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| author | Michael Ellerman <mpe@ellerman.id.au> | 2017-10-12 21:17:18 +1100 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2017-10-21 09:33:05 +1100 |
| commit | 54820530c5faa9fd78e1c08cb6449100b1a19157 (patch) | |
| tree | b7b605fd74c9435143d6c3464d4c829e95ea8141 /arch/powerpc/platforms | |
| parent | cba6ac4869e45cc93ac5497024d1d49576e82666 (diff) | |
| download | linux-54820530c5faa9fd78e1c08cb6449100b1a19157.tar.gz linux-54820530c5faa9fd78e1c08cb6449100b1a19157.tar.bz2 linux-54820530c5faa9fd78e1c08cb6449100b1a19157.zip | |
powerpc/powernv: Enable TM without suspend if possible
Some Power9 revisions can run in a mode where TM operates without
suspended state. If we find ourself on a CPU that might be in this
mode, we query OPAL to check, and if so we reenable TM in CPU
features, and enable a new user feature to signal to userspace that we
are in this mode.
We do not enable the "normal" user feature, PPC_FEATURE2_HTM, but we
do enable PPC_FEATURE2_HTM_NOSC because that indicates to userspace
that the kernel will abort transactions on syscall entry, which is
true regardless of the suspend mode.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/platforms')
| -rw-r--r-- | arch/powerpc/platforms/powernv/setup.c | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/powernv/setup.c b/arch/powerpc/platforms/powernv/setup.c index cf52d53da460..d23f148a11f0 100644 --- a/arch/powerpc/platforms/powernv/setup.c +++ b/arch/powerpc/platforms/powernv/setup.c @@ -36,6 +36,7 @@ #include <asm/opal.h> #include <asm/kexec.h> #include <asm/smp.h> +#include <asm/tm.h> #include "powernv.h" @@ -304,6 +305,28 @@ static int __init pnv_probe(void) return 1; } +#ifdef CONFIG_PPC_TRANSACTIONAL_MEM +void __init pnv_tm_init(void) +{ + if (!firmware_has_feature(FW_FEATURE_OPAL) || + !pvr_version_is(PVR_POWER9) || + early_cpu_has_feature(CPU_FTR_TM)) + return; + + if (opal_reinit_cpus(OPAL_REINIT_CPUS_TM_SUSPEND_DISABLED) != OPAL_SUCCESS) + return; + + pr_info("Enabling TM (Transactional Memory) with Suspend Disabled\n"); + cur_cpu_spec->cpu_features |= CPU_FTR_TM; + /* Make sure "normal" HTM is off (it should be) */ + cur_cpu_spec->cpu_user_features2 &= ~PPC_FEATURE2_HTM; + /* Turn on no suspend mode, and HTM no SC */ + cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_HTM_NO_SUSPEND | \ + PPC_FEATURE2_HTM_NOSC; + tm_suspend_disabled = true; +} +#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */ + /* * Returns the cpu frequency for 'cpu' in Hz. This is used by * /proc/cpuinfo |