Re: [PATCH 2/3] msm: Peripheral Image Loader (PIL) driver
From: Bryan Huntsman
Date: Wed Mar 16 2011 - 17:22:59 EST
On 03/16/2011 03:20 AM, Daniel Walker wrote:
> On Wed, 2011-03-09 at 20:44 -0800, Stephen Boyd wrote:
>> On 8660, the modem, dsp, and sensors peripherals require their
>> firmware to be loaded into memory before they can be properly
>> taken out of reset.
>> Drivers are expected to call pil_get() when they wish to load a
>> peripheral. This will initiate multiple firmware_request()s for
>> the metadata and image blobs for a peripheral. Once the image has
>> been loaded into memory, it is validated and brought out of reset
>> via the peripheral reset driver.
> Why can't this be part of the generic firmware request API ?
The generic firmware request API gets a blob from userspace. The PIL
driver uses this interface to get blobs. The additions here are:
- ref counting, per-name
- peripheral reset sequence, per-name
- configurable loading mechanism, secure vs. non-secure
- common format for retrieving metadata to verify image integrity
Since several peripherals need this exact sequence, it made sense to
create a small driver for this functionality.
>> Change-Id: I041139464bbd3b646b82370ab540f40b0ac9af6b
> Can't have Change-Id's ..
Dave noted this for the first patch in the series. For subsequent
postings, Steve will remove the Change-Ids. Otherwise, Dave said he
would remove them prior to adding them to the MSM tree.
>> Reviewed-by: Saravana Kannan <skannan@xxxxxxxxxxxxxx>
>> Signed-off-by: Stephen Boyd <sboyd@xxxxxxxxxxxxxx>
>> arch/arm/mach-msm/Kconfig | 13 +
>> arch/arm/mach-msm/Makefile | 2 +
>> arch/arm/mach-msm/include/mach/peripheral-loader.h | 23 +
>> arch/arm/mach-msm/peripheral-loader.c | 402
>> arch/arm/mach-msm/peripheral-loader.h | 38 ++
>> arch/arm/mach-msm/peripheral-reset.c | 528
>> 6 files changed, 1006 insertions(+), 0 deletions(-)
>> create mode 100644 arch/arm/mach-msm/include/mach/peripheral-loader.h
>> create mode 100644 arch/arm/mach-msm/peripheral-loader.c
>> create mode 100644 arch/arm/mach-msm/peripheral-loader.h
>> create mode 100644 arch/arm/mach-msm/peripheral-reset.c
>> diff --git a/arch/arm/mach-msm/Kconfig b/arch/arm/mach-msm/Kconfig
>> index 997c5bd..25b73b0 100644
>> --- a/arch/arm/mach-msm/Kconfig
>> +++ b/arch/arm/mach-msm/Kconfig
>> @@ -210,4 +210,17 @@ config IOMMU_API
>> config MSM_SCM
>> +config MSM_PIL
>> + bool "Peripheral image loading (PIL)"
>> + select FW_LOADER
>> + select MSM_SCM
>> + depends on ARCH_MSM8X60
>> + help
>> + Some peripherals need to be loaded into memory before they
>> can be
>> + brought out of reset.
>> + Say yes to support these devices.
> You shouldn't be adding anything like this to the Kconfig. To me if you
> add stuff like this it's a big red flag.
> I didn't review the rest sign it might be wasted effort on my part..
Would you elaborate on your objection here? Should the Kconfig be
dropped and the Makefile use 'obj-$(ARCH_MSM8X60)'? That doesn't make
sense to me since we already have a 2nd architecture, 8960, that uses
PIL. How do you think this should be handled? Thanks.
Sent by an employee of the Qualcomm Innovation Center, Inc.
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