On 15/03/2013 18:27, Wolfgang Denk wrote:
Dear Stefano Babic,
Hi Wolfgang,
I agree that it is important information, and there should be a way that the user can get at this information. But I see no urgent need to print this for everyboot, where it is just costing us precious boot time (yes, it's only a few milliseconds, but they are trivial to save).
That was why I suggested to add thjis information for example to the output of the "bdinfo" command.
That is fine - but then it should be consistent. We have tried to have a consistent API between SOCs (I mean: iMX SOCs), that is, each SOC in the i.MX family should implement the same functions and not invent a new one, And the behavior must beconsistent, too. I know we are far away to be perfect, and some code can be further factorized (this was the reason to add imx_common).
To the specific case, each i.MX SOC implements a get_reset_cause() function:
arch/arm/cpu/arm1136/mx31/generic.c:static char *get_reset_cause(void) arch/arm/cpu/arm1136/mx31/generic.c: printf("Reset cause: %s\n",
arch/arm/cpu/arm1136/mx35/generic.c:static char *get_reset_cause(void) arch/arm/cpu/arm1136/mx35/generic.c: printf("Reset cause: %s\n", get_reset_cause());
arch/arm/cpu/arm926ejs/mx25/generic.c:static char *get_reset_cause(void) arch/arm/cpu/arm926ejs/mx25/generic.c: printf("Reset cause: %s\n\n",
arch/arm/imx-common/cpu.c:char *get_reset_cause(void) arch/arm/imx-common/cpu.c: printf("Reset cause: %s\n", get_reset_cause());
Checking this I see also that the mx53loco does not use general code (bad !):
board/freescale/mx53loco/mx53loco.c: printf("Reset cause: %s\n",
It is ok to move the information to bdinfo, but then it should not break the consistence: all i.MX should follow the same rule. This makes also easier for board maintainers to switch from a SOC to the next one, because they have to provide quite the same functions in their code (and using the same functions, too.).
BTW: if I type "reset", I will get a message "Reset cause: WDOG". I know why, but most users will not know thy they see a watchdog reset here, so actually this information may be more confusing than helpful in a number of cases (which is IMO one more reason to not always to display it - it saves us a number of unproductive support requests).
I agree with you that this should be done by a separate patchset: it is not related to the Wandboard. But if we go on this way, the same changes should be done for all i.MX, not only for i.MX5/i.MX6.
Best regards, Stefano Babic