RE: [PATCH] bus: mhi: core: Add support MHI EE FP for download firmware

From: Carl Yin(殷张成)
Date: Thu Oct 29 2020 - 05:10:09 EST


Hi bbhatt:

On October 29, 2020 5:41 AM, bbhatt wrote:
> On 2020-10-27 18:57, Carl Yin wrote:
> > Hi bbhatt:
> >
> > On Wednesday, October 28, 2020 9:34 AM, bbhatt wrote:
> >> Hi Carl,
> >> On 2020-10-27 16:01, Hemant Kumar wrote:
> >> > Hi Jeff,
> >> >
> >> > On 10/27/20 8:11 AM, Jeffrey Hugo wrote:
> >> >> On 10/27/2020 3:43 AM, carl.yin@xxxxxxxxxxx wrote:
> >> >>> From: "carl.yin" <carl.yin@xxxxxxxxxxx>
> >> >>>
> >> >>> MHI wwan modems support download firmware to nand or emmc by
> >> >>> firehose protocol, process as next:
> >> >>> 1. wwan modem normal bootup and enter EE AMSS, create mhi DIAG
> >> >>> chan device 2. send EDL cmd via DIAG chan, then modem enter EE EDL 3.
> >> >>> boot.c download 'firehose/prog_firehose_sdx55.mbn' via BHI
> >> >>> interface 4. modem enter EE FP, and create mhi EDL chan device 5.
> >> >>> user space tool download FW to modem via EDL chan by firehose
> >> >>> protocol
> >> >>>
> >> >>> Signed-off-by: carl.yin <carl.yin@xxxxxxxxxxx>
> >> >>> ---
> >> >>>   drivers/bus/mhi/core/boot.c     |  4 +++-
> >> >>>   drivers/bus/mhi/core/init.c     |  2 ++
> >> >>>   drivers/bus/mhi/core/internal.h |  1 +
> >> >>>   drivers/bus/mhi/core/main.c     |  3 +++
> >> >>>   drivers/bus/mhi/core/pm.c       | 16 +++++++++++++++-
> >> >>>   include/linux/mhi.h             |  4 +++-
> >> >>>   6 files changed, 27 insertions(+), 3 deletions(-)
> >> >>>
> >> >>> diff --git a/drivers/bus/mhi/core/boot.c
> >> >>> b/drivers/bus/mhi/core/boot.c index 24422f5..ab39ad6 100644
> >> >>> --- a/drivers/bus/mhi/core/boot.c
> >> >>> +++ b/drivers/bus/mhi/core/boot.c
> >> >>> @@ -460,8 +460,10 @@ void mhi_fw_load_handler(struct
> >> >>> mhi_controller
> >> >>> *mhi_cntrl)
> >> >>>           return;
> >> >>>       }
> >> >>> -    if (mhi_cntrl->ee == MHI_EE_EDL)
> >> >>> +    if (mhi_cntrl->ee == MHI_EE_EDL) {
> >> >>> +        mhi_ready_state_transition(mhi_cntrl);
> >> >>>           return;
> >> >>> +    }
> >> >>>       write_lock_irq(&mhi_cntrl->pm_lock);
> >> >>>       mhi_cntrl->dev_state = MHI_STATE_RESET; diff --git
> >> >>> a/drivers/bus/mhi/core/init.c b/drivers/bus/mhi/core/init.c index
> >> >>> ac4aa5c..9c2c2f3 100644
> >> >>> --- a/drivers/bus/mhi/core/init.c
> >> >>> +++ b/drivers/bus/mhi/core/init.c
> >> >>> @@ -26,6 +26,7 @@ const char * const mhi_ee_str[MHI_EE_MAX] = {
> >> >>>       [MHI_EE_WFW] = "WFW",
> >> >>>       [MHI_EE_PTHRU] = "PASS THRU",
> >> >>>       [MHI_EE_EDL] = "EDL",
> >> >>> +    [MHI_EE_FP] = "FP",
> >> >>>       [MHI_EE_DISABLE_TRANSITION] = "DISABLE",
> >> >>>       [MHI_EE_NOT_SUPPORTED] = "NOT SUPPORTED",
> >> >>>   };
> >> >>> @@ -35,6 +36,7 @@ const char * const
> >> >>> dev_state_tran_str[DEV_ST_TRANSITION_MAX] = {
> >> >>>       [DEV_ST_TRANSITION_READY] = "READY",
> >> >>>       [DEV_ST_TRANSITION_SBL] = "SBL",
> >> >>>       [DEV_ST_TRANSITION_MISSION_MODE] = "MISSION_MODE",
> >> >>> +    [DEV_ST_TRANSITION_FP] = "FP",
> >> Longer description here would be nice (FLASH PROGRAMMER).
> > [carl.yin] yes, for SDX24 and SDX55 chip, 'FIREHOSE PROGRAMMER' is
> > more better.
> I agree with Jeff, should be generic.
> >>
> >> >>>       [DEV_ST_TRANSITION_SYS_ERR] = "SYS_ERR",
> >> >>>       [DEV_ST_TRANSITION_DISABLE] = "DISABLE",
