diff options
Diffstat (limited to 'drivers/of/fdt.c')
| -rw-r--r-- | drivers/of/fdt.c | 187 |
1 files changed, 49 insertions, 138 deletions
diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c index bf502ba8da95..a8a04f27915b 100644 --- a/drivers/of/fdt.c +++ b/drivers/of/fdt.c @@ -8,6 +8,7 @@ #define pr_fmt(fmt) "OF: fdt: " fmt +#include <linux/acpi.h> #include <linux/crash_dump.h> #include <linux/crc32.h> #include <linux/kernel.h> @@ -16,7 +17,6 @@ #include <linux/mutex.h> #include <linux/of.h> #include <linux/of_fdt.h> -#include <linux/of_reserved_mem.h> #include <linux/sizes.h> #include <linux/string.h> #include <linux/errno.h> @@ -33,6 +33,13 @@ #include "of_private.h" /* + * __dtb_empty_root_begin[] and __dtb_empty_root_end[] magically created by + * cmd_dt_S_dtb in scripts/Makefile.lib + */ +extern uint8_t __dtb_empty_root_begin[]; +extern uint8_t __dtb_empty_root_end[]; + +/* * of_fdt_limit_memory - limit the number of regions in the /memory node * @limit: maximum entries * @@ -80,7 +87,7 @@ void __init of_fdt_limit_memory(int limit) } } -static bool of_fdt_device_is_available(const void *blob, unsigned long node) +bool of_fdt_device_is_available(const void *blob, unsigned long node) { const char *status = fdt_getprop(blob, node, "status", NULL); @@ -476,126 +483,6 @@ void *initial_boot_params __ro_after_init; static u32 of_fdt_crc32; -static int __init early_init_dt_reserve_memory(phys_addr_t base, - phys_addr_t size, bool nomap) -{ - if (nomap) { - /* - * If the memory is already reserved (by another region), we - * should not allow it to be marked nomap, but don't worry - * if the region isn't memory as it won't be mapped. - */ - if (memblock_overlaps_region(&memblock.memory, base, size) && - memblock_is_region_reserved(base, size)) - return -EBUSY; - - return memblock_mark_nomap(base, size); - } - return memblock_reserve(base, size); -} - -/* - * __reserved_mem_reserve_reg() - reserve all memory described in 'reg' property - */ -static int __init __reserved_mem_reserve_reg(unsigned long node, - const char *uname) -{ - int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32); - phys_addr_t base, size; - int len; - const __be32 *prop; - int first = 1; - bool nomap; - - prop = of_get_flat_dt_prop(node, "reg", &len); - if (!prop) - return -ENOENT; - - if (len && len % t_len != 0) { - pr_err("Reserved memory: invalid reg property in '%s', skipping node.\n", - uname); - return -EINVAL; - } - - nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL; - - while (len >= t_len) { - base = dt_mem_next_cell(dt_root_addr_cells, &prop); - size = dt_mem_next_cell(dt_root_size_cells, &prop); - - if (size && - early_init_dt_reserve_memory(base, size, nomap) == 0) - pr_debug("Reserved memory: reserved region for node '%s': base %pa, size %lu MiB\n", - uname, &base, (unsigned long)(size / SZ_1M)); - else - pr_err("Reserved memory: failed to reserve memory for node '%s': base %pa, size %lu MiB\n", - uname, &base, (unsigned long)(size / SZ_1M)); - - len -= t_len; - if (first) { - fdt_reserved_mem_save_node(node, uname, base, size); - first = 0; - } - } - return 0; -} - -/* - * __reserved_mem_check_root() - check if #size-cells, #address-cells provided - * in /reserved-memory matches the values supported by the current implementation, - * also check if ranges property has been provided - */ -static int __init __reserved_mem_check_root(unsigned long node) -{ - const __be32 *prop; - - prop = of_get_flat_dt_prop(node, "#size-cells", NULL); - if (!prop || be32_to_cpup(prop) != dt_root_size_cells) - return -EINVAL; - - prop = of_get_flat_dt_prop(node, "#address-cells", NULL); - if (!prop || be32_to_cpup(prop) != dt_root_addr_cells) - return -EINVAL; - - prop = of_get_flat_dt_prop(node, "ranges", NULL); - if (!prop) - return -EINVAL; - return 0; -} - -/* - * fdt_scan_reserved_mem() - scan a single FDT node for reserved memory - */ -static int __init fdt_scan_reserved_mem(void) -{ - int node, child; - const void *fdt = initial_boot_params; - - node = fdt_path_offset(fdt, "/reserved-memory"); - if (node < 0) - return -ENODEV; - - if (__reserved_mem_check_root(node) != 0) { - pr_err("Reserved memory: unsupported node format, ignoring\n"); - return -EINVAL; - } - - fdt_for_each_subnode(child, fdt, node) { - const char *uname; - int err; - - if (!of_fdt_device_is_available(fdt, child)) - continue; - - uname = fdt_get_name(fdt, child, NULL); - - err = __reserved_mem_reserve_reg(child, uname); - if (err == -ENOENT && of_get_flat_dt_prop(child, "size", NULL)) - fdt_reserved_mem_save_node(child, uname, 0, 0); - } - return 0; -} - /* * fdt_reserve_elfcorehdr() - reserves memory for elf core header * @@ -1318,6 +1205,21 @@ bool __init early_init_dt_scan(void *params) return true; } +static void *__init copy_device_tree(void *fdt) +{ + int size; + void *dt; + + size = fdt_totalsize(fdt); + dt = early_init_dt_alloc_memory_arch(size, + roundup_pow_of_two(FDT_V17_SIZE)); + + if (dt) + memcpy(dt, fdt, size); + + return dt; +} + /** * unflatten_device_tree - create tree of device_nodes from flat blob * @@ -1328,7 +1230,29 @@ bool __init early_init_dt_scan(void *params) */ void __init unflatten_device_tree(void) { - __unflatten_device_tree(initial_boot_params, NULL, &of_root, + void *fdt = initial_boot_params; + + /* Don't use the bootloader provided DTB if ACPI is enabled */ + if (!acpi_disabled) + fdt = NULL; + + /* + * Populate an empty root node when ACPI is enabled or bootloader + * doesn't provide one. + */ + if (!fdt) { + fdt = (void *) __dtb_empty_root_begin; + /* fdt_totalsize() will be used for copy size */ + if (fdt_totalsize(fdt) > + __dtb_empty_root_end - __dtb_empty_root_begin) { + pr_err("invalid size in dtb_empty_root\n"); + return; + } + of_fdt_crc32 = crc32_be(~0, fdt, fdt_totalsize(fdt)); + fdt = copy_device_tree(fdt); + } + + __unflatten_device_tree(fdt, NULL, &of_root, early_init_dt_alloc_memory_arch, false); /* Get pointer to "/chosen" and "/aliases" nodes for use everywhere */ @@ -1350,22 +1274,9 @@ void __init unflatten_device_tree(void) */ void __init unflatten_and_copy_device_tree(void) { - int size; - void *dt; + if (initial_boot_params) + initial_boot_params = copy_device_tree(initial_boot_params); - if (!initial_boot_params) { - pr_warn("No valid device tree found, continuing without\n"); - return; - } - - size = fdt_totalsize(initial_boot_params); - dt = early_init_dt_alloc_memory_arch(size, - roundup_pow_of_two(FDT_V17_SIZE)); - - if (dt) { - memcpy(dt, initial_boot_params, size); - initial_boot_params = dt; - } unflatten_device_tree(); } |