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(I'm so sorry!) Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux
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#define pr_fmt(fmt) "OF: fdt: " fmt
#include <linux/crash_dump.h>#include <linux/crc32.h>#include <linux/kernel.h>#include <linux/initrd.h>#include <linux/memblock.h>#include <linux/mutex.h>#include <linux/of.h>#include <linux/of_fdt.h>#include <linux/sizes.h>#include <linux/string.h>#include <linux/errno.h>#include <linux/slab.h>#include <linux/libfdt.h>#include <linux/debugfs.h>#include <linux/serial_core.h>#include <linux/sysfs.h>#include <linux/random.h>#include <linux/kexec_handover.h>
#include <asm/setup.h> /* for COMMAND_LINE_SIZE */#include <asm/page.h>
#include "of_private.h"
/* * __dtb_empty_root_begin[] and __dtb_empty_root_end[] magically created by * cmd_wrap_S_dtb in scripts/Makefile.dtbs */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 * * 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 __init of_fdt_limit_memory(int limit){ int memory; int len; const void *val; int cell_size = sizeof(uint32_t)*(dt_root_addr_cells + dt_root_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); } }}
bool of_fdt_device_is_available(const void *blob, unsigned long node){ const char *status = fdt_stringlist_get(blob, node, "status", 0, NULL);
if (!status) return true;
if (!strcmp(status, "ok") || !strcmp(status, "okay")) return true;
return false;}
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;}
static void populate_properties(const void *blob, int offset, void **mem, struct device_node *np, const char *nodename, bool dryrun){ struct property *pp, **pprev = NULL; int cur; bool has_name = false;
pprev = &np->properties; for (cur = fdt_first_property_offset(blob, offset); cur >= 0; cur = fdt_next_property_offset(blob, cur)) { const __be32 *val; const char *pname; u32 sz;
val = fdt_getprop_by_offset(blob, cur, &pname, &sz); if (!val) { pr_warn("Cannot locate property at 0x%x\n", cur); continue; }
if (!pname) { pr_warn("Cannot find property name at 0x%x\n", cur); continue; }
if (!strcmp(pname, "name")) has_name = true;
pp = unflatten_dt_alloc(mem, sizeof(struct property), __alignof__(struct property)); if (dryrun) continue;
/* 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") || !strcmp(pname, "linux,phandle")) { if (!np->phandle) np->phandle = be32_to_cpup(val); }
/* And we process the "ibm,phandle" property * used in pSeries dynamic device tree * stuff */ if (IS_ENABLED(CONFIG_PPC_PSERIES) && !strcmp(pname, "ibm,phandle")) np->phandle = be32_to_cpup(val);
pp->name = (char *)pname; pp->length = sz; pp->value = (__be32 *)val; *pprev = pp; pprev = &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 *p = nodename, *ps = p, *pa = NULL; int len;
while (*p) { if ((*p) == '@') pa = p; else if ((*p) == '/') ps = p + 1; p++; }
if (pa < ps) pa = p; len = (pa - ps) + 1; pp = unflatten_dt_alloc(mem, sizeof(struct property) + len, __alignof__(struct property)); if (!dryrun) { pp->name = "name"; pp->length = len; pp->value = pp + 1; *pprev = pp; memcpy(pp->value, ps, len - 1); ((char *)pp->value)[len - 1] = 0; pr_debug("fixed up name for %s -> %s\n", nodename, (char *)pp->value); } }}
static int populate_node(const void *blob, int offset, void **mem, struct device_node *dad, struct device_node **pnp, bool dryrun){ struct device_node *np; const char *pathp; int len;
pathp = fdt_get_name(blob, offset, &len); if (!pathp) { *pnp = NULL; return len; }
len++;
np = unflatten_dt_alloc(mem, sizeof(struct device_node) + len, __alignof__(struct device_node)); if (!dryrun) { char *fn; of_node_init(np); np->full_name = fn = ((char *)np) + sizeof(*np);
