Re: [PATCH V2 0/2] mailbox: tmel-qmp: Introduce QCOM TMEL QMP mailbox driver

[Jeff Johnson <jeff.johnson@oss.qualcomm.com>]

On 12/30/24 21:48, Sricharan R wrote:
> From: Sricharan Ramabadhran <quic_srichara@quicinc.com>
> 
> The QMP mailbox is the primary means of communication between TME-L SS
> and other subsystem on the SoC. A dedicated pair of inbound and outbound
> mailboxes is implemented for each subsystem/external execution environment
> which needs to communicate with TME-L for security services. The inbound
> mailboxes are used to send IPC requests to TME-L, which are then processed
> by TME-L firmware and accordingly the responses are sent to the requestor
> via outbound mailboxes.
> 
> It is an IPC transport protocol which is light weight and supports
> a subset of API's. It handles link initialization, negotiation,
> establishment and communication across client(APPSS/BTSS/AUDIOSS)
> and server(TME-L SS).
> 
>    -----------------------------------------------       ---------------------------------------------------
>   |                                              |       |                                                 |
>   |                 SOC  CLIENT                  | SOC   |                TME-L  SS                        |
>   |                                              | AHB   |                                                 |
>   |     ----------    ---------   ---------      |       | ------    -------     --------    ------------  |
>   |     |        |    |       |   |       |      | WO    | |     | R |     |     |      |    |SERVICES   | |
>   |     | APPS   |<-->| TMEL  |<->|       |------------->| | IN  |-->|     |     | TMEL |    |--------   | |
>   |     |        |    | COM   |   | QMP   |      | RO    | |     | W | QMP |<--->| COM  |<-->| a) ATTEST | |
>   |     |        |    |       |   |       |<-------------| | OUT |<--|     |     |      |    | b) CRYPTO | |
>   |     |        |    |       |   |       |      |       | |     |   |     |     |      |    | .. more   | |
>   |     ---------     ---------   ---------      |       | ------    -------     -------     ------------  |
>   |                                              |       |                                                 |
>    -----------------------------------------------       --------------------------------------------------
> 
> TME-L SS provides different kinds of services like secureboot, remote image authentication,
> key management, crypto, OEM provisioning etc. This patch adds support for remote image
> authentication. Support for rest of the services can be added.
> 
> Remote proc driver subscribes to this mailbox and uses the mbox_send_message to use
> TME-L to securely authenticate/teardown the images.
> 
> Since clients like same rproc driver use SCM/TMEL across socs, the goal here was to abstract the
> TMEL-QMP SS functionality, so that clients should be able to connect and send messages with
> a common API.
> 
> [v1] RFC Post
> 
> [v2]
>      Added HW description in the bindings patch.
>      Fixed review comments for bindings from Krzysztof and Dmitry
>      Changed patch#2 driver to add work for mailbox tx processing    
>      Cleaned up patch#2 for some checkpatch warnings.
>      There are some checkpatch [CHECK] like below, which looks like false positive.
> 
> 	CHECK: Macro argument 'm' may be better as '(m)' to avoid precedence issues
> 	#1072: FILE: include/linux/mailbox/tmelcom-qmp.h:40:
> 	+#define TMEL_MSG_UID_CREATE(m, a)      ((u32)(((m & 0xff) << 8) | (a & 0xff)))
> 
> 
> Sricharan Ramabadhran (2):
>   dt-bindings: mailbox: Document qcom,tmel-qmp
>   mailbox: tmelite-qmp: Introduce TMEL QMP mailbox driver
> 
>  .../bindings/mailbox/qcom,tmelite-qmp.yaml    |  65 ++
>  drivers/mailbox/Kconfig                       |   7 +
>  drivers/mailbox/Makefile                      |   2 +
>  drivers/mailbox/qcom-tmel-qmp.c               | 969 ++++++++++++++++++
>  include/linux/mailbox/tmelcom-qmp.h           | 157 +++
>  5 files changed, 1200 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/mailbox/qcom,tmelite-qmp.yaml
>  create mode 100644 drivers/mailbox/qcom-tmel-qmp.c
>  create mode 100644 include/linux/mailbox/tmelcom-qmp.h
> 

This series was listed as a prerequisite for a WLAN patch I'm
reviewing, and when I used my WLAN automation to pull into my
workspace the following issues were flagged.

From kernel-doc:
drivers/mailbox/qcom-tmel-qmp.c:153: warning: Function parameter or struct member 'qwork' not described in 'qmp_device'
drivers/mailbox/qcom-tmel-qmp.c:153: warning: Function parameter or struct member 'data' not described in 'qmp_device'
drivers/mailbox/qcom-tmel-qmp.c:153: warning: Function parameter or struct member 'ch_in_use' not described in 'qmp_device'
drivers/mailbox/qcom-tmel-qmp.c:304: warning: Function parameter or struct member 'mdev' not described in 'qmp_send_data'
drivers/mailbox/qcom-tmel-qmp.c:304: warning: Excess function parameter 'chan' description in 'qmp_send_data'
drivers/mailbox/qcom-tmel-qmp.c:394: warning: Function parameter or struct member 'mdev' not described in 'qmp_recv_data'
drivers/mailbox/qcom-tmel-qmp.c:394: warning: Excess function parameter 'mbox' description in 'qmp_recv_data'
drivers/mailbox/qcom-tmel-qmp.c:438: warning: Function parameter or struct member 'mdev' not described in 'qmp_rx'
drivers/mailbox/qcom-tmel-qmp.c:438: warning: Excess function parameter 'mbox' description in 'qmp_rx'
drivers/mailbox/qcom-tmel-qmp.c:859: warning: No description found for return value of 'tmel_qmp_mbox_of_xlate'
10 warnings as Errors

From checkpatch --codespell:
1d333d61d25de60704447c9b2dbee165927696d3:16: WARNING:TYPO_SPELLING: 'requestor' may be misspelled - perhaps 'requester'?
1d333d61d25de60704447c9b2dbee165927696d3:76: WARNING:TYPO_SPELLING: 'requestor' may be misspelled - perhaps 'requester'?
total: 0 errors, 2 warnings, 65 lines checked
cb1085a6ed62b0d1c7400ff9257490e431afe7b0:313: WARNING:TYPO_SPELLING: 'initated' may be misspelled - perhaps 'initiated'?
cb1085a6ed62b0d1c7400ff9257490e431afe7b0:316: WARNING:TYPO_SPELLING: 'succes' may be misspelled - perhaps 'success'?
cb1085a6ed62b0d1c7400ff9257490e431afe7b0:357: WARNING:TYPO_SPELLING: 'succes' may be misspelled - perhaps 'success'?
cb1085a6ed62b0d1c7400ff9257490e431afe7b0:910: WARNING:TYPO_SPELLING: 'controlls' may be misspelled - perhaps 'controls'?
total: 0 errors, 4 warnings, 1144 lines checked

/jeff