On Tuesday 26 October 2021 16:21:02 Stefan Roese wrote:
On 26.10.21 14:40, Pali Rohár wrote:
My another guess there could be a problem is usage of stack. Maybe it is possible that register with stack pointer is not initialized after the full transfer when going to execute main image. Same arm baudrate change code is used after the SPL and before main U-Boot, and the first instruction is "push". Maybe modifying the arm code to not use stack when switching the baudrate back to 115200 could also help. I will look at it.
Thanks.
Here is dirty hack patch which completely disable calling code for changing baudrate back to 115200 on ARM side:
diff --git a/tools/kwboot.c b/tools/kwboot.c index 5f4ff673972e..00d58a239c71 100644 --- a/tools/kwboot.c +++ b/tools/kwboot.c @@ -1070,17 +1070,17 @@ kwboot_xmodem(int tty, const void *_img, size_t size, int baudrate) return rc;
if (baudrate) { - char buf[sizeof(kwb_baud_magic)]; - - kwboot_printv("Waiting 1s for baudrate change magic\n"); - rc = kwboot_tty_recv(tty, buf, sizeof(buf), 1000); - if (rc) - return rc; - - if (memcmp(buf, kwb_baud_magic, sizeof(buf))) { - errno = EPROTO; - return -1; - } +// char buf[sizeof(kwb_baud_magic)]; +// +// kwboot_printv("Waiting 1s for baudrate change magic\n"); +// rc = kwboot_tty_recv(tty, buf, sizeof(buf), 1000); +// if (rc) +// return rc; +// +// if (memcmp(buf, kwb_baud_magic, sizeof(buf))) { +// errno = EPROTO; +// return -1; +// }
kwboot_printv("\nChanging baudrate back to 115200 Bd\n\n"); rc = kwboot_tty_change_baudrate(tty, 115200); @@ -1551,8 +1551,8 @@ kwboot_img_patch(void *img, size_t *size, int baudrate) * This code is appended after the data part of the image and * execaddr is changed to execute this code before U-Boot proper. */ - kwboot_printv("Injecting code for changing baudrate back\n"); - _copy_baudrate_change_code(hdr, size, 1, baudrate, 115200); +// kwboot_printv("Injecting code for changing baudrate back\n"); +// _copy_baudrate_change_code(hdr, size, 1, baudrate, 115200);
/* recompute header size */ hdrsz = kwbheader_size(hdr);
As main U-Boot binary on ARM resets UART, it means that baudrate is properly set to 115200. Probably beginning of the U-Boot output could be lost but at least console should start.
Could you try this patch if it starts working now?