[PATCH V2] powerpc/TM: Disable/Enable TM looking at the ibm, pa-features device tree entry

Aneesh Kumar K.V aneesh.kumar at linux.vnet.ibm.com
Mon Nov 3 01:32:42 AEDT 2014


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 <aneesh.kumar at linux.vnet.ibm.com>
---
Changes from V1:
* rebase to latest linus

 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 099f27e6d1b0..3e22930f15d1 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, const unsigned char *ftrs,
-- 
2.1.0



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