Revert "fdt: translate address if #size-cells = <0>"

This reverts commit d64b9cdcd475eb7f07b49741ded87e24dae4a5fc.

As pointed by [1] and [2], the reverted patch made every DT 'reg'
property translatable. What the patch was trying to fix was fixed in a
different way from previously submitted patches which instead of
correcting the generic address translation function fixed the issue with
appropriate platform code.

[1] https://patchwork.ozlabs.org/project/uboot/patch/1614324949-61314-1-git-send-email-bmeng.cn@gmail.com/
[2] https://lore.kernel.org/linux-clk/20210402192054.7934-1-dariobin@libero.it/T/

Signed-off-by: Dario Binacchi <dariobin@libero.it>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

9 files changed, 15 insertions, 141 deletions

diff --git a/arch/sandbox/dts/test.dts b/arch/sandbox/dts/test.dts
index fe26ced31d..5ca3bc502a 100644
--- a/arch/sandbox/dts/test.dts
+++ b/arch/sandbox/dts/test.dts
@@ -45,7 +45,6 @@
 		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";
-		fdt-dummy4 = "/translation-test@8000/xlatebus@4,400/devs/dev@19";
 		usb0 = &usb_0;
 		usb1 = &usb_1;
 		usb2 = &usb_2;
@@ -1270,7 +1269,6 @@
 			  1 0x100 0x9000 0x1000
 			  2 0x200 0xA000 0x1000
 			  3 0x300 0xB000 0x1000
-			  4 0x400 0xC000 0x1000
 			 >;
 
 		dma-ranges = <0 0x000 0x10000000 0x1000
@@ -1307,25 +1305,6 @@
 				reg = <0x42>;
 			};
 		};
-
-		xlatebus@4,400 {
-			compatible = "sandbox,zero-size-cells-bus";
-			reg = <4 0x400 0x1000>;
-			#address-cells = <1>;
-			#size-cells = <1>;
-			ranges = <0 4 0x400 0x1000>;
-
-			devs {
-				#address-cells = <1>;
-				#size-cells = <0>;
-
-				dev@19 {
-					compatible = "denx,u-boot-fdt-dummy";
-					reg = <0x19>;
-				};
-			};
-		};
-
 	};
 
 	osd {
diff --git a/common/fdt_support.c b/common/fdt_support.c
index 7eb5ba3bb2..695d8e134a 100644
--- a/common/fdt_support.c
+++ b/common/fdt_support.c
@@ -20,8 +20,6 @@
 #include <exports.h>
 #include <fdtdec.h>
 
-DECLARE_GLOBAL_DATA_PTR;
-
 /**
  * fdt_getprop_u32_default_node - Return a node's property or a default
  *
@@ -1001,8 +999,8 @@ void fdt_del_node_and_alias(void *blob, const char *alias)
 /* Max address size we deal with */
 #define OF_MAX_ADDR_CELLS	4
 #define OF_BAD_ADDR	FDT_ADDR_T_NONE
-#define OF_CHECK_COUNTS(na, ns) (((na) > 0 && (na) <= OF_MAX_ADDR_CELLS) && \
-			 ((ns) > 0 || gd_size_cells_0()))
+#define OF_CHECK_COUNTS(na, ns)	((na) > 0 && (na) <= OF_MAX_ADDR_CELLS && \
+			(ns) > 0)
 
 /* Debug utility */
 #ifdef DEBUG
diff --git a/drivers/core/Kconfig b/drivers/core/Kconfig
index a7c3120860..d618e1637b 100644
--- a/drivers/core/Kconfig
+++ b/drivers/core/Kconfig
@@ -271,18 +271,6 @@ config OF_TRANSLATE
 	  used for the address translation. This function is faster and
 	  smaller in size than fdt_translate_address().
 
-config OF_TRANSLATE_ZERO_SIZE_CELLS
-	bool "Enable translation for zero size cells"
-	depends on OF_TRANSLATE
-	default n
-	help
-	  The routine used to translate an FDT address into a physical CPU
-	  address was developed by IBM. It considers that crossing any level
-	  with #size-cells = <0> makes translation impossible, even if it is
-	  not the way it was specified.
-	  Enabling this option makes translation possible even in the case
-	  of crossing levels with #size-cells = <0>.
-
 config SPL_OF_TRANSLATE
 	bool "Translate addresses using fdt_translate_address in SPL"
 	depends on SPL_DM && SPL_OF_CONTROL
diff --git a/drivers/core/fdtaddr.c b/drivers/core/fdtaddr.c
index 83a50b6a3a..b9874c743d 100644
--- a/drivers/core/fdtaddr.c
+++ b/drivers/core/fdtaddr.c
@@ -50,7 +50,7 @@ fdt_addr_t devfdt_get_addr_index(const struct udevice *dev, int index)
 
 		reg += index * (na + ns);
 
