We weren't explicitly setting the page table bits we desired
in user_prot in the protection table, which resulted in the
user mappings for v6 CPUs being marked global.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
No point checking what CPU architecture level we have each time
within the loop, so precompute the base PMD flags outside the
loop.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Deepak Saxena
Working on adding support for 36-bit static mappings for ARMv6 and
Intel's XSC3 core and noticed that alloc_init_supersection currently
increments the phys addr by 1MB on each of the 16 iterations and then
forces alignment to supersection size (16MB). This is really uneeded
b/c we have already forced the phys address to be 16MB aligned in
create_mapping(). Furthermore, this breaks 36-bit addressing b/c bits
[23:20] of the PMD contain bits [35:32] of the physical address and
the masking causes us to loose those bits thus ending up with an
incorrect virt -> phys translation. The other option is to have an
alloc_init_supersection36.
Tested on Intel IXP2350 CPU with 36-bit static I/O mappings.
Signed-off-by: Deepak Saxena <dsaxena@plexity.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Unfortunately, we can't use the "user" bit in the page tables to
control whether a page table entry is "global" or "asid" specific,
since the vector page is mapped as "user" accessible but is not
process specific.
Therefore, give direct control of the ARMv6 "nG" (not global)
bit to the mm layers.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARMv6 introduces memory types into the page tables. Mark devices
mappings with the "shared device" memory type.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Deepak Saxena
The code in mm-armv.c checks for the condition (cpu_architecture()<= ARMv5)
in a few places but should be checking for ARMv5TEJ as the MMU is shared
across all v5 variations.
Signed-off-by: Deepak Saxena <dsaxena@plexity.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
It doesn't make sense for this to be in mm-armv.c now that 26-bit
ARM support is no longer integrated into arch/arm.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
It doesn't make sense to have the PGD kernel pointers initialisation
separate from the PGD user pointers, especially when we clean the
data cache over the whole range.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Add pmd_off() and pmd_off_k() to obtain the pmd pointer for a
virtual address, and use them throughout the mm initialisation.
Signed-off-by: Russell King <rmk@arm.linux.org.uk>
Patch from George G. Davis
This patch is required for kernel XIP support on ARMv6 machines. It ensures that the access permission bits for kernel XIP section descriptors are APX=1 and AP[1:0]=01, which is Kernel read-only/User no access permissions. Prior to this change, kernel XIP section descriptor access permissions were set to Kernel no access/User no access on ARMv6 machines and the kernel would therefore hang upon entry to userspace when set_fs(USER_DS) was executed.
Signed-off-by: Steve Longerbeam
Signed-off-by: George G. Davis
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Russell King