[3.11.y.z extended stable] Patch "ARM: footbridge: fix VGA initialisation" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    ARM: footbridge: fix VGA initialisation

to the linux-3.11.y-queue branch of the 3.11.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.11.y-queue

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.11.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From 39059ae2c0f2d0b5702c72f4b1883f2c1e07a32a Mon Sep 17 00:00:00 2001
From: Russell King <rmk+kernel at arm.linux.org.uk>
Date: Thu, 28 Nov 2013 21:55:41 +0000
Subject: ARM: footbridge: fix VGA initialisation

commit 43659222e7a0113912ed02f6b2231550b3e471ac upstream.

It's no good setting vga_base after the VGA console has been
initialised, because if we do that we get this:

Unable to handle kernel paging request at virtual address 000b8000
pgd = c0004000
[000b8000] *pgd=07ffc831, *pte=00000000, *ppte=00000000
0Internal error: Oops: 5017 [#1] ARM
Modules linked in:
CPU: 0 PID: 0 Comm: swapper Not tainted 3.12.0+ #49
task: c03e2974 ti: c03d8000 task.ti: c03d8000
PC is at vgacon_startup+0x258/0x39c
LR is at request_resource+0x10/0x1c
pc : [<c01725d0>]    lr : [<c0022b50>]    psr: 60000053
sp : c03d9f68  ip : 000b8000  fp : c03d9f8c
r10: 000055aa  r9 : 4401a103  r8 : ffffaa55
r7 : c03e357c  r6 : c051b460  r5 : 000000ff  r4 : 000c0000
r3 : 000b8000  r2 : c03e0514  r1 : 00000000  r0 : c0304971
Flags: nZCv  IRQs on  FIQs off  Mode SVC_32  ISA ARM  Segment kernel

which is an access to the 0xb8000 without the PCI offset required to
make it work.

Fixes: cc22b4c18540 ("ARM: set vga memory base at run-time")
Signed-off-by: Russell King <rmk+kernel at arm.linux.org.uk>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 arch/arm/mach-footbridge/common.c  | 3 +++
 arch/arm/mach-footbridge/dc21285.c | 2 --
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/arm/mach-footbridge/common.c b/arch/arm/mach-footbridge/common.c
index 2739ca2..e009168 100644
--- a/arch/arm/mach-footbridge/common.c
+++ b/arch/arm/mach-footbridge/common.c
@@ -15,6 +15,7 @@
 #include <linux/init.h>
 #include <linux/io.h>
 #include <linux/spinlock.h>
+#include <video/vga.h>

 #include <asm/pgtable.h>
 #include <asm/page.h>
@@ -196,6 +197,8 @@ void __init footbridge_map_io(void)
 		iotable_init(ebsa285_host_io_desc, ARRAY_SIZE(ebsa285_host_io_desc));
 		pci_map_io_early(__phys_to_pfn(DC21285_PCI_IO));
 	}
+
+	vga_base = PCIMEM_BASE;
 }

 void footbridge_restart(enum reboot_mode mode, const char *cmd)
diff --git a/arch/arm/mach-footbridge/dc21285.c b/arch/arm/mach-footbridge/dc21285.c
index 3490a24..7c2fdae 100644
--- a/arch/arm/mach-footbridge/dc21285.c
+++ b/arch/arm/mach-footbridge/dc21285.c
@@ -18,7 +18,6 @@
 #include <linux/irq.h>
 #include <linux/io.h>
 #include <linux/spinlock.h>
-#include <video/vga.h>

 #include <asm/irq.h>
 #include <asm/mach/pci.h>
@@ -291,7 +290,6 @@ void __init dc21285_preinit(void)
 	int cfn_mode;

 	pcibios_min_mem = 0x81000000;
-	vga_base = PCIMEM_BASE;

 	mem_size = (unsigned int)high_memory - PAGE_OFFSET;
 	for (mem_mask = 0x00100000; mem_mask < 0x10000000; mem_mask <<= 1)
--
1.8.3.2