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.
Signed-off-by: Vaibhav Jain <vaib...@linux.ibm.com>
---
Change-log:
v3 -> Re-factored the code to make it more readable [Andrew]
Handle return of OPAL_SUCCESS from cec_reboot variants
[Vasant]
v2 -> Updated the code to handle case when opal_cec_reboot2() is
not supported by opal. [Andrew]
-> Force a call to opal_cec_reboot() is opal_cec_reboot2()
fails or the action verb 'cmd' is not recognized.
---
arch/powerpc/include/asm/opal-api.h | 1 +
arch/powerpc/platforms/powernv/setup.c | 36 +++++++++++++++++++++-----
2 files changed, 31 insertions(+), 6 deletions(-)
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..79fd839faa2d 100644
--- a/arch/powerpc/platforms/powernv/setup.c
+++ b/arch/powerpc/platforms/powernv/setup.c
@@ -219,17 +219,41 @@ static void pnv_prepare_going_down(void)
static void __noreturn pnv_restart(char *cmd)
{
- long rc = OPAL_BUSY;
+ long rc;
pnv_prepare_going_down();
- while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
- rc = opal_cec_reboot();
- if (rc == OPAL_BUSY_EVENT)
- opal_poll_events(NULL);
+ do {
+ if (!cmd)
+ rc = opal_cec_reboot();
+ else if (strcmp(cmd, "full") == 0)
+ rc = opal_cec_reboot2(OPAL_REBOOT_FULL_IPL, NULL);
else
+ rc = OPAL_UNSUPPORTED;
+
+ if (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
+ /* Opal is busy wait for some time and retry */
+ opal_poll_events(NULL);
mdelay(10);
- }
+
+ } else if (cmd && rc) {
+ /* Unknown error while issuing reboot */
+ if (rc == OPAL_UNSUPPORTED)
+ pr_err("Unsupported '%s' reboot.\n", cmd);
+ else
+ pr_err("Unable to issue '%s' reboot. Err=%ld\n",
+ cmd, rc);
+ pr_info("Forcing a cec-reboot\n");
+ cmd = NULL;
+ rc = OPAL_BUSY;
+
+ } else if (rc != OPAL_SUCCESS) {
+ /* Unknown error while issuing cec-reboot */
+ pr_err("Unable to reboot. Err=%ld\n", rc);
+ }
+
+ } while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT);
+
for (;;)
opal_poll_events(NULL);
}
--
2.17.1
