Re: [PATCH v4 1/6] bus: mhi: core: Set BHI/BHIe offsets on power up preparation

[Manivannan Sadhasivam]

On Thu, May 06, 2021 at 12:51:40PM -0700, Bhaumik Bhatt wrote:
> Set the BHI and/or BHIe offsets in mhi_prepare_for_power_up(),
> rearrange the function, and remove the equivalent from
> mhi_async_power_up(). This helps consolidate multiple checks
> in different parts of the driver and can help MHI fail early on
> before power up begins if the offsets are not read correctly.
> 
> Signed-off-by: Bhaumik Bhatt <bbhatt@xxxxxxxxxxxxxx>
> Reviewed-by: Jeffrey Hugo <quic_jhugo@xxxxxxxxxxx>
> Reviewed-by: Hemant Kumar <hemantk@xxxxxxxxxxxxxx>

Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>

Thanks,
Mani

> ---
>  drivers/bus/mhi/core/init.c | 42 +++++++++++++++++++++++-------------------
>  drivers/bus/mhi/core/pm.c   | 28 ++++------------------------
>  2 files changed, 27 insertions(+), 43 deletions(-)
> 
> diff --git a/drivers/bus/mhi/core/init.c b/drivers/bus/mhi/core/init.c
> index c81b377..11c7a3d 100644
> --- a/drivers/bus/mhi/core/init.c
> +++ b/drivers/bus/mhi/core/init.c
> @@ -1063,7 +1063,7 @@ EXPORT_SYMBOL_GPL(mhi_free_controller);
>  int mhi_prepare_for_power_up(struct mhi_controller *mhi_cntrl)
>  {
>  	struct device *dev = &mhi_cntrl->mhi_dev->dev;
> -	u32 bhie_off;
> +	u32 bhi_off, bhie_off;
>  	int ret;
>  
>  	mutex_lock(&mhi_cntrl->pm_mutex);
> @@ -1072,29 +1072,36 @@ int mhi_prepare_for_power_up(struct mhi_controller *mhi_cntrl)
>  	if (ret)
>  		goto error_dev_ctxt;
>  
> -	/*
> -	 * Allocate RDDM table if specified, this table is for debugging purpose
> -	 */
> -	if (mhi_cntrl->rddm_size) {
> -		mhi_alloc_bhie_table(mhi_cntrl, &mhi_cntrl->rddm_image,
> -				     mhi_cntrl->rddm_size);
> +	ret = mhi_read_reg(mhi_cntrl, mhi_cntrl->regs, BHIOFF, &bhi_off);
> +	if (ret) {
> +		dev_err(dev, "Error getting BHI offset\n");
> +		goto error_reg_offset;
> +	}
> +	mhi_cntrl->bhi = mhi_cntrl->regs + bhi_off;
>  
> -		/*
> -		 * This controller supports RDDM, so we need to manually clear
> -		 * BHIE RX registers since POR values are undefined.
> -		 */
> +	if (mhi_cntrl->fbc_download || mhi_cntrl->rddm_size) {
>  		ret = mhi_read_reg(mhi_cntrl, mhi_cntrl->regs, BHIEOFF,
>  				   &bhie_off);
>  		if (ret) {
>  			dev_err(dev, "Error getting BHIE offset\n");
> -			goto bhie_error;
> +			goto error_reg_offset;
>  		}
> -
>  		mhi_cntrl->bhie = mhi_cntrl->regs + bhie_off;
> +	}
> +
> +	if (mhi_cntrl->rddm_size) {
> +		/*
> +		 * This controller supports RDDM, so we need to manually clear
> +		 * BHIE RX registers since POR values are undefined.
> +		 */
>  		memset_io(mhi_cntrl->bhie + BHIE_RXVECADDR_LOW_OFFS,
