[PATCH v3] configs: am57xx_hs_evm_defconfig: Reserve EMIF memory used by PPA

[Beleswar Padhi]

The AM571x SoC has 1 GB DDR space. As part of normal re-location process
U-Boot copies itself to the top of DDR bank. However, on HS devices, the
top 37 MB is used by PPA and is firewalled. This results in an exception
and the boot fails. Set CONFIG_SYS_MEM_TOP_HIDE to reserve the top 38 MB
memory (aligned to 2MB as per page size for ARM32) to fix the boot.

Note: This limitation does not exist for other AM57x devices, but this
config is applied in the common defconfig since adding a separate
defconfig only for AM571x is not justified. Losing 38MB of memory at the
bootloader stage on other devices is acceptable.

Signed-off-by: Beleswar Padhi <b-padhi at ti.com>
---
Fix boot for TI AM571x HS EVM board

v3: Changelog:
1. Carry the changes in the common am57xx_hs_evm_defconfig file

Link to v2:
https://lore.kernel.org/all/20251128150455.3279166-1-b-padhi@ti.com/

v2: Changelog:
1. Drop [PATCH v1 2/2] in v2 series. There is no need to add reserved
memory node in DT as it is done by U-Boot as part of FDT fixups
https://github.com/u-boot/u-boot/blob/master/arch/arm/mach-omap2/fdt-common.c#L72-L107
2. Add entry in MAINTAINERS for new config.
3. Update commit message to use memory size in MB than raw hex bytes

Link to v1:
https://lore.kernel.org/all/20251128064353.1295063-1-b-padhi@ti.com/

Test logs:
https://gist.github.com/3V3RYONE/e86b3f4551986b0400d0e0f66d6ecc66

 configs/am57xx_hs_evm_defconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/configs/am57xx_hs_evm_defconfig b/configs/am57xx_hs_evm_defconfig
index 6e4704470e8..3db30d2397e 100644
--- a/configs/am57xx_hs_evm_defconfig
+++ b/configs/am57xx_hs_evm_defconfig
@@ -16,6 +16,7 @@ CONFIG_SPL=y
 CONFIG_SPL_SPI_FLASH_SUPPORT=y
 CONFIG_SPL_SPI=y
 CONFIG_ARMV7_LPAE=y
+CONFIG_SYS_MEM_TOP_HIDE=0x2600000
 CONFIG_AHCI=y
 CONFIG_SPL_LOAD_FIT=y
 CONFIG_DISTRO_DEFAULTS=y
-- 
2.34.1