dm: pci: Add a function to read a PCI BAR

At present PCI address transaction is not supported so drivers must
manually read the correct BAR after reading the device tree info. The
ns16550 has a suitable implementation, so move this code into the core
DM support.

Note that there is no live-tree equivalent at present.

Signed-off-by: Simon Glass <[email protected]>
Reviewed-by: Bin Meng <[email protected]>
Tested-by: Bin Meng <[email protected]>
[bmeng: correct the unclear comments in test.dts]
Signed-off-by: Bin Meng <[email protected]>

3 files changed, 45 insertions, 30 deletions

diff --git a/drivers/core/fdtaddr.c b/drivers/core/fdtaddr.c
index 6850003a287..c9a941116a3 100644
--- a/drivers/core/fdtaddr.c
+++ b/drivers/core/fdtaddr.c
@@ -190,3 +190,36 @@ void *devfdt_map_physmem(struct udevice *dev, unsigned long size)
 
 	return map_physmem(addr, size, MAP_NOCACHE);
 }
+
+fdt_addr_t devfdt_get_addr_pci(struct udevice *dev)
+{
+	ulong addr;
+
+	addr = devfdt_get_addr(dev);
+	if (CONFIG_IS_ENABLED(PCI) && IS_ENABLED(CONFIG_DM_PCI) &&
+	    addr == FDT_ADDR_T_NONE) {
+		struct fdt_pci_addr pci_addr;
+		u32 bar;
+		int ret;
+
+		ret = fdtdec_get_pci_addr(gd->fdt_blob,
+					  dev_of_offset(dev),
+					  FDT_PCI_SPACE_MEM32, "reg",
+					  &pci_addr);
+		if (ret) {
+			/* try if there is any i/o-mapped register */
+			ret = fdtdec_get_pci_addr(gd->fdt_blob,
+						  dev_of_offset(dev),
+						  FDT_PCI_SPACE_IO, "reg",
+						  &pci_addr);
+			if (ret)
+				return FDT_ADDR_T_NONE;
+		}
+		ret = fdtdec_get_pci_bar32(dev, &pci_addr, &bar);
+		if (ret)
+			return FDT_ADDR_T_NONE;
+		addr = bar;
+	}
+
+	return addr;
+}
diff --git a/drivers/core/read.c b/drivers/core/read.c
index fb3dcd9a790..9602e52d1b1 100644
--- a/drivers/core/read.c
+++ b/drivers/core/read.c
@@ -307,3 +307,14 @@ int dev_read_alias_highest_id(const char *stem)
 
 	return fdtdec_get_alias_highest_id(gd->fdt_blob, stem);
 }
+
+fdt_addr_t dev_read_addr_pci(struct udevice *dev)
+{
+	ulong addr;
+
+	addr = dev_read_addr(dev);
+	if (addr == FDT_ADDR_T_NONE && !of_live_active())
+		addr = devfdt_get_addr_pci(dev);
+
+	return addr;
+}
diff --git a/drivers/serial/ns16550.c b/drivers/serial/ns16550.c
index 01f334938ea..754b6e99215 100644
--- a/drivers/serial/ns16550.c
+++ b/drivers/serial/ns16550.c
@@ -440,36 +440,7 @@ int ns16550_serial_ofdata_to_platdata(struct udevice *dev)
 	int err;
 
 	/* try Processor Local Bus device first */
-	addr = dev_read_addr(dev);
-#if CONFIG_IS_ENABLED(PCI) && defined(CONFIG_DM_PCI)
-	if (addr == FDT_ADDR_T_NONE) {
-		/* then try pci device */
-		struct fdt_pci_addr pci_addr;
-		u32 bar;
-		int ret;
-
-		/* we prefer to use a memory-mapped register */
-		ret = fdtdec_get_pci_addr(gd->fdt_blob, dev_of_offset(dev),
-					  FDT_PCI_SPACE_MEM32, "reg",
-					  &pci_addr);
-		if (ret) {
-			/* try if there is any i/o-mapped register */
-			ret = fdtdec_get_pci_addr(gd->fdt_blob,
-						  dev_of_offset(dev),
-						  FDT_PCI_SPACE_IO,
-						  "reg", &pci_addr);
-			if (ret)
-				return ret;
-		}
-
-		ret = fdtdec_get_pci_bar32(dev, &pci_addr, &bar);
-		if (ret)
-			return ret;
-
-		addr = bar;
-	}
-#endif
-
+	addr = dev_read_addr_pci(dev);
 	if (addr == FDT_ADDR_T_NONE)
 		return -EINVAL;