[PATCH v2 15/30] fdt: translate address if #size-cells = <0>
Dario Binacchi
dariobin at libero.it
Sun Sep 6 14:11:45 CEST 2020
The __of_translate_address routine translates an address from the
device tree into a CPU physical address. A note in the description of
the routine explains that the crossing of any level with
#size-cells = <0> is to be considered an error not by specification but
since inherited from IBM. This does not happen for Texas Instruments, or
at least for the beaglebone device tree. Without this patch, in fact,
the translation into physical addresses of the registers contained in the
am33xx-clocks.dtsi nodes would not be possible. They all have a parent
with #size-cells = <0>.
The CONFIG_OF_TRANSLATE_ZERO_SIZE_CELLS symbol makes translation
possible even in the case of crossing levels with #size-cells = <0>.
The patch acts conservatively on address translation, except for
removing a check within the of_translate_one function in the
drivers/core/of_addr.c file:
+
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);
debug("empty ranges; 1:1 translation\n");
There are two reasons:
1 The function of_empty_ranges_quirk always returns false, invalidating
the following if statement in case of null ranges. Therefore one of
the two checks is useless.
2 The implementation of the of_translate_one function found in the
common/fdt_support.c file has removed this check while keeping the one
about the 1:1 translation.
The patch adds a test and modifies a check for the correctness of an
address in the case of enabling translation also for zero size cells.
The added test checks translations of addresses generated by nodes of
a device tree similar to those you can find in the files am33xx.dtsi
and am33xx-clocks.dtsi for which the patch was created.
The patch was also tested on a beaglebone black board. The addresses
generated for the registers of the loaded drivers are those specified
by the AM335x reference manual.
Signed-off-by: Dario Binacchi <dariobin at libero.it>
Tested-by: Dario Binacchi <dariobin at libero.it>
---
Changes in v2:
- Fix a missing line in the commit message.
- Add dm_flags to global_data structure and GD_DM_FLG_SIZE_CELLS_0 macro
to test without recompiling.
- Update the OF_CHECK_COUNTS macro in order to have just one
#define by bringing the GD_DM_FLG_SIZE_CELLS_0 into the expression.
- Lower-case the 0xC019 hex number.
arch/sandbox/dts/test.dts | 21 ++++++++++
common/fdt_support.c | 6 ++-
drivers/core/Kconfig | 12 ++++++
drivers/core/fdtaddr.c | 2 +-
drivers/core/of_addr.c | 14 ++-----
drivers/core/ofnode.c | 7 +++-
drivers/core/root.c | 3 ++
include/asm-generic/global_data.h | 6 +++
test/dm/test-fdt.c | 68 ++++++++++++++++++++++++++++++-
9 files changed, 123 insertions(+), 16 deletions(-)
diff --git a/arch/sandbox/dts/test.dts b/arch/sandbox/dts/test.dts
index 9f45c48e4e..af701d2086 100644
--- a/arch/sandbox/dts/test.dts
+++ b/arch/sandbox/dts/test.dts
@@ -39,6 +39,7 @@
fdt-dummy1 = "/translation-test at 8000/dev at 1,100";
fdt-dummy2 = "/translation-test at 8000/dev at 2,200";
fdt-dummy3 = "/translation-test at 8000/noxlatebus at 3,300/dev at 42";
+ fdt-dummy4 = "/translation-test at 8000/xlatebus at 4,400/devs/dev at 19";
usb0 = &usb_0;
usb1 = &usb_1;
usb2 = &usb_2;
@@ -978,6 +979,7 @@
1 0x100 0x9000 0x1000
2 0x200 0xA000 0x1000
3 0x300 0xB000 0x1000
+ 4 0x400 0xC000 0x1000
>;
dma-ranges = <0 0x000 0x10000000 0x1000
@@ -1014,6 +1016,25 @@
reg = <0x42>;
};
};
+
+ xlatebus at 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 at 19 {
+ compatible = "denx,u-boot-fdt-dummy";
+ reg = <0x19>;
+ };
+ };
+ };
+
};
osd {
diff --git a/common/fdt_support.c b/common/fdt_support.c
