[U-Boot] [PATCH v4 18/23] ARM: Implement non-cached memory support

Simon Glass sjg at chromium.org
Thu Dec 18 21:39:39 CET 2014


Hi Albert,

On 18 December 2014 at 13:17, Albert ARIBAUD <albert.u.boot at aribaud.net> wrote:
> Hello Simon,
>
> On Wed, 10 Dec 2014 08:03:29 -0700, Simon Glass <sjg at chromium.org>
> wrote:
>> Hi Albert,
>>
>> On 9 December 2014 at 22:25, Simon Glass <sjg at chromium.org> wrote:
>> > From: Thierry Reding <treding at nvidia.com>
>> >
>> > Implement an API that can be used by drivers to allocate memory from a
>> > pool that is mapped uncached. This is useful if drivers would otherwise
>> > need to do extensive cache maintenance (or explicitly maintaining the
>> > cache isn't safe).
>> >
>> > The API is protected using the new CONFIG_SYS_NONCACHED_MEMORY setting.
>> > Boards can set this to the size to be used for the non-cached area. The
>> > area will typically be right below the malloc() area, but architectures
>> > should take care of aligning the beginning and end of the area to honor
>> > any mapping restrictions. Architectures must also ensure that mappings
>> > established for this area do not overlap with the malloc() area (which
>> > should remain cached for improved performance).
>> >
>> > While the API is currently only implemented for ARM v7, it should be
>> > generic enough to allow other architectures to implement it as well.
>> >
>> > Signed-off-by: Thierry Reding <treding at nvidia.com>
>> > Signed-off-by: Simon Glass <sjg at chromium.org>
>> > ---
>> >
>> > Changes in v4: None
>> > Changes in v3:
>> > - Avoid build error with noncached_init() when the dcache is disabled
>> >
>> >  README                        | 19 +++++++++++++++++++
>> >  arch/arm/include/asm/system.h |  5 +++++
>> >  arch/arm/lib/cache.c          | 44 +++++++++++++++++++++++++++++++++++++++++++
>> >  common/board_r.c              | 11 +++++++++++
>> >  4 files changed, 79 insertions(+)
>>
>> I think you have applied the other cache patches. Are you OK with this
>> one? I would like to get this series applied very soon (after DM I2C)
>> as it's been around since August.
>
> This is delegated to Tom Warren in Patchwork. I'm delegating it to
> myself and applying it; if Tom has applied it too, this should not
> cause a major merge issue.

Agreed, sounds good, thanks.

Regards,
Simon


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