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IOMMU and ITS use the same stream id. Check msi-map and smmu-map and make sure the same PCI bpf map to the same stream id. Then config LUT related registers. Signed-off-by: Frank Li --- drivers/pci/controller/dwc/pci-imx.c | 175 +++++++++++++++++++++++++++++++++++ 1 file changed, 175 insertions(+) diff --git a/drivers/pci/controller/dwc/pci-imx.c b/drivers/pci/controller/dwc/pci-imx.c index 460d40115935b..782555beb6e9d 100644 --- a/drivers/pci/controller/dwc/pci-imx.c +++ b/drivers/pci/controller/dwc/pci-imx.c @@ -55,6 +55,22 @@ #define IMX95_PE0_GEN_CTRL_3 0x1058 #define IMX95_PCIE_LTSSM_EN BIT(0) +#define IMX95_PE0_LUT_ACSCTRL 0x1008 +#define IMX95_PEO_LUT_RWA BIT(16) +#define IMX95_PE0_LUT_ENLOC GENMASK(4, 0) + +#define IMX95_PE0_LUT_DATA1 0x100c +#define IMX95_PE0_LUT_VLD BIT(31) +#define IMX95_PE0_LUT_DAC_ID GENMASK(10, 8) +#define IMX95_PE0_LUT_STREAM_ID GENMASK(5, 0) + +#define IMX95_PE0_LUT_DATA2 0x1010 +#define IMX95_PE0_LUT_REQID GENMASK(31, 16) +#define IMX95_PE0_LUT_MASK GENMASK(15, 0) + +#define IMX95_SID_MASK GENMASK(5, 0) +#define IMX95_MAX_LUT 32 + #define to_imx_pcie(x) dev_get_drvdata((x)->dev) enum imx_pcie_variants { @@ -217,6 +233,159 @@ static int imx95_pcie_init_phy(struct imx_pcie *imx_pcie) return 0; } +static int imx_pcie_update_lut(struct imx_pcie *imx_pcie, int index, u16 reqid, u16 mask, u8 sid) +{ + struct dw_pcie *pci = imx_pcie->pci; + struct device *dev = pci->dev; + u32 data1, data2; + + if (sid >= 64) { + dev_err(dev, "Too big stream id: %d\n", sid); + return -EINVAL; + } + + data1 = FIELD_PREP(IMX95_PE0_LUT_DAC_ID, 0); + data1 |= FIELD_PREP(IMX95_PE0_LUT_STREAM_ID, sid); + data1 |= IMX95_PE0_LUT_VLD; + + regmap_write(imx_pcie->iomuxc_gpr, IMX95_PE0_LUT_DATA1, data1); + + data2 = mask; + data2 |= FIELD_PREP(IMX95_PE0_LUT_REQID, reqid); + + regmap_write(imx_pcie->iomuxc_gpr, IMX95_PE0_LUT_DATA2, data2); + + regmap_write(imx_pcie->iomuxc_gpr, IMX95_PE0_LUT_ACSCTRL, index); + + return 0; +} + +struct imx_of_map { + u32 bdf; + u32 phandle; + u32 sid; + u32 sid_len; +}; + +static int imx_check_msi_and_smmmu(struct imx_pcie *imx_pcie, + struct imx_of_map *msi_map, u32 msi_size, u32 msi_map_mask, + struct imx_of_map *smmu_map, u32 smmu_size, u32 smmu_map_mask) +{ + struct dw_pcie *pci = imx_pcie->pci; + struct device *dev = pci->dev; + int i; + + if (msi_map && smmu_map) { + if (msi_size != smmu_size) + return -EINVAL; + if (msi_map_mask != smmu_map_mask) + return -EINVAL; + + for (i = 0; i < msi_size / sizeof(*msi_map); i++) { + if (msi_map->bdf != smmu_map->bdf) { + dev_err(dev, "bdf setting is not match\n"); + return -EINVAL; + } + if ((msi_map->sid & IMX95_SID_MASK) != smmu_map->sid) { + dev_err(dev, "sid setting is not