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-rw-r--r--arch/arm/kernel/head.S21
1 files changed, 20 insertions, 1 deletions
diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S
index 2c7cc1e03473..476de57dcef2 100644
--- a/arch/arm/kernel/head.S
+++ b/arch/arm/kernel/head.S
@@ -487,7 +487,26 @@ __fixup_smp:
 	mrc	p15, 0, r0, c0, c0, 5	@ read MPIDR
 	and	r0, r0, #0xc0000000	@ multiprocessing extensions and
 	teq	r0, #0x80000000		@ not part of a uniprocessor system?
-	moveq	pc, lr			@ yes, assume SMP
+	bne    __fixup_smp_on_up	@ no, assume UP
+
+	@ Core indicates it is SMP. Check for Aegis SOC where a single
+	@ Cortex-A9 CPU is present but SMP operations fault.
+	mov	r4, #0x41000000
+	orr	r4, r4, #0x0000c000
+	orr	r4, r4, #0x00000090
+	teq	r3, r4			@ Check for ARM Cortex-A9
+	movne	pc, lr			@ Not ARM Cortex-A9,
+
+	@ If a future SoC *does* use 0x0 as the PERIPH_BASE, then the
+	@ below address check will need to be #ifdef'd or equivalent
+	@ for the Aegis platform.
+	mrc	p15, 4, r0, c15, c0	@ get SCU base address
+	teq	r0, #0x0		@ '0' on actual UP A9 hardware
+	beq	__fixup_smp_on_up	@ So its an A9 UP
+	ldr	r0, [r0, #4]		@ read SCU Config
+	and	r0, r0, #0x3		@ number of CPUs
+	teq	r0, #0x0		@ is 1?
+	movne	pc, lr
 
 __fixup_smp_on_up:
 	adr	r0, 1f