[PATCH] ARM: mmp: map sram as MT_MEMORY rather than MT_DEVICE
From: Russell King - ARM Linux <hidden>
Date: 2011-08-23 00:08:19
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On Mon, Aug 22, 2011 at 04:47:40PM -0700, Andres Salomon wrote:
quoted hunk ↗ jump to hunk
The sram code allocates memory with ioremap, which assumes MT_DEVICE for memory protections. This explodes when we map sram for power management purposes and then attempt to execute it (jump_to_lp_sram) on the OLPC XO-1.75. Instead, we want to specify MT_MEMORY, which doesn't set the L_PTE_XN bit. Signed-off-by: Andres Salomon <redacted> --- arch/arm/mach-mmp/sram.c | 4 +++- 1 files changed, 3 insertions(+), 1 deletions(-) Eric, this patch is against the devel branch of your pxa tree.diff --git a/arch/arm/mach-mmp/sram.c b/arch/arm/mach-mmp/sram.c index 4304f95..ca4d3c1 100644 --- a/arch/arm/mach-mmp/sram.c +++ b/arch/arm/mach-mmp/sram.c@@ -21,6 +21,7 @@ #include <linux/err.h> #include <linux/slab.h> #include <linux/genalloc.h> +#include <asm/mach/map.h> #include <mach/sram.h>@@ -87,7 +88,8 @@ static int __devinit sram_probe(struct platform_device *pdev) info->sram_phys = (phys_addr_t)res->start; info->sram_size = resource_size(res); - info->sram_virt = ioremap(info->sram_phys, info->sram_size); + info->sram_virt = __arm_ioremap(info->sram_phys, info->sram_size, + MT_MEMORY);
Not a good idea fiddling about under the covers like that. The reason that MT_MEMORY is not in asm/io.h is to stop it being used like this - MT_MEMORY etc are not meant for general purpose use. It needs to be looked at properly rather than working behind the APIs, and making my life a misery by doing so, preventing me from making changes where necessary by this kind of back-door use. I guess we need a new ioremap_xxx() variant to cope with this.