> >> >>>   };
> >> >>> diff --git a/drivers/bus/mhi/core/internal.h
> >> >>> b/drivers/bus/mhi/core/internal.h index 4abf0cf..6ae897a 100644
> >> >>> --- a/drivers/bus/mhi/core/internal.h
> >> >>> +++ b/drivers/bus/mhi/core/internal.h
> >> >>> @@ -386,6 +386,7 @@ enum dev_st_transition {
> >> >>>       DEV_ST_TRANSITION_READY,
> >> >>>       DEV_ST_TRANSITION_SBL,
> >> >>>       DEV_ST_TRANSITION_MISSION_MODE,
> >> >>> +    DEV_ST_TRANSITION_FP,
> >> >>>       DEV_ST_TRANSITION_SYS_ERR,
> >> >>>       DEV_ST_TRANSITION_DISABLE,
> >> >>>       DEV_ST_TRANSITION_MAX,
> >> >>> diff --git a/drivers/bus/mhi/core/main.c
> >> >>> b/drivers/bus/mhi/core/main.c index 3950792..e307b58 100644
> >> >>> --- a/drivers/bus/mhi/core/main.c
> >> >>> +++ b/drivers/bus/mhi/core/main.c
> >> >>> @@ -782,6 +782,9 @@ int mhi_process_ctrl_ev_ring(struct
> >> >>> mhi_controller *mhi_cntrl,
> >> >>>               case MHI_EE_SBL:
> >> >>>                   st = DEV_ST_TRANSITION_SBL;
> >> >>>                   break;
> >> >>> +            case MHI_EE_FP:
> >> >>> +                st = DEV_ST_TRANSITION_FP;
> >> >>> +                break;
> >> >>>               case MHI_EE_WFW:
> >> >>>               case MHI_EE_AMSS:
> >> >>>                   st = DEV_ST_TRANSITION_MISSION_MODE;
> diff
> >> --git
> >> >>> a/drivers/bus/mhi/core/pm.c b/drivers/bus/mhi/core/pm.c index
> >> >>> 3de7b16..3c95a5d 100644
> >> >>> --- a/drivers/bus/mhi/core/pm.c
> >> >>> +++ b/drivers/bus/mhi/core/pm.c
> >> >>> @@ -563,7 +563,15 @@ static void mhi_pm_disable_transition(struct
> >> >>> mhi_controller *mhi_cntrl,
> >> >>>       }
> >> >>>       if (cur_state == MHI_PM_SYS_ERR_PROCESS) {
> >> >>> -        mhi_ready_state_transition(mhi_cntrl);
> >> >>> +        if (mhi_get_exec_env(mhi_cntrl) == MHI_EE_EDL
> >> >>> +            && mhi_get_mhi_state(mhi_cntrl) ==
> MHI_STATE_RESET)
> >> {
> >> >>> +            write_lock_irq(&mhi_cntrl->pm_lock);
> >> >>> +            cur_state = mhi_tryset_pm_state(mhi_cntrl,
> >> MHI_PM_POR);
> >> >>> +            write_unlock_irq(&mhi_cntrl->pm_lock);
> >> >>> +            mhi_queue_state_transition(mhi_cntrl,
> >> >>> DEV_ST_TRANSITION_PBL);
> >> >>> +        } else {
> >> >>> +            mhi_ready_state_transition(mhi_cntrl);
> >> >>> +        }
> >> >>>       } else {
> >> >>>           /* Move to disable state */
> >> >>>           write_lock_irq(&mhi_cntrl->pm_lock);
> >> >>> @@ -658,6 +666,12 @@ void mhi_pm_st_worker(struct work_struct
> >> >>> *work)
> >> >>>           case DEV_ST_TRANSITION_MISSION_MODE:
> >> >>>               mhi_pm_mission_mode_transition(mhi_cntrl);
> >> >>>               break;
> >> >>> +        case DEV_ST_TRANSITION_FP:
> >> >>> +            write_lock_irq(&mhi_cntrl->pm_lock);
> >> >>> +            mhi_cntrl->ee = MHI_EE_FP;
> >> >>> +            write_unlock_irq(&mhi_cntrl->pm_lock);
> >> >>> +            mhi_create_devices(mhi_cntrl);
> >> >>> +            break;
> >> >>>           case DEV_ST_TRANSITION_READY:
> >> >>>               mhi_ready_state_transition(mhi_cntrl);
> >> >>>               break;
> >> >>> diff --git a/include/linux/mhi.h b/include/linux/mhi.h index
> >> >>> 6e1122c..4620af8 100644
> >> >>> --- a/include/linux/mhi.h
> >> >>> +++ b/include/linux/mhi.h
> >> >>> @@ -120,6 +120,7 @@ struct mhi_link_info {
> >> >>>    * @MHI_EE_WFW: WLAN firmware mode
