[PATCH stable v4.9 22/35] powerpc/powernv: Query firmware for count cache flush settings

Michael Ellerman mpe at ellerman.id.au
Thu Apr 11 21:46:17 AEST 2019


commit 99d54754d3d5f896a8f616b0b6520662bc99d66b upstream.

Look for fw-features properties to determine the appropriate settings
for the count cache flush, and then call the generic powerpc code to
set it up based on the security feature flags.

Signed-off-by: Michael Ellerman <mpe at ellerman.id.au>
---
 arch/powerpc/platforms/powernv/setup.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/arch/powerpc/platforms/powernv/setup.c b/arch/powerpc/platforms/powernv/setup.c
index 17203abf38e8..365e2b620201 100644
--- a/arch/powerpc/platforms/powernv/setup.c
+++ b/arch/powerpc/platforms/powernv/setup.c
@@ -77,6 +77,12 @@ static void init_fw_feat_flags(struct device_node *np)
 	if (fw_feature_is("enabled", "fw-count-cache-disabled", np))
 		security_ftr_set(SEC_FTR_COUNT_CACHE_DISABLED);
 
+	if (fw_feature_is("enabled", "fw-count-cache-flush-bcctr2,0,0", np))
+		security_ftr_set(SEC_FTR_BCCTR_FLUSH_ASSIST);
+
+	if (fw_feature_is("enabled", "needs-count-cache-flush-on-context-switch", np))
+		security_ftr_set(SEC_FTR_FLUSH_COUNT_CACHE);
+
 	/*
 	 * The features below are enabled by default, so we instead look to see
 	 * if firmware has *disabled* them, and clear them if so.
@@ -123,6 +129,7 @@ static void pnv_setup_rfi_flush(void)
 		  security_ftr_enabled(SEC_FTR_L1D_FLUSH_HV));
 
 	setup_rfi_flush(type, enable);
+	setup_count_cache_flush();
 }
 
 static void __init pnv_setup_arch(void)
-- 
2.20.1



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