As noted by David:
pte_page() is a macro defined as follows;
include/asm-sh/pgtable.h
#define pte_page(x) phys_to_page(pte_val(x)&PTE_PHYS_MASK)
include/asm-sh/page.h
#define phys_to_page(phys) (pfn_to_page(phys >> PAGE_SHIFT))
So as you can see the phys_to_page() macro doesn't wrap the 'phys'
parameter in parentheses so we end up with;
pte_val(x)&PTE_PHYS_MASK >> PAGE_SHIFT
Which is not what we wanted as '>>' has a higher precedence than bitwise
AND. I dug into the git repository and I believe this bug was added with
this commit (104b8deaa5);
2006-03-27 KAMEZAWA Hiroyuki [PATCH] unify pfn_to_page: sh pfn_to_page
-#define phys_to_page(phys) (mem_map + (((phys)-__MEMORY_START) >>
PAGE_SHIFT))
-#define page_to_phys(page) (((page - mem_map) << PAGE_SHIFT) +
__MEMORY_START)
+#define phys_to_page(phys) (pfn_to_page(phys >> PAGE_SHIFT))
+#define page_to_phys(page) (page_to_pfn(page) << PAGE_SHIFT)
Reported-by: David ADDISON <david.addison@st.com>
Reported-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
The extended mode TLB requires both 64-bit PTEs and a 64-bit pgprot,
correspondingly, the PGD also has to be 64-bits, so fix that up.
The kernel and user permission bits really are decoupled in early
cuts of the silicon, which means that we also have to set corresponding
kernel permissions on user pages or we end up with user pages that the
kernel simply can't touch (!).
Finally, with those things corrected, really enable MMUCR.ME and
correct the PTEA value (this simply needs to be the upper 32-bits
of the PTE, with the size and protection bit encoding).
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This reworks the cache mode configuration in Kconfig, and allows for
explicit selection of write-back/write-through/off configurations.
All of the cache flushing routines are optimized away for the off
case.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
The first 1MB of P3 space was reserved and used for page colouring,
as we've reworked that to use fixmaps, we can reclaim the space and
hand it back to VMALLOC_START.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Most architectures defined three macros, MK_IOSPACE_PFN(), GET_IOSPACE()
and GET_PFN() in pgtable.h. However, the only callers of any of these
macros are in Sparc specific code, either in arch/sparc, arch/sparc64 or
drivers/sbus.
This patch removes the redundant macros from all architectures except
sparc and sparc64.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This ended up causing problems for older parts (particularly ones
using PTEA). Revert this for now, it can be added back in once it's
had some more testing.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This converts the lazy dcache handling to the model described in
Documentation/cachetlb.txt and drops the ptep_get_and_clear() hacks
used for the aliasing dcaches on SH-4 and SH7705 in 32kB mode. As a
bonus, this slightly cuts down on the cache flushing frequency.
With that and the PTEA handling out of the way, the update_mmu_cache()
implementations can be consolidated, and we no longer have to worry
about which configuration the cache is in for the SH7705 case.
And finally, explicitly disable the lazy writeback on SMP (SH-4A).
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
There were a few more things that needed fixing up, namely THREAD_SIZE
and the TLB miss handler where certain PTRS_PER_PGD == PTRS_PER_PTE
assumptions were being made.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
In the 64-bit PTE case there's no point in restricting the encoding
to the low bits of the PTE, we can instead bump all of this up to
the high 32 bits and extend PTE_FILE_MAX_BITS to 32, adopting the
same convention used by x86 PAE.
There's a minor discrepency between the number of bits used for the
swap type encoding between 32 and 64-bit PTEs, but this is unlikely
to cause any problem given the extended offset.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
When hugetlbpage support isn't enabled, this can be bogus.
Wrap it back in _PAGE_FLAGS_HARD to avoid changes to the
base PTE when not aiming for larger sizes.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
There were a number of places that made evil PAGE_SIZE == 4k
assumptions that ended up breaking when trying to play with
8k and 64k page sizes, this fixes those up.
The most significant change is the way we load THREAD_SIZE,
previously this was done via:
mov #(THREAD_SIZE >> 8), reg
shll8 reg
to avoid a memory access and allow the immediate load. With
a 64k PAGE_SIZE, we're out of range for the immediate load
size without resorting to special instructions available in
later ISAs (movi20s and so on). The "workaround" for this is
to bump up the shift to 10 and insert a shll2, which gives a
bit more flexibility while still being much cheaper than a
memory access.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Handle simple TLB miss faults which can be resolved completely
from the page table in assembler.
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Remove extra bits from the pmd structure and store a kernel logical
address rather than a physical address. This allows it to be directly
dereferenced. Another piece of wierdness inherited from x86.
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This adds some preliminary support for the SH-X2 MMU, used by
newer SH-4A parts (particularly SH7785).
This MMU implements a 'compat' mode with SH-X MMUs and an
'extended' mode for SH-X2 extended features. Extended features
include additional page sizes (8kB, 4MB, 64MB), as well as the
addition of page execute permissions.
The extended mode attributes are placed in a second data array,
which requires us to switch to 64-bit PTEs when in X2 mode.
With the addition of the exec perms, we also overhaul the mmap
prots somewhat, now that it's possible to handle them more
intelligently.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Set the SHM alignment at runtime, based off of probed cache desc.
Optimize get_unmapped_area() to only colour align shared mappings.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