> >> >>>    * @MHI_EE_PTHRU: Passthrough
> >> >>>    * @MHI_EE_EDL: Embedded downloader
> >> >>> + * @MHI_EE_FP, Flash Programmer Environment
> >> >>>    */
> >> >>>   enum mhi_ee_type {
> >> >>>       MHI_EE_PBL,
> >> >>> @@ -129,7 +130,8 @@ enum mhi_ee_type {
> >> >>>       MHI_EE_WFW,
> >> >>>       MHI_EE_PTHRU,
> >> >>>       MHI_EE_EDL,
> >> >>> -    MHI_EE_MAX_SUPPORTED = MHI_EE_EDL,
> >> >>> +    MHI_EE_FP,
> >> >>> +    MHI_EE_MAX_SUPPORTED = MHI_EE_FP,
> >> >>>       MHI_EE_DISABLE_TRANSITION, /* local EE, not related to mhi
> >> >>> spec */
> >> >>>       MHI_EE_NOT_SUPPORTED,
> >> >>>       MHI_EE_MAX,
> >> >>>
> >> >>
> >> >> This gets a NACK from me.  I don't see the FP_EE that this patch
> >> >> introduces defined in the spec.  Where did it come from?
> >> >>
> >> > There is indeed a FP EE, BHI spec will be updated with this EE next
> >> > month.
> >> >
> >> > Basically, once device goes to EDL, flash programmer image is
> >> > downloaded using BHI protocol (same as we download SBL image using
> >> > BHI from PBL in current use case). Once it is downloaded intvec
> >> > sends EE change event for FP. Also event is generated for the same
> >> > which is used to create EDL channels (34, 35) which is used by
> >> > flash programmer to flash image for AMSS.
> >> >
> >> >>> 2. send EDL cmd via DIAG chan, then modem enter EE EDL
> >> > #2 needs to be done in cleaner way. From AMSS when diag cmd is sent
> >> > to switch to EDL, device would send SYS_ERR which we can use to do
> >> > a call back to mhi controller to perform power down and power up.
> >> > Instead of moving pm state to POR from disable transition :-
> >> >
> >> The callback that Hemant refers to is for MHI_CB_FATAL_ERROR. It
> >> should be seen by the controller once device enters EDL EE with MHI
> >> in SYS_ERROR state.
> >>
> >> Can you confirm you see this? If yes, it should be used to power down
> >> and power up MHI with EE set to EDL.
> > [carl.yin] from AMSS EE to SBL EE or EDL EE, I think it is not a
> > really ' FATAL_ERROR '.
> > It is a normal EE state change, no need to power down and power up
> > device.
> > When ' FATAL_ERROR ' occurs, we can get really EE state from the MHI
> > devices.
> > Then just stay here, let the user space tools to decide how to handle
> > this new EE.
> >
> Why do you think it is a normal EE change? FATAL ERROR callback is a means to
> notify the controller that the device is back to one of the PBL EEs (PBL/EDL/
> PTHRU) and a clean-up must be done. Hence, the emphasis on doing an MHI
> power down and power up.
>
> Because any move to from AMSS -> PBL is essentially treated as a reboot of the
> device, MHI host should instruct the controller to do the same for MHI.
> Once
> the next power up happens, you are free to load the EDL image because EE will
> be EDL if mhi_cntrl->edl_image is set as 'firehose/prog_firehose_sdx55.mbn'.
>
> This if check is not a good idea. If you want to load the EDL image, just use what
> already exists.
[carl.yin] maybe we should treat EE EDL same as EE RDDM,
When enter EDL/RDDM, just need select a suitable way to download EDL/RDDM image viaBHIe,
then mhi device will auto recovery and enter normal state. do not need to Power on/off.
I find the driver handle RDDM by this way.
Another thing, when enter EE EDL, will not call MHI_CB_FATAL_ERROR