memcpy(fn, pathp, len);
if (dad != NULL) { np->parent = dad; np->sibling = dad->child; dad->child = np; } }
populate_properties(blob, offset, mem, np, pathp, dryrun); if (!dryrun) { np->name = of_get_property(np, "name", NULL); if (!np->name) np->name = "<NULL>"; }
*pnp = np; return 0;}
static void reverse_nodes(struct device_node *parent){ struct device_node *child, *next;
/* In-depth first */ child = parent->child; while (child) { reverse_nodes(child);
child = child->sibling; }
/* Reverse the nodes in the child list */ child = parent->child; parent->child = NULL; while (child) { next = child->sibling;
child->sibling = parent->child; parent->child = child; child = next; }}
/** * unflatten_dt_nodes - 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 * @dad: Parent struct device_node * @nodepp: The device_node tree created by the call * * Return: The size of unflattened device tree or error code */static int unflatten_dt_nodes(const void *blob, void *mem, struct device_node *dad, struct device_node **nodepp){ struct device_node *root; int offset = 0, depth = 0, initial_depth = 0;#define FDT_MAX_DEPTH 64 struct device_node *nps[FDT_MAX_DEPTH]; void *base = mem; bool dryrun = !base; int ret;
if (nodepp) *nodepp = NULL;
/* * We're unflattening device sub-tree if @dad is valid. There are * possibly multiple nodes in the first level of depth. We need * set @depth to 1 to make fdt_next_node() happy as it bails * immediately when negative @depth is found. Otherwise, the device * nodes except the first one won't be unflattened successfully. */ if (dad) depth = initial_depth = 1;
root = dad; nps[depth] = dad;
for (offset = 0; offset >= 0 && depth >= initial_depth; offset = fdt_next_node(blob, offset, &depth)) { if (WARN_ON_ONCE(depth >= FDT_MAX_DEPTH - 1)) continue;
if (!IS_ENABLED(CONFIG_OF_KOBJ) && !of_fdt_device_is_available(blob, offset)) continue;
ret = populate_node(blob, offset, &mem, nps[depth], &nps[depth+1], dryrun); if (ret < 0) return ret;
if (!dryrun && nodepp && !*nodepp) *nodepp = nps[depth+1]; if (!dryrun && !root) root = nps[depth+1]; }
if (offset < 0 && offset != -FDT_ERR_NOTFOUND) { pr_err("Error %d processing FDT\n", offset); return -EINVAL; }
/* * Reverse the child list. Some drivers assumes node order matches .dts * node order */ if (!dryrun) reverse_nodes(root);
return mem - base;}
/** * __unflatten_device_tree - create tree of device_nodes from flat blob * @blob: The blob to expand * @dad: Parent device node * @mynodes: The device_node tree created by the call * @dt_alloc: An allocator that provides a virtual address to memory * for the resulting tree * @detached: if true set OF_DETACHED on @mynodes * * 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. * * Return: NULL on failure or the memory chunk containing the unflattened * device tree on success. */void *__unflatten_device_tree(const void *blob, struct device_node *dad, struct device_node **mynodes, void *(*dt_alloc)(u64 size, u64 align), bool detached){ int size; void *mem; int ret;
if (mynodes) *mynodes = NULL;
pr_debug(" -> unflatten_device_tree()\n");
if (!blob) { pr_debug("No device tree pointer\n"); return NULL; }
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 NULL; }
/* First pass, scan for size */ size = unflatten_dt_nodes(blob, NULL, dad, NULL); if (size <= 0) return NULL;
size = ALIGN(size, 4); pr_debug(" size is %d, allocating...\n", size);
/* Allocate memory for the expanded device tree */ mem = dt_alloc(size + 4, __alignof__(struct device_node)); if (!mem) return NULL;
*(__be32 *)(mem + size) = cpu_to_be32(0xdeadbeef);
