Align the start address and size of VRAM area to 2M as per comments from
Russell King:
> > So, why SZ_2M?
>
> Firstly, that's the granularity which we allocate page tables - one
> Linux page table covers 2MB of memory. We want to avoid creating page
> tables for the main memory mapping as that increases TLB pressure through
> the use of additional TLB entries, and more page table walks.
>
> Plus, we never used to allow the kernel's direct memory mapping to be
> mapped at anything less than section size - this restriction has since
> been lifted due to OMAP SRAM problems, but I'd rather we stuck with it
> to ensure that we have proper behaviour from all parts of the system.
>
> Secondly, we don't want to end up with lots of fragmentation at the end
> of the memory mapping as that'll reduce performance, not only by making
> the pfn_valid() search more expensive.
>
> Emsuring a minimum allocation size and alignment makes sure that the
> regions can be coalesced together into one block, and minimises run-time
> expenses.
>
> So please, 2MB, or if you object, at the _very_ _least_ 1MB. But
> definitely not PAGE_SIZE.
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@nokia.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Use memblock_free() and memblock_remove() to remove the allocated or
reserved VRAM area from normal kernel memory.
This is a slightly modified version of patches from Felipe Contreras and
Namhyung Kim.
Reported-by: Felipe Contreras <felipe.contreras@gmail.com>
Reported-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@nokia.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Improve the error prints to give more information about the offending
address & size.
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@nokia.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Fix typo in commit dbe3039 ("memblock/arm: Use memblock_region_is_memory()
for omap fb") - it should be memblock_is_region_memory().
Reported-by: Tomi Valkeinen <tomi.valkeinen@nokia.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Kevin Hilman <khilman@deeprootsystems.com>
Cc: ext Grazvydas Ignotas <notasas@gmail.com>
LKML-Reference: <4CABFADA.9020305@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
In commit 2b0d8c251b the __early_param is
replaced with the generic early_param. This patch fixes the parameter passing
for the vram.
Signed-off-by: Thomas Weber <weber@corscience.de>
[tomi.valkeinen@nokia.com: changed the commit prefix]
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@nokia.com>
Add a Video RAM manager for OMAP 2 and 3 platforms. VRAM manager is used
to allocate large continuous blocks of SDRAM or SRAM. The features VRAM
manager has that are missing from dma_alloc_* functions are:
- Support for OMAP2's SRAM
- Allocate without ioremapping
- Allocate at defined physical addresses
- Allows larger VRAM area and larger allocations
The upcoming DSS2 uses VRAM manager.
VRAM area size can be defined in kernel config, board file or with
kernel boot parameters. Board file definition overrides kernel config,
and boot parameter overrides kernel config and board file.
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@nokia.com>
Tomi Valkeinen