Re: [PATCH v3 v3] PCI: dwc: Add pci id for LECARC pcie pmu

[Manivannan Sadhasivam]

On Mon, Jul 20, 2026 at 03:43:15PM +0800, Braden Zhang wrote:
> On Mon, Jul 13, 2026 at 07:14:25AM +0200, Manivannan Sadhasivam wrote:
> > Date: Mon, 13 Jul 2026 07:14:25 +0200
> > From: Manivannan Sadhasivam <mani@xxxxxxxxxx>
> > To: Braden Zhang <braden_zhang@xxxxxxxxxxxxxxx>
> > Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>, Jingoo Han <jingoohan1@xxxxxxxxx>,
> >  linux-pci@xxxxxxxxxxxxxxx, linux-kernel@xxxxxxxxxxxxxxx, Brett Zhou
> >  <brett_zhou@xxxxxxxxxxxxxxx>, Bjorn Helgaas <helgaas@xxxxxxxxxx>
> > Subject: Re: [PATCH v3 v3] PCI: dwc: Add pci id for LECARC pcie pmu
> > 
> > On Mon, Jul 13, 2026 at 10:10:13AM +0800, Braden Zhang wrote:
> > > From: Brett Zhou <brett_zhou@xxxxxxxxxxxxxxx>
> > > 
> > > This patch adds support for the PCIe PMU found
> > > on LECARC SoCs, which utilize the DesignWare PCIe Controller IP
> > > 
> > 
> > LECARC looks like a ACPI based platform. I'm wondering how you are able to make
> > use of this patch without adding the ACPI ID support to enumerate the DWC
> > driver.
> > 
> > - Mani
> > 
> > > Signed-off-by: Brett Zhou <brett_zhou@xxxxxxxxxxxxxxx>
> > > Reviewed-by: Bjorn Helgaas <helgaas@xxxxxxxxxx>
> > > Signed-off-by: Braden Zhang <braden_zhang@xxxxxxxxxxxxxxx>
> > > ---
> > > 
> > > ---
> > > base-commit: a635d6748234582ea287c5ffeae28b9b23f91c7e
> > > change-id: 20260710-pcie-pmu-5ef78c56c3b6
> > > 
> > > Best regards,
> > > --  
> > > Braden Zhang <braden_zhang@xxxxxxxxxxxxxxx>
> > > 
> > 
> > -- 
> Hi Mani,
> 
> Thanks for the review.
> 
> LECARC platforms use the standard DesignWare PCIe Controller, and the
> existing DWC driver already handles the enumeration and basic
> functionality through the generic PCIe core.
> This patch only adds the
> PCI vendor ID to the vendor-specific capability (VSEC) list, which
> enables the standard DWC RAS/DES feature detection.
> 
> We don't require a separate PMU driver or additional ACPI ID support
> because the PMU functionality is already covered by the generic DWC
> PMU framework. The existing driver infrastructure handles the PMU
> features transparently once the vendor ID is recognized in the VSEC
> table.
> 

Ah, makes sense now. It didn't occur to me that 'dwc_pcie_rasdes_vsec_ids'
struct array is used by the PMU driver also.

Please incorporate comments from Bjorn and resend.

- Mani

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