[Skiboot] [PATCH v4 14/18] fadump: Introduce new reboot type

[Stewart Smith]

Vasant Hegde <hegdevasant at linux.vnet.ibm.com> writes:
> Enhance reboot2 call to support FADUMP. Payload will call this interface
> to initiate fadump.
>
> Signed-off-by: Vasant Hegde <hegdevasant at linux.vnet.ibm.com>
> ---
>  core/platform.c                        | 4 ++++
>  doc/opal-api/opal-cec-reboot-6-116.rst | 7 +++++++
>  include/opal-api.h                     | 1 +
>  3 files changed, 12 insertions(+)
>
> diff --git a/core/platform.c b/core/platform.c
> index 3282227c1..08f05dc9b 100644
> --- a/core/platform.c
> +++ b/core/platform.c
> @@ -101,6 +101,10 @@ static int64_t opal_cec_reboot2(uint32_t reboot_type, char *diag)
>  	case OPAL_REBOOT_FULL_IPL:
>  		disable_fast_reboot("full IPL reboot requested");
>  		return opal_cec_reboot();
> +	case OPAL_REBOOT_MPIPL:
> +		prlog(PR_ERR, "Kernel requested for fadump\n");
> +		assert(false);
> +		break;
>  	default:
>  		prlog(PR_NOTICE, "OPAL: Unsupported reboot request %d\n", reboot_type);
>  		return OPAL_UNSUPPORTED;
> diff --git a/doc/opal-api/opal-cec-reboot-6-116.rst b/doc/opal-api/opal-cec-reboot-6-116.rst
> index 516d4fc01..11cf54aa1 100644
> --- a/doc/opal-api/opal-cec-reboot-6-116.rst
> +++ b/doc/opal-api/opal-cec-reboot-6-116.rst
> @@ -63,6 +63,13 @@ OPAL_REBOOT_FULL_IPL = 2
>  	On platforms that don't support fast reboot, this is equivalent to a
>  	normal reboot.
>
> +OPAL_REBOOT_MPIPL = 3
> +	Request for fadump reboot. Firmware will reboot the system and collect
> +	dump.
> +
> +	On platforms that don't support fadump, this is equivalent to a
> +	normal assert.

I think a reboot type is the right way to go here, although I was
thinking maybe something not tied to MPIPL itself but something a bit
more generic....

I'm thinking along the lines of "should a dump be taken"... We have
OPAL_REBOOT_PLATFORM_ERROR for when there's something gone wrong on a
platform level (theoretically not the Operating System's fault), maybe
we want OPAL_REBOOT_OS_ERROR ?

With a dump being attempted for OPAL_REBOOT_PLATFORM_ERROR and
OPAL_REBOOT_OS_ERROR reboot types?

A bit of an unanswered question I have is if we should have a fast
reboot path for gathering a dump, as I'm not sure there's much that
would prevent us doing that?

-- 
Stewart Smith
OPAL Architect, IBM.