/* * Functions for working with the Flattened Device Tree data format * * Copyright 2009 Benjamin Herrenschmidt, IBM Corp * benh@kernel.crashing.org * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * version 2 as published by the Free Software Foundation. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* for COMMAND_LINE_SIZE */ #include /* * of_fdt_limit_memory - limit the number of regions in the /memory node * @limit: maximum entries * * Adjust the flattened device tree to have at most 'limit' number of * memory entries in the /memory node. This function may be called * any time after initial_boot_param is set. */ void of_fdt_limit_memory(int limit) { int memory; int len; const void *val; int nr_address_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT; int nr_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT; const uint32_t *addr_prop; const uint32_t *size_prop; int root_offset; int cell_size; root_offset = fdt_path_offset(initial_boot_params, "/"); if (root_offset < 0) return; addr_prop = fdt_getprop(initial_boot_params, root_offset, "#address-cells", NULL); if (addr_prop) nr_address_cells = fdt32_to_cpu(*addr_prop); size_prop = fdt_getprop(initial_boot_params, root_offset, "#size-cells", NULL); if (size_prop) nr_size_cells = fdt32_to_cpu(*size_prop); cell_size = sizeof(uint32_t)*(nr_address_cells + nr_size_cells); memory = fdt_path_offset(initial_boot_params, "/memory"); if (memory > 0) { val = fdt_getprop(initial_boot_params, memory, "reg", &len); if (len > limit*cell_size) { len = limit*cell_size; pr_debug("Limiting number of entries to %d\n", limit); fdt_setprop(initial_boot_params, memory, "reg", val, len); } } } /** * of_fdt_is_compatible - Return true if given node from the given blob has * compat in its compatible list * @blob: A device tree blob * @node: node to test * @compat: compatible string to compare with compatible list. * * On match, returns a non-zero value with smaller values returned for more * specific compatible values. */ int of_fdt_is_compatible(const void *blob, unsigned long node, const char *compat) { const char *cp; int cplen; unsigned long l, score = 0; cp = fdt_getprop(blob, node, "compatible", &cplen); if (cp == NULL) return 0; while (cplen > 0) { score++; if (of_compat_cmp(cp, compat, strlen(compat)) == 0) return score; l = strlen(cp) + 1; cp += l; cplen -= l; } return 0; } /** * of_fdt_match - Return true if node matches a list of compatible values */ int of_fdt_match(const void *blob, unsigned long node, const char *const *compat) { unsigned int tmp, score = 0; if (!compat) return 0; while (*compat) { tmp = of_fdt_is_compatible(blob, node, *compat); if (tmp && (score == 0 || (tmp < score))) score = tmp; compat++; } return score; } static void *unflatten_dt_alloc(void **mem, unsigned long size, unsigned long align) { void *res; *mem = PTR_ALIGN(*mem, align); res = *mem; *mem += size; return res; } /** * unflatten_dt_node - Alloc and populate a device_node from the flat tree * @blob: The parent device tree blob * @mem: Memory chunk to use for allocating device nodes and properties * @p: pointer to node in flat tree * @dad: Parent struct device_node * @fpsize: Size of the node path up at the current depth. */ static void * unflatten_dt_node(void *blob, void *mem, int *poffset, struct device_node *dad, struct device_node **nodepp, unsigned long fpsize, bool dryrun) { const __be32 *p; struct device_node *np; struct property *pp, **prev_pp = NULL; const char *pathp; unsigned int l, allocl; static int depth = 0; int old_depth; int offset; int has_name = 0; int new_format = 0; pathp = fdt_get_name(blob, *poffset, &l); if (!pathp) return mem; allocl = l++; /* version 0x10 has a more compact unit name here instead of the full * path. we accumulate the full path size using "fpsize", we'll rebuild * it later. We detect this because the first character of the name is * not '/'. */ if ((*pathp) != '/') { new_format = 1; if (fpsize == 0) { /* root node: special case. fpsize accounts for path * plus terminating zero. root node only has '/', so * fpsize should be 2, but we want to avoid the