summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--arch/arm/cpu/armv8/start.S13
-rw-r--r--arch/arm/include/asm/macro.h18
-rw-r--r--arch/arm/include/asm/system.h6
3 files changed, 32 insertions, 5 deletions
diff --git a/arch/arm/cpu/armv8/start.S b/arch/arm/cpu/armv8/start.S
index 9e9c6140cd..b3eef705a5 100644
--- a/arch/arm/cpu/armv8/start.S
+++ b/arch/arm/cpu/armv8/start.S
@@ -127,10 +127,6 @@ pie_fixup_done:
orr x0, x0, #0xf /* SCR_EL3.NS|IRQ|FIQ|EA */
msr scr_el3, x0
msr cptr_el3, xzr /* Enable FP/SIMD */
-#ifdef COUNTER_FREQUENCY
- ldr x0, =COUNTER_FREQUENCY
- msr cntfrq_el0, x0 /* Initialize CNTFRQ */
-#endif
b 0f
2: mrs x1, hcr_el2
tbnz x1, #34, 1f /* HCR_EL2.E2H */
@@ -142,7 +138,14 @@ pie_fixup_done:
mov x0, #3 << 20
msr cpacr_el1, x0 /* Enable FP/SIMD */
0:
- isb
+
+#ifdef COUNTER_FREQUENCY
+ branch_if_not_highest_el x0, 4f
+ ldr x0, =COUNTER_FREQUENCY
+ msr cntfrq_el0, x0 /* Initialize CNTFRQ */
+#endif
+
+4: isb
/*
* Enable SMPEN bit for coherency.
diff --git a/arch/arm/include/asm/macro.h b/arch/arm/include/asm/macro.h
index bb33b4bc89..485310d660 100644
--- a/arch/arm/include/asm/macro.h
+++ b/arch/arm/include/asm/macro.h
@@ -78,6 +78,24 @@ lr .req x30
.endm
/*
+ * Branch if we are not in the highest exception level
+ */
+.macro branch_if_not_highest_el, xreg, label
+ switch_el \xreg, 3f, 2f, 1f
+
+2: mrs \xreg, ID_AA64PFR0_EL1
+ and \xreg, \xreg, #(ID_AA64PFR0_EL1_EL3)
+ cbnz \xreg, \label
+ b 3f
+
+1: mrs \xreg, ID_AA64PFR0_EL1
+ and \xreg, \xreg, #(ID_AA64PFR0_EL1_EL3 | ID_AA64PFR0_EL1_EL2)
+ cbnz \xreg, \label
+
+3:
+.endm
+
+/*
* Branch if current processor is a Cortex-A57 core.
*/
.macro branch_if_a57_core, xreg, a57_label
diff --git a/arch/arm/include/asm/system.h b/arch/arm/include/asm/system.h
index 11fceec4d2..8b3a54e64c 100644
--- a/arch/arm/include/asm/system.h
+++ b/arch/arm/include/asm/system.h
@@ -80,6 +80,12 @@
#define HCR_EL2_HCD_DIS (1 << 29) /* Hypervisor Call disabled */
/*
+ * ID_AA64PFR0_EL1 bits definitions
+ */
+#define ID_AA64PFR0_EL1_EL3 (0xF << 12) /* EL3 implemented */
+#define ID_AA64PFR0_EL1_EL2 (0xF << 8) /* EL2 implemented */
+
+/*
* CPACR_EL1 bits definitions
*/
#define CPACR_EL1_FPEN_EN (3 << 20) /* SIMD and FP instruction enabled */