From bbeb9209515989ff47802d4e5d5702178c8e42c4 Mon Sep 17 00:00:00 2001
From: Lucas Stach <l.stach@pengutronix.de>
Date: Tue, 25 Aug 2015 13:52:09 +0100
Subject: [PATCH] ARM: 8422/1: enable imprecise aborts during early kernel
startup
This patch adds imprecise abort enable/disable macros and uses them to
enable imprecise aborts early when starting the kernel.
This helps in tracking down the real cause for such imprecise abort, as
they are handled as soon as they occur. Until now those aborts would
only be enabled when entering the userspace and as a consequence crash
the first userspace process if any abort had been raised during kernel
startup.
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
---
arch/arm/include/asm/irqflags.h | 10 ++++++++++
arch/arm/kernel/smp.c | 1 +
arch/arm/mm/mmu.c | 3 +++
3 files changed, 14 insertions(+)
diff --git a/arch/arm/include/asm/irqflags.h b/arch/arm/include/asm/irqflags.h
index 43908146a5cf..e6b70d9d084e 100644
--- a/arch/arm/include/asm/irqflags.h
+++ b/arch/arm/include/asm/irqflags.h
@@ -54,6 +54,14 @@ static inline void arch_local_irq_disable(void)
#define local_fiq_enable() __asm__("cpsie f @ __stf" : : : "memory", "cc")
#define local_fiq_disable() __asm__("cpsid f @ __clf" : : : "memory", "cc")
+
+#ifndef CONFIG_CPU_V7M
+#define local_abt_enable() __asm__("cpsie a @ __sta" : : : "memory", "cc")
+#define local_abt_disable() __asm__("cpsid a @ __cla" : : : "memory", "cc")
+#else
+#define local_abt_enable() do { } while (0)
+#define local_abt_disable() do { } while (0)
+#endif
#else
/*
@@ -136,6 +144,8 @@ static inline void arch_local_irq_disable(void)
: "memory", "cc"); \
})
+#define local_abt_enable() do { } while (0)
+#define local_abt_disable() do { } while (0)
#endif
/*
diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
index 48185a773852..36045e8ced01 100644
--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c
@@ -400,6 +400,7 @@ asmlinkage void secondary_start_kernel(void)
local_irq_enable();
local_fiq_enable();
+ local_abt_enable();
/*
* OK, it's off to the idle thread for us
diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
index 7cd15143a507..f65a6f344b6d 100644
--- a/arch/arm/mm/mmu.c
+++ b/arch/arm/mm/mmu.c
@@ -1363,6 +1363,9 @@ static void __init devicemaps_init(const struct machine_desc *mdesc)
*/
local_flush_tlb_all();
flush_cache_all();
+
+ /* Enable asynchronous aborts */
+ local_abt_enable();
}
static void __init kmap_init(void)
--
2.34.1