| Message ID | 20180911030756.19583-1-mikey@neuling.org (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | dd9a8c5a87395b6f05552c3b44e42fdc95760552 |
| Headers | show |
| Series | powerpc/tm: Fix HFSCR bit for no suspend case | expand |
| Context | Check | Description |
|---|---|---|
| snowpatch_ozlabs/apply_patch | success | next/apply_patch Successfully applied |
| snowpatch_ozlabs/checkpatch | success | Test checkpatch on branch next |
| snowpatch_ozlabs/build-ppc64le | success | Test build-ppc64le on branch next |
| snowpatch_ozlabs/build-ppc64be | success | Test build-ppc64be on branch next |
| snowpatch_ozlabs/build-ppc64e | success | Test build-ppc64e on branch next |
| snowpatch_ozlabs/build-ppc32 | success | Test build-ppc32 on branch next |
On 09/11/2018 12:07 AM, Michael Neuling wrote: > Currently on P9N DD2.1 we end up taking infinite TM facility > unavailable exceptions on the first TM usage by userspace. > > In the special case of TM no suspend (P9N DD2.1), Linux is told TM is > off via CPU dt-ftrs but told to (partially) use it via > OPAL_REINIT_CPUS_TM_SUSPEND_DISABLED. So HFSCR[TM] will be off from > dt-ftrs but we need to turn it on for the no suspend case. > > This patch fixes this by enabling HFSCR TM in this case. > > Cc: stable@vger.kernel.org # 4.15+ > Signed-off-by: Michael Neuling <mikey@neuling.org> Tested-by: Breno Leitao <leitao@debian.org>
On Tue, 2018-09-11 at 03:07:56 UTC, Michael Neuling wrote: > Currently on P9N DD2.1 we end up taking infinite TM facility > unavailable exceptions on the first TM usage by userspace. > > In the special case of TM no suspend (P9N DD2.1), Linux is told TM is > off via CPU dt-ftrs but told to (partially) use it via > OPAL_REINIT_CPUS_TM_SUSPEND_DISABLED. So HFSCR[TM] will be off from > dt-ftrs but we need to turn it on for the no suspend case. > > This patch fixes this by enabling HFSCR TM in this case. > > Cc: stable@vger.kernel.org # 4.15+ > Signed-off-by: Michael Neuling <mikey@neuling.org> > Tested-by: Breno Leitao <leitao@debian.org> Applied to powerpc next, thanks. https://git.kernel.org/powerpc/c/dd9a8c5a87395b6f05552c3b44e42f cheers
diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c index 6a501b25dd..faf00222b3 100644 --- a/arch/powerpc/kernel/setup_64.c +++ b/arch/powerpc/kernel/setup_64.c @@ -243,13 +243,19 @@ static void cpu_ready_for_interrupts(void) } /* - * Fixup HFSCR:TM based on CPU features. The bit is set by our - * early asm init because at that point we haven't updated our - * CPU features from firmware and device-tree. Here we have, - * so let's do it. + * Set HFSCR:TM based on CPU features: + * In the special case of TM no suspend (P9N DD2.1), Linux is + * told TM is off via the dt-ftrs but told to (partially) use + * it via OPAL_REINIT_CPUS_TM_SUSPEND_DISABLED. So HFSCR[TM] + * will be off from dt-ftrs but we need to turn it on for the + * no suspend case. */ - if (cpu_has_feature(CPU_FTR_HVMODE) && !cpu_has_feature(CPU_FTR_TM_COMP)) - mtspr(SPRN_HFSCR, mfspr(SPRN_HFSCR) & ~HFSCR_TM); + if (cpu_has_feature(CPU_FTR_HVMODE)) { + if (cpu_has_feature(CPU_FTR_TM_COMP)) + mtspr(SPRN_HFSCR, mfspr(SPRN_HFSCR) | HFSCR_TM); + else + mtspr(SPRN_HFSCR, mfspr(SPRN_HFSCR) & ~HFSCR_TM); + } /* Set IR and DR in PACA MSR */ get_paca()->kernel_msr = MSR_KERNEL;
Currently on P9N DD2.1 we end up taking infinite TM facility unavailable exceptions on the first TM usage by userspace. In the special case of TM no suspend (P9N DD2.1), Linux is told TM is off via CPU dt-ftrs but told to (partially) use it via OPAL_REINIT_CPUS_TM_SUSPEND_DISABLED. So HFSCR[TM] will be off from dt-ftrs but we need to turn it on for the no suspend case. This patch fixes this by enabling HFSCR TM in this case. Cc: stable@vger.kernel.org # 4.15+ Signed-off-by: Michael Neuling <mikey@neuling.org> --- arch/powerpc/kernel/setup_64.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-)