Re: [PATCH v1 4/7] bus: mhi: core: Add support for Flash Programmer execution environment
From: Loic Poulain
Date: Tue Mar 30 2021 - 03:55:00 EST
On Tue, 30 Mar 2021 at 03:28, Bhaumik Bhatt <bbhatt@xxxxxxxxxxxxxx> wrote:
>
> From: Carl Yin <carl.yin@xxxxxxxxxxx>
>
> MHI WWAN modems support downloading firmware to NAND or eMMC
> using Firehose protocol with process as follows:
> 1. Modem boots up, enters AMSS execution environment and the
> device later enters EDL (Emergency Download) mode through any
> mechanism host can use such as a diag command.
> 2. Modem enters SYS_ERROR, MHI host handles SYS_ERROR transition.
> 3. EDL image for device to enter 'Flash Programmer' execution
> environment is then flashed via BHI interface from host.
> 4. Modem enters MHI READY -> M0 and sends the Flash Programmer
> execution environment change to host.
> 5. Following that, EDL/FIREHOSE channels (34, 35) are made
> available from the host.
> 6. User space tool for downloading firmware image to modem over
> the EDL channels using Firehose protocol. Link to USB flashing
> tool: https://git.linaro.org/landing-teams/working/qualcomm/qdl.git/
>
> Make the necessary changes to allow for this sequence to occur and
> allow using the Flash Programmer execution environment.
>
> Signed-off-by: Carl Yin <carl.yin@xxxxxxxxxxx>
> Co-developed-by: Bhaumik Bhatt <bbhatt@xxxxxxxxxxxxxx>
> Signed-off-by: Bhaumik Bhatt <bbhatt@xxxxxxxxxxxxxx>
Reviewed-by: Loic Poulain <loic.poulain@xxxxxxxxxx>