On 15/02/19 3:21 AM, Andrew F. Davis wrote:
On 2/13/19 9:32 PM, Lokesh Vutla wrote:
On 14/02/19 12:07 AM, Andrew F. Davis wrote:
On HS devices the 512b region of reset isolated memory called MCU_PSRAM0 is firewalled by default. Until SYSFW is loaded we cannot use this memory. It is only used to store a single value left at the end of SRAM by ROM that will be needed later. Save that value to a global variable stored in the .data section. This section is used as .bss will be cleared between saving this value and using it.
Signed-off-by: Andrew F. Davis afd@ti.com
arch/arm/mach-k3/am6_init.c | 8 +++----- arch/arm/mach-k3/include/mach/am6_hardware.h | 3 --- 2 files changed, 3 insertions(+), 8 deletions(-)
diff --git a/arch/arm/mach-k3/am6_init.c b/arch/arm/mach-k3/am6_init.c index a5553190b4..462538e45d 100644 --- a/arch/arm/mach-k3/am6_init.c +++ b/arch/arm/mach-k3/am6_init.c @@ -49,11 +49,11 @@ static void ctrl_mmr_unlock(void) mmr_unlock(CTRL_MMR0_BASE, 7); }
+u32 bootindex __attribute__((section(".data")));
After thinking a bit more I realized that backup bootmode might fail. R5 SPL is fine but when it jumps to A53 SPL it is trying to read the bootindex again from K3_BOOT_PARAM_TABLE_INDEX_VAL(this is already the case and is wrong). It is not guaranteed that R5 SPL did not damage this ROM param table. We should somehow pass bootindex to A53 SPL using scratchpad space.
I don't know of any super good way to pass data from R5-SPL to A53-SPL, but I don't think MCU_PSRAM0 will be the way to do it. For all we know
Agreed.
before A53-SPL has started the R5-SPL may have shutdown and something else has booted, which could have used that MCU local RAM space. I think we need something that gets passed to A53 anyway, maybe a DT fixup?
Yeah or we can update spl_boot_list array with both primary and secondary bootdevices.
Actually this patch as such has no issues and is not introducing any new regressions.
Reviewed-by: Lokesh Vutla lokeshvutla@ti.com
For backup boot modes Ill take a look and try to address in a cleaner way.
Thanks and regards, Lokesh