pr_debug(" unflattening %p...\n", mem);
/* Second pass, do actual unflattening */ ret = unflatten_dt_nodes(blob, mem, dad, mynodes);
if (be32_to_cpup(mem + size) != 0xdeadbeef) pr_warn("End of tree marker overwritten: %08x\n", be32_to_cpup(mem + size));
if (ret <= 0) return NULL;
if (detached && mynodes && *mynodes) { of_node_set_flag(*mynodes, OF_DETACHED); pr_debug("unflattened tree is detached\n"); }
pr_debug(" <- unflatten_device_tree()\n"); return mem;}
static void *kernel_tree_alloc(u64 size, u64 align){ return kzalloc(size, GFP_KERNEL);}
static DEFINE_MUTEX(of_fdt_unflatten_mutex);
/** * of_fdt_unflatten_tree - create tree of device_nodes from flat blob * @blob: Flat device tree blob * @dad: Parent device node * @mynodes: The device tree created by the call * * 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. * * Return: NULL on failure or the memory chunk containing the unflattened * device tree on success. */void *of_fdt_unflatten_tree(const unsigned long *blob, struct device_node *dad, struct device_node **mynodes){ void *mem;
mutex_lock(&of_fdt_unflatten_mutex); mem = __unflatten_device_tree(blob, dad, mynodes, &kernel_tree_alloc, true); mutex_unlock(&of_fdt_unflatten_mutex);
return mem;}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 __ro_after_init;phys_addr_t initial_boot_params_pa __ro_after_init;
#ifdef CONFIG_OF_EARLY_FLATTREE
static u32 of_fdt_crc32;
/* * fdt_reserve_elfcorehdr() - reserves memory for elf core header * * This function reserves the memory occupied by an elf core header * described in the device tree. This region contains all the * information about primary kernel's core image and is used by a dump * capture kernel to access the system memory on primary kernel. */static void __init fdt_reserve_elfcorehdr(void){ if (!IS_ENABLED(CONFIG_CRASH_DUMP) || !elfcorehdr_size) return;
if (memblock_is_region_reserved(elfcorehdr_addr, elfcorehdr_size)) { pr_warn("elfcorehdr is overlapped\n"); return; }
memblock_reserve(elfcorehdr_addr, elfcorehdr_size);
pr_info("Reserving %llu KiB of memory at 0x%llx for elfcorehdr\n", elfcorehdr_size >> 10, elfcorehdr_addr);}
/** * 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; int res; u64 base, size;
if (!initial_boot_params) return;
fdt_reserve_elfcorehdr(); fdt_scan_reserved_mem();
/* Process header /memreserve/ fields */ for (n = 0; ; n++) { res = fdt_get_mem_rsv(initial_boot_params, n, &base, &size); if (res) { pr_err("Invalid memory reservation block index %d\n", n); break; } if (!size) break; memblock_reserve(base, size); }}
/** * early_init_fdt_reserve_self() - reserve the memory used by the FDT blob */void __init early_init_fdt_reserve_self(void){ if (!initial_boot_params) return;
/* Reserve the dtb region */ memblock_reserve(__pa(initial_boot_params), fdt_totalsize(initial_boot_params));}
/** * 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;
if (!blob) return 0;
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); rc = it(offset, pathp, depth, data); } return rc;}
/** * of_scan_flat_dt_subnodes - scan sub-nodes of a node call callback on each. * @parent: parent node * @it: callback function * @data: context data pointer * * This function is used to scan sub-nodes of a node. */int __init of_scan_flat_dt_subnodes(unsigned long parent, int (*it)(unsigned long node, const char *uname, void *data), void *data){ const void *blob = initial_boot_params; int node;
fdt_for_each_subnode(node, blob, parent) { const char *pathp; int rc;
pathp = fdt_get_name(blob, node, NULL); rc = it(node, pathp, data); if (rc) return rc; } return 0;}
