Re: [PATCH 7/7] PCI: apple: Add T602x PCIe support

[Marc Zyngier <maz@kernel.org>]

On Thu, 13 Feb 2025 17:56:19 +0000,
Rob Herring <robh@kernel.org> wrote:
> 
> On Tue, Feb 11, 2025 at 1:54 PM Alyssa Rosenzweig <alyssa@rosenzweig.io> wrote:
> >
> > From: Hector Martin <marcan@marcan.st>
> >
> > This version of the hardware moved around a bunch of registers, so we
> > drop the old compatible for these and introduce register offset
> > structures to handle the differences.
> >
> > Signed-off-by: Hector Martin <marcan@marcan.st>
> > Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
> > ---
> >  drivers/pci/controller/pcie-apple.c | 125 ++++++++++++++++++++++++++++++------
> >  1 file changed, 105 insertions(+), 20 deletions(-)
> >
> > diff --git a/drivers/pci/controller/pcie-apple.c b/drivers/pci/controller/pcie-apple.c
> > index 7f4839fb0a5b15a9ca87337f53c14a1ce08301fc..7c598334427cb56ca066890ac61143ae1d3ed744 100644
> > --- a/drivers/pci/controller/pcie-apple.c
> > +++ b/drivers/pci/controller/pcie-apple.c
> > @@ -26,6 +26,7 @@
> >  #include <linux/list.h>
> >  #include <linux/module.h>
> >  #include <linux/msi.h>
> > +#include <linux/of_device.h>
> 
> Drivers should not need this...
> 
> > +const struct reg_info t602x_hw = {
> > +       .phy_lane_ctl = 0,
> > +       .port_msiaddr = PORT_T602X_MSIADDR,
> > +       .port_msiaddr_hi = PORT_T602X_MSIADDR_HI,
> > +       .port_refclk = 0,
> > +       .port_perst = PORT_T602X_PERST,
> > +       .port_rid2sid = PORT_T602X_RID2SID,
> > +       .port_msimap = PORT_T602X_MSIMAP,
> > +       .max_rid2sid = 512, /* 16 on t602x, guess for autodetect on future HW */
> > +       .max_msimap = 512, /* 96 on t602x, guess for autodetect on future HW */
> > +};
> > +
> > +static const struct of_device_id apple_pcie_of_match_hw[] = {
> > +       { .compatible = "apple,t6020-pcie", .data = &t602x_hw },
> > +       { .compatible = "apple,pcie", .data = &t8103_hw },
> > +       { }
> > +};
> 
> You should not have 2 match tables.
> 
> > @@ -750,13 +828,19 @@ static int apple_pcie_init(struct pci_config_window *cfg)
> >         struct platform_device *platform = to_platform_device(dev);
> >         struct device_node *of_port;
> >         struct apple_pcie *pcie;
> > +       const struct of_device_id *match;
> >         int ret;
> >
> > +       match = of_match_device(apple_pcie_of_match_hw, dev);
> > +       if (!match)
> > +               return -ENODEV;
> > +
> >         pcie = devm_kzalloc(dev, sizeof(*pcie), GFP_KERNEL);
> >         if (!pcie)
> >                 return -ENOMEM;
> >
> >         pcie->dev = dev;
> > +       pcie->hw = match->data;
> >
> >         mutex_init(&pcie->lock);
> >
> > @@ -795,6 +879,7 @@ static const struct pci_ecam_ops apple_pcie_cfg_ecam_ops = {
> >  };
> >
> >  static const struct of_device_id apple_pcie_of_match[] = {
> > +       { .compatible = "apple,t6020-pcie", .data = &apple_pcie_cfg_ecam_ops },
> >         { .compatible = "apple,pcie", .data = &apple_pcie_cfg_ecam_ops },
> >         { }
> 
> You are going to need to merge the data to 1 struct.
> 
> And then use (of_)?device_get_match_data() in probe().

No, that will break the driver. This isn't a standalone driver, but
only an ECAM shim (as you can tell from the actual probe function).

	M.

-- 
Without deviation from the norm, progress is not possible.