Halting auto-boot process in the U-Boot shell https://lore.kernel.org/u-boot/20220614060203.33600-1-heinrich.schuchardt at canonical.com/

[Heinrich Schuchardt]

On 2/26/25 07:48, Kummari, Prasad wrote:
> [AMD Official Use Only - AMD Internal Distribution Only]
> 
> 
> Hi Heinrich,
> 
> Regarding below commit.
> 
> commit 68edbed454b863dbcd197e19e1ab26a0a05c7d85
> Author:     Heinrich Schuchardt <xypron.glpk at gmx.de>
> AuthorDate: Tue Jun 14 08:02:03 2022 +0200
> Commit:     Heinrich Schuchardt <xypron.glpk at gmx.de>
> CommitDate: Sun Jun 19 15:53:09 2022 +0200
> 
>      efi_loader: initialize console size late
> 
>      If CONFIG_VIDEO_DM=n we query the display size from the serial console.
>      Especially when using a remote console the response can be so late that
>      it interferes with autoboot.
> 
> *    Only query the console size when running an EFI binary.*
> 
> https://lore.kernel.org/u-boot/20220614060203.33600-1- 
> heinrich.schuchardt at canonical.com/ <https://lore.kernel.org/u- 
> boot/20220614060203.33600-1-heinrich.schuchardt at canonical.com/>
> 
> Commit 68edbed454b863dbcd197e19e1ab26a0a05c7d85 modifies the system to 
> query the console size only when running an EFI binary. However, when 
> CONFIG_EFI_CAPSULE_ON_DISK is enabled, the console is still being 
> invoked, which shouldn't happen. This results in issues on our terminal, 
> which cannot handle the resulting characters, leading to incorrect 
> display and halting the auto-boot process in the U-Boot shell.
> 
> *Log Output:*
> 
> Warning: ethernet at ff0c0000 (eth0) using random MAC address - 
> ee:df:0a:38:a8:c4
> 
> eth0: ethernet at ff0c0000, eth1: mrmac at a40f0000, eth2: mrmac at a40f1000, 
> eth3: mrmac at a40f2000, eth4: mrmac at a40f3000
> 
> Cannot persist EFI variables without system partition
> 
> Missing TPMv2 device for EFI_TCG_PROTOCOL
> 
> Missing RNG device for EFI_RNG_PROTOCOL
> 
> Hit any key to stop autoboot:  0
> 
> *Versal> [42;173R*
> 
> *Unknown command '[42' - try 'help'*

Hello Prasad,

The terminal emulation seems to be sending a valid reply indicating 42 
rows and 173 columns.

It could be that in your setup you are hitting the time out in 
term_get_char().

Could you, please, check what happens if you apply

--- a/lib/efi_loader/efi_console.c
+++ b/lib/efi_loader/efi_console.c
@@ -92,8 +92,7 @@ static int term_get_char(s32 *c)
         timeout = timer_get_us() + 100000;

         while (!tstc())
-               if (timer_get_us() > timeout)
-                       return 1;
+               ;

         *c = getchar();
         return 0;

If the failure disappears, next you would have to analyze why the 
timeout is occurring (e.g. timer_get_us() running too fast).

If you still get failures, please, add debug output term_read_reply() to 
understand what is happening.

Best regards

Heinrich

> 
> *Unknown command '173R' - try 'help'*
> 
> *Versal>*
> 
> Debug logs:
> 
> Before entering the U-Boot shell, set a breakpoint at getc, which is 
> invoked by efi_setup_console_size() and display problems and auto-boot 
> interruptions.
> 
>   xsdb% bt
>      0  0x7ff0d648 pl01x_serial_getc()+2011873280: drivers/serial/ 
> serial_pl01x.c, line 339
>      1  0x7ff0d134 __serial_getc()+2011873316: drivers/serial/serial- 
> uclass.c, line 310
> *    2  0x7ff47dcc efi_setup_console_size()+2011873540: lib/efi_loader/ 
> efi_console.c, line 291
> *    3  0x7ff4e40c efi_init_obj_list()+2011873316: lib/efi_loader/ 
> efi_setup.c, line 225
>      4  0x7fed699c main_loop()+2011873324: common/main.c, line 61
>      5  0x7fed69d8 add_mem_region()+2011873280: common/main.c, line 84
> xsdb%
> 
> code snippet: Disabling the efi_setup_console_size() function prevents 
> the issue from occurring.
> 
> diff --git a/lib/efi_loader/efi_setup.c b/lib/efi_loader/efi_setup.c
> index aa59bc7779d..ad68ac19526 100644
> --- a/lib/efi_loader/efi_setup.c
> +++ b/lib/efi_loader/efi_setup.c
> @@ -220,9 +220,10 @@ efi_status_t efi_init_obj_list(void)
>          /* Initialize once only */
>          if (efi_obj_list_initialized != OBJ_LIST_NOT_INITIALIZED)
>                  return efi_obj_list_initialized;
> -
> +#if 0
>          /* Set up console modes */
>          efi_setup_console_size();
> +#endif
> 
> Regards,
> 
> Prasad.
>