Hi Ezequiel,
On Thursday 28 November 2013 21:00:43 Ezequiel Garcia wrote:
> In order to remove the following ugly message:
>
> BUG: mapping for 0x00000000 at 0xff000000 out of vmalloc space
>
> the iotable mappings should be re-located inside the vmalloc
> region. Such move was introduced at commit:
>
> commit 0536bdf33faff4d940ac094c77998cfac368cfff
> Author: Nicolas Pitre <[email protected]>
> Date: Thu Aug 25 00:35:59 2011 -0400
>
> ARM: move iotable mappings within the vmalloc region
>
> While at it, condition the mapping to PXA25x and PXA27x, which
> are the only platforms where it's used.
>
> Cc: Nicolas Pitre <[email protected]>
> Cc: Russell King - ARM Linux <[email protected]>
> Cc: David Heidelberger <[email protected]>
> Signed-off-by: Ezequiel Garcia <[email protected]>
> ---
> David,
>
> Is it possible for you to give this a try on your board?
I'm running into the same issue on a PXA270 system.
UNCACHED_PHYS_0 is used as an immediate operand to a mov instruction, and thus
needs to be encoded as a shifted 8-bit value. One simple solution would be to
hardcode it to 0xfd000000 (0xfe000000 is already used for the IMEMC mapping).
Another solution would be to keep the UNCACHED_PHYS_0 mapping at the end of
the vmalloc area (with a fix for the UL problem due to VMALLOC_END) and modify
pxa2[57]x_finish_suspend and pm_enter_standby_start to use an ldr instruction
instead of a move instruction to load the address.
As a side note, the IMEMC mapping seems unused, maybe we could thus reclaim it
and use 0xfe000000 for UNCACHED_PHYS_0.
Do you plan to submit a v3 of this patch ?
> arch/arm/mach-pxa/generic.c | 6 ++++--
> arch/arm/mach-pxa/include/mach/hardware.h | 5 +++--
> 2 files changed, 7 insertions(+), 4 deletions(-)
>
> diff --git a/arch/arm/mach-pxa/generic.c b/arch/arm/mach-pxa/generic.c
> index 4225417..3c1b4fa 100644
> --- a/arch/arm/mach-pxa/generic.c
> +++ b/arch/arm/mach-pxa/generic.c
> @@ -83,11 +83,13 @@ static struct map_desc common_io_desc[] __initdata = {
> .pfn = __phys_to_pfn(0x40000000),
> .length = 0x02000000,
> .type = MT_DEVICE
> +#if defined(CONFIG_PXA25x) || defined(CONFIG_PXA27x)
> }, { /* UNCACHED_PHYS_0 */
> - .virtual = 0xff000000,
> + .virtual = UNCACHED_PHYS_0,
> .pfn = __phys_to_pfn(0x00000000),
> - .length = 0x00100000,
> + .length = UNCACHED_SIZE,
> .type = MT_DEVICE
> +#endif
> }
> };
>
> diff --git a/arch/arm/mach-pxa/include/mach/hardware.h
> b/arch/arm/mach-pxa/include/mach/hardware.h index ccb06e4..b365a72 100644
> --- a/arch/arm/mach-pxa/include/mach/hardware.h
> +++ b/arch/arm/mach-pxa/include/mach/hardware.h
> @@ -14,13 +14,14 @@
> #define __ASM_ARCH_HARDWARE_H
>
> #include <mach/addr-map.h>
> +#include <asm/pgtable.h>
>
> /*
> * Workarounds for at least 2 errata so far require this.
> * The mapping is set in mach-pxa/generic.c.
> */
> -#define UNCACHED_PHYS_0 0xff000000
> -#define UNCACHED_ADDR UNCACHED_PHYS_0
> +#define UNCACHED_PHYS_0 (VMALLOC_END - UNCACHED_SIZE)
> +#define UNCACHED_SIZE SZ_1M
>
> /*
> * Intel PXA2xx internal register mapping:
--
Regards,
Laurent Pinchart
On Apr 09, Laurent Pinchart wrote:
> Hi Ezequiel,
>
> On Thursday 28 November 2013 21:00:43 Ezequiel Garcia wrote:
> > In order to remove the following ugly message:
> >
> > BUG: mapping for 0x00000000 at 0xff000000 out of vmalloc space
> >
> > the iotable mappings should be re-located inside the vmalloc
> > region. Such move was introduced at commit:
> >
> > commit 0536bdf33faff4d940ac094c77998cfac368cfff
> > Author: Nicolas Pitre <[email protected]>
> > Date: Thu Aug 25 00:35:59 2011 -0400
> >
> > ARM: move iotable mappings within the vmalloc region
> >
> > While at it, condition the mapping to PXA25x and PXA27x, which
> > are the only platforms where it's used.
> >
> > Cc: Nicolas Pitre <[email protected]>
> > Cc: Russell King - ARM Linux <[email protected]>
> > Cc: David Heidelberger <[email protected]>
> > Signed-off-by: Ezequiel Garcia <[email protected]>
> > ---
> > David,
> >
> > Is it possible for you to give this a try on your board?
>
> I'm running into the same issue on a PXA270 system.
>
> UNCACHED_PHYS_0 is used as an immediate operand to a mov instruction, and thus
> needs to be encoded as a shifted 8-bit value. One simple solution would be to
> hardcode it to 0xfd000000 (0xfe000000 is already used for the IMEMC mapping).
>
> Another solution would be to keep the UNCACHED_PHYS_0 mapping at the end of
> the vmalloc area (with a fix for the UL problem due to VMALLOC_END) and modify
> pxa2[57]x_finish_suspend and pm_enter_standby_start to use an ldr instruction
> instead of a move instruction to load the address.
>
> As a side note, the IMEMC mapping seems unused, maybe we could thus reclaim it
> and use 0xfe000000 for UNCACHED_PHYS_0.
>
> Do you plan to submit a v3 of this patch ?
>
Not really. I've been a bit busy and couldn't work any longer on this issue,
so feel free to pick the task :-)
--
Ezequiel Garc?a, Free Electrons
Embedded Linux, Kernel and Android Engineering
http://free-electrons.com