBG_DSCCR, 0); + if (retval != ERROR_OK) + return retval; + + /* Disable TLB lookup and refill/eviction in debug state */ + retval = mem_ap_sel_write_atomic_u32(swjdp, armv7a->debug_ap, + armv7a->debug_base + CPUDBG_DSMCR, 0); + if (retval != ERROR_OK) + return retval; + /* Enabling of instruction execution in debug mode is done in debug_entry code */ /* Resync breakpoint registers */ -- cgit v1.2.3-18-g5258