[U-Boot] [PATCH 5/5 v6] pci/layerscape: set LUT and msi-map for discovered PCI devices

[Stuart Yoder]

From: Stuart Yoder <stuart.yoder at nxp.com>

msi-map properties are used to tell an OS how PCI requester IDs are
mapped to ARM SMMU stream IDs.

for all PCI devices discovered in a system:
  -allocate a LUT (look-up-table) entry in that PCI controller
  -allocate a stream ID for the device
  -program and enable a LUT entry (maps PCI requester id to stream ID)
  -set the msi-map property on the controller reflecting the
   LUT mapping

basic bus scanning loop/logic was taken from drivers/pci/pci.c
pci_hose_scan_bus().

Signed-off-by: Stuart Yoder <stuart.yoder at nxp.com>
---
-v6: squashed lut, stream id, and msi-map helper functions
     (previously patches 4-6) into this patch

 drivers/pci/pcie_layerscape.c |  147 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 147 insertions(+)

diff --git a/drivers/pci/pcie_layerscape.c b/drivers/pci/pcie_layerscape.c
index bb29222..0ba960e 100644
--- a/drivers/pci/pcie_layerscape.c
+++ b/drivers/pci/pcie_layerscape.c
@@ -93,6 +93,7 @@ struct ls_pcie {
 	void __iomem *dbi;
 	void __iomem *va_cfg0;
 	void __iomem *va_cfg1;
+	int next_lut_index;
 	struct pci_controller hose;
 };
 
@@ -482,6 +483,147 @@ static void ls_pcie_setup_ep(struct ls_pcie *pcie, struct ls_pcie_info *info)
 	}
 }
 
