From: Vladimir Murzin vladimir.murzin@arm.com
[ Upstream commit d410a8a49e3e00e07d43037e90f776d522b25a6a ]
To access PRBARn, where n is referenced as a binary number:
MRC p15, 0, <Rt>, c6, c8+n[3:1], 4*n[0] ; Read PRBARn into Rt MCR p15, 0, <Rt>, c6, c8+n[3:1], 4*n[0] ; Write Rt into PRBARn
To access PRLARn, where n is referenced as a binary number:
MRC p15, 0, <Rt>, c6, c8+n[3:1], 4*n[0]+1 ; Read PRLARn into Rt MCR p15, 0, <Rt>, c6, c8+n[3:1], 4*n[0]+1 ; Write Rt into PRLARn
For PR{B,L}AR4, n is 4, n[0] is 0, n[3:1] is 2, while current encoding done with n[0] set to 1 which is wrong. Use proper encoding instead.
Fixes: 046835b4aa22b9ab6aa0bb274e3b71047c4b887d ("ARM: 8757/1: NOMMU: Support PMSAv8 MPU") 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 | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/arm/kernel/head-nommu.S b/arch/arm/kernel/head-nommu.S index 326a97aa3ea0..22efcf48604c 100644 --- a/arch/arm/kernel/head-nommu.S +++ b/arch/arm/kernel/head-nommu.S @@ -441,8 +441,8 @@ M_CLASS(str r6, [r12, #PMSAv8_RLAR_A(3)]) str r5, [r12, #PMSAv8_RBAR_A(0)] str r6, [r12, #PMSAv8_RLAR_A(0)] #else - mcr p15, 0, r5, c6, c10, 1 @ PRBAR4 - mcr p15, 0, r6, c6, c10, 2 @ PRLAR4 + mcr p15, 0, r5, c6, c10, 0 @ PRBAR4 + mcr p15, 0, r6, c6, c10, 1 @ PRLAR4 #endif #endif ret lr