diff options
| -rw-r--r-- | src/commonlib/device_tree.c | 97 | ||||
| -rw-r--r-- | src/commonlib/include/commonlib/device_tree.h | 2 |
2 files changed, 73 insertions, 26 deletions
diff --git a/src/commonlib/device_tree.c b/src/commonlib/device_tree.c index 0ec6ea92cd..a8a64ecbbe 100644 --- a/src/commonlib/device_tree.c +++ b/src/commonlib/device_tree.c @@ -59,10 +59,49 @@ static struct device_tree_property *alloc_prop(void) return xzalloc(sizeof(struct device_tree_property)); } + +/* + * internal functions used by both unflattened and flattened device tree variants + */ + + +static size_t read_reg_prop(struct fdt_property *prop, u32 addr_cells, u32 size_cells, + struct device_tree_region regions[], size_t regions_count) +{ + // we found the reg property, no need to parse all regions in 'reg' + size_t count = prop->size / (4 * addr_cells + 4 * size_cells); + if (count > regions_count) { + printk(BIOS_ERR, "reg property has more entries (%zd) than regions array can hold (%zd)\n", count, regions_count); + count = regions_count; + } + if (addr_cells > 2 || size_cells > 2) { + printk(BIOS_ERR, "addr_cells (%d) or size_cells (%d) bigger than 2\n", + addr_cells, size_cells); + return 0; + } + uint32_t *ptr = prop->data; + for (int i = 0; i < count; i++) { + if (addr_cells == 1) + regions[i].addr = be32dec(ptr); + else if (addr_cells == 2) + regions[i].addr = be64dec(ptr); + ptr += addr_cells; + if (size_cells == 1) + regions[i].size = be32dec(ptr); + else if (size_cells == 2) + regions[i].size = be64dec(ptr); + ptr += size_cells; + } + + return count; // return the number of regions found in the reg property +} + + /* * Functions for picking apart flattened trees. */ + static int fdt_skip_nops(const void *blob, uint32_t offset) { uint32_t *ptr = (uint32_t *)(((uint8_t *)blob) + offset); @@ -203,32 +242,7 @@ u32 fdt_read_reg_prop(const void *blob, u32 node_offset, u32 addr_cells, u32 siz return 0; } - // we found the reg property, now need to parse all regions in 'reg' - size_t count = prop.size / (4 * addr_cells + 4 * size_cells); - if (count > regions_count) { - printk(BIOS_ERR, "reg property at node_offset: %x has more entries (%zd) than regions array can hold (%zd)\n", node_offset, count, regions_count); - count = regions_count; - } - if (addr_cells > 2 || size_cells > 2) { - printk(BIOS_ERR, "addr_cells (%d) or size_cells (%d) bigger than 2\n", - addr_cells, size_cells); - return 0; - } - uint32_t *ptr = prop.data; - for (int i = 0; i < count; i++) { - if (addr_cells == 1) - regions[i].addr = be32dec(ptr); - else if (addr_cells == 2) - regions[i].addr = be64dec(ptr); - ptr += addr_cells; - if (size_cells == 1) - regions[i].size = be32dec(ptr); - else if (size_cells == 2) - regions[i].size = be64dec(ptr); - ptr += size_cells; - } - - return count; // return the number of regions found in the reg property + return read_reg_prop(&prop, addr_cells, size_cells, regions, regions_count); } static u32 fdt_read_cell_props(const void *blob, u32 node_offset, u32 *addrcp, u32 *sizecp) @@ -981,6 +995,37 @@ void dt_print_node(const struct device_tree_node *node) */ /* + * dt_read_reg_prop reads the reg property inside a node + * + * @params node device tree node to read reg property from + * @params addr_cells number of cells used for one address + * @params size_cells number of cells used for one size + * @params regions all regions that are read inside the reg property 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 dt_read_reg_prop(struct device_tree_node *node, u32 addr_cells, u32 size_cells, + struct device_tree_region regions[], size_t regions_count) +{ + struct device_tree_property *prop; + bool found = false; + list_for_each(prop, node->properties, list_node) { + if (!strcmp("reg", prop->prop.name)) { + found = true; + break; + } + } + + if (!found) { + printk(BIOS_DEBUG, "no reg property found\n"); + return 0; + } + return read_reg_prop(&prop->prop, addr_cells, size_cells, regions, regions_count); +} + +/* * Read #address-cells and #size-cells properties from a node. * * @param node The device tree node to read from. diff --git a/src/commonlib/include/commonlib/device_tree.h b/src/commonlib/include/commonlib/device_tree.h index 81377fa9df..c15d7ae5b1 100644 --- a/src/commonlib/include/commonlib/device_tree.h +++ b/src/commonlib/include/commonlib/device_tree.h @@ -147,6 +147,8 @@ uint32_t dt_flat_size(const struct device_tree *tree); /* Flatten a device tree into the buffer pointed to by dest. */ void dt_flatten(const struct device_tree *tree, void *dest); void dt_print_node(const struct device_tree_node *node); +size_t dt_read_reg_prop(struct device_tree_node *node, u32 addr_cells, u32 size_cells, + struct device_tree_region regions[], size_t regions_count); /* Read #address-cells and #size-cells properties from a node. */ void dt_read_cell_props(const struct device_tree_node *node, u32 *addrcp, u32 *sizecp); |