Re: [Patch v4 03/10] memory: tegra: add interconnect support for DRAM scaling in Tegra234

[Sumit Gupta]

On 28/03/23 16:35, Thierry Reding wrote:
> On Tue, Mar 28, 2023 at 09:31:58AM +0200, Krzysztof Kozlowski wrote:
> > On 27/03/2023 18:14, Sumit Gupta wrote:
> [...]
> > > diff --git a/drivers/memory/tegra/tegra186-emc.c b/drivers/memory/tegra/tegra186-emc.c
> [...]
> > > @@ -158,6 +260,9 @@ static int tegra186_emc_probe(struct platform_device *pdev)
> > >   	if (!emc)
> > >   		return -ENOMEM;
> > >   
> > > +	platform_set_drvdata(pdev, emc);
> > > +	emc->dev = &pdev->dev;
> >
> > This patch looks like stiched from two or more patches... emc->dev does
> > not look like new member of emc, thus why do you set in exisitng
> > function in this patch? Why it wasn't needed before?
>
> This looks like it may be leftover from some development. These two
> lines exist in this driver a few lines further down. Either one pair
> should be removed. I don't see why this would need to be moved, so
> probably the above additions can just be dropped.
>
> Thierry
Yes, sorry i was left over. Will remove this.
Thank you for catching.

> > >   	emc->bpmp = tegra_bpmp_get(&pdev->dev);
> > >   	if (IS_ERR(emc->bpmp))
> > >   		return dev_err_probe(&pdev->dev, PTR_ERR(emc->bpmp), "failed to get BPMP\n");
> > > @@ -236,6 +341,25 @@ static int tegra186_emc_probe(struct platform_device *pdev)
> > >   	debugfs_create_file("max_rate", S_IRUGO | S_IWUSR, emc->debugfs.root,
> > >   			    emc, &tegra186_emc_debug_max_rate_fops);
> > >   
> > > +	mc = dev_get_drvdata(emc->dev->parent);
> > > +	if (mc && mc->soc->icc_ops) {
> > > +		/*
> > > +		 * Initialize the ICC even if BPMP-FW doesn't support 'MRQ_BWMGR_INT'.
> > > +		 * Use the flag 'mc->bwmgr_mrq_supported' within MC driver and return
> > > +		 * EINVAL instead of passing the request to BPMP-FW later when the BW
> > > +		 * request is made by client with 'icc_set_bw()' call.
> > > +		 */
> > > +		err = tegra_emc_interconnect_init(emc);
> > > +		if (err)
> > > +			goto put_bpmp;
> > > +
> > > +		if (tegra_bpmp_mrq_is_supported(emc->bpmp, MRQ_BWMGR_INT))
> > > +			mc->bwmgr_mrq_supported = true;
> > > +		else
> > > +
> >
> > Drop blank line.
Ok.

> > > +			dev_info(&pdev->dev, "MRQ_BWMGR_INT not present\n");
> >
> > And what user is supposed to do with this? Either make it descriptive or
> > drop.
>
> Agreed. I think we can just drop this. If the intention was to provide a
> quick way for people to detect whether BWMGR is available or not, using
> something from sysfs/debugfs would be preferable.
>
> Thierry

Sure, will drop this.

Thank you,
Sumit Gupta