linux.git/Documentation/arm/memory.txt, branch master

docs: arm: convert docs to ReST and rename to *.rst

2019-07-15T12:20:24+00:00

Converts ARM the text files to ReST, preparing them to be an
architecture book.

The conversion is actually:
  - add blank lines and identation in order to identify paragraphs;
  - fix tables markups;
  - add some lists markups;
  - mark literal blocks;
  - adjust title markups.

At its new index.rst, let's add a :orphan: while this is not linked to
the main index.rst file, in order to avoid build warnings.

Signed-off-by: Mauro Carvalho Chehab 
Reviewed-by Corentin Labbe  # For sun4i-ss

ARM: 8432/1: move VMALLOC_END from 0xff000000 to 0xff800000

2015-09-22T07:13:57+00:00

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 
Signed-off-by: Russell King

ARM: expand fixmap region to 3MB

2014-10-16T21:38:52+00:00

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 
[kees: fixed CONFIG_DEBUG_HIGHMEM get_fixmap() calls]
[kees: moved pte allocation outside of CONFIG_HIGHMEM]
Signed-off-by: Kees Cook 
Acked-by: Nicolas Pitre

ARM: 8066/1: correction for ARM patch 8031/2

2014-06-01T00:13:18+00:00

A small mistake slipped through in memory.txt.

Signed-off-by: Nicolas Pitre 
Signed-off-by: Russell King

ARM: 8031/2: change fixmap mapping region to support 32 CPUs

2014-04-23T10:09:42+00:00

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 
Signed-off-by: Liu Hua 
Signed-off-by: Russell King

ARM: 8023/1: remove remnants of the static DMA mapping

2014-04-23T00:24:33+00:00

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 
Signed-off-by: Russell King

ARM: Add fixed PCI i/o mapping

2012-07-25T14:26:42+00:00

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 
Cc: Russell King 
Acked-by: Nicolas Pitre

ARM: move iotable mappings within the vmalloc region

2011-11-27T00:21:26+00:00

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 
Tested-by: Stephen Warren 
Tested-by: Kevin Hilman 
Tested-by: Jamie Iles

ARM: 6225/1: make TCM allocation static and common for all archs

2010-07-27T09:42:38+00:00

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 
Signed-off-by: Russell King

ARM: 5930/1: Add PKMAP area description to memory.txt.

2010-02-15T21:40:33+00:00

Also adapts delimiters of neighbouring modules area.

Tested-by: H Hartley Sweeten 
Signed-off-by: Andreas Fenkart 
Signed-off-by: Russell King