/** * of_get_flat_dt_subnode_by_name - get the subnode by given name * * @node: the parent node * @uname: the name of subnode * @return offset of the subnode, or -FDT_ERR_NOTFOUND if there is none */
int __init of_get_flat_dt_subnode_by_name(unsigned long node, const char *uname){ return fdt_subnode_offset(initial_boot_params, node, uname);}
/* * 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_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);}
const __be32 *__init of_flat_dt_get_addr_size_prop(unsigned long node, const char *name, int *entries){ const __be32 *prop; int len, elen = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
prop = of_get_flat_dt_prop(node, name, &len); if (!prop || len % elen) { *entries = 0; return NULL; }
*entries = len / elen; return prop;}
bool __init of_flat_dt_get_addr_size(unsigned long node, const char *name, u64 *addr, u64 *size){ const __be32 *prop; int entries;
prop = of_flat_dt_get_addr_size_prop(node, name, &entries); if (!prop || entries != 1) return false;
of_flat_dt_read_addr_size(prop, 0, addr, size); return true;}
void __init of_flat_dt_read_addr_size(const __be32 *prop, int entry_index, u64 *addr, u64 *size){ int entry_cells = dt_root_addr_cells + dt_root_size_cells; prop += entry_cells * entry_index;
*addr = dt_mem_next_cell(dt_root_addr_cells, &prop); *size = dt_mem_next_cell(dt_root_size_cells, &prop);}
/** * 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. * * Return: a non-zero value on match with smaller values returned for more * specific compatible values. */static int of_fdt_is_compatible(const void *blob, unsigned long node, const char *compat){ const char *cp; int idx = 0, score = 0;
while ((cp = fdt_stringlist_get(blob, node, "compatible", idx++, NULL))) { score++; if (of_compat_cmp(cp, compat, strlen(compat)) == 0) return score; }
return 0;}
/** * 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 */static int __init of_flat_dt_match(unsigned long node, const char *const *compat){ unsigned int tmp, score = 0;
if (!compat) return 0;
while (*compat) { tmp = of_fdt_is_compatible(initial_boot_params, node, *compat); if (tmp && (score == 0 || (tmp < score))) score = tmp; compat++; }
return score;}
/* * of_get_flat_dt_phandle - Given a node in the flat blob, return the phandle */uint32_t __init of_get_flat_dt_phandle(unsigned long node){ return fdt_get_phandle(initial_boot_params, node);}
const char * __init of_flat_dt_get_machine_name(void){ const char *name; unsigned long dt_root = of_get_flat_dt_root();
name = fdt_stringlist_get(initial_boot_params, dt_root, "model", 0, NULL); if (!name) name = fdt_stringlist_get(initial_boot_params, dt_root, "compatible", 0, 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 idx = 0, size;
pr_err("\n unrecognized device tree list:\n[ ");
while ((prop = fdt_stringlist_get(initial_boot_params, dt_root, "compatible", idx++, &size))) pr_err("'%s' ", prop); pr_err("]\n\n"); return NULL; }
pr_info("Machine model: %s\n", of_flat_dt_get_machine_name());
return best_data;}
static void __early_init_dt_declare_initrd(unsigned long start, unsigned long end){ /* * __va() is not yet available this early on some platforms. In that * case, the platform uses phys_initrd_start/phys_initrd_size instead * and does the VA conversion itself. */ if (!IS_ENABLED(CONFIG_ARM64) && !(IS_ENABLED(CONFIG_RISCV) && IS_ENABLED(CONFIG_64BIT))) { initrd_start = (unsigned long)__va(start); initrd_end = (unsigned long)__va(end); initrd_below_start_ok = 1; }}
/** * 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;
if (!IS_ENABLED(CONFIG_BLK_DEV_INITRD)) return;
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); if (start > end) return;
