Re: [PATCH] PPC: BOOK3S: Disable/Enable TM looking at the ibm, pa-features device tree entry
From: Michael Neuling <hidden>
Date: 2014-05-01 05:01:40
Aneesh Kumar K.V [off-list ref] wrote:
Runtime disable transactional memory feature looking at pa-features device tree entry. This provides a mechanism to disable TM on P8 systems.
What are we actually achieving with this?
quoted hunk ↗ jump to hunk
Signed-off-by: Aneesh Kumar K.V <redacted> --- 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 668aa4791fd7..537bd7e7db0b 100644 --- a/arch/powerpc/kernel/prom.c +++ b/arch/powerpc/kernel/prom.c@@ -161,6 +161,11 @@ 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},
What does this do to guests? Will it turn TM unavailable into an illegal instruction? Mikey
}; static void __init scan_features(unsigned long node, unsigned char *ftrs, -- 1.9.1 _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev