diff options
| author | Anup Patel <anup.patel@wdc.com> | 2021-07-13 11:23:41 +0800 |
|---|---|---|
| committer | Anup Patel <anup@brainfault.org> | 2021-07-17 11:40:49 +0530 |
| commit | e931f387b27a2f575f5b713391e241d8963b48c5 (patch) | |
| tree | 9d94f155241100b478c6defe947c69e262ee6e44 | |
| parent | 17729d44daf879e015950b0e9636afceefea0a59 (diff) | |
lib: utils/fdt: Add fdt_parse_phandle_with_args() API
The libfdt project does not have a generic API to parse phandle
with args from a DT node so we add fdt_parse_phandle_with_args()
for this purpose. This new API will be useful to FDT based drivers.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
| -rw-r--r-- | include/sbi_utils/fdt/fdt_helper.h | 11 | ||||
| -rw-r--r-- | lib/utils/fdt/fdt_helper.c | 47 |
2 files changed, 58 insertions, 0 deletions
diff --git a/include/sbi_utils/fdt/fdt_helper.h b/include/sbi_utils/fdt/fdt_helper.h index 871f9b9..55b9382 100644 --- a/include/sbi_utils/fdt/fdt_helper.h +++ b/include/sbi_utils/fdt/fdt_helper.h @@ -17,6 +17,13 @@ struct fdt_match { void *data; }; +#define FDT_MAX_PHANDLE_ARGS 16 +struct fdt_phandle_args { + int node_offset; + int args_count; + u32 args[FDT_MAX_PHANDLE_ARGS]; +}; + struct platform_uart_data { unsigned long addr; unsigned long freq; @@ -32,6 +39,10 @@ int fdt_find_match(void *fdt, int startoff, const struct fdt_match *match_table, const struct fdt_match **out_match); +int fdt_parse_phandle_with_args(void *fdt, int nodeoff, + const char *prop, const char *cells_prop, + int index, struct fdt_phandle_args *out_args); + int fdt_get_node_addr_size(void *fdt, int node, unsigned long *addr, unsigned long *size); diff --git a/lib/utils/fdt/fdt_helper.c b/lib/utils/fdt/fdt_helper.c index de77196..a970c0f 100644 --- a/lib/utils/fdt/fdt_helper.c +++ b/lib/utils/fdt/fdt_helper.c @@ -72,6 +72,53 @@ int fdt_find_match(void *fdt, int startoff, return SBI_ENODEV; } +int fdt_parse_phandle_with_args(void *fdt, int nodeoff, + const char *prop, const char *cells_prop, + int index, struct fdt_phandle_args *out_args) +{ + u32 i, pcells; + int len, pnodeoff; + const fdt32_t *list, *list_end, *val; + + if (!fdt || (nodeoff < 0) || !prop || !cells_prop || !out_args) + return SBI_EINVAL; + + list = fdt_getprop(fdt, nodeoff, prop, &len); + if (!list) + return SBI_ENOENT; + list_end = list + (len / sizeof(*list)); + + while (list < list_end) { + pnodeoff = fdt_node_offset_by_phandle(fdt, + fdt32_to_cpu(*list)); + if (pnodeoff < 0) + return pnodeoff; + list++; + + val = fdt_getprop(fdt, pnodeoff, cells_prop, &len); + if (!val) + return SBI_ENOENT; + pcells = fdt32_to_cpu(*val); + if (FDT_MAX_PHANDLE_ARGS < pcells) + return SBI_EINVAL; + if (list + pcells > list_end) + return SBI_ENOENT; + + if (index > 0) { + list += pcells; + index--; + } else { + out_args->node_offset = pnodeoff; + out_args->args_count = pcells; + for (i = 0; i < pcells; i++) + out_args->args[i] = fdt32_to_cpu(list[i]); + return 0; + } + } + + return SBI_ENOENT; +} + static int fdt_translate_address(void *fdt, uint64_t reg, int parent, unsigned long *addr) { |