From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <zajec5@gmail.com>
Date: Tue, 8 Mar 2016 09:03:21 +0100
Subject: [PATCH] Revert "ARM: BCM5301X: remove workaround imprecise abort
 fault handler"
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This reverts commit 937b12306ea79044c86f2e69b3061c7279245825.

It seems imprecise external abort (0x1406) can be still happen on
BCM4709 during PCI initialization.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
---

--- a/arch/arm/mach-bcm/bcm_5301x.c
+++ b/arch/arm/mach-bcm/bcm_5301x.c
@@ -9,6 +9,40 @@
 #include <asm/hardware/cache-l2x0.h>
 
 #include <asm/mach/arch.h>
+#include <asm/siginfo.h>
+#include <asm/signal.h>
+
+
+static bool first_fault = true;
+
+static int bcm5301x_abort_handler(unsigned long addr, unsigned int fsr,
+				 struct pt_regs *regs)
+{
+	if ((fsr == 0x1406 || fsr == 0x1c06) && first_fault) {
+		first_fault = false;
+
+		/*
+		 * These faults with codes 0x1406 (BCM4709) or 0x1c06 happens
+		 * for no good reason, possibly left over from the CFE boot
+		 * loader.
+		 */
+		pr_warn("External imprecise Data abort at addr=%#lx, fsr=%#x ignored.\n",
+			addr, fsr);
+
+		/* Returning non-zero causes fault display and panic */
+		return 0;
+	}
+
+	/* Others should cause a fault */
+	return 1;
+}
+
+static void __init bcm5301x_init_early(void)
+{
+	/* Install our hook */
+	hook_fault_code(16 + 6, bcm5301x_abort_handler, SIGBUS, BUS_OBJERR,
+			"imprecise external abort");
+}
 
 static const char *const bcm5301x_dt_compat[] __initconst = {
 	"brcm,bcm4708",
@@ -18,5 +52,6 @@ static const char *const bcm5301x_dt_com
 DT_MACHINE_START(BCM5301X, "BCM5301X")
 	.l2c_aux_val	= 0,
 	.l2c_aux_mask	= ~0,
+	.init_early	= bcm5301x_init_early,
 	.dt_compat	= bcm5301x_dt_compat,
 MACHINE_END