[3.5.yuz,extended,stable] Patch "ARM: at91: at91sam9g10: fix SOC type detection" has been added to staging queue

Message ID 1353559715-2248-1-git-send-email-herton.krzesinski@canonical.com
State New
Headers show

Commit Message

Herton Ronaldo Krzesinski Nov. 22, 2012, 4:48 a.m.
This is a note to let you know that I have just added a patch titled

    ARM: at91: at91sam9g10: fix SOC type detection

to the linux-3.5.y-queue branch of the 3.5.yuz extended stable tree 
which can be found at:


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

For more information about the 3.5.yuz tree, see



From 4fcf06db603b4222b4d7ca191ce2a7cc71341c4c Mon Sep 17 00:00:00 2001
From: Ivan Shugov <ivan.shugov@gmail.com>
Date: Wed, 24 Oct 2012 11:02:44 +0200
Subject: [PATCH] ARM: at91: at91sam9g10: fix SOC type detection

commit 3d9a0183dd3423353e9e363bcc261c1220d05f9f upstream.

Newer at91sam9g10 SoC revision can't be detected, so the kernel can't boot with
this kind of kernel panic:
"AT91: Impossible to detect the SOC type"

CPU: ARM926EJ-S [41069265] revision 5 (ARMv5TEJ), cr=00053177
CPU: VIVT data cache, VIVT instruction cache
Machine: Atmel AT91SAM9G10-EK
Ignoring tag cmdline (using the default kernel command line)
bootconsole [earlycon0] enabled
Memory policy: ECC disabled, Data cache writeback
Kernel panic - not syncing: AT91: Impossible to detect the SOC type
[<c00133d4>] (unwind_backtrace+0x0/0xe0) from [<c02366dc>] (panic+0x78/0x1cc)
[<c02366dc>] (panic+0x78/0x1cc) from [<c02fa35c>] (at91_map_io+0x90/0xc8)
[<c02fa35c>] (at91_map_io+0x90/0xc8) from [<c02f9860>] (paging_init+0x564/0x6d0)
[<c02f9860>] (paging_init+0x564/0x6d0) from [<c02f7914>] (setup_arch+0x464/0x704)
[<c02f7914>] (setup_arch+0x464/0x704) from [<c02f44f8>] (start_kernel+0x6c/0x2d4)
[<c02f44f8>] (start_kernel+0x6c/0x2d4) from [<20008040>] (0x20008040)

The reason for this is that the Debug Unit Chip ID Register has changed between
Engineering Sample and definitive revision of the SoC. Changing the check of
cidr to socid will address the problem. We do not integrate this check to the
list just above because we also have to make sure that the extended id is

Signed-off-by: Ivan Shugov <ivan.shugov@gmail.com>
[nicolas.ferre@atmel.com: change commit message]
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com>
 arch/arm/mach-at91/setup.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)



diff --git a/arch/arm/mach-at91/setup.c b/arch/arm/mach-at91/setup.c
index 944bffb..31bb13d 100644
--- a/arch/arm/mach-at91/setup.c
+++ b/arch/arm/mach-at91/setup.c
@@ -151,7 +151,7 @@  static void __init soc_detect(u32 dbgu_base)

 	/* at91sam9g10 */
-	if ((cidr & ~AT91_CIDR_EXT) == ARCH_ID_AT91SAM9G10) {
+	if ((socid & ~AT91_CIDR_EXT) == ARCH_ID_AT91SAM9G10) {
 		at91_soc_initdata.type = AT91_SOC_SAM9G10;
 		at91_boot_soc = at91sam9261_soc;