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-rw-r--r--arch/arm64/kernel/head.S5
-rw-r--r--arch/arm64/mm/proc-macros.S12
-rw-r--r--arch/arm64/mm/proc.S4
3 files changed, 19 insertions, 2 deletions
diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
index ffe9c2b6431b..917d98108b3f 100644
--- a/arch/arm64/kernel/head.S
+++ b/arch/arm64/kernel/head.S
@@ -514,9 +514,14 @@ CPU_LE( movk x0, #0x30d0, lsl #16 ) // Clear EE and E0E on LE systems
#endif
/* EL2 debug */
+ mrs x0, id_aa64dfr0_el1 // Check ID_AA64DFR0_EL1 PMUVer
+ sbfx x0, x0, #8, #4
+ cmp x0, #1
+ b.lt 4f // Skip if no PMU present
mrs x0, pmcr_el0 // Disable debug access traps
ubfx x0, x0, #11, #5 // to EL2 and allow access to
msr mdcr_el2, x0 // all PMU counters from EL1
+4:
/* Stage-2 translation */
msr vttbr_el2, xzr
diff --git a/arch/arm64/mm/proc-macros.S b/arch/arm64/mm/proc-macros.S
index 146bd99a7532..e6a30e1268a8 100644
--- a/arch/arm64/mm/proc-macros.S
+++ b/arch/arm64/mm/proc-macros.S
@@ -84,3 +84,15 @@
b.lo 9998b
dsb \domain
.endm
+
+/*
+ * reset_pmuserenr_el0 - reset PMUSERENR_EL0 if PMUv3 present
+ */
+ .macro reset_pmuserenr_el0, tmpreg
+ mrs \tmpreg, id_aa64dfr0_el1 // Check ID_AA64DFR0_EL1 PMUVer
+ sbfx \tmpreg, \tmpreg, #8, #4
+ cmp \tmpreg, #1 // Skip if no PMU present
+ b.lt 9000f
+ msr pmuserenr_el0, xzr // Disable PMU access from EL0
+9000:
+ .endm
diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S
index a3d867e723b4..c164d2cb35c0 100644
--- a/arch/arm64/mm/proc.S
+++ b/arch/arm64/mm/proc.S
@@ -117,7 +117,7 @@ ENTRY(cpu_do_resume)
*/
ubfx x11, x11, #1, #1
msr oslar_el1, x11
- msr pmuserenr_el0, xzr // Disable PMU access from EL0
+ reset_pmuserenr_el0 x0 // Disable PMU access from EL0
mov x0, x12
dsb nsh // Make sure local tlb invalidation completed
isb
@@ -154,7 +154,7 @@ ENTRY(__cpu_setup)
msr cpacr_el1, x0 // Enable FP/ASIMD
mov x0, #1 << 12 // Reset mdscr_el1 and disable
msr mdscr_el1, x0 // access to the DCC from EL0
- msr pmuserenr_el0, xzr // Disable PMU access from EL0
+ reset_pmuserenr_el0 x0 // Disable PMU access from EL0
/*
* Memory region attributes for LPAE:
*