From f1117fcf87966dfb5b1d9faf78496ba779975032 Mon Sep 17 00:00:00 2001
From: Michael Gernoth <michael@gernoth.net>
Date: Mon, 7 Dec 2015 02:06:07 +0100
Subject: arm/traps: get full DIV instruction in thumb mode

Change-Id: Ie60d2124d7835e85f03008d3dfe259b70490b4f2
---
 arch/arm/kernel/traps.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c
index 56b2715..599ea93 100644
--- a/arch/arm/kernel/traps.c
+++ b/arch/arm/kernel/traps.c
@@ -365,6 +365,19 @@ asmlinkage void __exception do_undefinstr(struct pt_regs *regs)
 	if (call_undef_hook(regs, instr) == 0)
 		return;
 
+	/* STARGO: hack for DIV emulation */
+	if ((processor_mode(regs) != SVC_MODE) && thumb_mode(regs)) {
+		if ((instr & 0x0310) == 0x0310) { /* Retry for division */
+			unsigned int instr2;
+			get_user(instr2, (u16 __user *)pc + 1);
+			instr <<= 16;
+			instr |= instr2;
+			if (call_undef_hook(regs, instr) == 0)
+				return;
+		}
+	}
+	/* END: STARGO: hack for DIV emulation */
+
 #ifdef CONFIG_DEBUG_USER
 	if (user_debug & UDBG_UNDEFINED) {
 		printk(KERN_INFO "%s (%d): undefined instruction: pc=%p\n",
-- 
cgit v1.1