diff options
author | Rob Herring <robh@kernel.org> | 2023-03-28 23:16:00 +0300 |
---|---|---|
committer | Rob Herring <robh@kernel.org> | 2023-04-14 01:46:35 +0300 |
commit | ff61bacd77f258bd2ed145efb69e5449b115d4fe (patch) | |
tree | 66a4d268d0aa376f86b6fe023be2568a63319b72 | |
parent | b50c788a56964a900ebcc817c8a5ad35ddad87b6 (diff) | |
download | linux-ff61bacd77f258bd2ed145efb69e5449b115d4fe.tar.xz |
of/address: Add of_property_read_reg() helper
Add a helper, of_property_read_reg(), to read "reg" entries untranslated
address and size. This function is intended mainly for cases with an
untranslatable "reg" address (i.e. not MMIO). There's also a few
translatable cases such as address cells containing a bus chip-select
number.
Link: https://lore.kernel.org/r/20230328-dt-address-helpers-v1-5-e2456c3e77ab@kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
-rw-r--r-- | drivers/of/address.c | 23 | ||||
-rw-r--r-- | drivers/of/unittest.c | 22 | ||||
-rw-r--r-- | include/linux/of_address.h | 7 |
3 files changed, 52 insertions, 0 deletions
diff --git a/drivers/of/address.c b/drivers/of/address.c index 8cfae24148e0..fdb15c6fb3b1 100644 --- a/drivers/of/address.c +++ b/drivers/of/address.c @@ -760,6 +760,29 @@ const __be32 *__of_get_address(struct device_node *dev, int index, int bar_no, } EXPORT_SYMBOL(__of_get_address); +/** + * of_property_read_reg - Retrieve the specified "reg" entry index without translating + * @np: device tree node for which to retrieve "reg" from + * @idx: "reg" entry index to read + * @addr: return value for the untranslated address + * @size: return value for the entry size + * + * Returns -EINVAL if "reg" is not found. Returns 0 on success with addr and + * size values filled in. + */ +int of_property_read_reg(struct device_node *np, int idx, u64 *addr, u64 *size) +{ + const __be32 *prop = of_get_address(np, idx, size, NULL); + + if (!prop) + return -EINVAL; + + *addr = of_read_number(prop, of_n_addr_cells(np)); + + return 0; +} +EXPORT_SYMBOL(of_property_read_reg); + static int parser_init(struct of_pci_range_parser *parser, struct device_node *node, const char *name) { diff --git a/drivers/of/unittest.c b/drivers/of/unittest.c index eaeb58065acc..e73ecbef977b 100644 --- a/drivers/of/unittest.c +++ b/drivers/of/unittest.c @@ -1134,6 +1134,27 @@ static void __init of_unittest_bus_3cell_ranges(void) of_node_put(np); } +static void __init of_unittest_reg(void) +{ + struct device_node *np; + int ret; + u64 addr, size; + + np = of_find_node_by_path("/testcase-data/address-tests/bus@80000000/device@1000"); + if (!np) { + pr_err("missing testcase data\n"); + return; + } + + ret = of_property_read_reg(np, 0, &addr, &size); + unittest(!ret, "of_property_read_reg(%pOF) returned error %d\n", + np, ret); + unittest(addr == 0x1000, "of_property_read_reg(%pOF) untranslated address (%llx) incorrect\n", + np, addr); + + of_node_put(np); +} + static void __init of_unittest_parse_interrupts(void) { struct device_node *np; @@ -3772,6 +3793,7 @@ static int __init of_unittest(void) of_unittest_pci_dma_ranges(); of_unittest_bus_ranges(); of_unittest_bus_3cell_ranges(); + of_unittest_reg(); of_unittest_match_node(); of_unittest_platform_populate(); of_unittest_overlay(); diff --git a/include/linux/of_address.h b/include/linux/of_address.h index 5292f62c1baa..26a19daf0d09 100644 --- a/include/linux/of_address.h +++ b/include/linux/of_address.h @@ -72,6 +72,8 @@ void __iomem *of_io_request_and_map(struct device_node *device, extern const __be32 *__of_get_address(struct device_node *dev, int index, int bar_no, u64 *size, unsigned int *flags); +int of_property_read_reg(struct device_node *np, int idx, u64 *addr, u64 *size); + extern int of_pci_range_parser_init(struct of_pci_range_parser *parser, struct device_node *node); extern int of_pci_dma_range_parser_init(struct of_pci_range_parser *parser, @@ -106,6 +108,11 @@ static inline const __be32 *__of_get_address(struct device_node *dev, int index, return NULL; } +static inline int of_property_read_reg(struct device_node *np, int idx, u64 *addr, u64 *size) +{ + return -ENOSYS; +} + static inline int of_pci_range_parser_init(struct of_pci_range_parser *parser, struct device_node *node) { |