Re: [PATCH] bus: mhi: host: Add session ID to MHI controller

From: Manivannan Sadhasivam <mani@kernel.org>
To: Qiang Yu <quic_qianyu@quicinc.com>
Cc: quic_hemantk@quicinc.com, loic.poulain@linaro.org,
	mhi@lists.linux.dev, linux-arm-msm@vger.kernel.org,
	linux-kernel@vger.kernel.org, quic_cang@quicinc.com,
	mrana@quicinc.com
Subject: Re: [PATCH] bus: mhi: host: Add session ID to MHI controller
Date: Tue, 1 Nov 2022 17:15:54 +0530	[thread overview]
Message-ID: <20221101114554.GD54667@thinkpad> (raw)
In-Reply-To: <7dc5b87a-1413-f7cb-4fdc-93828252c4f1@quicinc.com>

On Mon, Oct 31, 2022 at 04:54:55PM +0800, Qiang Yu wrote:
> 
> On 10/29/2022 1:20 AM, Manivannan Sadhasivam wrote:
> > On Mon, Oct 10, 2022 at 12:41:10PM +0800, Qiang Yu wrote:
> > > Session ID to be used during BHI transfers to recognize a
> > > particular session are currently not being stored in the MHI
> > > controller structure. Store them to allow for tracking and other
> > > future usage.
> > > 
> > > Signed-off-by: Qiang Yu <quic_qianyu@quicinc.com>
> > Who/what is going to use this session id?
> Sometimes, we may find some error logs and want to see what happens on
> device when host is printing these error logs.
> Session id can help us find the logs we want.

Okay. Please add this info to the commit message.

Thanks,
Mani

> > 
> > Thanks,
> > Mani
> > 
> > > ---
> > >   drivers/bus/mhi/host/boot.c | 8 ++++----
> > >   include/linux/mhi.h         | 1 +
> > >   2 files changed, 5 insertions(+), 4 deletions(-)
> > > 
> > > diff --git a/drivers/bus/mhi/host/boot.c b/drivers/bus/mhi/host/boot.c
> > > index 26d0edd..5bed8b51 100644
> > > --- a/drivers/bus/mhi/host/boot.c
> > > +++ b/drivers/bus/mhi/host/boot.c
> > > @@ -231,7 +231,7 @@ static int mhi_fw_load_bhi(struct mhi_controller *mhi_cntrl,
> > >   			   dma_addr_t dma_addr,
> > >   			   size_t size)
> > >   {
> > > -	u32 tx_status, val, session_id;
> > > +	u32 tx_status, val;
> > >   	int i, ret;
> > >   	void __iomem *base = mhi_cntrl->bhi;
> > >   	rwlock_t *pm_lock = &mhi_cntrl->pm_lock;
> > > @@ -253,16 +253,16 @@ static int mhi_fw_load_bhi(struct mhi_controller *mhi_cntrl,
> > >   		goto invalid_pm_state;
> > >   	}
> > > -	session_id = MHI_RANDOM_U32_NONZERO(BHI_TXDB_SEQNUM_BMSK);
> > > +	mhi_cntrl->session_id = MHI_RANDOM_U32_NONZERO(BHI_TXDB_SEQNUM_BMSK);
> > >   	dev_dbg(dev, "Starting image download via BHI. Session ID: %u\n",
> > > -		session_id);
> > > +		mhi_cntrl->session_id);
> > >   	mhi_write_reg(mhi_cntrl, base, BHI_STATUS, 0);
> > >   	mhi_write_reg(mhi_cntrl, base, BHI_IMGADDR_HIGH,
> > >   		      upper_32_bits(dma_addr));
> > >   	mhi_write_reg(mhi_cntrl, base, BHI_IMGADDR_LOW,
> > >   		      lower_32_bits(dma_addr));
> > >   	mhi_write_reg(mhi_cntrl, base, BHI_IMGSIZE, size);
> > > -	mhi_write_reg(mhi_cntrl, base, BHI_IMGTXDB, session_id);
> > > +	mhi_write_reg(mhi_cntrl, base, BHI_IMGTXDB, mhi_cntrl->session_id);
> > >   	read_unlock_bh(pm_lock);
> > >   	/* Wait for the image download to complete */
> > > diff --git a/include/linux/mhi.h b/include/linux/mhi.h
> > > index a5441ad..8b3c934 100644
> > > --- a/include/linux/mhi.h
> > > +++ b/include/linux/mhi.h
> > > @@ -405,6 +405,7 @@ struct mhi_controller {
> > >   	u32 minor_version;
> > >   	u32 serial_number;
> > >   	u32 oem_pk_hash[MHI_MAX_OEM_PK_HASH_SEGMENTS];
> > > +	u32 session_id;
> > >   	struct mhi_event *mhi_event;
> > >   	struct mhi_cmd *mhi_cmd;
> > > -- 
> > > The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> > > a Linux Foundation Collaborative Project
> > > 
> > > 
> 

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