[Maverick] [ti-omap4] SRU: A workaround for highmem issue on OMAP4 platform

[Bryan Wu]

On Sun, Sep 26, 2010 at 11:01 PM, Nicolas Pitre
<nicolas.pitre at canonical.com> wrote:
> On Sun, 26 Sep 2010, Ricardo Salveti de Araujo wrote:
>
>> On Fri, Sep 24, 2010 at 03:04:10AM -0300, Ricardo Salveti de Araujo wrote:
>> > Will also test it with only one cpu to see if this could be realted with SMP
>> > issues.
>>
>> Ok, tested the same kernel but running with only one CPU, for 40 hours (what gave me
>> 15 builds), and went all fine, without any errors at both userspace and kernelspace.
>>
>> So it seems that this data abort exception could be related with concurrency and
>> SMP support at our kernel.
>
> Right.  So I'd suggest you keep highmem off, and 2g:2g on (with the
> VMALLOC_END fix), then try to reliably reproduce the issue with that
> configuration and fix it before involving highmem again.  While highmem
> may make the problem more visible, it also brings a set of added
> complexity of its own which would make the tracking of the issue much
> harder.
>
>
> Nicolas
>

I disabled CONFIG_CACHE_L2X0 L2 cache controller for omap4. So far for
the SMP kernel with mem=1G, kernel building is running correctly.
I will test more. It looks like L2 cache controlling has some issue.


>From 0743374a52900030b54f643820dc8f8f71e98651 Mon Sep 17 00:00:00 2001
From: Bryan Wu <bryan.wu at canonical.com>
Date: Sun, 26 Sep 2010 20:35:48 +0800
Subject: [PATCH] UBUNTU: [Config] Disable L2 cache for OMAP4

Signed-off-by: Bryan Wu <bryan.wu at canonical.com>
---
 debian.ti-omap4/config/config.common.ubuntu |    7 ++-----
 1 files changed, 2 insertions(+), 5 deletions(-)

diff --git a/debian.ti-omap4/config/config.common.ubuntu
b/debian.ti-omap4/config/config.common.ubuntu
index 8d46b55..8f5b7e9 100644
--- a/debian.ti-omap4/config/config.common.ubuntu
+++ b/debian.ti-omap4/config/config.common.ubuntu
@@ -320,8 +320,7 @@ CONFIG_C2PORT=m
 CONFIG_CACHEFILES=m
 # CONFIG_CACHEFILES_DEBUG is not set
 # CONFIG_CACHEFILES_HISTOGRAM is not set
-CONFIG_CACHE_L2X0=y
-CONFIG_CACHE_PL310=y
+# CONFIG_CACHE_L2X0 is not set
 # CONFIG_CAIF is not set
 CONFIG_CAN=m
 CONFIG_CAN_BCM=m
@@ -928,6 +927,7 @@ CONFIG_HID_WACOM=m
 CONFIG_HID_ZEROPLUS=m
 # CONFIG_HID_ZYDACRON is not set
 CONFIG_HIGHMEM=y
+# CONFIG_HIGHPTE is not set
 CONFIG_HIGH_RES_TIMERS=y
 CONFIG_HOSTAP=m
 # CONFIG_HOSTAP_FIRMWARE is not set
@@ -1928,8 +1928,6 @@ CONFIG_OMFS_FS=m
 CONFIG_OPROFILE=y
 CONFIG_OSF_PARTITION=y
 # CONFIG_OTUS is not set
-CONFIG_OUTER_CACHE=y
-CONFIG_OUTER_CACHE_SYNC=y
 CONFIG_P54_COMMON=m
 CONFIG_P54_LEDS=y
 CONFIG_P54_SPI=m
@@ -1970,7 +1968,6 @@ CONFIG_PHONET=m
 CONFIG_PHYLIB=y
 # CONFIG_PHYS_ADDR_T_64BIT is not set
 CONFIG_PID_NS=y
-# CONFIG_PL310_ERRATA_588369 is not set
 # CONFIG_PLAT_SPEAR is not set
 CONFIG_PLIP=m
 # CONFIG_PM is not set
-- 
1.7.0.4


-- 
Bryan Wu <bryan.wu at canonical.com>
Kernel Developer    +86.138-1617-6545 Mobile
Ubuntu Kernel Team
Canonical Ltd.      www.canonical.com
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