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1307 lines
32 KiB
1307 lines
32 KiB
// SPDX-License-Identifier: GPL-2.0 |
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/* |
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* Functions for working with the Flattened Device Tree data format |
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* |
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* Copyright 2009 Benjamin Herrenschmidt, IBM Corp |
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* [email protected] |
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*/ |
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|
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#define pr_fmt(fmt) "OF: fdt: " fmt |
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|
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#include <linux/crc32.h> |
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#include <linux/kernel.h> |
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#include <linux/initrd.h> |
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#include <linux/memblock.h> |
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#include <linux/mutex.h> |
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#include <linux/of.h> |
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#include <linux/of_fdt.h> |
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#include <linux/of_reserved_mem.h> |
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#include <linux/sizes.h> |
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#include <linux/string.h> |
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#include <linux/errno.h> |
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#include <linux/slab.h> |
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#include <linux/libfdt.h> |
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#include <linux/debugfs.h> |
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#include <linux/serial_core.h> |
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#include <linux/sysfs.h> |
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#include <linux/random.h> |
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#include <asm/setup.h> /* for COMMAND_LINE_SIZE */ |
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#include <asm/page.h> |
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#include "of_private.h" |
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|
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/* |
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* of_fdt_limit_memory - limit the number of regions in the /memory node |
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* @limit: maximum entries |
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* |
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* Adjust the flattened device tree to have at most 'limit' number of |
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* memory entries in the /memory node. This function may be called |
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* any time after initial_boot_param is set. |
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*/ |
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void __init of_fdt_limit_memory(int limit) |
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{ |
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int memory; |
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int len; |
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const void *val; |
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int nr_address_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT; |
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int nr_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT; |
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const __be32 *addr_prop; |
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const __be32 *size_prop; |
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int root_offset; |
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int cell_size; |
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root_offset = fdt_path_offset(initial_boot_params, "/"); |
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if (root_offset < 0) |
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return; |
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addr_prop = fdt_getprop(initial_boot_params, root_offset, |
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"#address-cells", NULL); |
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if (addr_prop) |
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nr_address_cells = fdt32_to_cpu(*addr_prop); |
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|
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size_prop = fdt_getprop(initial_boot_params, root_offset, |
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"#size-cells", NULL); |
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if (size_prop) |
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nr_size_cells = fdt32_to_cpu(*size_prop); |
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cell_size = sizeof(uint32_t)*(nr_address_cells + nr_size_cells); |
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memory = fdt_path_offset(initial_boot_params, "/memory"); |
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if (memory > 0) { |
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val = fdt_getprop(initial_boot_params, memory, "reg", &len); |
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if (len > limit*cell_size) { |
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len = limit*cell_size; |
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pr_debug("Limiting number of entries to %d\n", limit); |
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fdt_setprop(initial_boot_params, memory, "reg", val, |
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len); |
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} |
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} |
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} |
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|
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static bool of_fdt_device_is_available(const void *blob, unsigned long node) |
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{ |
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const char *status = fdt_getprop(blob, node, "status", NULL); |
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if (!status) |
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return true; |
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|
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if (!strcmp(status, "ok") || !strcmp(status, "okay")) |
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return true; |
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return false; |
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} |
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static void *unflatten_dt_alloc(void **mem, unsigned long size, |
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unsigned long align) |
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{ |
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void *res; |
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*mem = PTR_ALIGN(*mem, align); |
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res = *mem; |
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*mem += size; |
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return res; |
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} |
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static void populate_properties(const void *blob, |
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int offset, |
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void **mem, |
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struct device_node *np, |
