[PATCH v4 09/22] arm64: capabilities: Split the processing of errata work arounds

Suzuki K Poulose suzuki.poulose at arm.com
Tue Mar 13 04:51:07 PDT 2018


Right now we run through the errata workarounds check on all boot
active CPUs, with SCOPE_ALL. This wouldn't help for detecting erratum
workarounds with a SYSTEM_SCOPE. There are none yet, but we plan to
introduce some: let us clean this up so that such workarounds can be
detected and enabled correctly.

So, we run the checks with SCOPE_LOCAL_CPU on all CPUs and SCOPE_SYSTEM
checks are run only once after all the boot time CPUs are active.

Reviewed-by: Dave Martin <dave.martin at arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose at arm.com>
---
 arch/arm64/kernel/cpufeature.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index 4386675af189..9f2152858c05 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -557,7 +557,7 @@ void __init init_cpu_features(struct cpuinfo_arm64 *info)
 	 * Run the errata work around checks on the boot CPU, once we have
 	 * initialised the cpu feature infrastructure.
 	 */
-	update_cpu_capabilities(arm64_errata, SCOPE_ALL,
+	update_cpu_capabilities(arm64_errata, SCOPE_LOCAL_CPU,
 				"enabling workaround for");
 }
 
@@ -1445,7 +1445,7 @@ void check_local_cpu_capabilities(void)
 	 * advertised capabilities.
 	 */
 	if (!sys_caps_initialised)
-		update_cpu_capabilities(arm64_errata, SCOPE_ALL,
+		update_cpu_capabilities(arm64_errata, SCOPE_LOCAL_CPU,
 					"enabling workaround for");
 	else
 		verify_local_cpu_capabilities();
@@ -1473,6 +1473,8 @@ void __init setup_cpu_features(void)
 
 	/* Set the CPU feature capabilies */
 	update_cpu_capabilities(arm64_features, SCOPE_ALL, "detected:");
+	update_cpu_capabilities(arm64_errata, SCOPE_SYSTEM,
+				"enabling workaround for");
 	enable_cpu_capabilities(arm64_features, SCOPE_ALL);
 	enable_cpu_capabilities(arm64_errata, SCOPE_ALL);
 	mark_const_caps_ready();
-- 
2.14.3




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