Subject: Re: [PATCH v8 06/10] PCI: dwc: ep: Call dw_pcie_ep_init_registers() API directly from all glue drivers

From: Manivannan Sadhasivam <[email-masked]>
Date: Tue, 27 Feb 2024 17:51:41 +0530

On Mon, Feb 26, 2024 at 12:04:33PM -0500, Frank Li wrote:
> On Sat, Feb 24, 2024 at 12:24:12PM +0530, Manivannan Sadhasivam wrote:
> > Currently, dw_pcie_ep_init_registers() API is directly called by the glue
> > drivers requiring active refclk from host. But for the other drivers, it is
> > getting called implicitly by dw_pcie_ep_init(). This is due to the fact
> > that this API initializes DWC EP specific registers and that requires an
> > active refclk (either from host or generated locally by endpoint itsef).
> > 
> > But, this causes a discrepancy among the glue drivers. So to avoid this
> > confusion, let's call this API directly from all glue drivers irrespective
> > of refclk dependency. Only difference here is that the drivers requiring
> > refclk from host will call this API only after the refclk is received and
> > other drivers without refclk dependency will call this API right after
> > dw_pcie_ep_init().
> > 
> > This change will also allow us to remove the "core_init_notifier" flag in
> > the later commits.
> > 
> > Signed-off-by: Manivannan Sadhasivam <[email-masked]>
> > ---
> >  drivers/pci/controller/dwc/pci-dra7xx.c           |  7 +++++++
> >  drivers/pci/controller/dwc/pci-imx6.c             |  8 ++++++++
> >  drivers/pci/controller/dwc/pci-keystone.c         |  9 +++++++++
> >  drivers/pci/controller/dwc/pci-layerscape-ep.c    |  7 +++++++
> >  drivers/pci/controller/dwc/pcie-designware-ep.c   | 22 ----------------------
> >  drivers/pci/controller/dwc/pcie-designware-plat.c |  9 +++++++++
> >  drivers/pci/controller/dwc/pcie-rcar-gen4.c       | 12 +++++++++++-
> >  drivers/pci/controller/dwc/pcie-uniphier-ep.c     | 13 ++++++++++++-
> >  8 files changed, 63 insertions(+), 24 deletions(-)

[...]

> > diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
> > index ed1f2afd830a..278bdc9b2269 100644
> > --- a/drivers/pci/controller/dwc/pcie-designware-ep.c
> > +++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
> > @@ -729,7 +729,6 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep)
> >  	struct device *dev = pci->dev;
> >  	struct platform_device *pdev = to_platform_device(dev);
> >  	struct device_node *np = dev->of_node;
> > -	const struct pci_epc_features *epc_features;
> >  
> >  	INIT_LIST_HEAD(&ep->func_list);
> >  
> > @@ -775,29 +774,8 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep)
> >  		goto err_exit_epc_mem;
> >  	}
> >  
> > -	if (ep->ops->get_features) {
> > -		epc_features = ep->ops->get_features(ep);
> > -		if (epc_features->core_init_notifier)
> > -			return 0;
> > -	}
> 
> why remove this check?
> 

There is no point in keeping this check since we are removing the call to
dw_pcie_ep_init_registers() below. But I should've described this change in the
commit message.

- Mani

-- 
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