From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Subject: Re: [PATCH v6 15/18] PCI: dwc: Make cpu_addr_fixup take struct dw_pcie as argument To: Niklas Cassel , Lorenzo Pieralisi , Bjorn Helgaas , Niklas Cassel , Jesper Nilsson , Jingoo Han , Joao Pinto References: <20171219232940.659-1-niklas.cassel@axis.com> <20171219232940.659-16-niklas.cassel@axis.com> CC: , , , From: Kishon Vijay Abraham I Message-ID: <0dc3ffca-0ca2-ed94-5e73-0dd0fcf6e973@ti.com> Date: Wed, 20 Dec 2017 11:22:10 +0530 MIME-Version: 1.0 In-Reply-To: <20171219232940.659-16-niklas.cassel@axis.com> Content-Type: text/plain; charset="windows-1252" Sender: linux-kernel-owner@vger.kernel.org List-ID: On Wednesday 20 December 2017 04:59 AM, Niklas Cassel wrote: > The current cpu addr fixup mask for ARTPEC-6, GENMASK(27, 0), is wrong. > The correct cpu addr fixup mask for ARTPEC-6 is GENMASK(28, 0). > > However, having a hardcoded cpu addr fixup mask in each driver is > arguably wrong. > A device tree property called something like "cpu-addr-fixup-mask" > would have been a better solution. > Introducing such a property is not needed though, since we already have > pp->cfg0_base and ep->phys_base, which is derived from already existing > device tree properties. > > It is also worth noting that for ARTPEC-7, hardcoding the cpu addr fixup > mask is not possible, since it uses a High Address Bits Look Up Table, > which means that it can, at runtime, map the PCIe window to an arbitrary > address in the 32-bit address space. > > By using pp->cfg0_base and ep->phys_base, we avoid hardcoding a mask > in each driver. This should work for ARTPEC-6, DRA7xx, and ARTPEC-7. > I have not changed the code in DRA7xx though, since their existing > code works, but if they want, they could use the same logic as > artpec6_pcie_cpu_addr_fixup, and thus remove their hardcoded mask. > > The reason why the fixup mask is needed is explained in commit f4c55c5a3f7f > ("PCI: designware: Program ATU with untranslated address"). > > Signed-off-by: Niklas Cassel Acked-by: Kishon Vijay Abraham I > --- > drivers/pci/dwc/pci-dra7xx.c | 2 +- > drivers/pci/dwc/pcie-artpec6.c | 18 ++++++++++++++---- > drivers/pci/dwc/pcie-designware.c | 2 +- > drivers/pci/dwc/pcie-designware.h | 2 +- > 4 files changed, 17 insertions(+), 7 deletions(-) > > diff --git a/drivers/pci/dwc/pci-dra7xx.c b/drivers/pci/dwc/pci-dra7xx.c > index 224ff8affdce..89d87844abb3 100644 > --- a/drivers/pci/dwc/pci-dra7xx.c > +++ b/drivers/pci/dwc/pci-dra7xx.c > @@ -110,7 +110,7 @@ static inline void dra7xx_pcie_writel(struct dra7xx_pcie *pcie, u32 offset, > writel(value, pcie->base + offset); > } > > -static u64 dra7xx_pcie_cpu_addr_fixup(u64 pci_addr) > +static u64 dra7xx_pcie_cpu_addr_fixup(struct dw_pcie *pci, u64 pci_addr) > { > return pci_addr & DRA7XX_CPU_TO_BUS_ADDR; > } > diff --git a/drivers/pci/dwc/pcie-artpec6.c b/drivers/pci/dwc/pcie-artpec6.c > index e7de4e4649eb..318a2bd0d97e 100644 > --- a/drivers/pci/dwc/pcie-artpec6.c > +++ b/drivers/pci/dwc/pcie-artpec6.c > @@ -67,8 +67,6 @@ static const struct of_device_id artpec6_pcie_of_match[]; > #define PHY_STATUS 0x118 > #define PHY_COSPLLLOCK BIT(0) > > -#define ARTPEC6_CPU_TO_BUS_ADDR GENMASK(27, 0) > - > static u32 artpec6_pcie_readl(struct artpec6_pcie *artpec6_pcie, u32 offset) > { > u32 val; > @@ -82,9 +80,21 @@ static void artpec6_pcie_writel(struct artpec6_pcie *artpec6_pcie, u32 offset, u > regmap_write(artpec6_pcie->regmap, offset, val); > } > > -static u64 artpec6_pcie_cpu_addr_fixup(u64 pci_addr) > +static u64 artpec6_pcie_cpu_addr_fixup(struct dw_pcie *pci, u64 pci_addr) > { > - return pci_addr & ARTPEC6_CPU_TO_BUS_ADDR; > + struct artpec6_pcie *artpec6_pcie = to_artpec6_pcie(pci); > + struct pcie_port *pp = &pci->pp; > + struct dw_pcie_ep *ep = &pci->ep; > + > + switch (artpec6_pcie->mode) { > + case DW_PCIE_RC_TYPE: > + return pci_addr - pp->cfg0_base; > + case DW_PCIE_EP_TYPE: > + return pci_addr - ep->phys_base; > + default: > + dev_err(pci->dev, "UNKNOWN device type\n"); > + } > + return pci_addr; > } > > static int artpec6_pcie_establish_link(struct dw_pcie *pci) > diff --git a/drivers/pci/dwc/pcie-designware.c b/drivers/pci/dwc/pcie-designware.c > index 88abdddee2ad..800be7a4f087 100644 > --- a/drivers/pci/dwc/pcie-designware.c > +++ b/drivers/pci/dwc/pcie-designware.c > @@ -149,7 +149,7 @@ void dw_pcie_prog_outbound_atu(struct dw_pcie *pci, int index, int type, > u32 retries, val; > > if (pci->ops->cpu_addr_fixup) > - cpu_addr = pci->ops->cpu_addr_fixup(cpu_addr); > + cpu_addr = pci->ops->cpu_addr_fixup(pci, cpu_addr); > > if (pci->iatu_unroll_enabled) { > dw_pcie_prog_outbound_atu_unroll(pci, index, type, cpu_addr, > diff --git a/drivers/pci/dwc/pcie-designware.h b/drivers/pci/dwc/pcie-designware.h > index 24edac035160..cca5a81c1c74 100644 > --- a/drivers/pci/dwc/pcie-designware.h > +++ b/drivers/pci/dwc/pcie-designware.h > @@ -205,7 +205,7 @@ struct dw_pcie_ep { > }; > > struct dw_pcie_ops { > - u64 (*cpu_addr_fixup)(u64 cpu_addr); > + u64 (*cpu_addr_fixup)(struct dw_pcie *pcie, u64 cpu_addr); > u32 (*read_dbi)(struct dw_pcie *pcie, void __iomem *base, u32 reg, > size_t size); > void (*write_dbi)(struct dw_pcie *pcie, void __iomem *base, u32 reg, >