__early_init_dt_declare_initrd(start, end); phys_initrd_start = start; phys_initrd_size = end - start;
pr_debug("initrd_start=0x%llx initrd_end=0x%llx\n", start, end);}
/** * early_init_dt_check_for_elfcorehdr - Decode elfcorehdr location from flat * tree * @node: reference to node containing elfcorehdr location ('chosen') */static void __init early_init_dt_check_for_elfcorehdr(unsigned long node){ if (!IS_ENABLED(CONFIG_CRASH_DUMP)) return;
pr_debug("Looking for elfcorehdr property... ");
if (!of_flat_dt_get_addr_size(node, "linux,elfcorehdr", &elfcorehdr_addr, &elfcorehdr_size)) return;
pr_debug("elfcorehdr_start=0x%llx elfcorehdr_size=0x%llx\n", elfcorehdr_addr, elfcorehdr_size);}
static void __init early_init_dt_check_for_dmcryptkeys(unsigned long node){ const char *prop_name = "linux,dmcryptkeys"; const __be32 *prop;
if (!IS_ENABLED(CONFIG_CRASH_DM_CRYPT)) return;
pr_debug("Looking for dmcryptkeys property... ");
prop = of_get_flat_dt_prop(node, prop_name, NULL); if (!prop) return;
dm_crypt_keys_addr = dt_mem_next_cell(dt_root_addr_cells, &prop);
/* Property only accessible to crash dump kernel */ fdt_delprop(initial_boot_params, node, prop_name);}
static unsigned long chosen_node_offset = -FDT_ERR_NOTFOUND;
/* * The main usage of linux,usable-memory-range is for crash dump kernel. * Originally, the number of usable-memory regions is one. Now there may * be 2 + CRASHK_CMA_RANGES_MAX regions, low region, high region and cma * regions. To make compatibility with existing user-space and older kdump, * the high and low region are always the first two ranges of * linux,usable-memory-range if exist. */#define MAX_USABLE_RANGES (2 + CRASHK_CMA_RANGES_MAX)
/** * early_init_dt_check_for_usable_mem_range - Decode usable memory range * location from flat tree */void __init early_init_dt_check_for_usable_mem_range(void){ struct memblock_region rgn[MAX_USABLE_RANGES] = {0}; const __be32 *prop; int len, i; u64 base, size; unsigned long node = chosen_node_offset;
if ((long)node < 0) return;
pr_debug("Looking for usable-memory-range property... ");
prop = of_flat_dt_get_addr_size_prop(node, "linux,usable-memory-range", &len); if (!prop) return;
len = min(len, MAX_USABLE_RANGES);
for (i = 0; i < len; i++) { of_flat_dt_read_addr_size(prop, i, &base, &size); rgn[i].base = base; rgn[i].size = size;
pr_debug("cap_mem_regions[%d]: base=%pa, size=%pa\n", i, &rgn[i].base, &rgn[i].size); }
memblock_cap_memory_range(rgn[0].base, rgn[0].size); for (i = 1; i < MAX_USABLE_RANGES && rgn[i].size; i++) memblock_add(rgn[i].base, rgn[i].size);}
/** * early_init_dt_check_kho - Decode info required for kexec handover from DT */static void __init early_init_dt_check_kho(void){ unsigned long node = chosen_node_offset; u64 fdt_start, fdt_size, bootmem_start, bootmem_size;
if (!IS_ENABLED(CONFIG_KEXEC_HANDOVER) || (long)node < 0) return;
if (!of_flat_dt_get_addr_size(node, "linux,kho-fdt", &fdt_start, &fdt_size)) return;
if (!of_flat_dt_get_addr_size(node, "linux,kho-bootmem", &bootmem_start, &bootmem_size)) return;
kho_populate(fdt_start, fdt_size, bootmem_start, bootmem_size);}
#ifdef CONFIG_SERIAL_EARLYCON
int __init early_init_dt_scan_chosen_stdout(void){ int offset; const char *p, *q, *options = NULL; int l; const struct earlycon_id *match; const void *fdt = initial_boot_params; int ret;
offset = fdt_path_offset(fdt, "/chosen"); if (offset < 0) offset = fdt_path_offset(fdt, "/chosen@0"); if (offset < 0) return -ENOENT;
p = fdt_stringlist_get(fdt, offset, "stdout-path", 0, &l); if (!p) p = fdt_stringlist_get(fdt, offset, "linux,stdout-path", 0, &l); if (!p || !l) return -ENOENT;
