diff options
Diffstat (limited to '0029-ARM-non-sec-reset-CNTVOFF-to-zero.patch')
| -rw-r--r-- | 0029-ARM-non-sec-reset-CNTVOFF-to-zero.patch | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/0029-ARM-non-sec-reset-CNTVOFF-to-zero.patch b/0029-ARM-non-sec-reset-CNTVOFF-to-zero.patch new file mode 100644 index 0000000..5b129d3 --- /dev/null +++ b/0029-ARM-non-sec-reset-CNTVOFF-to-zero.patch @@ -0,0 +1,50 @@ +From 2e19eb7de158a26c335d8820becaf859602dd401 Mon Sep 17 00:00:00 2001 +From: Marc Zyngier <marc.zyngier@arm.com> +Date: Sat, 26 Apr 2014 13:17:04 +0100 +Subject: [PATCH 29/36] ARM: non-sec: reset CNTVOFF to zero + +Before switching to non-secure, make sure that CNTVOFF is set +to zero on all CPUs. Otherwise, kernel running in non-secure +without HYP enabled (hence using virtual timers) may observe +timers that are not synchronized, effectively seeing time +going backward... + +Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> +--- + arch/arm/cpu/armv7/nonsec_virt.S | 9 ++++++++- + 1 file changed, 8 insertions(+), 1 deletion(-) + +diff --git a/arch/arm/cpu/armv7/nonsec_virt.S b/arch/arm/cpu/armv7/nonsec_virt.S +index 12de5c2..b5c946f 100644 +--- a/arch/arm/cpu/armv7/nonsec_virt.S ++++ b/arch/arm/cpu/armv7/nonsec_virt.S +@@ -38,10 +38,10 @@ _secure_monitor: + bic r1, r1, #0x4e @ clear IRQ, FIQ, EA, nET bits + orr r1, r1, #0x31 @ enable NS, AW, FW bits + +-#ifdef CONFIG_ARMV7_VIRT + mrc p15, 0, r0, c0, c1, 1 @ read ID_PFR1 + and r0, r0, #CPUID_ARM_VIRT_MASK @ mask virtualization bits + cmp r0, #(1 << CPUID_ARM_VIRT_SHIFT) ++#ifdef CONFIG_ARMV7_VIRT + orreq r1, r1, #0x100 @ allow HVC instruction + #endif + +@@ -52,7 +52,14 @@ _secure_monitor: + mrceq p15, 0, r0, c12, c0, 1 @ get MVBAR value + mcreq p15, 4, r0, c12, c0, 0 @ write HVBAR + #endif ++ bne 1f + ++ @ Reset CNTVOFF to 0 before leaving monitor mode ++ mrc p15, 0, r0, c0, c1, 1 @ read ID_PFR1 ++ ands r0, r0, #CPUID_ARM_GENTIMER_MASK @ test arch timer bits ++ movne r0, #0 ++ mcrrne p15, 4, r0, r0, c14 @ Reset CNTVOFF to zero ++1: + movs pc, lr @ return to non-secure SVC + + _hyp_trap: +-- +1.9.0 + |