[PATCH v3 08/11] PCI: imx: Config look up table(LUT) to support MSI ITS and IOMMU for i.MX95

From: Frank Li
Date: Tue Apr 02 2024 - 10:37:23 EST


i.MX95 need config LUT to convert bpf to stream id. 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 <Frank.Li@xxxxxxx>
---
drivers/pci/controller/dwc/pcie-imx.c | 175 ++++++++++++++++++++++++++++++++++
1 file changed, 175 insertions(+)

diff --git a/drivers/pci/controller/dwc/pcie-imx.c b/drivers/pci/controller/dwc/pcie-imx.c
index af0f960f28757..653d8e8ee1abc 100644
--- a/drivers/pci/controller/dwc/pcie-imx.c
+++ b/drivers/pci/controller/dwc/pcie-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, "iommu_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;

--
2.34.1