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const char *nodename, |
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bool dryrun) |
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{ |
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struct property *pp, **pprev = NULL; |
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int cur; |
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bool has_name = false; |
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pprev = &np->properties; |
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for (cur = fdt_first_property_offset(blob, offset); |
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cur >= 0; |
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cur = fdt_next_property_offset(blob, cur)) { |
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const __be32 *val; |
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const char *pname; |
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u32 sz; |
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val = fdt_getprop_by_offset(blob, cur, &pname, &sz); |
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if (!val) { |
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pr_warn("Cannot locate property at 0x%x\n", cur); |
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continue; |
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} |
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if (!pname) { |
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pr_warn("Cannot find property name at 0x%x\n", cur); |
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continue; |
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} |
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if (!strcmp(pname, "name")) |
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has_name = true; |
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pp = unflatten_dt_alloc(mem, sizeof(struct property), |
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__alignof__(struct property)); |
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if (dryrun) |
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continue; |
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/* We accept flattened tree phandles either in |
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* ePAPR-style "phandle" properties, or the |
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* legacy "linux,phandle" properties. If both |
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* appear and have different values, things |
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* will get weird. Don't do that. |
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*/ |
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if (!strcmp(pname, "phandle") || |
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!strcmp(pname, "linux,phandle")) { |
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if (!np->phandle) |
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np->phandle = be32_to_cpup(val); |
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} |
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|
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/* And we process the "ibm,phandle" property |
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* used in pSeries dynamic device tree |
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* stuff |
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*/ |
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if (!strcmp(pname, "ibm,phandle")) |
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np->phandle = be32_to_cpup(val); |
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pp->name = (char *)pname; |
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pp->length = sz; |
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pp->value = (__be32 *)val; |
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*pprev = pp; |
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pprev = &pp->next; |
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} |
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|
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/* With version 0x10 we may not have the name property, |
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* recreate it here from the unit name if absent |
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*/ |
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if (!has_name) { |
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const char *p = nodename, *ps = p, *pa = NULL; |
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int len; |
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|
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while (*p) { |
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if ((*p) == '@') |
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pa = p; |
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else if ((*p) == '/') |
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ps = p + 1; |
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p++; |
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} |
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if (pa < ps) |
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pa = p; |
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len = (pa - ps) + 1; |
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pp = unflatten_dt_alloc(mem, sizeof(struct property) + len, |
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__alignof__(struct property)); |
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if (!dryrun) { |
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pp->name = "name"; |
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pp->length = len; |
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pp->value = pp + 1; |
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*pprev = pp; |
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pprev = &pp->next; |
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memcpy(pp->value, ps, len - 1); |
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((char *)pp->value)[len - 1] = 0; |
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pr_debug("fixed up name for %s -> %s\n", |
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nodename, (char *)pp->value); |
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} |
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} |
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if (!dryrun) |
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*pprev = NULL; |
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} |
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static int populate_node(const void *blob, |
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int offset, |
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void **mem, |
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struct device_node *dad, |
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struct device_node **pnp, |
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bool dryrun) |
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{ |
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struct device_node *np; |
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const char *pathp; |
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int len; |
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pathp = fdt_get_name(blob, offset, &len); |
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if (!pathp) { |
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*pnp = NULL; |
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return len; |
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} |
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len++; |
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np = unflatten_dt_alloc(mem, sizeof(struct device_node) + len, |
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__alignof__(struct device_node)); |
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if (!dryrun) { |