index a565b470f8..d8cf6f5725 100644
--- a/common/fdt_support.c
+++ b/common/fdt_support.c
@@ -20,6 +20,8 @@
#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 +1003,8 @@ 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)
+#define OF_CHECK_COUNTS(na, ns) (((na) > 0 && (na) <= OF_MAX_ADDR_CELLS) && \
+ ((ns) > 0 || (gd->dm_flags & GD_DM_FLG_SIZE_CELLS_0)))
/* Debug utility */
#ifdef DEBUG
diff --git a/drivers/core/Kconfig b/drivers/core/Kconfig
index 00d1d80dc3..2a683ae404 100644
--- a/drivers/core/Kconfig
+++ b/drivers/core/Kconfig
@@ -217,6 +217,18 @@ 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 8b48aa5bc5..51a0093d65 100644
--- a/drivers/core/fdtaddr.c
+++ b/drivers/core/fdtaddr.c
@@ -49,7 +49,7 @@ fdt_addr_t devfdt_get_addr_index(const struct udevice *dev, int index)
reg += index * (na + ns);
- if (ns) {
+ if (ns || (gd->dm_flags & GD_DM_FLG_SIZE_CELLS_0)) {
/*
* 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 ca34d84922..a590533c8a 100644
--- a/drivers/core/of_addr.c
+++ b/drivers/core/of_addr.c
@@ -18,7 +18,9 @@
/* 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)
+#define OF_CHECK_COUNTS(na, ns) (OF_CHECK_ADDR_COUNT(na) && \
+ ((ns) > 0 || \
+ (gd->dm_flags & GD_DM_FLG_SIZE_CELLS_0)))
static struct of_bus *of_match_bus(struct device_node *np);
@@ -162,11 +164,6 @@ 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,
@@ -193,11 +190,8 @@ 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 d02d8d33fe..ab97332f1d 100644
--- a/drivers/core/ofnode.c
+++ b/drivers/core/ofnode.c
@@ -304,7 +304,8 @@ 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) {
+ if (IS_ENABLED(CONFIG_OF_TRANSLATE) &&
+ (ns > 0 || (gd->dm_flags & GD_DM_FLG_SIZE_CELLS_0))) {
return of_translate_address(ofnode_to_np(node), prop_val);
} else {
na = of_n_addr_cells(ofnode_to_np(node));
@@ -655,8 +656,10 @@ 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)
+ if (CONFIG_IS_ENABLED(OF_TRANSLATE) &&
+ (ns > 0 || (gd->dm_flags & GD_DM_FLG_SIZE_CELLS_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 0726be6b79..193164238a 100644
--- a/drivers/core/root.c
+++ b/drivers/core/root.c
@@ -135,6 +135,9 @@ 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 d4a4e2215d..d0014e812c 100644
--- a/include/asm-generic/global_data.h
+++ b/include/asm-generic/global_data.h
@@ -64,6 +64,7 @@ typedef struct global_data {
struct global_data *new_gd; /* relocated global data */
#ifdef CONFIG_DM
+ unsigned long dm_flags;
struct udevice *dm_root; /* Root instance for Driver Model */
struct udevice *dm_root_f; /* Pre-relocation root instance */
struct list_head uclass_root; /* Head of core tree */
@@ -169,4 +170,9 @@ typedef struct global_data {
#define GD_FLG_SKIP_LL_INIT 0x20000 /* Don't perform low-level init */
#define GD_FLG_SMP_READY 0x40000 /* SMP init is complete */
+/*
+ * Global Data Driver Model Flags
+ */
+#define GD_DM_FLG_SIZE_CELLS_0 0x00001 /* Enable #size-cells=<0> translation */
+
#endif /* __ASM_GENERIC_GBL_DATA_H */
diff --git a/test/dm/test-fdt.c b/test/dm/test-fdt.c
index 04802deb7f..632f388d02 100644
--- a/test/dm/test-fdt.c
+++ b/test/dm/test-fdt.c
@@ -581,6 +581,64 @@ 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;
@@ -599,11 +657,19 @@ static int dm_test_fdt_translation(struct unit_test_state *uts)
ut_asserteq_str("dev at 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 at 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, true, &dev));
+ ut_asserteq_str("dev at 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, true, &dev));
dma_addr[0] = cpu_to_be32(0);
--
2.17.1
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