-		if (ns || gd_size_cells_0()) {
+		if (ns) {
 			/*
 			 * Use the full-fledged translate function for complex
 			 * bus setups.
diff --git a/drivers/core/of_addr.c b/drivers/core/of_addr.c
index b3e384d2ee..9b77308182 100644
--- a/drivers/core/of_addr.c
+++ b/drivers/core/of_addr.c
@@ -18,8 +18,7 @@
 /* Max address size we deal with */
 #define OF_MAX_ADDR_CELLS	4
 #define OF_CHECK_ADDR_COUNT(na)	((na) > 0 && (na) <= OF_MAX_ADDR_CELLS)
-#define OF_CHECK_COUNTS(na, ns)	(OF_CHECK_ADDR_COUNT(na) && \
-				 ((ns) > 0 || gd_size_cells_0()))
+#define OF_CHECK_COUNTS(na, ns)	(OF_CHECK_ADDR_COUNT(na) && (ns) > 0)
 
 static struct of_bus *of_match_bus(struct device_node *np);
 
@@ -163,6 +162,11 @@ const __be32 *of_get_address(const struct device_node *dev, int index,
 }
 EXPORT_SYMBOL(of_get_address);
 
+static int of_empty_ranges_quirk(const struct device_node *np)
+{
+	return false;
+}
+
 static int of_translate_one(const struct device_node *parent,
 			    struct of_bus *bus, struct of_bus *pbus,
 			    __be32 *addr, int na, int ns, int pna,
@@ -189,8 +193,11 @@ static int of_translate_one(const struct device_node *parent,
 	 * As far as we know, this damage only exists on Apple machines, so
 	 * This code is only enabled on powerpc. --gcl
 	 */
-
 	ranges = of_get_property(parent, rprop, &rlen);
+	if (ranges == NULL && !of_empty_ranges_quirk(parent)) {
+		debug("no ranges; cannot translate\n");
+		return 1;
+	}
 	if (ranges == NULL || rlen == 0) {
 		offset = of_read_number(addr, na);
 		memset(addr, 0, pna * 4);
diff --git a/drivers/core/ofnode.c b/drivers/core/ofnode.c
index d50533338e..6c771e364f 100644
--- a/drivers/core/ofnode.c
+++ b/drivers/core/ofnode.c
@@ -319,8 +319,7 @@ fdt_addr_t ofnode_get_addr_size_index(ofnode node, int index, fdt_size_t *size)
 
 		ns = of_n_size_cells(ofnode_to_np(node));
 
-		if (IS_ENABLED(CONFIG_OF_TRANSLATE) &&
-		    (ns > 0 || gd_size_cells_0())) {
+		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));
@@ -703,10 +702,8 @@ fdt_addr_t ofnode_get_addr_size(ofnode node, const char *property,
 		ns = of_n_size_cells(np);
 		*sizep = of_read_number(prop + na, ns);
 
-		if (CONFIG_IS_ENABLED(OF_TRANSLATE) &&
-		    (ns > 0 || gd_size_cells_0())) {
+		if (CONFIG_IS_ENABLED(OF_TRANSLATE) && ns > 0)
 			return of_translate_address(np, prop);
-		}
 		else
 			return of_read_number(prop, na);
 	} else {
diff --git a/drivers/core/root.c b/drivers/core/root.c
index f852d867db..fe0562cd6f 100644
--- a/drivers/core/root.c
+++ b/drivers/core/root.c
@@ -164,9 +164,6 @@ int dm_init(bool of_live)
 {
 	int ret;
 
-	if (IS_ENABLED(CONFIG_OF_TRANSLATE_ZERO_SIZE_CELLS))
-		gd->dm_flags |= GD_DM_FLG_SIZE_CELLS_0;
-
 	if (gd->dm_root) {
 		dm_warn("Virtual root driver already exists!\n");
 		return -EINVAL;
diff --git a/include/asm-generic/global_data.h b/include/asm-generic/global_data.h
index e1a5f4b1d1..47921d27b1 100644
--- a/include/asm-generic/global_data.h
+++ b/include/asm-generic/global_data.h
@@ -184,12 +184,6 @@ struct global_data {
 
 #ifdef CONFIG_DM
 	/**
-	 * @dm_flags: additional flags for Driver Model
-	 *
-	 * See &enum gd_dm_flags
-	 */
-	unsigned long dm_flags;
-	/**
 	 * @dm_root: root instance for Driver Model
 	 */
 	struct udevice *dm_root;
@@ -519,12 +513,6 @@ struct global_data {
 #define gd_acpi_ctx()		NULL
 #endif
 
