Hi Kishon, On Wed, Mar 2, 2022 at 6:28 PM Frank Li <frank.li@xxxxxxx> wrote: > > > > > -----Original Message----- > > From: Lad, Prabhakar <prabhakar.csengg@xxxxxxxxx> > > Sent: Wednesday, March 2, 2022 11:18 AM > > To: Frank Li <frank.li@xxxxxxx> > > Cc: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>; Lad Prabhakar > > <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>; Kishon Vijay Abraham I > > <kishon@xxxxxx>; Bjorn Helgaas <bhelgaas@xxxxxxxxxx>; Lorenzo Pieralisi > > <lorenzo.pieralisi@xxxxxxx>; Krzysztof Wilczyński <kw@xxxxxxxxx>; Arnd > > Bergmann <arnd@xxxxxxxx>; Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>; > > Marek Vasut <marek.vasut+renesas@xxxxxxxxx>; Yoshihiro Shimoda > > <yoshihiro.shimoda.uh@xxxxxxxxxxx>; Rob Herring <robh@xxxxxxxxxx>; linux- > > pci <linux-pci@xxxxxxxxxxxxxxx>; Linux-Renesas <linux-renesas- > > soc@xxxxxxxxxxxxxxx>; LKML <linux-kernel@xxxxxxxxxxxxxxx>; Biju Das > > <biju.das.jz@xxxxxxxxxxxxxx> > > Subject: [EXT] Re: [RFC PATCH 0/5] PCIe EPF support for internal DMAC > > handling and driver update for R-Car PCIe EP to support DMAC > > > > Caution: EXT Email > > > > Hi Frank, > > > > On Wed, Mar 2, 2022 at 3:42 PM Frank Li <frank.li@xxxxxxx> wrote: > > > > > > > > > > > > > -----Original Message----- > > > > From: Lad, Prabhakar <prabhakar.csengg@xxxxxxxxx> > > > > Sent: Thursday, February 10, 2022 3:24 AM > > > > To: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx> > > > > Cc: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>; Kishon > > Vijay > > > > Abraham I <kishon@xxxxxx>; Bjorn Helgaas <bhelgaas@xxxxxxxxxx>; Lorenzo > > > > Pieralisi <lorenzo.pieralisi@xxxxxxx>; Krzysztof Wilczyński > > <kw@xxxxxxxxx>; > > > > Arnd Bergmann <arnd@xxxxxxxx>; Greg Kroah-Hartman > > > > <gregkh@xxxxxxxxxxxxxxxxxxx>; Marek Vasut > > <marek.vasut+renesas@xxxxxxxxx>; > > > > Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>; Rob Herring > > > > <robh@xxxxxxxxxx>; linux-pci <linux-pci@xxxxxxxxxxxxxxx>; Linux-Renesas > > > > <linux-renesas-soc@xxxxxxxxxxxxxxx>; LKML <linux- > > kernel@xxxxxxxxxxxxxxx>; > > > > Biju Das <biju.das.jz@xxxxxxxxxxxxxx> > > > > Subject: [EXT] Re: [RFC PATCH 0/5] PCIe EPF support for internal DMAC > > > > handling and driver update for R-Car PCIe EP to support DMAC > > > > > > I use standard DMA engine API to implement Designware PCIE EP embedded > > DMA support. > > > Please check > > https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Flore.kern > > el.org%2Fall%2F20220302032646.3793-3- > > Frank.Li%40nxp.com%2FT%2F&data=04%7C01%7Cfrank.li%40nxp.com%7C0e2e5fe8f > > d224076afb208d9fc70aa16%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C637818 > > 383096028914%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLC > > JBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000&sdata=DCDX%2BYEVFsPOE6ZWzwrMxk1Fjlk > > ZA%2FEPGmhQSHuPB2c%3D&reserved=0 > > > > > Thank you for the link. The Designware PCIE EP is implemented as a DMA > > engine driver so it's convenient to use the DMA engine API, whereas > > the R-Car PCIe-EP is implemented as an actual PCIe EP [0]. > > My means, needn't add new interface pci_epf_internal_dmac_xfr at epc/epf. > Your R-Car PCI-EP DMA part can implement as a dma engine driver like designware. > > So EP functional driver use the same method to operate DMA regardless > EP controller type. > With this approach all the PCIe controllers supporting internal dmac will have to be added as a DMA driver. Could you please provide some feedback on the above? Sorry this mail is not in chain to my orignal patch series. My orignal series can be found at [0] [0] https://patchwork.kernel.org/project/linux-renesas-soc/cover/20220126195043.28376-1-prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx/ Cheers, Prabhakar
