Now that the kernel load address and KSEG physical base address have
their own Kconfig symbols PLATFORM_DEFAULT_MEM seems redundant. It makes
little sense to use it in MMU configurations instead of KSEG_PADDR.
In noMMU configurations there's no explicit KSEG, so it's still useful
for the early cache initialization and definition of ARCH_PFN_OFFSET,
which affects mem_map size.
- limit it to noMMU; MMU variants have XCHAL_KSEG_PADDR and
XCHAL_KSEG_SIZE;
- don't use it to define TASK_SIZE or MAX_LOW_PFN: first doesn't make
any difference in noMMU, second is meaningless as there's no high
memory;
- don't add default physical memory region: memory layout should come
from the DT, bootloader tags, or memmap= command line parameter.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Make kernel load address explicit, independent of the selected MMU
configuration and configurable from Kconfig. Do not restrict it to the
first 512MB of the physical address space.
Cleanup kernel memory layout macros:
- rename VECBASE_RESET_VADDR to VECBASE_VADDR, XC_VADDR to VECTOR_VADDR;
- drop VIRTUAL_MEMORY_ADDRESS and LOAD_MEMORY_ADDRESS;
- introduce PHYS_OFFSET and use it in __va and __pa definitions;
- synchronize MMU/noMMU vectors, drop unused NMI vector;
- replace hardcoded vectors offset of 0x3000 with Kconfig symbol.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
MMUv3 is able to support low memory bigger than 128MB.
Implement 256MB and 512MB KSEG layouts:
- add Kconfig selector for KSEG layout;
- add KSEG base address, size and alignment definitions to
arch/xtensa/include/asm/kmem_layout.h;
- use new definitions in TLB initialization;
- add build time memory map consistency checks.
See Documentation/xtensa/mmu.txt for the details of new memory layouts.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Create a header dedicated to memory layout definitions. Include it from
places where these definitions are needed.
Express vmalloc area address, VIRTUAL_MEMORY_ADDRESS and KERNELOFFSET
through KSEG address.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
noMMU configuration doesn't use special area for vmalloc allocations,
don't print it in the memory map.
PAGE_OFFSET is fixed to 0 in noMMU, use min_low_pfn and max_low_pfn for
lowmem range display.
Make all XCHAL_KSEG_* constants unsigned long for consistency with other
addresses.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Map high memory pages at virtual addresses with color that match color
of their physical address. Existing cache alias management mechanisms
may be used with such pages.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Existing clear_user_page and copy_user_page cannot be used with highmem
because they calculate physical page address from its virtual address
and do it incorrectly in case of high memory page mapped with
kmap_atomic. Also kmap is not needed, as most likely userspace mapping
color would be different from the kmapped color.
Provide clear_user_highpage and copy_user_highpage functions that
determine if temporary mapping is needed for the pages. Move most of the
logic of the former clear_user_page and copy_user_page to
xtensa/mm/cache.c only leaving temporary mapping setup, invalidation and
clearing/copying in the xtensa/mm/misc.S. Rename these functions to
clear_page_alias and copy_page_alias.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Remove heading and trailing spaces, trim trailing lines, and wrap lines
that are longer than 80 characters.
Signed-off-by: Chris Zankel <chris@zankel.net>
This is not useful: it provides page->virtual and is used with highmem.
xtensa has no support for highmem and those HIGHMEM bits which are found
by grep are partly implemented. The interesting functions like kmap() are
missing. If someone actually implements the complete HIGHMEM support he
could use HASHED_PAGE_VIRTUAL like most others do.
Signed-off-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Cc: Chris Zankel <chris@zankel.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The current asm-generic/page.h only contains the get_order
function, and asm-generic/uaccess.h only implements
unaligned accesses. This renames the file to getorder.h
and uaccess-unaligned.h to make room for new page.h
and uaccess.h file that will be usable by all simple
(e.g. nommu) architectures.
Signed-off-by: Remis Lima Baima <remis.developer@googlemail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
The current assumption of the memory code is that the first RAM PFN in
the system is 0.
Adjust the relevant code to play well with setups where memory starts
at higher addresses, indicated by PLATFORM_DEFAULT_MEM_START.
The new memory model looks like this:
+----------+--+----------------------+----------------+
| | | | |
| | | RAM | |
| | | | |
+----------+--+----------------------+----------------+
| | | | |
+- PFN 0 | +- min_low_pfn +- max_low_pfn +- max_pfn
|
+- ARCH_PFN_OFFSET
+- PLATFORM_DEFAULT_MEM_START >> PAGE_SIZE
The memory map contains pages starting from pfn ARCH_PFN_OFFSET up to
max_low_pfn. The only zone used right now will span exactly the same
region.
Usually, ARCH_PFN_OFFSET and min_low_pfn are the same value. Handle
them separately for robustness. Gapping pages will be in the memory
map but marked as reserved and won't be touched.
Signed-off-by: Johannes Weiner <jw@emlix.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
Move all header files for xtensa to arch/xtensa/include and platform and
variant header files to the appropriate arch/xtensa/platforms/ and
arch/xtensa/variants/ directories.
Moving the files gets also rid of all uses of symlinks in the Makefile.
This has been completed already for the majority of the architectures
and xtensa is one out of six missing.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Chris Zankel <chris@zankel.net>
