Hi Marc,
Please see my comments inline.
Thanks,
Minghaun
> -----Original Message-----
> From: Marc Zyngier [mailto:[email protected]]
> Sent: Monday, February 29, 2016 6:14 PM
> To: Minghuan Lian <[email protected]>;
> [email protected]
> Cc: Thomas Gleixner <[email protected]>; Jason Cooper
> <[email protected]>; Roy Zang <[email protected]>; Mingkai Hu
> <[email protected]>; Stuart Yoder <[email protected]>; Yang-Leo Li
> <[email protected]>; [email protected]
> Subject: Re: [PATCH 2/2 v3] irqchip/Layerscape: Add SCFG MSI controller
> support
>
> On 25/02/16 03:21, Minghuan Lian wrote:
> > Hi Marc,
> >
> > I am sorry for the delayed response due to the Chinese Spring Festival holiday.
> > Thank you very much for the review.
> > Please see my comments inline.
> >
> > Thanks,
> > Minghuan
> >
>
> [...]
>
> >>> +static int ls_scfg_msi_probe(struct platform_device *pdev) {
> >>> + struct ls_scfg_msi *msi_data;
> >>> + struct resource *res;
> >>> + int ret;
> >>> +
> >>> + msi_data = devm_kzalloc(&pdev->dev, sizeof(*msi_data),
> GFP_KERNEL);
> >>> + if (!msi_data)
> >>> + return -ENOMEM;
> >>> +
> >>> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> >>> + msi_data->regs = devm_ioremap_resource(&pdev->dev, res);
> >>> + if (IS_ERR(msi_data->regs)) {
> >>> + dev_err(&pdev->dev, "failed to initialize 'regs'\n");
> >>> + return PTR_ERR(msi_data->regs);
> >>> + }
> >>> + msi_data->msiir_addr = res->start;
> >>> +
> >>> + msi_data->irq = platform_get_irq(pdev, 0);
> >>> + if (msi_data->irq <= 0) {
> >>> + dev_err(&pdev->dev, "failed to get MSI irq\n");
> >>> + return -ENODEV;
> >>> + }
> >>> +
> >>> + msi_data->pdev = pdev;
> >>> + msi_data->nr_irqs = MSI_MAX_IRQS;
> >>
> >> So this is hardcoded, always. Why do you need a nr_irqs variable at all?
> > [Lian Minghuan-B31939] Currently, nr_irqs is always 32, but in the
> > future, the MSI controller may be extended to support more IRQs. And,
> > we may set nr_irqs the value of less than 32 to reserve some IRQs for
> > special usage. So nr_irqs can bring flexibility
>
> You have to choose: either this is configurable and you describe it in
> DT, or this is not and you drop this field from the structure.
>
> As for the "reserved interrupts", that would need to be described too.
>
[Minghuan Lian] I will drop this field in next version.
The old version of LS1021a only supports one MSI interrupt. So the driver needs to change nr_irq to 1.
Anyway, this issue has been fixed. Now, all the Layerscape SoC supports 32 MSI interrupts.
> Thanks,
>
> M.
> --
> Jazz is not dead. It just smells funny...