On Mon, 21 Feb 2022 at 10:27, 谭 永林 yonglin.tan@outlook.com wrote:

Dear Loic,

The Qualcomm x24&x55&x6x platform are all using SAHARA port to collect memory dump log. User can use QLOG tool to collect the whole memory dump of device while the device entered into Dump mode. The firehose protocol is used to download FW from the host, it's different from SAHARA. MHI CH 2&3 are used as SAHARA CH but firehose use 34&35 CH.

Ah right, firehose programmer is loaded when entering EDL mode, not SBL.

The bus driver use " MHI_CHANNEL_CONFIG_UL&DL_SBL " to initiate SAHARA CH configs.

The code is Quectel EM1XX channel config. MHI_CHANNEL_CONFIG_DL_SBL(3, "SAHARA", 32, 0),

For example,

• Once the device crashed due to some reasons.
• The module entered into DUMP mode(SBL Stage), and changed the EE to SBL.
• Then the host should detect the change and re-enumerate the SAHARA port.
• Then users can use QLOG tool to collect the Device Memory LOG by SAHARA Protocol via CH 2&3.

OK, you should add that to the commit message.

Also, instead of exposing the raw sahara protocol, can't this be integrated with the devcoredump framework (https://lwn.net/Articles/610887/)?

Regards, Loic