match\n"); + return -EINVAL; + } + if ((msi_map->sid_len & IMX95_SID_MASK) != smmu_map->sid_len) { + dev_err(dev, "sid_len setting is not match\n"); + return -EINVAL; + } + } + } + + return 0; +} + +/* + * Simple static config lut according to dts settings DAC index and stream ID used as a match result + * of LUT pre-allocated and used by PCIes. + * + * Currently stream ID from 32-64 for PCIe. + * 32-40: first PCI bus. + * 40-48: second PCI bus. + * + * DAC_ID is index of TRDC.DAC index, start from 2 at iMX95. + * ITS [pci(2bit): streamid(6bits)] + * pci 0 is 0 + * pci 1 is 3 + */ +static int imx_pcie_config_sid(struct imx_pcie *imx_pcie) +{ + struct imx_of_map *msi_map = NULL, *smmu_map = NULL, *cur; + int i, j, lut_index, nr_map, msi_size = 0, smmu_size = 0; + u32 msi_map_mask = 0xffff, smmu_map_mask = 0xffff; + struct dw_pcie *pci = imx_pcie->pci; + struct device *dev = pci->dev; + u32 mask; + int size; + + of_get_property(dev->of_node, "msi-map", &msi_size); + if (msi_size) { + msi_map = devm_kzalloc(dev, msi_size, GFP_KERNEL); + if (!msi_map) + return -ENOMEM; + + if (of_property_read_u32_array(dev->of_node, "msi-map", (u32 *)msi_map, + msi_size / sizeof(u32))) + return -EINVAL; + + of_property_read_u32(dev->of_node, "msi-map-mask", &msi_map_mask); + } + + cur = msi_map; + size = msi_size; + mask = msi_map_mask; + + of_get_property(dev->of_node, "iommu-map", &smmu_size); + if (smmu_size) { + smmu_map = devm_kzalloc(dev, smmu_size, GFP_KERNEL); + if (!smmu_map) + return -ENOMEM; + + if (of_property_read_u32_array(dev->of_node, "iommu-map", (u32 *)smmu_map, + smmu_size / sizeof(u32))) + return -EINVAL; + + of_property_read_u32(dev->of_node, "smmu_map_mask", &smmu_map_mask); + } + + if (imx_check_msi_and_smmmu(imx_pcie, msi_map, msi_size, msi_map_mask, + smmu_map, smmu_size, smmu_map_mask)) + return -EINVAL; + + if (!cur) { + cur = smmu_map; + size = smmu_size; + mask = smmu_map_mask; + } + + nr_map = size / (sizeof(*cur)); + + lut_index = 0; + for (i = 0; i < nr_map; i++) { + for (j = 0; j < cur->sid_len; j++) { + imx_pcie_update_lut(imx_pcie, lut_index, cur->bdf + j, mask, + (cur->sid + j) & IMX95_SID_MASK); + lut_index++; + } + cur++; + + if (lut_index >= IMX95_MAX_LUT) { + dev_err(dev, "its-map/iommu-map exceed HW limiation\n"); + return -EINVAL; + } + } + + devm_kfree(dev, smmu_map); + devm_kfree(dev, msi_map); + + return 0; +} + static void imx_pcie_configure_type(struct imx_pcie *imx_pcie) { const struct imx_pcie_drvdata *drvdata = imx_pcie->drvdata; @@ -950,6 +1119,12 @@ static int imx_pcie_host_init(struct dw_pcie_rp *pp) goto err_phy_off; } + ret = imx_pcie_config_sid(imx_pcie); + if (ret < 0) { + dev_err(dev, "failed to config sid:%d\n", ret); + goto err_phy_off; + } + imx_setup_phy_mpll(imx_pcie); return 0;