Next is my log:
[ 212.441338] mhi 0000:03:00.0: Preparing channel: 4
[ 212.453829] mhi 0000:03:00.0: Chan: 4 successfully moved to start state
[ 212.453834] mhi 0000:03:00.0: Preparing channel: 5
[ 212.463872] mhi 0000:03:00.0: Chan: 5 successfully moved to start state
[ 212.555416] mhi 0000:03:00.0: local ee:EDL device ee:AMSS dev_state:SYS_ERR
[ 212.555424] CPU: 8 PID: 532 Comm: irq/127-bhi Tainted: G OE 5.8.0-23-generic #24~20.04.1-Ubuntu
[ 212.555426] Hardware name: Dell Inc. OptiPlex 7060/0C96W1, BIOS 1.2.22 11/01/2018
[ 212.555428] Call Trace:
[ 212.555442] dump_stack+0x74/0x9a
[ 212.555454] mhi_intvec_threaded_handler.cold+0x5/0x36 [mhi]
[ 212.555499] mhi 0000:03:00.0: System error detected
[ 212.555519] mhi 0000:03:00.0: Handling state transition: SYS_ERR

For EE is AMSS, so do not call MHI_CB_FATAL_ERROR.
is code BUG? or 'AMSS->EDL' is not fatal error?
irqreturn_t mhi_intvec_threaded_handler(int irq_number, void *priv)
{
...
ee = mhi_cntrl->ee;
mhi_cntrl->ee = mhi_get_exec_env(mhi_cntrl);
dev_dbg(dev, "local ee:%s device ee:%s dev_state:%s\n",
TO_MHI_EXEC_STR(mhi_cntrl->ee), TO_MHI_EXEC_STR(ee),
TO_MHI_STATE_STR(state));
...
if (pm_state == MHI_PM_SYS_ERR_DETECT) {
wake_up_all(&mhi_cntrl->state_event);

/* For fatal errors, we let controller decide next step */
if (MHI_IN_PBL(ee))
mhi_cntrl->status_cb(mhi_cntrl, MHI_CB_FATAL_ERROR);
else
mhi_pm_sys_err_handler(mhi_cntrl);
}
}


> >>
> >> This, along with the mhi_cntrl->edl_image set from the controller,
> >> will result in MHI loading the EDL image for you.
> >> > @@ -563,7 +563,15 @@ static void mhi_pm_disable_transition(struct
> >> >>> mhi_controller *mhi_cntrl,
> >> >>> }
> >> >>> if (cur_state == MHI_PM_SYS_ERR_PROCESS) {
> >> >>> - mhi_ready_state_transition(mhi_cntrl);
> >> >>> + if (mhi_get_exec_env(mhi_cntrl) == MHI_EE_EDL
> >> >>> + && mhi_get_mhi_state(mhi_cntrl) == MHI_STATE_RESET)
> {
> >> >>> + write_lock_irq(&mhi_cntrl->pm_lock);
> >> >>> + cur_state = mhi_tryset_pm_state(mhi_cntrl,
> MHI_PM_POR);
> >> >>> + write_unlock_irq(&mhi_cntrl->pm_lock);
> >> >>> + mhi_queue_state_transition(mhi_cntrl,
> >> >>> DEV_ST_TRANSITION_PBL);
> >> >>> + } else {
> >> >>> + mhi_ready_state_transition(mhi_cntrl);
> >> >>> + }
> > [carl.yin] I am working on SDX24 and SDX55 chip, maybe the process is
> > different form MHI wlan chips?
> > For these chips, SBL EE means the chip enter RAMDUMP state. mhi driver
> > just need export SAHARA chan to user space, then user space tool to
> > catch RADDUMP.
> >
> >> >
> >> > Thanks,
> >> > Hemant
> >>
> >> Thanks,
> >> Bhaumik
> >> --
> >> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora
> >> Forum, a Linux Foundation Collaborative Project
>
> Thanks,
> Bhaumik
> --
> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a
> Linux Foundation Collaborative Project