AM6442: OSPI SBL authentication failure

Hi Marc,

Marc Schouteeten said:

Can it have something to do with this?

Ideally, this shouldn't be the case.

However, could you please confirm if the authentication of the multicore image was successful & the image was booting fine when the image was of lesser size. And you now see the failure only when multicore image size grew to be of 0x180000?

Regards,

Prashant

Hi Marc,

Marc Schouteeten said:

Can it have something to do with this?

I have tested and this is not the case at least with TI EVM. So, I tested the authentication of a random 2MB file using SBL_OSPI and here are the results

DMSC Firmware Version 9.0.7--v09.00.07 (Kool Koala)
DMSC Firmware revision 0x9
DMSC ABI revision 3.1

Length of certificate: 1654
Length of image: 2097152
Image authentication successful...

The custom output was generated with the following changes:

diff --git a/source/drivers/bootloader/bootloader.c b/source/drivers/bootloader/bootloader.c
index 3aa46db1..e0088360 100644
--- a/source/drivers/bootloader/bootloader.c
+++ b/source/drivers/bootloader/bootloader.c
@@ -578,7 +578,16 @@ int32_t Bootloader_verifyMulticoreImage(Bootloader_Handle handle)
             }
             else
             {
+                DebugP_log("Length of certificate: %d\r\n", certLen);
+                DebugP_log("Length of image: %d\r\n", imageLen);
+
                 authStatus = Bootloader_socAuthImage(certLoadAddr);
+                
+                DebugP_assert(authStatus == SystemP_SUCCESS);
+                DebugP_log("Image authentication successful...\r\n\r\n");
+
+                /* Do not go further */
+                while(1);
             }
 
             /* Invalidate the cache before reading in case HSM decrypted image */

Regards,

Prashant

We are using the "uart_uniflash.py" script to upload a new firmware to our terminal console via serial port.

As it turns out, this python script has a size limitation of 1Mbyte...

BOOTLOADER_UNIFLASH_BUF_SIZE                         = 1024*1024

increasing this size solves the programming issue...

(our workaround was to upload via tftp)

Hi Marc,

I am not able to connect the dots here.

Initially you reported the authentication failure while working with OSPI bootloader. I assumed this occured when your OSPI bootloader tries to authenticate the multicore appimage from OSPI media itself. Then, you found a workaround for this and probably solved it.

However, with the latest comment, I am unable to understand how the `uart_uniflash.py` comes into the picture here and so what really was the issue since the start. Could you please help me understand?

Thanks!  

Hi Marc,

Thanks a lot for the explanation. I now have the clear understanding.

Actually, the `uart_uniflash.py` script is designed to send a file in chunks of 1MB if file size is greater than 1MB. The `sbl_uart_uniflash` then running at the board respects this design and flashes the image in chunks of 1MB. In case you are using your custom application to flash images, there might have come an incompatibility in the design which resulted in the issue.

Anyways, simply increasing the chunk size works. Happy that the issue is solved...

Regards,

Prashant