+#ifdef CONFIG_FSL_LSCH3
+/*
+ * Return next available LUT index.
+ */
+static int ls_pcie_next_lut_index(struct ls_pcie *pcie)
+{
+	if (pcie->next_lut_index < PCIE_LUT_ENTRY_COUNT)
+		return pcie->next_lut_index++;
+	else
+		return -1;  /* LUT is full */
+}
+
+/*
+ * Program a single LUT entry
+ */
+static void ls_pcie_lut_set_mapping(struct ls_pcie *pcie, int index, u32 devid,
+			     u32 streamid)
+{
+	void __iomem *lut;
+
+	lut = pcie->dbi + PCIE_LUT_BASE;
+
+	/* leave mask as all zeroes, want to match all bits */
+	writel((devid << 16), lut + PCIE_LUT_UDR(index));
+	writel(streamid | PCIE_LUT_ENABLE, lut + PCIE_LUT_LDR(index));
+}
+
+/* returns the next available streamid */
+static u32 ls_pcie_next_streamid(void)
+{
+	static int next_stream_id = FSL_PEX_STREAM_ID_START;
+
+	if (next_stream_id > FSL_PEX_STREAM_ID_END)
+		return 0xffffffff;
+
+	return next_stream_id++;
+}
+
+/*
+ * An msi-map is a property to be added to the pci controller
+ * node.  It is a table, where each entry consists of 4 fields
+ * e.g.:
+ *
+ *      msi-map = <[devid] [phandle-to-msi-ctrl] [stream-id] [count]
+ *                 [devid] [phandle-to-msi-ctrl] [stream-id] [count]>;
+ */
+static void fdt_pcie_set_msi_map_entry(void *blob, struct ls_pcie *pcie,
+				       u32 devid, u32 streamid)
+{
+	char pcie_path[19];
+	u32 *prop;
+	u32 phandle;
+	int nodeoffset;
+
+	/* find pci controller node */
+	snprintf(pcie_path, sizeof(pcie_path), "/soc/pcie@%llx",
+		 (u64)pcie->dbi);
+	nodeoffset = fdt_path_offset(blob, pcie_path);
+	if (nodeoffset < 0) {
+		printf("\n%s: ERROR: unable to update PCIe node: %s\n",
+		       __func__, pcie_path);
+		return;
+	}
+
+	/* get phandle to MSI controller */
+	prop = (u32 *)fdt_getprop(blob, nodeoffset, "msi-parent", 0);
+	if (prop == NULL) {
+		printf("\n%s: ERROR: missing msi-parent: %s\n", __func__,
+		       pcie_path);
+		return;
+	}
+	phandle = be32_to_cpu(*prop);
+
+	/* set one msi-map row */
+	fdt_appendprop_u32(blob, nodeoffset, "msi-map", devid);
+	fdt_appendprop_u32(blob, nodeoffset, "msi-map", phandle);
+	fdt_appendprop_u32(blob, nodeoffset, "msi-map", streamid);
+	fdt_appendprop_u32(blob, nodeoffset, "msi-map", 1);
+}
+
+static void fdt_fixup_pcie(void *blob)
+{
+	unsigned int found_multi = 0;
+	unsigned char header_type;
+	int index;
+	u32 streamid;
+	pci_dev_t dev;
+	int bus;
+	unsigned short id;
+	struct pci_controller *hose;
+	struct ls_pcie *pcie;
+	int i;
+
+	for (i = 0, hose = pci_get_hose_head(); hose; hose = hose->next, i++) {
+		pcie = hose->priv_data;
+		for (bus = hose->first_busno; bus <= hose->last_busno; bus++) {
+
+			for (dev =  PCI_BDF(bus, 0, 0);
+			     dev <  PCI_BDF(bus, PCI_MAX_PCI_DEVICES - 1,
+					    PCI_MAX_PCI_FUNCTIONS - 1);
+			     dev += PCI_BDF(0, 0, 1)) {
+
+				if (PCI_FUNC(dev) && !found_multi)
+					continue;
+
+				pci_read_config_word(dev, PCI_VENDOR_ID, &id);
+
+				pci_read_config_byte(dev, PCI_HEADER_TYPE,
+						     &header_type);
+
+				if ((id == 0xFFFF) || (id == 0x0000))
+					continue;
+
+				if (!PCI_FUNC(dev))
+					found_multi = header_type & 0x80;
+
+				streamid = ls_pcie_next_streamid();
+				if (streamid == 0xffffffff) {
+					printf("ERROR: no stream ids free\n");
+					continue;
+				}
+
+				index = ls_pcie_next_lut_index(pcie);
+				if (index < 0) {
+					printf("ERROR: no LUT indexes free\n");
+					continue;
+				}
+
+				/* map PCI b.d.f to streamID in LUT */
+				ls_pcie_lut_set_mapping(pcie, index, dev >> 8,
+							streamid);
+
+				/* update msi-map in device tree */
+				fdt_pcie_set_msi_map_entry(blob, pcie, dev >> 8,
+							   streamid);
+			}
+		}
+	}
+}
+#endif
+
 int ls_pcie_init_ctrl(int busno, enum srds_prtcl dev, struct ls_pcie_info *info)
 {
 	struct ls_pcie *pcie;
@@ -513,6 +655,7 @@ int ls_pcie_init_ctrl(int busno, enum srds_prtcl dev, struct ls_pcie_info *info)
 	pcie->va_cfg1 = map_physmem(info->cfg1_phys,
 				    info->cfg1_size,
 				    MAP_NOCACHE);
+	pcie->next_lut_index = 0;
 
 	/* outbound memory */
 	pci_set_region(&hose->regions[0],
@@ -657,6 +800,10 @@ void ft_pci_setup(void *blob, bd_t *bd)
 	#ifdef CONFIG_PCIE4
 	ft_pcie_ls_setup(blob, FSL_PCIE_COMPAT, CONFIG_SYS_PCIE4_ADDR, PCIE4);
 	#endif
+
+	#ifdef CONFIG_FSL_LSCH3
+	fdt_fixup_pcie(blob);
+	#endif
 }
 
 #else
-- 
1.7.9.5