From cc4a474873ecf79775bef6b2e73a8b0c7e13b95f Mon Sep 17 00:00:00 2001
From: Alexander Graf <agraf@suse.de>
Date: Fri, 4 Mar 2016 01:10:12 +0100
Subject: [PATCH] arm: Allow EFI payload code to take exceptions

There are 2 ways an EFI payload could return into u-boot:

  - Callback function
  - Exception

While in EFI payload mode, r9 is owned by the payload and may not contain
a valid pointer to gd, so we need to fix it up. We do that properly for the
payload to callback path already.

This patch also adds gd pointer restoral for the exception path.

Signed-off-by: Alexander Graf <agraf@suse.de>
---
 arch/arm/lib/interrupts.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/arch/arm/lib/interrupts.c b/arch/arm/lib/interrupts.c
index ec3fb77f851..ed83043abb4 100644
--- a/arch/arm/lib/interrupts.c
+++ b/arch/arm/lib/interrupts.c
@@ -22,6 +22,7 @@
 #include <common.h>
 #include <asm/proc-armv/ptrace.h>
 #include <asm/u-boot-arm.h>
+#include <efi_loader.h>
 
 DECLARE_GLOBAL_DATA_PTR;
 
@@ -165,6 +166,7 @@ void show_regs (struct pt_regs *regs)
 
 void do_undefined_instruction (struct pt_regs *pt_regs)
 {
+	efi_restore_gd();
 	printf ("undefined instruction\n");
 	show_regs (pt_regs);
 	bad_mode ();
@@ -172,6 +174,7 @@ void do_undefined_instruction (struct pt_regs *pt_regs)
 
 void do_software_interrupt (struct pt_regs *pt_regs)
 {
+	efi_restore_gd();
 	printf ("software interrupt\n");
 	show_regs (pt_regs);
 	bad_mode ();
@@ -179,6 +182,7 @@ void do_software_interrupt (struct pt_regs *pt_regs)
 
 void do_prefetch_abort (struct pt_regs *pt_regs)
 {
+	efi_restore_gd();
 	printf ("prefetch abort\n");
 	show_regs (pt_regs);
 	bad_mode ();
@@ -186,6 +190,7 @@ void do_prefetch_abort (struct pt_regs *pt_regs)
 
 void do_data_abort (struct pt_regs *pt_regs)
 {
+	efi_restore_gd();
 	printf ("data abort\n");
 	show_regs (pt_regs);
 	bad_mode ();
@@ -193,6 +198,7 @@ void do_data_abort (struct pt_regs *pt_regs)
 
 void do_not_used (struct pt_regs *pt_regs)
 {
+	efi_restore_gd();
 	printf ("not used\n");
 	show_regs (pt_regs);
 	bad_mode ();
@@ -200,6 +206,7 @@ void do_not_used (struct pt_regs *pt_regs)
 
 void do_fiq (struct pt_regs *pt_regs)
 {
+	efi_restore_gd();
 	printf ("fast interrupt request\n");
 	show_regs (pt_regs);
 	bad_mode ();
@@ -208,6 +215,7 @@ void do_fiq (struct pt_regs *pt_regs)
 #ifndef CONFIG_USE_IRQ
 void do_irq (struct pt_regs *pt_regs)
 {
+	efi_restore_gd();
 	printf ("interrupt request\n");
 	show_regs (pt_regs);
 	bad_mode ();