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char *fn; |
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of_node_init(np); |
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np->full_name = fn = ((char *)np) + sizeof(*np); |
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memcpy(fn, pathp, len); |
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if (dad != NULL) { |
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np->parent = dad; |
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np->sibling = dad->child; |
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dad->child = np; |
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} |
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} |
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populate_properties(blob, offset, mem, np, pathp, dryrun); |
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if (!dryrun) { |
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np->name = of_get_property(np, "name", NULL); |
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if (!np->name) |
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np->name = "<NULL>"; |
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} |
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*pnp = np; |
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return true; |
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} |
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static void reverse_nodes(struct device_node *parent) |
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{ |
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struct device_node *child, *next; |
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|
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/* In-depth first */ |
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child = parent->child; |
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while (child) { |
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reverse_nodes(child); |
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child = child->sibling; |
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} |
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/* Reverse the nodes in the child list */ |
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child = parent->child; |
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parent->child = NULL; |
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while (child) { |
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next = child->sibling; |
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child->sibling = parent->child; |
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parent->child = child; |
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child = next; |
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} |
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} |
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/** |
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* unflatten_dt_nodes - Alloc and populate a device_node from the flat tree |
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* @blob: The parent device tree blob |
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* @mem: Memory chunk to use for allocating device nodes and properties |
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* @dad: Parent struct device_node |
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* @nodepp: The device_node tree created by the call |
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* |
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* It returns the size of unflattened device tree or error code |
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*/ |
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static int unflatten_dt_nodes(const void *blob, |
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void *mem, |
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struct device_node *dad, |
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struct device_node **nodepp) |
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{ |
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struct device_node *root; |
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int offset = 0, depth = 0, initial_depth = 0; |
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#define FDT_MAX_DEPTH 64 |
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struct device_node *nps[FDT_MAX_DEPTH]; |
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void *base = mem; |
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bool dryrun = !base; |
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int ret; |
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if (nodepp) |
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*nodepp = NULL; |
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/* |
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* We're unflattening device sub-tree if @dad is valid. There are |
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* possibly multiple nodes in the first level of depth. We need |
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* set @depth to 1 to make fdt_next_node() happy as it bails |
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* immediately when negative @depth is found. Otherwise, the device |
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* nodes except the first one won't be unflattened successfully. |
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*/ |
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if (dad) |
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depth = initial_depth = 1; |
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root = dad; |
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nps[depth] = dad; |
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for (offset = 0; |
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offset >= 0 && depth >= initial_depth; |
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offset = fdt_next_node(blob, offset, &depth)) { |
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if (WARN_ON_ONCE(depth >= FDT_MAX_DEPTH)) |
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continue; |
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if (!IS_ENABLED(CONFIG_OF_KOBJ) && |
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!of_fdt_device_is_available(blob, offset)) |
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continue; |
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ret = populate_node(blob, offset, &mem, nps[depth], |
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&nps[depth+1], dryrun); |
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if (ret < 0) |
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return ret; |
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if (!dryrun && nodepp && !*nodepp) |
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*nodepp = nps[depth+1]; |
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if (!dryrun && !root) |
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root = nps[depth+1]; |
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} |
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if (offset < 0 && offset != -FDT_ERR_NOTFOUND) { |
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pr_err("Error %d processing FDT\n", offset); |
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return -EINVAL; |
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} |
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/* |
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* Reverse the child list. Some drivers assumes node order matches .dts |
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* node order |
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*/ |
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if (!dryrun) |
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reverse_nodes(root); |