first * level nodes to have two '/' so we use fpsize 1 here */ fpsize = 1; allocl = 2; l = 1; pathp = ""; } else { /* account for '/' and path size minus terminal 0 * already in 'l' */ fpsize += l; allocl = fpsize; } } np = unflatten_dt_alloc(&mem, sizeof(struct device_node) + allocl, __alignof__(struct device_node)); if (!dryrun) { char *fn; of_node_init(np); np->full_name = fn = ((char *)np) + sizeof(*np); if (new_format) { /* rebuild full path for new format */ if (dad && dad->parent) { strcpy(fn, dad->full_name); #ifdef DEBUG if ((strlen(fn) + l + 1) != allocl) { pr_debug("%s: p: %d, l: %d, a: %d\n", pathp, (int)strlen(fn), l, allocl); } #endif fn += strlen(fn); } *(fn++) = '/'; } memcpy(fn, pathp, l); prev_pp = &np->properties; if (dad != NULL) { np->parent = dad; /* we temporarily use the next field as `last_child'*/ if (dad->next == NULL) dad->child = np; else dad->next->sibling = np; dad->next = np; } } /* process properties */ for (offset = fdt_first_property_offset(blob, *poffset); (offset >= 0); (offset = fdt_next_property_offset(blob, offset))) { const char *pname; u32 sz; if (!(p = fdt_getprop_by_offset(blob, offset, &pname, &sz))) { offset = -FDT_ERR_INTERNAL; break; } if (pname == NULL) { pr_info("Can't find property name in list !\n"); break; } if (strcmp(pname, "name") == 0) has_name = 1; pp = unflatten_dt_alloc(&mem, sizeof(struct property), __alignof__(struct property)); if (!dryrun) { /* We accept flattened tree phandles either in * ePAPR-style "phandle" properties, or the * legacy "linux,phandle" properties. If both * appear and have different values, things * will get weird. Don't do that. */ if ((strcmp(pname, "phandle") == 0) || (strcmp(pname, "linux,phandle") == 0)) { if (np->phandle == 0) np->phandle = be32_to_cpup(p); } /* And we process the "ibm,phandle" property * used in pSeries dynamic device tree * stuff */ if (strcmp(pname, "ibm,phandle") == 0) np->phandle = be32_to_cpup(p); pp->name = (char *)pname; pp->length = sz; pp->value = (__be32 *)p; *prev_pp = pp; prev_pp = &pp->next; } } /* with version 0x10 we may not have the name property, recreate * it here from the unit name if absent */ if (!has_name) { const char *p1 = pathp, *ps = pathp, *pa = NULL; int sz; while (*p1) { if ((*p1) == '@') pa = p1; if ((*p1) == '/') ps = p1 + 1; p1++; } if (pa < ps) pa = p1; sz = (pa - ps) + 1; pp = unflatten_dt_alloc(&mem, sizeof(struct property) + sz, __alignof__(struct property)); if (!dryrun) { pp->name = "name"; pp->length = sz; pp->value = pp + 1; *prev_pp = pp; prev_pp = &pp->next; memcpy(pp->value, ps, sz - 1); ((char *)pp->value)[sz - 1] = 0; pr_debug("fixed up name for %s -> %s\n", pathp, (char *)pp->value); } } if (!dryrun) { *prev_pp = NULL; np->name = of_get_property(np, "name", NULL); np->type = of_get_property(np, "device_type", NULL); if (!np->name) np->name = ""; if (!np->type) np->type = ""; } old_depth = depth; *poffset = fdt_next_node(blob, *poffset, &depth); if (depth < 0) depth = 0; while (*poffset > 0 && depth > old_depth) mem = unflatten_dt_node(blob, mem, poffset, np, NULL, fpsize, dryrun); if (*poffset < 0 && *poffset != -FDT_ERR_NOTFOUND) pr_err("unflatten: error %d processing FDT\n", *poffset); if (nodepp) *nodepp = np; return mem; } /** * __unflatten_device_tree - create tree of device_nodes from flat blob * * unflattens a device-tree, creating the * tree of struct device_node. It also fills the "name" and "type" * pointers of the nodes so the normal device-tree walking functions * can be used. * @blob: The blob to expand * @mynodes: The device_node tree created by the call * @dt_alloc: An allocator that provides a virtual address to memory * for the resulting tree */ static void __unflatten_device_tree(void *blob, struct device_node **mynodes, void * (*dt_alloc)(u64 size, u64 align)) { unsigned long size; int start; void *mem; pr_debug(" -> unflatten_device_tree()\n"); if (!blob) { pr_debug("No device tree pointer\n"); return; } pr_debug("Unflattening device tree:\n"); pr_debug("magic: %08x\n", fdt_magic(blob)); pr_debug("size: %08x\n", fdt_totalsize(blob)); pr_debug("version: %08x\n", fdt_version(blob)); if (fdt_check_header(blob)) { pr_err("Invalid device tree blob header\n"); return; } /* First pass, scan for size */ start = 0; size = (unsigned long)unflatten_dt_node(blob, NULL, &start, NULL, NULL, 0, true); size = ALIGN(size, 4); pr_debug(" size is %lx, allocating...