diff options
author | Daniel Thompson <daniel.thompson@linaro.org> | 2016-08-19 17:13:09 +0100 |
---|---|---|
committer | Marc Zyngier <marc.zyngier@arm.com> | 2016-09-12 19:46:19 +0100 |
commit | 91ef84428a86b75a52e15c6fe4f56b446ba75f93 (patch) | |
tree | 46066d44e3ddccef1b4d0056955eb59ffc67cf54 /arch/arm64/include/asm | |
parent | 04c8b0f82c7d5a9a1c296eef914ae3bb820bcb85 (diff) | |
download | linux-91ef84428a86b75a52e15c6fe4f56b446ba75f93.tar.gz |
irqchip/gic-v3: Reset BPR during initialization
Currently, when running on FVP, CPU 0 boots up with its BPR changed from
the reset value. This renders it impossible to (preemptively) prioritize
interrupts on CPU 0.
This is harmless on normal systems since Linux typically does not
support preemptive interrupts. It does however cause problems in
systems with additional changes (such as patches for NMI simulation).
Many thanks to Andrew Thoelke for suggesting the BPR as having the
potential to harm preemption.
Suggested-by: Andrew Thoelke <andrew.thoelke@arm.com>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Diffstat (limited to 'arch/arm64/include/asm')
-rw-r--r-- | arch/arm64/include/asm/arch_gicv3.h | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/arch_gicv3.h b/arch/arm64/include/asm/arch_gicv3.h index 8ec88e5b290f..fc2a0cb47b2c 100644 --- a/arch/arm64/include/asm/arch_gicv3.h +++ b/arch/arm64/include/asm/arch_gicv3.h @@ -28,6 +28,7 @@ #define ICC_CTLR_EL1 sys_reg(3, 0, 12, 12, 4) #define ICC_SRE_EL1 sys_reg(3, 0, 12, 12, 5) #define ICC_GRPEN1_EL1 sys_reg(3, 0, 12, 12, 7) +#define ICC_BPR1_EL1 sys_reg(3, 0, 12, 12, 3) #define ICC_SRE_EL2 sys_reg(3, 4, 12, 9, 5) @@ -165,6 +166,11 @@ static inline void gic_write_sre(u32 val) isb(); } +static inline void gic_write_bpr1(u32 val) +{ + asm volatile("msr_s " __stringify(ICC_BPR1_EL1) ", %0" : : "r" (val)); +} + #define gic_read_typer(c) readq_relaxed(c) #define gic_write_irouter(v, c) writeq_relaxed(v, c) |