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return mem - base; |
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} |
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/** |
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* __unflatten_device_tree - create tree of device_nodes from flat blob |
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* |
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* unflattens a device-tree, creating the |
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* tree of struct device_node. It also fills the "name" and "type" |
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* pointers of the nodes so the normal device-tree walking functions |
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* can be used. |
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* @blob: The blob to expand |
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* @dad: Parent device node |
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* @mynodes: The device_node tree created by the call |
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* @dt_alloc: An allocator that provides a virtual address to memory |
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* for the resulting tree |
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* @detached: if true set OF_DETACHED on @mynodes |
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* |
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* Returns NULL on failure or the memory chunk containing the unflattened |
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* device tree on success. |
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*/ |
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void *__unflatten_device_tree(const void *blob, |
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struct device_node *dad, |
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struct device_node **mynodes, |
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void *(*dt_alloc)(u64 size, u64 align), |
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bool detached) |
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{ |
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int size; |
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void *mem; |
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int ret; |
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if (mynodes) |
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*mynodes = NULL; |
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pr_debug(" -> unflatten_device_tree()\n"); |
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if (!blob) { |
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pr_debug("No device tree pointer\n"); |
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return NULL; |
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} |
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pr_debug("Unflattening device tree:\n"); |
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pr_debug("magic: %08x\n", fdt_magic(blob)); |
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pr_debug("size: %08x\n", fdt_totalsize(blob)); |
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pr_debug("version: %08x\n", fdt_version(blob)); |
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|
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if (fdt_check_header(blob)) { |
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pr_err("Invalid device tree blob header\n"); |
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return NULL; |
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} |
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|
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/* First pass, scan for size */ |
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size = unflatten_dt_nodes(blob, NULL, dad, NULL); |
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if (size <= 0) |
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return NULL; |
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size = ALIGN(size, 4); |
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pr_debug(" size is %d, allocating...\n", size); |
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|
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/* Allocate memory for the expanded device tree */ |
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mem = dt_alloc(size + 4, __alignof__(struct device_node)); |
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if (!mem) |
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return NULL; |
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memset(mem, 0, size); |
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*(__be32 *)(mem + size) = cpu_to_be32(0xdeadbeef); |
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pr_debug(" unflattening %p...\n", mem); |
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/* Second pass, do actual unflattening */ |
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ret = unflatten_dt_nodes(blob, mem, dad, mynodes); |
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if (be32_to_cpup(mem + size) != 0xdeadbeef) |
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pr_warn("End of tree marker overwritten: %08x\n", |
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be32_to_cpup(mem + size)); |
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if (ret <= 0) |
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return NULL; |
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if (detached && mynodes && *mynodes) { |
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of_node_set_flag(*mynodes, OF_DETACHED); |
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pr_debug("unflattened tree is detached\n"); |
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} |
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pr_debug(" <- unflatten_device_tree()\n"); |
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return mem; |
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} |
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static void *kernel_tree_alloc(u64 size, u64 align) |
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{ |
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return kzalloc(size, GFP_KERNEL); |
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} |
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static DEFINE_MUTEX(of_fdt_unflatten_mutex); |
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|
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/** |
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* of_fdt_unflatten_tree - create tree of device_nodes from flat blob |
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* @blob: Flat device tree blob |
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* @dad: Parent device node |
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* @mynodes: The device tree created by the call |
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* |
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* unflattens the device-tree passed by the firmware, creating the |
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* tree of struct device_node. It also fills the "name" and "type" |
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* pointers of the nodes so the normal device-tree walking functions |
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* can be used. |
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* |
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* Returns NULL on failure or the memory chunk containing the unflattened |
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* device tree on success. |
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*/ |
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void *of_fdt_unflatten_tree(const unsigned long *blob, |
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struct device_node *dad, |
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struct device_node **mynodes) |
