diff options
Diffstat (limited to 'arch/arm')
| -rw-r--r-- | arch/arm/kernel/head.S | 21 |
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 |