diff options
| -rw-r--r-- | src/include/device_tree.h | 6 | ||||
| -rw-r--r-- | src/lib/Makefile.mk | 4 | ||||
| -rw-r--r-- | src/lib/device_tree.c | 93 |
3 files changed, 102 insertions, 1 deletions
diff --git a/src/include/device_tree.h b/src/include/device_tree.h index 6d2d65600f..bb522bf1da 100644 --- a/src/include/device_tree.h +++ b/src/include/device_tree.h @@ -129,6 +129,12 @@ u32 fdt_find_node_by_alias(const void *blob, const char *alias_name, */ int fdt_next_node_name(const void *blob, uint32_t node_offset, const char **name); + /* Read memory regions from a flat device-tree. */ +size_t fdt_read_memory_regions(const void *blob, struct device_tree_region regions[], + size_t regions_count); + /* Find top of memory from a flat device-tree. */ +uint64_t fdt_get_memory_top(const void *blob); + /* Read a flattened device tree into a hierarchical structure which refers to the contents of the flattened tree in place. Modifying the flat tree invalidates the unflattened one. */ diff --git a/src/lib/Makefile.mk b/src/lib/Makefile.mk index e22fd08723..59e2116e30 100644 --- a/src/lib/Makefile.mk +++ b/src/lib/Makefile.mk @@ -160,10 +160,12 @@ ramstage-$(CONFIG_GENERIC_GPIO_LIB) += gpio.c ramstage-$(CONFIG_GENERIC_UDELAY) += timer.c ramstage-y += b64_decode.c ramstage-$(CONFIG_ACPI_NHLT) += nhlt.c -ramstage-$(CONFIG_FLATTENED_DEVICE_TREE) += device_tree.c ramstage-$(CONFIG_PAYLOAD_FIT_SUPPORT) += fit.c ramstage-$(CONFIG_PAYLOAD_FIT_SUPPORT) += fit_payload.c +romstage-$(CONFIG_FLATTENED_DEVICE_TREE) += device_tree.c +ramstage-$(CONFIG_FLATTENED_DEVICE_TREE) += device_tree.c + romstage-$(CONFIG_TIMER_QUEUE) += timer_queue.c ramstage-$(CONFIG_TIMER_QUEUE) += timer_queue.c diff --git a/src/lib/device_tree.c b/src/lib/device_tree.c index 4f5cc07e91..5087d3940d 100644 --- a/src/lib/device_tree.c +++ b/src/lib/device_tree.c @@ -12,9 +12,12 @@ #include <string.h> #include <stddef.h> #include <stdlib.h> +#include <limits.h> #define FDT_PATH_MAX_DEPTH 10 // should be a good enough upper bound #define FDT_PATH_MAX_LEN 128 // should be a good enough upper bound +#define FDT_MAX_MEMORY_NODES 4 // should be a good enough upper bound +#define FDT_MAX_MEMORY_REGIONS 16 // should be a good enough upper bound /* * Functions for picking apart flattened trees. @@ -504,6 +507,96 @@ void fdt_print_node(const void *blob, uint32_t offset) } /* + * fdt_read_memory_regions finds memory ranges from a flat device-tree + * + * @params blob address of FDT + * @params regions all regions that are read inside the reg property of + * memory nodes are saved inside this array + * @params regions_count maximum number of entries that can be saved inside + * the regions array. + * + * Returns: Either 0 on error or returns the number of regions put into the regions array. + */ +size_t fdt_read_memory_regions(const void *blob, + struct device_tree_region regions[], + size_t regions_count) +{ + u32 node, root, addrcp, sizecp; + u32 nodes[FDT_MAX_MEMORY_NODES] = {0}; + size_t region_idx = 0; + size_t node_count = 0; + + if (!fdt_is_valid(blob)) + return 0; + + node = fdt_find_node_by_path(blob, "/memory", &addrcp, &sizecp); + if (node) { + region_idx += fdt_read_reg_prop(blob, node, addrcp, sizecp, + regions, regions_count); + if (region_idx >= regions_count) { + printk(BIOS_WARNING, "FDT: Too many memory regions\n"); + goto out; + } + } + + root = fdt_find_node_by_path(blob, "/", &addrcp, &sizecp); + node_count = fdt_find_subnodes_by_prefix(blob, root, "memory@", + &addrcp, &sizecp, nodes, + FDT_MAX_MEMORY_NODES); + if (node_count >= FDT_MAX_MEMORY_NODES) { + printk(BIOS_WARNING, "FDT: Too many memory nodes\n"); + /* Can still reading the regions for those we got */ + } + + for (size_t i = 0; i < MIN(node_count, FDT_MAX_MEMORY_NODES); i++) { + region_idx += fdt_read_reg_prop(blob, nodes[i], addrcp, sizecp, + ®ions[region_idx], + regions_count - region_idx); + if (region_idx >= regions_count) { + printk(BIOS_WARNING, "FDT: Too many memory regions\n"); + goto out; + } + } + +out: + for (size_t i = 0; i < MIN(region_idx, regions_count); i++) { + printk(BIOS_DEBUG, "FDT: Memory region [%#llx - %#llx]\n", + regions[i].addr, regions[i].addr + regions[i].size); + } + + return region_idx; +} + +/* + * fdt_get_memory_top finds top of memory from a flat device-tree + * + * @params blob address of FDT + * + * Returns: Either 0 on error or returns the maximum memory address + */ +uint64_t fdt_get_memory_top(const void *blob) +{ + struct device_tree_region regions[FDT_MAX_MEMORY_REGIONS] = {0}; + uint64_t top = 0; + uint64_t total = 0; + size_t count; + + if (!fdt_is_valid(blob)) + return 0; + + count = fdt_read_memory_regions(blob, regions, FDT_MAX_MEMORY_REGIONS); + for (size_t i = 0; i < MIN(count, FDT_MAX_MEMORY_REGIONS); i++) { + top = MAX(top, regions[i].addr + regions[i].size); + total += regions[i].size; + } + + printk(BIOS_DEBUG, "FDT: Found %u MiB of RAM\n", + (uint32_t)(total / MiB)); + + return top; +} + +/* * Functions to turn a flattened tree into an unflattened one. */ |