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{ |
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void *mem; |
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mutex_lock(&of_fdt_unflatten_mutex); |
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mem = __unflatten_device_tree(blob, dad, mynodes, &kernel_tree_alloc, |
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true); |
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mutex_unlock(&of_fdt_unflatten_mutex); |
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return mem; |
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} |
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EXPORT_SYMBOL_GPL(of_fdt_unflatten_tree); |
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/* Everything below here references initial_boot_params directly. */ |
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int __initdata dt_root_addr_cells; |
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int __initdata dt_root_size_cells; |
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|
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void *initial_boot_params __ro_after_init; |
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|
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#ifdef CONFIG_OF_EARLY_FLATTREE |
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|
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static u32 of_fdt_crc32; |
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|
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/** |
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* __reserved_mem_reserve_reg() - reserve all memory described in 'reg' property |
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*/ |
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static int __init __reserved_mem_reserve_reg(unsigned long node, |
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const char *uname) |
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{ |
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int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32); |
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phys_addr_t base, size; |
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int len; |
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const __be32 *prop; |
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int first = 1; |
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bool nomap; |
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|
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prop = of_get_flat_dt_prop(node, "reg", &len); |
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if (!prop) |
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return -ENOENT; |
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|
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if (len && len % t_len != 0) { |
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pr_err("Reserved memory: invalid reg property in '%s', skipping node.\n", |
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uname); |
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return -EINVAL; |
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} |
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|
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nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL; |
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|
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while (len >= t_len) { |
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base = dt_mem_next_cell(dt_root_addr_cells, &prop); |
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size = dt_mem_next_cell(dt_root_size_cells, &prop); |
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|
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if (size && |
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early_init_dt_reserve_memory_arch(base, size, nomap) == 0) |
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pr_debug("Reserved memory: reserved region for node '%s': base %pa, size %ld MiB\n", |
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uname, &base, (unsigned long)size / SZ_1M); |
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else |
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pr_info("Reserved memory: failed to reserve memory for node '%s': base %pa, size %ld MiB\n", |
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uname, &base, (unsigned long)size / SZ_1M); |
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|
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len -= t_len; |
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if (first) { |
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fdt_reserved_mem_save_node(node, uname, base, size); |
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first = 0; |
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} |
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} |
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return 0; |
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} |
|
|
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/** |
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* __reserved_mem_check_root() - check if #size-cells, #address-cells provided |
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* in /reserved-memory matches the values supported by the current implementation, |
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* also check if ranges property has been provided |
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*/ |
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static int __init __reserved_mem_check_root(unsigned long node) |
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{ |
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const __be32 *prop; |
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|
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prop = of_get_flat_dt_prop(node, "#size-cells", NULL); |
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if (!prop || be32_to_cpup(prop) != dt_root_size_cells) |
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return -EINVAL; |
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|
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prop = of_get_flat_dt_prop(node, "#address-cells", NULL); |
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if (!prop || be32_to_cpup(prop) != dt_root_addr_cells) |
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return -EINVAL; |
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|
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prop = of_get_flat_dt_prop(node, "ranges", NULL); |
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if (!prop) |
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return -EINVAL; |
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return 0; |
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} |
|
|
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/** |
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* fdt_scan_reserved_mem() - scan a single FDT node for reserved memory |
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*/ |
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static int __init __fdt_scan_reserved_mem(unsigned long node, const char *uname, |
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int depth, void *data) |
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{ |
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static int found; |
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int err; |
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|
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if (!found && depth == 1 && strcmp(uname, "reserved-memory") == 0) { |
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if (__reserved_mem_check_root(node) != 0) { |
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pr_err("Reserved memory: unsupported node format, ignoring\n"); |
