From: Tigran Tadevosyan tigran.tadevosyan@arm.com
[ Upstream commit c3143967807adb1357c36b68a7563fc0c4e1f615 ]
When CONFIG_ARM_MPU is not defined, the base address of v7M SCB register is not initialized with correct value. This prevents enabling I/D caches when the L1 cache poilcy is applied in kernel.
Fixes: 3c24121039c9da14692eb48f6e39565b28c0f3cf ("ARM: 8756/1: NOMMU: Postpone MPU activation till __after_proc_init") Signed-off-by: Tigran Tadevosyan tigran.tadevosyan@arm.com Signed-off-by: Vladimir Murzin vladimir.murzin@arm.com Signed-off-by: Russell King rmk+kernel@armlinux.org.uk Signed-off-by: Sasha Levin sashal@kernel.org --- arch/arm/kernel/head-nommu.S | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/arm/kernel/head-nommu.S b/arch/arm/kernel/head-nommu.S index ec29de250076..cab89479d15e 100644 --- a/arch/arm/kernel/head-nommu.S +++ b/arch/arm/kernel/head-nommu.S @@ -133,9 +133,9 @@ __secondary_data: */ .text __after_proc_init: -#ifdef CONFIG_ARM_MPU M_CLASS(movw r12, #:lower16:BASEADDR_V7M_SCB) M_CLASS(movt r12, #:upper16:BASEADDR_V7M_SCB) +#ifdef CONFIG_ARM_MPU M_CLASS(ldr r3, [r12, 0x50]) AR_CLASS(mrc p15, 0, r3, c0, c1, 4) @ Read ID_MMFR0 and r3, r3, #(MMFR0_PMSA) @ PMSA field