| Message ID | 151351242343.5903.13165313011722996463.stgit@jupiter.in.ibm.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | opal/xstop: Use nvram option to enable/disable sw checkstop. | expand |
On Sun, Dec 17, 2017 at 11:14 PM, Mahesh J Salgaonkar <mahesh@linux.vnet.ibm.com> wrote: > From: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> > > Add a mechanism to enable/disable sw checkstop by looking at nvram option > opal-sw-xstop=<enable/disable>. > > For now this patch disables the sw checkstop trigger unless explicitly > enabled through nvram option 'opal-sw-xstop=enable' for p9. This will allow > an opportunity to get host kernel in panic path or xmon for unrecoverable > HMIs or MCE, to be able to debug the issue effectively. > > To enable sw checkstop in opal issue following command: > > # nvram -p ibm,skiboot --update-config opal-sw-xstop=enable > > NOTE: This is a workaround patch to disable sw checkstop by default to gain > control in host kernel for better checkstop debugging. Once we have most of > the checkstop issues stabilized/resolved, revisit this patch to enable sw > checkstop by default for p9. > > For p8 platform it will remain enabled by default unless explicitly disabled. > > To disable sw checkstop on p8 issue following command: > > # nvram -p ibm,skiboot --update-config opal-sw-xstop=disable > > Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> > --- > hw/xscom.c | 26 ++++++++++++++++++++++++++ > 1 file changed, 26 insertions(+) > > diff --git a/hw/xscom.c b/hw/xscom.c > index de5a27e..7b530a9 100644 > --- a/hw/xscom.c > +++ b/hw/xscom.c > @@ -24,6 +24,7 @@ > #include <errorlog.h> > #include <opal-api.h> > #include <timebase.h> > +#include <nvram.h> > > /* Mask of bits to clear in HMER before an access */ > #define HMER_CLR_MASK (~(SPR_HMER_XSCOM_FAIL | \ > @@ -827,6 +828,31 @@ int64_t xscom_trigger_xstop(void) > { > int rc = OPAL_UNSUPPORTED; > > + /* > + * Workaround until we iron out all checkstop issues at present. > + * > + * For p9: > + * By default do not trigger sw checkstop unless explicitly enabled > + * through nvram option 'opal-sw-xstop=enable'. > + * > + * For p8: > + * Keep it enabled by default unless explicitly disabled. > + * > + * NOTE: Once all checkstop issues are resolved/stabilized reverse > + * the logic to enable sw checkstop by default on p9. > + */ > + switch (proc_gen) { > + case proc_gen_p8: > + if (nvram_query_eq("opal-sw-xstop", "disable")) > + return rc; > + break; > + case proc_gen_p9: > + default: > + if (!nvram_query_eq("opal-sw-xstop", "enable")) > + return rc; > + break; > + } Can we get a prlog to indicate that we did not checkstop? I think it will be useful when we debug. Ideally the OS will crash/reboot and tell us from the stack > + > if (xstop_xscom.addr) > rc = xscom_writeme(xstop_xscom.addr, > PPC_BIT(xstop_xscom.fir_bit)); > Reviewed-by: Balbir Singh <bsingharora@gmail.com>
diff --git a/hw/xscom.c b/hw/xscom.c index de5a27e..7b530a9 100644 --- a/hw/xscom.c +++ b/hw/xscom.c @@ -24,6 +24,7 @@ #include <errorlog.h> #include <opal-api.h> #include <timebase.h> +#include <nvram.h> /* Mask of bits to clear in HMER before an access */ #define HMER_CLR_MASK (~(SPR_HMER_XSCOM_FAIL | \ @@ -827,6 +828,31 @@ int64_t xscom_trigger_xstop(void) { int rc = OPAL_UNSUPPORTED; + /* + * Workaround until we iron out all checkstop issues at present. + * + * For p9: + * By default do not trigger sw checkstop unless explicitly enabled + * through nvram option 'opal-sw-xstop=enable'. + * + * For p8: + * Keep it enabled by default unless explicitly disabled. + * + * NOTE: Once all checkstop issues are resolved/stabilized reverse + * the logic to enable sw checkstop by default on p9. + */ + switch (proc_gen) { + case proc_gen_p8: + if (nvram_query_eq("opal-sw-xstop", "disable")) + return rc; + break; + case proc_gen_p9: + default: + if (!nvram_query_eq("opal-sw-xstop", "enable")) + return rc; + break; + } + if (xstop_xscom.addr) rc = xscom_writeme(xstop_xscom.addr, PPC_BIT(xstop_xscom.fir_bit));