\n", size); /* Allocate memory for the expanded device tree */ mem = dt_alloc(size + 4, __alignof__(struct device_node)); memset(mem, 0, size); *(__be32 *)(mem + size) = cpu_to_be32(0xdeadbeef); pr_debug(" unflattening %p...\n", mem); /* Second pass, do actual unflattening */ start = 0; unflatten_dt_node(blob, mem, &start, NULL, mynodes, 0, false); if (be32_to_cpup(mem + size) != 0xdeadbeef) pr_warning("End of tree marker overwritten: %08x\n", be32_to_cpup(mem + size)); pr_debug(" <- unflatten_device_tree()\n"); } static void *kernel_tree_alloc(u64 size, u64 align) { return kzalloc(size, GFP_KERNEL); } /** * of_fdt_unflatten_tree - create tree of device_nodes from flat blob * * unflattens the device-tree passed by the firmware, creating the * tree of struct device_node. It also fills the "name" and "type" * pointers of the nodes so the normal device-tree walking functions * can be used. */ void of_fdt_unflatten_tree(unsigned long *blob, struct device_node **mynodes) { __unflatten_device_tree(blob, mynodes, &kernel_tree_alloc); } EXPORT_SYMBOL_GPL(of_fdt_unflatten_tree); /* Everything below here references initial_boot_params directly. */ int __initdata dt_root_addr_cells; int __initdata dt_root_size_cells; void *initial_boot_params; #ifdef CONFIG_OF_EARLY_FLATTREE /** * res_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 nomap, first = 1; 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_arch(base, size, nomap) == 0) pr_debug("Reserved memory: reserved region for node '%s': base %pa, size %ld MiB\n", uname, &base, (unsigned long)size / SZ_1M); else pr_info("Reserved memory: failed to reserve memory for node '%s': base %pa, size %ld 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(unsigned long node, const char *uname, int depth, void *data) { static int found; const char *status; int err; if (!found && depth == 1 && strcmp(uname, "reserved-memory") == 0) { if (__reserved_mem_check_root(node) != 0) { pr_err("Reserved memory: unsupported node format, ignoring\n"); /* break scan */ return 1; } found = 1; /* scan next node */ return 0; } else if (!found) { /* scan next node */ return 0; } else if (found && depth < 2) { /* scanning of /reserved-memory has been finished */ return 1; } status = of_get_flat_dt_prop(node, "status", NULL); if (status && strcmp(status, "okay") != 0 && strcmp(status, "ok") != 0) return 0; err = __reserved_mem_reserve_reg(node, uname); if (err == -ENOENT && of_get_flat_dt_prop(node, "size", NULL)) fdt_reserved_mem_save_node(node, uname, 0, 0); /* scan next node */ return 0; } /** * early_init_fdt_scan_reserved_mem() - create reserved memory regions * * This function grabs memory from early allocator for device exclusive use * defined in device tree structures. It should be called by arch specific code * once the early allocator (i.e. memblock) has been fully activated. */ void __init early_init_fdt_scan_reserved_mem(void) { int n; u64 base, size; if (!initial_boot_params) return; /* Reserve the dtb region */ early_init_dt_reserve_memory_arch(__pa(initial_boot_params), fdt_totalsize(initial_boot_params), 0); /* Process header /memreserve/ fields */ for (n = 0; ; n++) { fdt_get_mem_rsv(initial_boot_params, n, &base, &size); if (!size) break; early_init_dt_reserve_memory_arch(base, size, 0); } of_scan_flat_dt(__fdt_scan_reserved_mem, NULL); fdt_init_reserved_mem(); } /** * of_scan_flat_dt - scan flattened tree blob and call callback on each. * @it: callback function * @data: context data pointer * * This function is used to scan the flattened device-tree, it is * used to extract the memory information at boot before we can * unflatten the tree */ int __init of_scan_flat_dt(int (*it)(unsigned long node, const char *uname, int depth, void *data), void *data) { const void *blob = initial_boot_params; const char *pathp; int