core: ofnode: Fix translation for #size-cells == 0

Commit 286ede6 ("drivers: core: Add translation in live tree case") made
dev_get_addr always use proper bus translations for addresses read from
the device tree. But this leads to problems with certain busses, e.g.
I2C busses, which run into an error during translation, and hence stop
working.

It turns out that of_translate_address() and fdt_translate_address()
stop the address translation with an error when they're asked to
translate addresses for busses where #size-cells == 0 (comment from
drivers/core/of_addr.c):

 * Note: We consider that crossing any level with #size-cells == 0 to mean
 * that translation is impossible (that is we are not dealing with a value
 * that can be mapped to a cpu physical address). This is not really specified
 * that way, but this is traditionally the way IBM at least do things

To fix this case, we check in both the live-tree and non-live tree-case,
whether the bus of the device whose address is about to be translated
has size-cell size zero. If this is the case, we just read the address
as a plain integer and return it, and only apply bus translations if the
size-cell size if greater than zero.

Signed-off-by: Mario Six <mario.six@gdsys.cc>
Signed-off-by: Martin Fuzzey <mfuzzey@parkeon.com>
Reported-by: Martin Fuzzey <mfuzzey@parkeon.com>
Fixes: 286ede6 ("drivers: core: Add translation in live tree case")
Reviewed-by: Simon Glass <sjg@chromium.org>

arch/sandbox/dts/test.dts

@@ -27,6 +27,10 @@
 		testfdt3 = "/b-test";
 		testfdt5 = "/some-bus/c-test@5";
 		testfdt8 = "/a-test";
+		fdt_dummy0 = "/translation-test@8000/dev@0,0";
+		fdt_dummy1 = "/translation-test@8000/dev@1,100";
+		fdt_dummy2 = "/translation-test@8000/dev@2,200";
+		fdt_dummy3 = "/translation-test@8000/noxlatebus@3,300/dev@42";
 		usb0 = &usb_0;
 		usb1 = &usb_1;
 		usb2 = &usb_2;
@@ -487,6 +491,50 @@
 			reg = <9 1>;
 		};
 	};
+
+	translation-test@8000 {
+		compatible = "simple-bus";
+		reg = <0x8000 0x4000>;
+
+		#address-cells = <0x2>;
+		#size-cells = <0x1>;
+
+		ranges = <0 0x0 0x8000 0x1000
+			  1 0x100 0x9000 0x1000
+			  2 0x200 0xA000 0x1000
+			  3 0x300 0xB000 0x1000
+			 >;
+
+		dev@0,0 {
+			compatible = "denx,u-boot-fdt-dummy";
+			reg = <0 0x0 0x1000>;
+		};
+
+		dev@1,100 {
+			compatible = "denx,u-boot-fdt-dummy";
+			reg = <1 0x100 0x1000>;
+
+		};
+
+		dev@2,200 {
+			compatible = "denx,u-boot-fdt-dummy";
+			reg = <2 0x200 0x1000>;
+		};
+
+
+		noxlatebus@3,300 {
+			compatible = "simple-bus";
+			reg = <3 0x300 0x1000>;
+
+			#address-cells = <0x1>;
+			#size-cells = <0x0>;
+
+			dev@42 {
+				compatible = "denx,u-boot-fdt-dummy";
+				reg = <0x42>;
+			};
+		};
+	};
 };
 
 #include "sandbox_pmic.dtsi"

drivers/core/fdtaddr.c

@@ -49,12 +49,17 @@ fdt_addr_t devfdt_get_addr_index(struct udevice *dev, int index)
 
 		reg += index * (na + ns);
 
