Re: [PATCH] powerpc/powernv: Make possible for user to force a full ipl cec reboot
From: Stewart Smith <hidden>
Date: 2018-09-10 04:37:23
Vaibhav Jain [off-list ref] writes:
Ever since fast reboot is enabled by default in opal, opal_cec_reboot() will use fast-reset instead of full IPL to perform system reboot. This leaves the user with no direct way to force a full IPL reboot except changing an nvram setting that persistently disables fast-reset for all subsequent reboots. This patch provides a more direct way for the user to force a one-shot full IPL reboot by passing the command line argument 'full' to the reboot command. So the user will be able to tweak the reboot behavior via: $ sudo reboot full # Force a full ipl reboot skipping fast-reset or $ sudo reboot # default reboot path (usually fast-reset) The reboot command passes the un-parsed command argument to the kernel via the 'Reboot' syscall which is then passed on to the arch function pnv_restart(). The patch updates pnv_restart() to handle this cmd-arg and issues opal_cec_reboot2 with OPAL_REBOOT_FULL_IPL to force a full IPL reset.
We're about to introduce an MPIPL reboot type (to take a firmware assisted kdump style thing), and we maybe should have a reboot type to force attempting a fast-reboot, and this makes me think if we should add those in now?
quoted hunk ↗ jump to hunk
Signed-off-by: Vaibhav Jain <redacted> --- arch/powerpc/include/asm/opal-api.h | 1 + arch/powerpc/platforms/powernv/setup.c | 8 +++++++- 2 files changed, 8 insertions(+), 1 deletion(-)diff --git a/arch/powerpc/include/asm/opal-api.h b/arch/powerpc/include/asm/opal-api.h index 8365353330b4..870fb7b239ea 100644 --- a/arch/powerpc/include/asm/opal-api.h +++ b/arch/powerpc/include/asm/opal-api.h@@ -1050,6 +1050,7 @@ enum OpalSysCooling { enum { OPAL_REBOOT_NORMAL = 0, OPAL_REBOOT_PLATFORM_ERROR = 1, + OPAL_REBOOT_FULL_IPL = 2, }; /* Argument to OPAL_PCI_TCE_KILL */diff --git a/arch/powerpc/platforms/powernv/setup.c b/arch/powerpc/platforms/powernv/setup.c index adddde023622..33d2faeacff8 100644 --- a/arch/powerpc/platforms/powernv/setup.c +++ b/arch/powerpc/platforms/powernv/setup.c@@ -224,7 +224,13 @@ static void __noreturn pnv_restart(char *cmd) pnv_prepare_going_down(); while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) { - rc = opal_cec_reboot(); + + /* See if we need to do a full IPL reboot */ + if (cmd && strcmp(cmd, "full") == 0) + rc = opal_cec_reboot2(OPAL_REBOOT_FULL_IPL, NULL); + else + rc = opal_cec_reboot(); +
If the reboot type isn't supported, what should be the behvaiour? Reboot the default way or don't reboot at all? -- Stewart Smith OPAL Architect, IBM.