q = strchrnul(p, ':'); if (*q != '\0') options = q + 1; l = q - p;
/* Get the node specified by stdout-path */ offset = fdt_path_offset_namelen(fdt, p, l); if (offset < 0) { pr_warn("earlycon: stdout-path %.*s not found\n", l, p); return 0; }
for (match = __earlycon_table; match < __earlycon_table_end; match++) { if (!match->compatible[0]) continue;
if (fdt_node_check_compatible(fdt, offset, match->compatible)) continue;
ret = of_setup_earlycon(match, offset, options); if (!ret || ret == -EALREADY) return 0; } return -ENODEV;}#endif
/* * early_init_dt_scan_root - fetch the top level address and size cells */int __init early_init_dt_scan_root(void){ const __be32 *prop; const void *fdt = initial_boot_params; int node = fdt_path_offset(fdt, "/");
if (node < 0) return -ENODEV;
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 (!WARN(!prop, "No '#size-cells' in root node\n")) 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 (!WARN(!prop, "No '#address-cells' in root node\n")) dt_root_addr_cells = be32_to_cpup(prop); pr_debug("dt_root_addr_cells = %x\n", dt_root_addr_cells);
return 0;}
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 and parse memory nodes */int __init early_init_dt_scan_memory(void){ int node, found_memory = 0; const void *fdt = initial_boot_params;
fdt_for_each_subnode(node, fdt, 0) { const char *type = fdt_stringlist_get(fdt, node, "device_type", 0, NULL); const __be32 *reg; int i, l; bool hotpluggable;
/* We are scanning "memory" nodes only */ if (type == NULL || strcmp(type, "memory") != 0) continue;
if (!of_fdt_device_is_available(fdt, node)) continue;
reg = of_flat_dt_get_addr_size_prop(node, "linux,usable-memory", &l); if (reg == NULL) reg = of_flat_dt_get_addr_size_prop(node, "reg", &l); if (reg == NULL) continue;
hotpluggable = of_get_flat_dt_prop(node, "hotpluggable", NULL);
pr_debug("memory scan node %s, reg {addr,size} entries %d,\n", fdt_get_name(fdt, node, NULL), l);
for (i = 0; i < l; i++) { u64 base, size;
of_flat_dt_read_addr_size(reg, i, &base, &size);
if (size == 0) continue; pr_debug(" - %llx, %llx\n", base, size);
early_init_dt_add_memory_arch(base, size);
found_memory = 1;
if (!hotpluggable) continue;
if (memblock_mark_hotplug(base, size)) pr_warn("failed to mark hotplug range 0x%llx - 0x%llx\n", base, base + size); } } return found_memory;}
int __init early_init_dt_scan_chosen(char *cmdline){ int l, node; const char *p; const void *rng_seed; const void *fdt = initial_boot_params;
node = fdt_path_offset(fdt, "/chosen"); if (node < 0) node = fdt_path_offset(fdt, "/chosen@0"); if (node < 0) /* Handle the cmdline config options even if no /chosen node */ goto handle_cmdline;
chosen_node_offset = node;
early_init_dt_check_for_initrd(node); early_init_dt_check_for_elfcorehdr(node); early_init_dt_check_for_dmcryptkeys(node);
rng_seed = of_get_flat_dt_prop(node, "rng-seed", &l); if (rng_seed && l > 0) { add_bootloader_randomness(rng_seed, l);
/* try to clear seed so it won't be found. */ fdt_nop_property(initial_boot_params, node, "rng-seed");
/* update CRC check value */ of_fdt_crc32 = crc32_be(~0, initial_boot_params, fdt_totalsize(initial_boot_params)); }
/* Retrieve command line */ p = of_get_flat_dt_prop(node, "bootargs", &l); if (p != NULL && l > 0) strscpy(cmdline, p, min(l, COMMAND_LINE_SIZE));
handle_cmdline: /* * 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#if defined(CONFIG_CMDLINE_EXTEND) strlcat(cmdline, " ", COMMAND_LINE_SIZE); strlcat(cmdline, CONFIG_CMDLINE, COMMAND_LINE_SIZE);#elif defined(CONFIG_CMDLINE_FORCE) strscpy(cmdline, CONFIG_CMDLINE, COMMAND_LINE_SIZE);#else /* No arguments from boot loader, use kernel's cmdl*/ if (!((char *)cmdline)[0]) strscpy(cmdline, CONFIG_CMDLINE, COMMAND_LINE_SIZE);#endif#endif /* CONFIG_CMDLINE */