offset, rc = 0, depth = -1; for (offset = fdt_next_node(blob, -1, &depth); offset >= 0 && depth >= 0 && !rc; offset = fdt_next_node(blob, offset, &depth)) { pathp = fdt_get_name(blob, offset, NULL); if (*pathp == '/') pathp = kbasename(pathp); rc = it(offset, pathp, depth, data); } return rc; } /** * of_get_flat_dt_root - find the root node in the flat blob */ unsigned long __init of_get_flat_dt_root(void) { return 0; } /** * of_get_flat_dt_size - Return the total size of the FDT */ int __init of_get_flat_dt_size(void) { return fdt_totalsize(initial_boot_params); } /** * of_get_flat_dt_prop - Given a node in the flat blob, return the property ptr * * This function can be used within scan_flattened_dt callback to get * access to properties */ const void *__init of_get_flat_dt_prop(unsigned long node, const char *name, int *size) { return fdt_getprop(initial_boot_params, node, name, size); } /** * of_flat_dt_is_compatible - Return true if given node has compat in compatible list * @node: node to test * @compat: compatible string to compare with compatible list. */ int __init of_flat_dt_is_compatible(unsigned long node, const char *compat) { return of_fdt_is_compatible(initial_boot_params, node, compat); } /** * of_flat_dt_match - Return true if node matches a list of compatible values */ int __init of_flat_dt_match(unsigned long node, const char *const *compat) { return of_fdt_match(initial_boot_params, node, compat); } struct fdt_scan_status { const char *name; int namelen; int depth; int found; int (*iterator)(unsigned long node, const char *uname, int depth, void *data); void *data; }; const char * __init of_flat_dt_get_machine_name(void) { const char *name; unsigned long dt_root = of_get_flat_dt_root(); name = of_get_flat_dt_prop(dt_root, "model", NULL); if (!name) name = of_get_flat_dt_prop(dt_root, "compatible", NULL); return name; } /** * of_flat_dt_match_machine - Iterate match tables to find matching machine. * * @default_match: A machine specific ptr to return in case of no match. * @get_next_compat: callback function to return next compatible match table. * * Iterate through machine match tables to find the best match for the machine * compatible string in the FDT. */ const void * __init of_flat_dt_match_machine(const void *default_match, const void * (*get_next_compat)(const char * const**)) { const void *data = NULL; const void *best_data = default_match; const char *const *compat; unsigned long dt_root; unsigned int best_score = ~1, score = 0; dt_root = of_get_flat_dt_root(); while ((data = get_next_compat(&compat))) { score = of_flat_dt_match(dt_root, compat); if (score > 0 && score < best_score) { best_data = data; best_score = score; } } if (!best_data) { const char *prop; int size; pr_err("\n unrecognized device tree list:\n[ "); prop = of_get_flat_dt_prop(dt_root, "compatible", &size); if (prop) { while (size > 0) { printk("'%s' ", prop); size -= strlen(prop) + 1; prop += strlen(prop) + 1; } } printk("]\n\n"); return NULL; } pr_info("Machine model: %s\n", of_flat_dt_get_machine_name()); return best_data; } #ifdef CONFIG_BLK_DEV_INITRD /** * early_init_dt_check_for_initrd - Decode initrd location from flat tree * @node: reference to node containing initrd location ('chosen') */ static void __init early_init_dt_check_for_initrd(unsigned long node) { u64 start, end; int len; const __be32 *prop; pr_debug("Looking for initrd properties... "); prop = of_get_flat_dt_prop(node, "linux,initrd-start", &len); if (!prop) return; start = of_read_number(prop, len/4); prop = of_get_flat_dt_prop(node, "linux,initrd-end", &len); if (!prop) return; end = of_read_number(prop, len/4); initrd_start = (unsigned long)__va(start); initrd_end = (unsigned long)__va(end); initrd_below_start_ok = 1; pr_debug("initrd_start=0x%llx initrd_end=0x%llx\n", (unsigned long long)start, (unsigned long long)end); } #else static inline void early_init_dt_check_for_initrd(unsigned long node) { } #endif /* CONFIG_BLK_DEV_INITRD */ #ifdef CONFIG_SERIAL_EARLYCON extern struct of_device_id __earlycon_of_table[]; int __init early_init_dt_scan_chosen_serial(void) { int