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/* break scan */ |
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return 1; |
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} |
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found = 1; |
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/* scan next node */ |
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return 0; |
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} else if (!found) { |
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/* scan next node */ |
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return 0; |
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} else if (found && depth < 2) { |
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/* scanning of /reserved-memory has been finished */ |
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return 1; |
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} |
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|
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if (!of_fdt_device_is_available(initial_boot_params, node)) |
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return 0; |
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|
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err = __reserved_mem_reserve_reg(node, uname); |
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if (err == -ENOENT && of_get_flat_dt_prop(node, "size", NULL)) |
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fdt_reserved_mem_save_node(node, uname, 0, 0); |
|
|
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/* scan next node */ |
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return 0; |
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} |
|
|
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/** |
|
* early_init_fdt_scan_reserved_mem() - create reserved memory regions |
|
* |
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* This function grabs memory from early allocator for device exclusive use |
|
* defined in device tree structures. It should be called by arch specific code |
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* once the early allocator (i.e. memblock) has been fully activated. |
|
*/ |
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void __init early_init_fdt_scan_reserved_mem(void) |
|
{ |
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int n; |
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u64 base, size; |
|
|
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if (!initial_boot_params) |
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return; |
|
|
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/* 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, false); |
|
} |
|
|
|
of_scan_flat_dt(__fdt_scan_reserved_mem, NULL); |
|
fdt_init_reserved_mem(); |
|
} |
|
|
|
/** |
|
* 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 */ |
|
early_init_dt_reserve_memory_arch(__pa(initial_boot_params), |
|
fdt_totalsize(initial_boot_params), |
|
false); |
|
} |
|
|
|
/** |
|
* 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. |
|
* @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); |
|
} |
|
|
|
/** |
|
* 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. |
|
*/ |
|
static 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_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_prop - 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); |
|
} |
|
|
|
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 |
|
static void __early_init_dt_declare_initrd(unsigned long start, |
|
unsigned long end) |
|
{ |
|
/* ARM64 would cause a BUG to occur here when CONFIG_DEBUG_VM is |
|
* enabled since __va() is called too early. ARM64 does make use |
|
* of phys_initrd_start/phys_initrd_size so we can skip this |
|
* conversion. |
|
*/ |
|
if (!IS_ENABLED(CONFIG_ARM64)) { |
|
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; |
|
|
|
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); |
|
|
|
__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", |
|
(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 |
|
|
|
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; |
|
|
|
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; |
|
|
|
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; |
|
|
|
if (of_setup_earlycon(match, offset, options) == 0) |
|
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(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 and 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; |
|
bool hotpluggable; |
|
|
|
/* We are scanning "memory" nodes only */ |
|
if (type == NULL || 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)); |
|
hotpluggable = of_get_flat_dt_prop(node, "hotpluggable", NULL); |
|
|
|
pr_debug("memory scan node %s, reg size %d,\n", uname, l); |
|
|
|
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); |
|
|
|
if (!hotpluggable) |
|
continue; |
|
|
|
if (early_init_dt_mark_hotplug_memory_arch(base, size)) |
|
pr_warn("failed to mark hotplug range 0x%llx - 0x%llx\n", |
|
base, 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; |
|
const void *rng_seed; |
|
|
|
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(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 |
|
#if defined(CONFIG_CMDLINE_EXTEND) |
|
strlcat(data, " ", COMMAND_LINE_SIZE); |
|
strlcat(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE); |
|
#elif defined(CONFIG_CMDLINE_FORCE) |
|
strlcpy(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE); |
|
#else |
|
/* No arguments from boot loader, use kernel's cmdl*/ |
|
if (!((char *)data)[0]) |
|
strlcpy(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE); |
|
#endif |
|
#endif /* CONFIG_CMDLINE */ |
|
|
|
pr_debug("Command line is: %s\n", (char *)data); |
|
|
|
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)); |
|
} |
|
|
|
/* break now */ |
|
return 1; |
|
} |
|
|
|
#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); |
|
} |
|
|
|
int __init __weak early_init_dt_mark_hotplug_memory_arch(u64 base, u64 size) |
|
{ |
|
return memblock_mark_hotplug(base, size); |
|
} |
|
|
|
int __init __weak early_init_dt_reserve_memory_arch(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. |
|
*/ |
|
if (memblock_is_region_reserved(base, size)) |
|
return -EBUSY; |
|
|
|
return memblock_mark_nomap(base, size); |
|
} |
|
return memblock_reserve(base, size); |
|
} |
|
|
|
static void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align) |
|
{ |
|
void *ptr = memblock_alloc(size, align); |
|
|
|
if (!ptr) |
|
panic("%s: Failed to allocate %llu bytes align=0x%llx\n", |
|
__func__, size, align); |
|
|
|
return ptr; |
|
} |
|
|
|
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; |
|
of_fdt_crc32 = crc32_be(~0, initial_boot_params, |
|
fdt_totalsize(initial_boot_params)); |
|
return true; |
|
} |
|
|
|
|
|
void __init early_init_dt_scan_nodes(void) |
|
{ |
|
int rc = 0; |
|
|
|
/* Retrieve various information from the /chosen node */ |
|
rc = of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line); |
|
if (!rc) |
|
pr_warn("No chosen node found, continuing without\n"); |
|
|
|
/* 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, 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) |
|
{ |
|
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(); |
|
} |
|
|
|
#ifdef CONFIG_SYSFS |
|
static ssize_t of_fdt_raw_read(struct file *filp, struct kobject *kobj, |
|
struct bin_attribute *bin_attr, |
|
char *buf, loff_t off, size_t count) |
|
{ |
|
memcpy(buf, initial_boot_params + off, count); |
|
return count; |
|
} |
|
|
|
static int __init of_fdt_raw_init(void) |
|
{ |
|
static struct bin_attribute of_fdt_raw_attr = |
|
__BIN_ATTR(fdt, S_IRUSR, of_fdt_raw_read, NULL, 0); |
|
|
|
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; |
|
} |
|
of_fdt_raw_attr.size = fdt_totalsize(initial_boot_params); |
|
return sysfs_create_bin_file(firmware_kobj, &of_fdt_raw_attr); |
|
} |
|
late_initcall(of_fdt_raw_init); |
|
#endif |
|
|
|
#endif /* CONFIG_OF_EARLY_FLATTREE */
|
|
|