[U-Boot] [PATCH] tools: kwboot: Make kwboot more robust on a38x

[Baruch Siach]

Hi Chris,

Chris Packham writes:
> On Tue, Aug 14, 2018 at 3:25 AM Baruch Siach <baruch at tkos.co.il> wrote:
>> From: Jon Nettleton <jon at solid-run.com>
>>
>> This patch accomplishes 2 things to make the kwboot procedure
>> on the a38x more reliable.
>>
>> 1)  We fill the tty with 1K of the magic bootparam.  This helps
>> with the timing of where the microcode picks up in the read of
>> the line to ensure we actually catch the break to go into recovery
>> mode
>>
>> 2)  Before starting the xmodem transfer we sleep for 2 seconds
>> and then flush the line.  This allows all the magic bootparam
>> to be flushed from the line and makes the xmodem transfer reliable
>> and removes the Bad message failures.
>>
>> Signed-off-by: Jon Nettleton <jon at solid-run.com>
>> Signed-off-by: Baruch Siach <baruch at tkos.co.il>
>> ---
>
> Reviewed-by: Chris Packham <judge.packham at gmail.com>

Thanks.

> Lately I haven't had much luck with using kwboot on a38x. I seem to be
> able to get the spl to boot from uart (even better now thanks to this
> patch) but the next stage still loads from SPI. I haven't been brave
> enough to blank a board to see if that changes behaviour. Are your
> experiences any different? I'm wondering if there is something we need
> to do in the SPL to figure out that we need to load the next stage via
> xmodem.

It works for me here on the Clearfog.

The code that determines the seconds stage load device is in
arch/arm/mach-mvebu/spl.c:get_boot_device(). Does the code there get it
right? What do you read from CONFIG_BOOTROM_ERR_REG?

baruch

>>  tools/kwboot.c | 14 ++++++++++----
>>  1 file changed, 10 insertions(+), 4 deletions(-)
>>
>> diff --git a/tools/kwboot.c b/tools/kwboot.c
>> index 50ae2b4b77b1..4be094c9c8d8 100644
>> --- a/tools/kwboot.c
>> +++ b/tools/kwboot.c
>> @@ -286,6 +286,7 @@ kwboot_bootmsg(int tty, void *msg)
>>  {
>>         int rc;
>>         char c;
>> +       int count;
>>
>>         if (msg == NULL)
>>                 kwboot_printv("Please reboot the target into UART boot mode...");
>> @@ -297,10 +298,12 @@ kwboot_bootmsg(int tty, void *msg)
>>                 if (rc)
>>                         break;
>>
>> -               rc = kwboot_tty_send(tty, msg, 8);
>> -               if (rc) {
>> -                       usleep(msg_req_delay * 1000);
>> -                       continue;
>> +               for (count = 0; count < 128; count++) {
>> +                       rc = kwboot_tty_send(tty, msg, 8);
>> +                       if (rc) {
>> +                               usleep(msg_req_delay * 1000);
>> +                               continue;
>> +                       }
>>                 }
>>
>>                 rc = kwboot_tty_recv(tty, &c, 1, msg_rsp_timeo);
>> @@ -426,6 +429,9 @@ kwboot_xmodem(int tty, const void *_data, size_t size)
>>
>>         kwboot_printv("Sending boot image...\n");
>>
>> +       sleep(2); /* flush isn't effective without it */
>> +       tcflush(tty, TCIOFLUSH);
>> +
>>         do {
>>                 struct kwboot_block block;
>>                 int n;

-- 
     http://baruch.siach.name/blog/                  ~. .~   Tk Open Systems
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