offset; const char *p; int l; const struct of_device_id *match = __earlycon_of_table; const void *fdt = initial_boot_params; offset = fdt_path_offset(fdt, "/chosen"); if (offset < 0) offset = fdt_path_offset(fdt, "/chosen@0"); if (offset < 0) return -ENOENT; p = fdt_getprop(fdt, offset, "stdout-path", &l); if (!p) p = fdt_getprop(fdt, offset, "linux,stdout-path", &l); if (!p || !l) return -ENOENT; /* Get the node specified by stdout-path */ offset = fdt_path_offset(fdt, p); if (offset < 0) return -ENODEV; while (match->compatible) { unsigned long addr; if (fdt_node_check_compatible(fdt, offset, match->compatible)) { match++; continue; } addr = fdt_translate_address(fdt, offset); if (!addr) return -ENXIO; of_setup_earlycon(addr, match->data); return 0; } return -ENODEV; } static int __init setup_of_earlycon(char *buf) { if (buf) return 0; return early_init_dt_scan_chosen_serial(); } early_param("earlycon", setup_of_earlycon); #endif /** * early_init_dt_scan_root - fetch the top level address and size cells */ int __init early_init_dt_scan_root(unsigned long node, const char *uname, int depth, void *data) { const __be32 *prop; if (depth != 0) return 0; dt_root_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT; dt_root_addr_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT; prop = of_get_flat_dt_prop(node, "#size-cells", NULL); if (prop) dt_root_size_cells = be32_to_cpup(prop); pr_debug("dt_root_size_cells = %x\n", dt_root_size_cells); prop = of_get_flat_dt_prop(node, "#address-cells", NULL); if (prop) dt_root_addr_cells = be32_to_cpup(prop); pr_debug("dt_root_addr_cells = %x\n", dt_root_addr_cells); /* break now */ return 1; } u64 __init dt_mem_next_cell(int s, const __be32 **cellp) { const __be32 *p = *cellp; *cellp = p + s; return of_read_number(p, s); } /** * early_init_dt_scan_memory - Look for an parse memory nodes */ int __init early_init_dt_scan_memory(unsigned long node, const char *uname, int depth, void *data) { const char *type = of_get_flat_dt_prop(node, "device_type", NULL); const __be32 *reg, *endp; int l; /* We are scanning "memory" nodes only */ if (type == NULL) { /* * The longtrail doesn't have a device_type on the * /memory node, so look for the node called /memory@0. */ if (!IS_ENABLED(CONFIG_PPC32) || depth != 1 || strcmp(uname, "memory@0") != 0) return 0; } else if (strcmp(type, "memory") != 0) return 0; reg = of_get_flat_dt_prop(node, "linux,usable-memory", &l); if (reg == NULL) reg = of_get_flat_dt_prop(node, "reg", &l); if (reg == NULL) return 0; endp = reg + (l / sizeof(__be32)); pr_debug("memory scan node %s, reg size %d, data: %x %x %x %x,\n", uname, l, reg[0], reg[1], reg[2], reg[3]); while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) { u64 base, size; base = dt_mem_next_cell(dt_root_addr_cells, ®); size = dt_mem_next_cell(dt_root_size_cells, ®); if (size == 0) continue; pr_debug(" - %llx , %llx\n", (unsigned long long)base, (unsigned long long)size); early_init_dt_add_memory_arch(base, size); } return 0; } int __init early_init_dt_scan_chosen(unsigned long node, const char *uname, int depth, void *data) { int l; const char *p; pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname); if (depth != 1 || !data || (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0)) return 0; early_init_dt_check_for_initrd(node); /* Retrieve command line */ p = of_get_flat_dt_prop(node, "bootargs", &l); if (p != NULL && l > 0) strlcpy(data, p, min((int)l, COMMAND_LINE_SIZE)); /* * CONFIG_CMDLINE is meant to be a default in case nothing else * managed to set the command line, unless CONFIG_CMDLINE_FORCE * is set in which case we override whatever was found earlier. */ #ifdef CONFIG_CMDLINE #ifndef CONFIG_CMDLINE_FORCE if (!