Commit Graph

5 Commits

Author SHA1 Message Date
Thomas Gleixner d2912cb15b treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500
Based on 2 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 17:09:55 +02:00
Vineet Gupta 45890f6d34 ARC: mm: HIGHMEM: kmap API implementation
Implement kmap* API for ARC.

This enables
 - permanent kernel maps (pkmaps): :kmap() API
 - fixmap : kmap_atomic()

We use a very simple/uniform approach for both (unlike some of the other
arches). So fixmap doesn't use the customary compile time address stuff.
The important semantic is sleep'ability (pkmap) vs. not (fixmap) which
the API guarantees.

Note that this patch only enables highmem for subsequent PAE40 support
as there is no real highmem for ARC in pure 32-bit paradigm as explained
below.

ARC has 2:2 address split of the 32-bit address space with lower half
being translated (virtual) while upper half unstranslated
(0x8000_0000 to 0xFFFF_FFFF). kernel itself is linked at base of
unstranslated space (i.e. 0x8000_0000 onwards), which is mapped to say
DDR 0x0 by external Bus Glue logic (outside the core). So kernel can
potentially access 1.75G worth of memory directly w/o need for highmem.
(the top 256M is taken by uncached peripheral space from 0xF000_0000 to
0xFFFF_FFFF)

In PAE40, hardware can address memory beyond 4G (0x1_0000_0000) while
the logical/virtual addresses remain 32-bits. Thus highmem is required
for kernel proper to be able to access these pages for it's own purposes
(user space is agnostic to this anyways).

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-28 19:49:04 +05:30
Vineet Gupta 8362c389a4 ARC: mm/cache_arc700.c -> mm/cache.c
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-06-19 18:09:32 +05:30
Vineet Gupta 5bba49f539 ARC: [mm] Aliasing VIPT dcache support 4/4
Enforce congruency of userspace shared mappings

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-05-09 22:00:57 +05:30
Vineet Gupta cfdbc2e16e ARC: Build system: Makefiles, Kconfig, Linker script
Arnd in his review pointed out that arch Kconfig organisation has several
deficiencies:

* Build time entries for things which can be runtime extracted from DT
  (e.g. SDRAM size, core clk frequency..)
* Not multi-platform-image-build friendly (choice .. endchoice constructs)
* cpu variants support (750/770) is exclusive.

The first 2 have been fixed in subsequent patches.
Due to the nature of the 750 and 770, it is not possible to build for
both together, w/o special runtime glue code which would hurt
performance.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
2013-02-11 20:00:25 +05:30