From 2640387148ad5e0197a8ac80c24f3473dee42a65 Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Thu, 23 Oct 2014 18:58:56 -0600 Subject: fdt: Add a function to decode a named memory region Permit decoding of a named memory region from the device tree. This allows easy run-time configuration of the address of on-chip SRAM, SDRAM, etc. Signed-off-by: Simon Glass Reviewed-by: Tom Rini --- lib/fdtdec.c | 61 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 61 insertions(+) (limited to 'lib') diff --git a/lib/fdtdec.c b/lib/fdtdec.c index 4dbd6aee85..9c332ad903 100644 --- a/lib/fdtdec.c +++ b/lib/fdtdec.c @@ -793,4 +793,65 @@ int fdtdec_pci_get_bdf(const void *fdt, int node, int *bdf) return 0; } + +int fdtdec_decode_memory_region(const void *blob, int config_node, + const char *mem_type, const char *suffix, + fdt_addr_t *basep, fdt_size_t *sizep) +{ + char prop_name[50]; + const char *mem; + fdt_size_t size, offset_size; + fdt_addr_t base, offset; + int node; + + if (config_node == -1) { + config_node = fdt_path_offset(blob, "/config"); + if (config_node < 0) { + debug("%s: Cannot find /config node\n", __func__); + return -ENOENT; + } + } + if (!suffix) + suffix = ""; + + snprintf(prop_name, sizeof(prop_name), "%s-memory%s", mem_type, + suffix); + mem = fdt_getprop(blob, config_node, prop_name, NULL); + if (!mem) { + debug("%s: No memory type for '%s', using /memory\n", __func__, + prop_name); + mem = "/memory"; + } + + node = fdt_path_offset(blob, mem); + if (node < 0) { + debug("%s: Failed to find node '%s': %s\n", __func__, mem, + fdt_strerror(node)); + return -ENOENT; + } + + /* + * Not strictly correct - the memory may have multiple banks. We just + * use the first + */ + if (fdtdec_decode_region(blob, node, "reg", &base, &size)) { + debug("%s: Failed to decode memory region %s\n", __func__, + mem); + return -EINVAL; + } + + snprintf(prop_name, sizeof(prop_name), "%s-offset%s", mem_type, + suffix); + if (fdtdec_decode_region(blob, config_node, prop_name, &offset, + &offset_size)) { + debug("%s: Failed to decode memory region '%s'\n", __func__, + prop_name); + return -EINVAL; + } + + *basep = base + offset; + *sizep = offset_size; + + return 0; +} #endif -- cgit v1.2.1