Re: [PATCH v2] bus: mhi: core: Add support MHI EE FP for download firmware

[Manivannan Sadhasivam]

On Mon, Nov 02, 2020 at 08:34:14AM -0800, Bhaumik Bhatt wrote:
> On 2020-11-02 04:27, 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. modem boot up and enter EE AMSS, create DIAG channels (4, 5) device
> > 2. user space tool send EDL command via DIAG channel,
> >    then modem enter EE EDL
> > 3. boot.c download 'flash programmer image' via BHI interface
> > 4. modem enter EE FP, and create EDL channels (34, 35) device
> > 5. user space tool download 'firmware image' to modem via EDL channels
> >    by firehose protocol
> > 
> > Signed-off-by: carl.yin <carl.yin@xxxxxxxxxxx>
> > ---
> >  drivers/bus/mhi/core/init.c     |  2 ++
> >  drivers/bus/mhi/core/internal.h |  1 +
> >  drivers/bus/mhi/core/main.c     |  5 ++++-
> >  drivers/bus/mhi/core/pm.c       | 13 ++++++++++++-
> >  include/linux/mhi.h             |  4 +++-
> >  5 files changed, 22 insertions(+), 3 deletions(-)
> > 
> > diff --git a/drivers/bus/mhi/core/init.c b/drivers/bus/mhi/core/init.c
> > index ac4aa5c..e34616b 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] = "FLASH PROGRAMMER",
> >  	[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] = "FLASH_PROGRAMMER",
> >  	[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..a1e1561 100644
> > --- a/drivers/bus/mhi/core/main.c
> > +++ b/drivers/bus/mhi/core/main.c
> > @@ -422,7 +422,7 @@ irqreturn_t mhi_intvec_threaded_handler(int
> > irq_number, void *priv)
> >  		wake_up_all(&mhi_cntrl->state_event);
> > 
> >  		/* For fatal errors, we let controller decide next step */
> > -		if (MHI_IN_PBL(ee))
> > +		if (MHI_IN_PBL(mhi_cntrl->ee))
> Let's please have this as a separate patch with a fixes tag, as it fixes a
> pre-existing bug. I am sure Mani would want this.

Yes. It is not recommended to club changes like this onto a single patch.

Thanks,
Mani

> >  			mhi_cntrl->status_cb(mhi_cntrl, MHI_CB_FATAL_ERROR);
> >  		else
> >  			mhi_pm_sys_err_handler(mhi_cntrl);
> > @@ -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;
> When do you get this EE event on the control event ring? Does it come by
> after you
> have detected EE as FP from mhi_sync_power_up() and move to ready and then
> M0?
> >  			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..2d68812 100644
> > --- a/drivers/bus/mhi/core/pm.c
> > +++ b/drivers/bus/mhi/core/pm.c
> > @@ -658,6 +658,12 @@ 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;
> > @@ -1077,10 +1083,15 @@ int mhi_sync_power_up(struct mhi_controller
> > *mhi_cntrl)
> > 
> >  	wait_event_timeout(mhi_cntrl->state_event,
> >  			   MHI_IN_MISSION_MODE(mhi_cntrl->ee) ||
> > +			   mhi_cntrl->ee == MHI_EE_FP ||
> >  			   MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state),
> >  			   msecs_to_jiffies(mhi_cntrl->timeout_ms));
> > 
> > -	ret = (MHI_IN_MISSION_MODE(mhi_cntrl->ee)) ? 0 : -ETIMEDOUT;
> > +	if (mhi_cntrl->ee == MHI_EE_FP)
> > +		mhi_queue_state_transition(mhi_cntrl, DEV_ST_TRANSITION_READY);
> > +	else
> > +		ret = (MHI_IN_MISSION_MODE(mhi_cntrl->ee)) ? 0 : -ETIMEDOUT;
> > +
> >  	if (ret)
> >  		mhi_power_down(mhi_cntrl, false);
> > 
> We should come up with a better design for this later on.
> > 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,
> 
> Thanks,
> Bhaumik
> -- 
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