On Tue, 23 Aug 2011 08:07:41 +0800
Eric Miao<eric.y.miao@xxxxxxxxx> wrote:
On Tue, Aug 23, 2011 at 7:47 AM, Andres Salomon<dilinger@xxxxxxxxxx>
wrote:
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<dilinger@xxxxxxxxxx>
---
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);
I doubt MT_MEMORY is intended for use with __arm_ioremap(). There
could be other way around to the L_PTE_XN bit.
One other way I'm actually thinking of is to add the SRAM mapping to
mmp_map_io(). The difference of SRAM offset/size may result the
separation of mmp_map_io() into {pxa168,pxa910,mmp2}_map_io()
if necessary.
I guess I don't follow. I think you're talking about adding it to the
standard_io_desc array, but that would require having it pre-mapped and
knowing the virtual address. Or were you planning to ioremap it?