Re: [PATCH 7/7] PCI: dwc: qcom: Add support for IPQ8074 PCIe controller

From: Bjorn Andersson
Date: Tue Jul 18 2017 - 12:44:48 EST


On Tue 18 Jul 02:58 PDT 2017, Varadarajan Narayanan wrote:

> On Mon, Jul 17, 2017 at 03:07:18PM -0700, Bjorn Andersson wrote:
> > On Mon 17 Jul 05:04 PDT 2017, Varadarajan Narayanan wrote:
[..]
> >
> > Can you confirm that this is actually version 4 of this block? Or are we
> > just incrementing an arbitrary number here?
>
> This is not exactly the 4th version of the block. However, it is
> a different version than the ones that are already supported in
> this driver. Since the existing driver didn't exactly tie it with
> the block IP version, I too followed the same versioning
> convention.
>

Do you have a block IP version that you could base your numbering on, to
break the trend? (We should go back and fix up the others as well)

[..]
> > > +static int qcom_pcie_enable_resources_v4(struct qcom_pcie *pcie)
> > > +{
> > > + struct qcom_pcie_resources_v4 *res = &pcie->res.v4;
> > > + struct dw_pcie *pci = pcie->pci;
> > > + struct device *dev = pci->dev;
> > > + int ret;
> > > +
> > > + ret = clk_prepare_enable(res->sys_noc_clk);
> > > + if (ret) {
> > > + dev_err(dev, "cannot prepare/enable core clock\n");
> > > + return ret;
> > > + }
> >
> > Should these clocks really be handled explicitly in the driver? Are
> > these not the bus clocks, to be handled by "msm_bus"?
>
> This not the bus clock. This clock is for the Bus Interface Unit
> between the PCIe module and the System NOC.
>

Right, that was the piece I meant. Sorry for not using the right
nomenclature.

So then it would be handled by the msm_bus in the downstream kernel?


Perhaps we can merge it like this and once we have the interconnect
framework setup we can make this the fallback method.

Thanks,
Bjorn