-		/*
-		 * Use the full-fledged translate function for complex
-		 * bus setups.
-		 */
-		addr = fdt_translate_address((void *)gd->fdt_blob,
-					     dev_of_offset(dev), reg);
+		if (ns) {
+			/*
+			 * Use the full-fledged translate function for complex
+			 * bus setups.
+			 */
+			addr = fdt_translate_address((void *)gd->fdt_blob,
+						     dev_of_offset(dev), reg);
+		} else {
+			/* Non translatable if #size-cells == 0 */
+			addr = fdt_read_number(reg, na);
+		}
 	} else {
 		/*
 		 * Use the "simple" translate function for less complex

drivers/core/ofnode.c

@@ -227,13 +227,16 @@ fdt_addr_t ofnode_get_addr_index(ofnode node, int index)
 		uint flags;
 		u64 size;
 		int na;
+		int ns;
 
 		prop_val = of_get_address(ofnode_to_np(node), index, &size,
 					  &flags);
 		if (!prop_val)
 			return FDT_ADDR_T_NONE;
 
-		if (IS_ENABLED(CONFIG_OF_TRANSLATE)) {
+		ns = of_n_size_cells(ofnode_to_np(node));
+
+		if (IS_ENABLED(CONFIG_OF_TRANSLATE) && ns > 0) {
 			return of_translate_address(ofnode_to_np(node), prop_val);
 		} else {
 			na = of_n_addr_cells(ofnode_to_np(node));

include/dm/uclass-id.h

@@ -19,6 +19,7 @@ enum uclass_id {
 	UCLASS_TEST_FDT,
 	UCLASS_TEST_BUS,
 	UCLASS_TEST_PROBE,
+	UCLASS_TEST_DUMMY,
 	UCLASS_SPI_EMUL,	/* sandbox SPI device emulator */
 	UCLASS_I2C_EMUL,	/* sandbox I2C device emulator */
 	UCLASS_PCI_EMUL,	/* sandbox PCI device emulator */

test/dm/test-fdt.c

@@ -419,3 +419,46 @@ static int dm_test_first_next_ok_device(struct unit_test_state *uts)
 	return 0;
 }
 DM_TEST(dm_test_first_next_ok_device, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);
+
+static const struct udevice_id fdt_dummy_ids[] = {
+	{ .compatible = "denx,u-boot-fdt-dummy", },
+	{ }
+};
+
+UCLASS_DRIVER(fdt_dummy) = {
+	.name		= "fdt_dummy",
+	.id		= UCLASS_TEST_DUMMY,
+	.flags		= DM_UC_FLAG_SEQ_ALIAS,
+};
+
+U_BOOT_DRIVER(fdt_dummy_drv) = {
+	.name	= "fdt_dummy_drv",
+	.of_match	= fdt_dummy_ids,
+	.id	= UCLASS_TEST_DUMMY,
+};
+
+static int dm_test_fdt_translation(struct unit_test_state *uts)
+{
+	struct udevice *dev;
+
+	/* Some simple translations */
+	ut_assertok(uclass_find_device_by_seq(UCLASS_TEST_DUMMY, 0, true, &dev));
+	ut_asserteq_str("dev@0,0", dev->name);
+	ut_asserteq(0x8000, dev_read_addr(dev));
+
+	ut_assertok(uclass_find_device_by_seq(UCLASS_TEST_DUMMY, 1, true, &dev));
+	ut_asserteq_str("dev@1,100", dev->name);
+	ut_asserteq(0x9000, dev_read_addr(dev));
+
+	ut_assertok(uclass_find_device_by_seq(UCLASS_TEST_DUMMY, 2, true, &dev));
+	ut_asserteq_str("dev@2,200", dev->name);
+	ut_asserteq(0xA000, dev_read_addr(dev));
+
+	/* No translation for busses with #size-cells == 0 */
+	ut_assertok(uclass_find_device_by_seq(UCLASS_TEST_DUMMY, 3, true, &dev));
+	ut_asserteq_str("dev@42", dev->name);
+	ut_asserteq(0x42, dev_read_addr(dev));
+
+	return 0;
+}
+DM_TEST(dm_test_fdt_translation, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);