MCU-PLUS-SDK-AM243X: Disable Bootloader scratch memory - BOOTLOADER_SCRATCH_MEM_ENABLE define

Vaclav Honzik

Tool/software:

Hello,
I am using AM243x MCU+ SDK 11.01.00 with SysCfg 1.22 on AM243X-LP. Debug build of my application has reached a "critical mass" where it barely fits available RAM memory. I have noticed that my bootloader (largely based on examples\drivers\boot\sbl_ospi_multi_partition\am243x-lp) has started failing so I was debugging the issue and noticed that in SDK in Bootloader_verifyMulticoreImage() (source\drivers\bootloader\bootloader.c line 595) due to scratch memory being enabled, the whole image is copied to RAM for image verification, which is problematic for me.

First of all, did I miss a setting in SysCfg for disabling scratch memory for bootloader?

I went ahead and set BOOTLOADER_SCRATCH_MEM_ENABLE to 0 in SDK in source\drivers\bootloader.h, recompiled the SDK and no change has occurred. So, I did more digging and in my SysCfg generated files in my bootloader source files (ti-arm-clang\generated\ti_drivers_config.c), gBootloaderConfig array is filled with Bootloader_Config initializations that use BOOTLOADER_SCRATCH_MEM_ENABLE for enableScratchMem member. Therefore, the following code in SDK in bootloader.c 595:

// config->enableScratchMem is set to BOOTLOADER_SCRATCH_MEM_ENABLE by SysCfg
if(config->enableScratchMem == BOOTLOADER_SCRATCH_MEM_ENABLE){

has a little bit of 0U == 0U or 1U == 1U going on, which I found amusing to be honest when I found out

This seems like a bug to me unless I missed something. I have workarounds, such as compiling SDK and my bootloader with different BOOTLOADER_SCRATCH_MEM_ENABLE values or better changing the above if statement to config->enableScratchMem == 1U. This is all assuming disabling scratch memory is intended to be possible right?

Cheers,
Vaclav

4 months ago

0 Meet Thakar 4 months ago

TI__Genius 15605 points

Hi Vaclav,

You can disable the scratch memory support by removing the following MACRO definition in bootloader_soc.h: https://github.com/TexasInstruments/mcupsdk-core/blob/next/source/drivers/bootloader/soc/am64x_am243x/bootloader_soc.h#L45

Best Regards,

Meet.

0 Vaclav Honzik 4 months ago in reply to Meet Thakar

Prodigy 55 points

Thanks for a quick reply Meet,
disabling //#define BOOTLOADER_SCRATCH_MEM_SUPPORT in https://github.com/TexasInstruments/mcupsdk-core/blob/next/source/drivers/bootloader/soc/am64x_am243x/bootloader_soc.h#L45 does not compile in my SDK version because the now unavailable gMemBootloaderArgs is being used "un-protected" by BOOTLOADER_SCRATCH_MEM_SUPPORT in https://github.com/TexasInstruments/mcupsdk-core/blob/next/source/drivers/bootloader/bootloader.c#L753. Note the wrapping macro DRV_VERSION_MMCSD_V0 is enabled in https://github.com/TexasInstruments/mcupsdk-core/blob/next/source/drivers/hw_include/am64x_am243x/soc_config.h#L96. Compiler output:

 Compiling: drivers.am243x.r5f.ti-arm-clang.release.lib: bootloader/bootloader_flash.c
bootloader/bootloader.c:753:21: error: use of undeclared identifier 'gMemBootloaderArgs'
  753 |                     gMemBootloaderArgs.appImageBaseAddr = (uint32_t)(config->scratchMemPtr) + certLen;
      |                     ^
bootloader/bootloader.c:754:21: error: use of undeclared identifier 'gMemBootloaderArgs'
  754 |                     gMemBootloaderArgs.curOffset = 0U;
      |                     ^
bootloader/bootloader.c:757:37: error: use of undeclared identifier 'gMemBootloaderArgs'
  757 |                     config->args = &gMemBootloaderArgs;
      |

+1 Meet Thakar 4 months ago in reply to Vaclav Honzik

TI__Genius 15605 points

This error is due to the following piece of code: https://github.com/TexasInstruments/mcupsdk-core/blob/next/source/drivers/bootloader/bootloader.c#L87

A better option to disable this is to set enableScratchMem to 0 in bootConfig and set scratchMemPtr to NULL in the main.c of SBL OSPI MULTIPARTITION. Please refer to the following patch:

diff --git a/examples/drivers/boot/sbl_ospi_multi_partition/am243x-evm/r5fss0-0_nortos/main.c b/examples/drivers/boot/sbl_ospi_multi_partition/am243x-evm/r5fss0-0_nortos/main.c
index e1a6d835..975cdd90 100644
--- a/examples/drivers/boot/sbl_ospi_multi_partition/am243x-evm/r5fss0-0_nortos/main.c
+++ b/examples/drivers/boot/sbl_ospi_multi_partition/am243x-evm/r5fss0-0_nortos/main.c
@@ -91,7 +91,8 @@ int32_t App_bootCpu(uint32_t bootDrvInstanceId, uint32_t cpuId)
 
     bootHandle = Bootloader_open(bootDrvInstanceId, &bootParams);
     bootConfig = (Bootloader_Config *)bootHandle;
-    bootConfig->scratchMemPtr = gAppimage;
+    bootConfig->enableScratchMem = 0;
+    bootConfig->scratchMemPtr = NULL;
 
     if(bootHandle != NULL)
     {
@@ -120,7 +121,9 @@ int32_t App_bootLoadSelfCpu(uint32_t bootDrvInstanceId, uint32_t cpuId)
 
     bootHandle = Bootloader_open(bootDrvInstanceId, &bootParams);
     bootConfig = (Bootloader_Config *)bootHandle;
-    bootConfig->scratchMemPtr = gAppimage;
+    bootConfig->enableScratchMem = 0;
+    bootConfig->scratchMemPtr = NULL;
+    
     if(bootHandle != NULL)
     {
         status = Bootloader_parseMultiCoreAppImage(bootHandle, &bootImageInfo);

Please keep the MACRO definition of BOOTLOADER_SCRATCH_MEM_SUPPORT as it is.

Best Regards,

Meet.

0 Vaclav Honzik 4 months ago in reply to Meet Thakar

Prodigy 55 points

That worked great. I should have realized I have access to the Bootloader_Config structures in my bootloader code. The macro definitions in TI SDK are little suspicious, but I have a good solution now. Thanks a lot!

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MCU-PLUS-SDK-AM243X: Disable Bootloader scratch memory - BOOTLOADER_SCRATCH_MEM_ENABLE define