pr_debug("Command line is: %s\n", (char *)cmdline);
return 0;}
#ifndef MIN_MEMBLOCK_ADDR#define MIN_MEMBLOCK_ADDR __pa(PAGE_OFFSET)#endif#ifndef MAX_MEMBLOCK_ADDR#define MAX_MEMBLOCK_ADDR ((phys_addr_t)~0)#endif
void __init __weak early_init_dt_add_memory_arch(u64 base, u64 size){ const u64 phys_offset = MIN_MEMBLOCK_ADDR;
if (size < PAGE_SIZE - (base & ~PAGE_MASK)) { pr_warn("Ignoring memory block 0x%llx - 0x%llx\n", base, base + size); return; }
if (!PAGE_ALIGNED(base)) { size -= PAGE_SIZE - (base & ~PAGE_MASK); base = PAGE_ALIGN(base); } size &= PAGE_MASK;
if (base > MAX_MEMBLOCK_ADDR) { pr_warn("Ignoring memory block 0x%llx - 0x%llx\n", base, base + size); return; }
if (base + size - 1 > MAX_MEMBLOCK_ADDR) { pr_warn("Ignoring memory range 0x%llx - 0x%llx\n", ((u64)MAX_MEMBLOCK_ADDR) + 1, base + size); size = MAX_MEMBLOCK_ADDR - base + 1; }
if (base + size < phys_offset) { pr_warn("Ignoring memory block 0x%llx - 0x%llx\n", base, base + size); return; } if (base < phys_offset) { pr_warn("Ignoring memory range 0x%llx - 0x%llx\n", base, phys_offset); size -= phys_offset - base; base = phys_offset; } memblock_add(base, size);}
static void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align){ return memblock_alloc_or_panic(size, align);}
bool __init early_init_dt_verify(void *dt_virt, phys_addr_t dt_phys){ if (!dt_virt) return false;
/* check device tree validity */ if (fdt_check_header(dt_virt)) return false;
/* Setup flat device-tree pointer */ initial_boot_params = dt_virt; initial_boot_params_pa = dt_phys; of_fdt_crc32 = crc32_be(~0, initial_boot_params, fdt_totalsize(initial_boot_params));
/* Initialize {size,address}-cells info */ early_init_dt_scan_root();
return true;}
void __init early_init_dt_scan_nodes(void){ int rc;
/* Retrieve various information from the /chosen node */ rc = early_init_dt_scan_chosen(boot_command_line); if (rc) pr_warn("No chosen node found, continuing without\n");
/* Setup memory, calling early_init_dt_add_memory_arch */ early_init_dt_scan_memory();
/* Handle linux,usable-memory-range property */ early_init_dt_check_for_usable_mem_range();
/* Handle kexec handover */ early_init_dt_check_kho();}
bool __init early_init_dt_scan(void *dt_virt, phys_addr_t dt_phys){ bool status;
status = early_init_dt_verify(dt_virt, dt_phys); if (!status) return false;
early_init_dt_scan_nodes(); 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 * * 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){ void *fdt = initial_boot_params;
/* Save the statically-placed regions in the reserved_mem array */ fdt_scan_reserved_mem_late();
/* Populate an empty root node when 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 */ of_alias_scan(early_init_dt_alloc_memory_arch);
unittest_unflatten_overlay_base();}
/** * 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){ if (initial_boot_params) initial_boot_params = copy_device_tree(initial_boot_params);
unflatten_device_tree();}
#ifdef CONFIG_SYSFSstatic int __init of_fdt_raw_init(void){ static __ro_after_init BIN_ATTR_SIMPLE_ADMIN_RO(fdt);
if (!initial_boot_params) return 0;
if (of_fdt_crc32 != crc32_be(~0, initial_boot_params, fdt_totalsize(initial_boot_params))) { pr_warn("not creating '/sys/firmware/fdt': CRC check failed\n"); return 0; } bin_attr_fdt.private = initial_boot_params; bin_attr_fdt.size = fdt_totalsize(initial_boot_params); return sysfs_create_bin_file(firmware_kobj, &bin_attr_fdt);}late_initcall(of_fdt_raw_init);#endif
#endif /* CONFIG_OF_EARLY_FLATTREE */