-#if CONFIG_IS_ENABLED(DM)
-#define gd_size_cells_0()	(gd->dm_flags & GD_DM_FLG_SIZE_CELLS_0)
-#else
-#define gd_size_cells_0()	(0)
-#endif
-
 /**
  * enum gd_flags - global data flags
  *
@@ -609,18 +597,6 @@ enum gd_flags {
 	GD_FLG_SMP_READY = 0x40000,
 };
 
-/**
- * enum gd_dm_flags - global data flags for Driver Model
- *
- * See field dm_flags of &struct global_data.
- */
-enum gd_dm_flags {
-	/**
-	 * @GD_DM_FLG_SIZE_CELLS_0: Enable #size-cells=<0> translation
-	 */
-	GD_DM_FLG_SIZE_CELLS_0 = 0x00001,
-};
-
 #endif /* __ASSEMBLY__ */
 
 #endif /* __ASM_GENERIC_GBL_DATA_H */
diff --git a/test/dm/test-fdt.c b/test/dm/test-fdt.c
index 6552d09ba3..9b771fdf19 100644
--- a/test/dm/test-fdt.c
+++ b/test/dm/test-fdt.c
@@ -5,7 +5,6 @@
 
 #include <common.h>
 #include <dm.h>
-#include <dm/device_compat.h>
 #include <errno.h>
 #include <fdtdec.h>
 #include <log.h>
@@ -551,64 +550,6 @@ U_BOOT_DRIVER(fdt_dummy_drv) = {
 	.id	= UCLASS_TEST_DUMMY,
 };
 
-static int zero_size_cells_bus_bind(struct udevice *dev)
-{
-	ofnode child;
-	int err;
-
-	ofnode_for_each_subnode(child, dev_ofnode(dev)) {
-		if (ofnode_get_property(child, "compatible", NULL))
-			continue;
-
-		err = device_bind_driver_to_node(dev,
-						 "zero_size_cells_bus_child_drv",
-						 "zero_size_cells_bus_child",
-						 child, NULL);
-		if (err) {
-			dev_err(dev, "%s: failed to bind %s\n", __func__,
-				ofnode_get_name(child));
-			return err;
-		}
-	}
-
-	return 0;
-}
-
-static const struct udevice_id zero_size_cells_bus_ids[] = {
-	{ .compatible = "sandbox,zero-size-cells-bus" },
-	{ }
-};
-
-U_BOOT_DRIVER(zero_size_cells_bus) = {
-	.name = "zero_size_cells_bus_drv",
-	.id = UCLASS_TEST_DUMMY,
-	.of_match = zero_size_cells_bus_ids,
-	.bind = zero_size_cells_bus_bind,
-};
-
-static int zero_size_cells_bus_child_bind(struct udevice *dev)
-{
-	ofnode child;
-	int err;
-
-	ofnode_for_each_subnode(child, dev_ofnode(dev)) {
-		err = lists_bind_fdt(dev, child, NULL, false);
-		if (err) {
-			dev_err(dev, "%s: lists_bind_fdt, err=%d\n",
-				__func__, err);
-			return err;
-		}
-	}
-
-	return 0;
-}
-
-U_BOOT_DRIVER(zero_size_cells_bus_child_drv) = {
-	.name = "zero_size_cells_bus_child_drv",
-	.id = UCLASS_TEST_DUMMY,
-	.bind = zero_size_cells_bus_child_bind,
-};
-
 static int dm_test_fdt_translation(struct unit_test_state *uts)
 {
 	struct udevice *dev;
@@ -630,17 +571,8 @@ static int dm_test_fdt_translation(struct unit_test_state *uts)
 	/* No translation for busses with #size-cells == 0 */
 	ut_assertok(uclass_find_device_by_seq(UCLASS_TEST_DUMMY, 3, &dev));
 	ut_asserteq_str("dev@42", dev->name);
-	/* No translation for busses with #size-cells == 0 */
 	ut_asserteq(0x42, dev_read_addr(dev));
 
-	/* Translation for busses with #size-cells == 0 */
-	gd->dm_flags |= GD_DM_FLG_SIZE_CELLS_0;
-	ut_asserteq(0x8042, dev_read_addr(dev));
-	ut_assertok(uclass_find_device_by_seq(UCLASS_TEST_DUMMY, 4, &dev));
-	ut_asserteq_str("dev@19", dev->name);
-	ut_asserteq(0xc019, dev_read_addr(dev));
-	gd->dm_flags &= ~GD_DM_FLG_SIZE_CELLS_0;
-
 	/* dma address translation */
 	ut_assertok(uclass_find_device_by_seq(UCLASS_TEST_DUMMY, 0, &dev));
 	dma_addr[0] = cpu_to_be32(0);