((char *)data)[0]) #endif strlcpy(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE); #endif /* CONFIG_CMDLINE */ pr_debug("Command line is: %s\n", (char*)data); /* break now */ return 1; } #ifdef CONFIG_HAVE_MEMBLOCK #define MAX_PHYS_ADDR ((phys_addr_t)~0) void __init __weak early_init_dt_add_memory_arch(u64 base, u64 size) { const u64 phys_offset = __pa(PAGE_OFFSET); if (!PAGE_ALIGNED(base)) { if (size < PAGE_SIZE - (base & ~PAGE_MASK)) { pr_warn("Ignoring memory block 0x%llx - 0x%llx\n", base, base + size); return; } size -= PAGE_SIZE - (base & ~PAGE_MASK); base = PAGE_ALIGN(base); } size &= PAGE_MASK; if (base > MAX_PHYS_ADDR) { pr_warning("Ignoring memory block 0x%llx - 0x%llx\n", base, base + size); return; } if (base + size - 1 > MAX_PHYS_ADDR) { pr_warning("Ignoring memory range 0x%llx - 0x%llx\n", ((u64)MAX_PHYS_ADDR) + 1, base + size); size = MAX_PHYS_ADDR - base + 1; } if (base + size < phys_offset) { pr_warning("Ignoring memory block 0x%llx - 0x%llx\n", base, base + size); return; } if (base < phys_offset) { pr_warning("Ignoring memory range 0x%llx - 0x%llx\n", base, phys_offset); size -= phys_offset - base; base = phys_offset; } memblock_add(base, size); } int __init __weak early_init_dt_reserve_memory_arch(phys_addr_t base, phys_addr_t size, bool nomap) { if (memblock_is_region_reserved(base, size)) return -EBUSY; if (nomap) return memblock_remove(base, size); return memblock_reserve(base, size); } /* * called from unflatten_device_tree() to bootstrap devicetree itself * Architectures can override this definition if memblock isn't used */ void * __init __weak early_init_dt_alloc_memory_arch(u64 size, u64 align) { return __va(memblock_alloc(size, align)); } #else int __init __weak early_init_dt_reserve_memory_arch(phys_addr_t base, phys_addr_t size, bool nomap) { pr_err("Reserved memory not supported, ignoring range 0x%pa - 0x%pa%s\n", &base, &size, nomap ? " (nomap)" : ""); return -ENOSYS; } #endif bool __init early_init_dt_verify(void *params) { if (!params) return false; /* check device tree validity */ if (fdt_check_header(params)) return false; /* Setup flat device-tree pointer */ initial_boot_params = params; return true; } void __init early_init_dt_scan_nodes(void) { /* Retrieve various information from the /chosen node */ of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line); /* Initialize {size,address}-cells info */ of_scan_flat_dt(early_init_dt_scan_root, NULL); /* Setup memory, calling early_init_dt_add_memory_arch */ of_scan_flat_dt(early_init_dt_scan_memory, NULL); } bool __init early_init_dt_scan(void *params) { bool status; status = early_init_dt_verify(params); if (!status) return false; early_init_dt_scan_nodes(); return true; } /** * unflatten_device_tree - create tree of device_nodes from flat blob * * unflattens the device-tree passed by the firmware, creating the * tree of struct device_node. It also fills the "name" and "type" * pointers of the nodes so the normal device-tree walking functions * can be used. */ void __init unflatten_device_tree(void) { __unflatten_device_tree(initial_boot_params, &of_root, early_init_dt_alloc_memory_arch); /* Get pointer to "/chosen" and "/aliases" nodes for use everywhere */ of_alias_scan(early_init_dt_alloc_memory_arch); } /** * unflatten_and_copy_device_tree - copy and create tree of device_nodes from flat blob * * Copies and unflattens the device-tree passed by the firmware, creating the * tree of struct device_node. It also fills the "name" and "type" * pointers of the nodes so the normal device-tree walking functions * can be used. This should only be used when the FDT memory has not been * reserved such is the case when the FDT is built-in to the kernel init * section. If the FDT memory is reserved already then unflatten_device_tree * should be used instead. */ void __init unflatten_and_copy_device_tree(void) { int size; void *dt; 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(); } #if defined(CONFIG_DEBUG_FS) && defined(DEBUG) static struct debugfs_blob_wrapper flat_dt_blob; static int __init of_flat_dt_debugfs_export_fdt(void) { struct dentry *d = debugfs_create_dir("device-tree", NULL); if (!d) return -ENOENT; flat_dt_blob.data = initial_boot_params; flat_dt_blob.size = fdt_totalsize(initial_boot_params); d = debugfs_create_blob("flat-device-tree", S_IFREG | S_IRUSR, d, &flat_dt_blob); if (!d) return -ENOENT; return 0; } module_init(of_flat_dt_debugfs_export_fdt); #endif #endif /* CONFIG_OF_EARLY_FLATTREE */