>  			  0, BHIE_RXVECSTATUS_OFFS - BHIE_RXVECADDR_LOW_OFFS +
>  			  4);
> -
> +		/*
> +		 * Allocate RDDM table for debugging purpose if specified
> +		 */
> +		mhi_alloc_bhie_table(mhi_cntrl, &mhi_cntrl->rddm_image,
> +				     mhi_cntrl->rddm_size);
>  		if (mhi_cntrl->rddm_image)
>  			mhi_rddm_prepare(mhi_cntrl, mhi_cntrl->rddm_image);
>  	}
> @@ -1103,11 +1110,8 @@ int mhi_prepare_for_power_up(struct mhi_controller *mhi_cntrl)
>  
>  	return 0;
>  
> -bhie_error:
> -	if (mhi_cntrl->rddm_image) {
> -		mhi_free_bhie_table(mhi_cntrl, mhi_cntrl->rddm_image);
> -		mhi_cntrl->rddm_image = NULL;
> -	}
> +error_reg_offset:
> +	mhi_deinit_dev_ctxt(mhi_cntrl);
>  
>  error_dev_ctxt:
>  	mutex_unlock(&mhi_cntrl->pm_mutex);
> diff --git a/drivers/bus/mhi/core/pm.c b/drivers/bus/mhi/core/pm.c
> index e2e59a3..adf426c 100644
> --- a/drivers/bus/mhi/core/pm.c
> +++ b/drivers/bus/mhi/core/pm.c
> @@ -1066,28 +1066,8 @@ int mhi_async_power_up(struct mhi_controller *mhi_cntrl)
>  	if (ret)
>  		goto error_setup_irq;
>  
> -	/* Setup BHI offset & INTVEC */
> +	/* Setup BHI INTVEC */
>  	write_lock_irq(&mhi_cntrl->pm_lock);
> -	ret = mhi_read_reg(mhi_cntrl, mhi_cntrl->regs, BHIOFF, &val);
> -	if (ret) {
> -		write_unlock_irq(&mhi_cntrl->pm_lock);
> -		goto error_bhi_offset;
> -	}
> -
> -	mhi_cntrl->bhi = mhi_cntrl->regs + val;
> -
> -	/* Setup BHIE offset */
> -	if (mhi_cntrl->fbc_download) {
> -		ret = mhi_read_reg(mhi_cntrl, mhi_cntrl->regs, BHIEOFF, &val);
> -		if (ret) {
> -			write_unlock_irq(&mhi_cntrl->pm_lock);
> -			dev_err(dev, "Error reading BHIE offset\n");
> -			goto error_bhi_offset;
> -		}
> -
> -		mhi_cntrl->bhie = mhi_cntrl->regs + val;
> -	}
> -
>  	mhi_write_reg(mhi_cntrl, mhi_cntrl->bhi, BHI_INTVEC, 0);
>  	mhi_cntrl->pm_state = MHI_PM_POR;
>  	mhi_cntrl->ee = MHI_EE_MAX;
> @@ -1098,7 +1078,7 @@ int mhi_async_power_up(struct mhi_controller *mhi_cntrl)
>  	if (!MHI_IN_PBL(current_ee) && current_ee != MHI_EE_AMSS) {
>  		dev_err(dev, "Not a valid EE for power on\n");
>  		ret = -EIO;
> -		goto error_bhi_offset;
> +		goto error_async_power_up;
>  	}
>  
>  	state = mhi_get_mhi_state(mhi_cntrl);
> @@ -1117,7 +1097,7 @@ int mhi_async_power_up(struct mhi_controller *mhi_cntrl)
>  		if (!ret) {
>  			ret = -EIO;
>  			dev_info(dev, "Failed to reset MHI due to syserr state\n");
> -			goto error_bhi_offset;
> +			goto error_async_power_up;
>  		}
>  
>  		/*
> @@ -1139,7 +1119,7 @@ int mhi_async_power_up(struct mhi_controller *mhi_cntrl)
>  
>  	return 0;
>  
> -error_bhi_offset:
> +error_async_power_up:
>  	mhi_deinit_free_irq(mhi_cntrl);
>  
>  error_setup_irq:
> -- 
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>