Re: [RFC PATCH 10/10] PPC: BOOK3S: Disable/Enable TM looking at the ibm,pa-features device tree entry
On 01/28/2014 05:44 PM, Aneesh Kumar K.V wrote: Runtime disable transactional memory feature looking at pa-features device tree entry. We need to do this so that we can run a kernel built with TM config in PR mode. For PR guest we provide a device tree entry with TM feature disabled in pa-features Signed-off-by: Aneesh Kumar K.V We need to be able to run kernels without this patch, so better fix TM for good - worst case by always aborting transactions. Alex --- arch/powerpc/kernel/prom.c | 5 + 1 file changed, 5 insertions(+) diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c index fa0ad8aafbcc..de8c2caf1024 100644 --- a/arch/powerpc/kernel/prom.c +++ b/arch/powerpc/kernel/prom.c @@ -160,6 +160,11 @@ static struct ibm_pa_feature { {CPU_FTR_NODSISRALIGN, 0, 0,1, 1, 1}, {0, MMU_FTR_CI_LARGE_PAGE, 0, 1, 2, 0}, {CPU_FTR_REAL_LE, PPC_FEATURE_TRUE_LE, 5, 0, 0}, + /* +* We should use CPU_FTR_TM_COMP so that if we disable TM, it won't get +* enabled via device tree +*/ + {CPU_FTR_TM_COMP, 0, 0, 22, 0, 0}, }; static void __init scan_features(unsigned long node, unsigned char *ftrs, ___ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
[RFC PATCH 10/10] PPC: BOOK3S: Disable/Enable TM looking at the ibm, pa-features device tree entry
Runtime disable transactional memory feature looking at pa-features device tree entry. We need to do this so that we can run a kernel built with TM config in PR mode. For PR guest we provide a device tree entry with TM feature disabled in pa-features Signed-off-by: Aneesh Kumar K.V --- arch/powerpc/kernel/prom.c | 5 + 1 file changed, 5 insertions(+) diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c index fa0ad8aafbcc..de8c2caf1024 100644 --- a/arch/powerpc/kernel/prom.c +++ b/arch/powerpc/kernel/prom.c @@ -160,6 +160,11 @@ static struct ibm_pa_feature { {CPU_FTR_NODSISRALIGN, 0, 0,1, 1, 1}, {0, MMU_FTR_CI_LARGE_PAGE, 0, 1, 2, 0}, {CPU_FTR_REAL_LE, PPC_FEATURE_TRUE_LE, 5, 0, 0}, + /* +* We should use CPU_FTR_TM_COMP so that if we disable TM, it won't get +* enabled via device tree +*/ + {CPU_FTR_TM_COMP, 0, 0, 22, 0, 0}, }; static void __init scan_features(unsigned long node, unsigned char *ftrs, -- 1.8.5.3 ___ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev