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2015-09-22ARM: 8432/1: move VMALLOC_END from 0xff000000 to 0xff800000Nicolas Pitre
There is a 12MB unused region in our memory map between the vmalloc and fixmap areas. This became unused with commit e9da6e9905e6, confirmed with commit 64d3b6a3f480. We also have a 8MB guard area before the vmalloc area. With the default 240MB vmalloc area size and the current VMALLOC_END definition, that means the end of low memory ends up at 0xef800000 which is unfortunate for 768MB machines where 8MB of RAM is lost to himem. Let's move VMALLOC_END to 0xff800000 so the guard area won't chop the top of the 768MB low memory area while keeping the default vmalloc area size unchanged and still preserving a gap between the vmalloc and fixmap areas. Signed-off-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-10-16ARM: expand fixmap region to 3MBRob Herring
With commit a05e54c103b0 ("ARM: 8031/2: change fixmap mapping region to support 32 CPUs"), the fixmap region was expanded to 2MB, but it precluded any other uses of the fixmap region. In order to support other uses the fixmap region needs to be expanded beyond 2MB. Fortunately, the adjacent 1MB range 0xffe00000-0xfff00000 is availabe. Remove fixmap_page_table ptr and lookup the page table via the virtual address so that the fixmap region can span more that one pmd. The 2nd pmd is already created since it is shared with the vector page. Signed-off-by: Rob Herring <robh@kernel.org> [kees: fixed CONFIG_DEBUG_HIGHMEM get_fixmap() calls] [kees: moved pte allocation outside of CONFIG_HIGHMEM] Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Nicolas Pitre <nico@linaro.org>
2014-06-01ARM: 8066/1: correction for ARM patch 8031/2Nicolas Pitre
A small mistake slipped through in memory.txt. Signed-off-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-04-23ARM: 8031/2: change fixmap mapping region to support 32 CPUsLiu Hua
In 32-bit ARM systems, the fixmap mapping region can support no more than 14 CPUs(total: 896k; one CPU: 64K). And we can configure NR_CPUS up to 32. So there is a mismatch. This patch moves fixmapping region downwards to region 0xffc00000- 0xffe00000. Then the fixmap mapping region can support up to 32 CPUs. Reviewed-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Liu Hua <sdu.liu@huawei.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-04-23ARM: 8023/1: remove remnants of the static DMA mappingNicolas Pitre
It looks like the static mapping area for DMA was replaced by dynamic allocation into the vmalloc area by commit e9da6e9905e6 but the information in Documentation/arm/memory.txt was not removed accordingly. CONSISTENT_END in arch/arm/include/asm/memory.h has no more users and can be removed as well. Signed-off-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-07-25ARM: Add fixed PCI i/o mappingRob Herring
This adds a fixed virtual mapping for PCI i/o addresses. The mapping is located at the last 2MB of vmalloc region (0xfee00000-0xff000000). 2MB is used to align with PMD size, but IO_SPACE_LIMIT is 1MB. The space is reserved after .map_io and can be mapped at any time later with pci_ioremap_io. Platforms which need early i/o mapping (e.g. for vga console) can call pci_map_io_early in their .map_io function. This has changed completely from the 1st implementation which only supported creating the static mapping at .map_io. Signed-off-by: Rob Herring <rob.herring@calxeda.com> Cc: Russell King <linux@arm.linux.org.uk> Acked-by: Nicolas Pitre <nico@linaro.org>
2011-11-26ARM: move iotable mappings within the vmalloc regionNicolas Pitre
In order to remove the build time variation between different SOCs with regards to VMALLOC_END, the iotable mappings are now allocated inside the vmalloc region. This allows for VMALLOC_END to be identical across all machines. The value for VMALLOC_END is now set to 0xff000000 which is right where the consistent DMA area starts. To accommodate all static mappings on machines with possible highmem usage, the default vmalloc area size is changed to 240 MB so that VMALLOC_START is no higher than 0xf0000000 by default. Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org> Tested-by: Stephen Warren <swarren@nvidia.com> Tested-by: Kevin Hilman <khilman@ti.com> Tested-by: Jamie Iles <jamie@jamieiles.com>
2010-07-27ARM: 6225/1: make TCM allocation static and common for all archsLinus Walleij
This changes the TCM handling so that a fixed area is reserved at 0xfffe0000-0xfffeffff for TCM. This areas is used by XScale but XScale does not have TCM so the mechanisms are mutually exclusive. This change is needed to make TCM detection more dynamic while still being able to compile code into it, and is a must for the unified ARM goals: the current TCM allocation at different places in memory for each machine would be a nightmare if you want to compile a single image for more than one machine with TCM so it has to be nailed down in one place. Signed-off-by: Linus Walleij <linus.walleij@stericsson.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-02-15ARM: 5930/1: Add PKMAP area description to memory.txt.Fenkart/Bostandzhyan
Also adapts delimiters of neighbouring modules area. Tested-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Andreas Fenkart <andreas.fenkart@streamunlimited.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-07-30ARM: 5624/1: Document cache aliasing regionLinus Walleij
Augment the memory.txt file for ARM to list the cache aliasing region ffff4000-fffffff. Signed-off-by: Linus Walleij <linus.walleij@stericsson.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-03-15[ARM] fixmap supportNicolas Pitre
This is the minimum fixmap interface expected to be implemented by architectures supporting highmem. We have a second level page table already allocated and covering 0xfff00000-0xffffffff because the exception vector page is located at 0xffff0000, and various cache tricks already use some entries above 0xffff0000. Therefore the PTEs covering 0xfff00000-0xfffeffff are free to be used. However the XScale cache flushing code already uses virtual addresses between 0xfffe0000 and 0xfffeffff. So this reserves the 0xfff00000-0xfffdffff range for fixmap stuff. The Documentation/arm/memory.txt information is updated accordingly, including the information about the actual top of DMA memory mapping region which didn't match the code. Signed-off-by: Nicolas Pitre <nico@marvell.com>
2005-11-17[ARM] Fix some corner cases in new mm initialisationRussell King
Document that the VMALLOC_END address must be aligned to 2MB since it must align with a PGD boundary. Allocate the vectors page early so that the flush_cache_all() later will cause any dirty cache lines in the direct mapping will be safely written back. Move the flush_cache_all() to the second local_flush_cache_tlb() and remove the now redundant first local_flush_cache_tlb(). Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-04-16Linux-2.6.12-rc2Linus Torvalds
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!