RE: [PATCH] ARM: SAMSUNG: Fix for S3C2412 EBI memory mapping.

[Kukjin Kim <kgene.kim@samsung.com>]

José Miguel Gonçalves wrote:
> 
> On 10-05-2012 10:25, Kukjin Kim wrote:
> > José Miguel Gonçalves wrote:
> >> While upgrading the kernel on a S3C2412 based board I've noted that it
> was
> >> impossible to boot the board with a 2.6.32 or upper kernel.
> >> I've tracked down the problem to the EBI virtual memory mapping that is
> in
> >> conflict with the IO mapping definition in arch/arm/mach-
> s3c24xx/s3c2412.c.
> >>
> >> Signed-off-by: José Miguel Gonçalves<jose.goncalves@inov.pt>
> >> ---
> >>   arch/arm/plat-samsung/include/plat/map-s3c.h |    2 +-
> >>   1 files changed, 1 insertions(+), 1 deletions(-)
> >>
> >> diff --git a/arch/arm/plat-samsung/include/plat/map-s3c.h
> b/arch/arm/plat-
> >> samsung/include/plat/map-s3c.h
> >> index 7d04875..c0c70a8 100644
> >> --- a/arch/arm/plat-samsung/include/plat/map-s3c.h
> >> +++ b/arch/arm/plat-samsung/include/plat/map-s3c.h
> >> @@ -22,7 +22,7 @@
> >>   #define S3C24XX_VA_WATCHDOG	S3C_VA_WATCHDOG
> >>
> >>   #define S3C2412_VA_SSMC		S3C_ADDR_CPU(0x00000000)
> >> -#define S3C2412_VA_EBI		S3C_ADDR_CPU(0x00010000)
> >> +#define S3C2412_VA_EBI		S3C_ADDR_CPU(0x00100000)
> >>
> >>   #define S3C2410_PA_UART		(0x50000000)
> >>   #define S3C24XX_PA_UART		S3C2410_PA_UART
> >> --
> >> 1.7.5.4
> > Yeah, as you said, the mapping for SSMC invade EBI area but I think,
> just SZ_4K is enough for SSMC. So following is better in this case. How do
> you think? And there is no problem on your board?
> >
> > diff --git a/arch/arm/mach-s3c24xx/s3c2412.c b/arch/arm/mach-
> s3c24xx/s3c2412.c
> > index d4bc7f9..ac906bf 100644
> > --- a/arch/arm/mach-s3c24xx/s3c2412.c
> > +++ b/arch/arm/mach-s3c24xx/s3c2412.c
> > @@ -72,7 +72,7 @@ static struct map_desc s3c2412_iodesc[] __initdata = {
> >   	{
> >   		.virtual = (unsigned long)S3C2412_VA_SSMC,
> >   		.pfn     = __phys_to_pfn(S3C2412_PA_SSMC),
> > -		.length  = SZ_1M,
> > +		.length  = SZ_4K,
> >   		.type    = MT_DEVICE,
> >   	},
> >   	{
> >
> 
> It does not work! I tried also a 64K length and also did not work. With
> your patch
> my console (with earlyprintk set) only displays the following:
> 
> ## Booting image at 30800000 ...
>     Image Name:   Linux-3.2.16-inov1
>     Created:      2012-05-10  12:42:49 UTC
>     Image Type:   ARM Linux Kernel Image (uncompressed)
>     Data Size:    1202592 Bytes =  1.1 MB
>     Load Address: 30008000
>     Entry Point:  30008000
>     Verifying Checksum ... OK
> OK
> 
> Starting kernel ...
> 
> Uncompressing Linux... done, booting the kernel.
> Linux version 3.2.16-inov1 (jmpg@st-ze) (gcc version 4.6.4 20120402
> (prerelease)
> (crosstool-NG 1.15.2) ) #3 PREEMPT Thu May 10 13:42:48 WEST 2012
> CPU: ARM926EJ-S [41069265] revision 5 (ARMv5TEJ), cr=00053177
> CPU: VIVT data cache, VIVT instruction cache
> Machine: SMDK2412
> bootconsole [earlycon0] enabled
> Memory policy: ECC disabled, Data cache writeback
> CPU S3C2412 (id 0x32412003)
> 
> My guess is that the MMU initialization on the S3C2412 chip only allows a
> minimum
> of 1MB for the page size.
> 
Hmm, could be... there is no smdk2412 on my desk :(

OK, will apply your fix.
Thanks.

Best regards,
Kgene.
--
Kukjin Kim <kgene.kim@samsung.com>, Senior Engineer,
SW Solution Development Team, Samsung Electronics Co., Ltd.