ARMv7: start.S: stay in HYP mode if u-boot is entered in it
The KVM and Xen hypervisors for the Cortex-A15 virtualization
implementation need to be entered in HYP mode. Should the primary
board firmware already enter HYP mode (Calxeda firmware does that),
we should not deliberately drop back to SVC mode.
Since U-boot does not use the MMU, running in HYP mode is just fine.
Signed-off-by: Andre Przywara <andre.przywara@linaro.org>
diff --git a/arch/arm/cpu/armv7/start.S b/arch/arm/cpu/armv7/start.S
index 61da7ac..5feae7a 100644
--- a/arch/arm/cpu/armv7/start.S
+++ b/arch/arm/cpu/armv7/start.S
@@ -130,11 +130,15 @@
reset:
bl save_boot_params
/*
- * set the cpu to SVC32 mode
+ * disable interrupts (FIQ and IRQ), also set the cpu to SVC32 mode,
+ * except if in HYP mode already
*/
mrs r0, cpsr
- bic r0, r0, #0x1f
- orr r0, r0, #0xd3
+ and r1, r0, #0x1f @ mask mode bits
+ teq r1, #0x1a @ test for HYP mode
+ bicne r0, r0, #0x1f @ clear all mode bits
+ orrne r0, r0, #0x13 @ set SVC mode
+ orr r0, r0, #0xc0 @ disable FIQ and IRQ
msr cpsr,r0
/*