From ca4a6f87150b2cec4feab2610ef7a0d6d7fcd800 Mon Sep 17 00:00:00 2001 From: Thomas Petazzoni Date: Mon, 17 Feb 2014 15:23:24 +0100 Subject: [PATCH] ARM: mvebu: add workaround for data abort issue on Armada 375 Early versions of Armada 375 SoC have a bug where the BootROM leaves an external data abort pending. The kernel is hit by this data abort as soon as it enters userspace, because it unmasks the data aborts at this moment. We register a custom abort handler below to ignore the first data abort to work around this problem. Signed-off-by: Thomas Petazzoni Signed-off-by: Jason Cooper --- arch/arm/mach-mvebu/board-v7.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) diff --git a/arch/arm/mach-mvebu/board-v7.c b/arch/arm/mach-mvebu/board-v7.c index a6234bfc1d69..087668c7d46a 100644 --- a/arch/arm/mach-mvebu/board-v7.c +++ b/arch/arm/mach-mvebu/board-v7.c @@ -31,6 +31,27 @@ #include "coherency.h" #include "mvebu-soc-id.h" +/* + * Early versions of Armada 375 SoC have a bug where the BootROM + * leaves an external data abort pending. The kernel is hit by this + * data abort as soon as it enters userspace, because it unmasks the + * data aborts at this moment. We register a custom abort handler + * below to ignore the first data abort to work around this + * problem. + */ +static int armada_375_external_abort_wa(unsigned long addr, unsigned int fsr, + struct pt_regs *regs) +{ + static int ignore_first; + + if (!ignore_first && fsr == 0x1406) { + ignore_first = 1; + return 0; + } + + return 1; +} + static void __init mvebu_timer_and_clk_init(void) { of_clk_init(NULL); @@ -40,6 +61,10 @@ static void __init mvebu_timer_and_clk_init(void) #ifdef CONFIG_CACHE_L2X0 l2x0_of_init(0, ~0UL); #endif + + if (of_machine_is_compatible("marvell,armada375")) + hook_fault_code(16 + 6, armada_375_external_abort_wa, SIGBUS, 0, + "imprecise external abort"); } static void __init i2c_quirk(void) -- 2.39.5