diff options
Diffstat (limited to 'plat/arm/css/common/css_scp_bootloader.c')
| -rw-r--r-- | plat/arm/css/common/css_scp_bootloader.c | 15 |
1 files changed, 8 insertions, 7 deletions
diff --git a/plat/arm/css/common/css_scp_bootloader.c b/plat/arm/css/common/css_scp_bootloader.c index 8bfaa87c..d3f671e2 100644 --- a/plat/arm/css/common/css_scp_bootloader.c +++ b/plat/arm/css/common/css_scp_bootloader.c @@ -77,10 +77,10 @@ static void scp_boot_message_start(void) static void scp_boot_message_send(size_t payload_size) { - /* Make sure payload can be seen by SCP */ - if (MHU_PAYLOAD_CACHED) - flush_dcache_range(BOM_SHARED_MEM, - sizeof(bom_cmd_t) + payload_size); + /* Ensure that any write to the BOM payload area is seen by SCP before + * we write to the MHU register. If these 2 writes were reordered by + * the CPU then SCP would read stale payload data */ + dmbst(); /* Send command to SCP */ mhu_secure_message_send(BOM_MHU_SLOT_ID); @@ -99,9 +99,10 @@ static uint32_t scp_boot_message_wait(size_t size) panic(); } - /* Make sure we see the reply from the SCP and not any stale data */ - if (MHU_PAYLOAD_CACHED) - inv_dcache_range(BOM_SHARED_MEM, size); + /* Ensure that any read to the BOM payload area is done after reading + * the MHU register. If these 2 reads were reordered then the CPU would + * read invalid payload data */ + dmbld(); return *(uint32_t *) BOM_SHARED_MEM; } |