linux/drivers/of/fdt.c
Linus Torvalds 607ca0f742 TTY / Serial driver changes for 6.0-rc1
Here is the big set of tty and serial driver changes for 6.0-rc1.
 
 It was delayed from last week as I wanted to make sure the last commit
 here got some good testing in linux-next and elsewhere as it seemed to
 show up only late in testing for some reason.
 
 Nothing major here, just lots of cleanups from Jiri and Ilpo to make the
 tty core cleaner (Jiri) and the rs485 code simpler to use (Ilpo).  Also
 included in here is the obligatory n_gsm updates from Daniel Starke and
 lots of tiny driver updates and minor fixes and tweaks for other smaller
 serial drivers.
 
 Full details are in the shortlog.
 
 All of these have been in linux-next for a while with no reported
 problems.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-6.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty / serial driver updates from Greg KH:
 "Here is the big set of tty and serial driver changes for 6.0-rc1.

  It was delayed from last week as I wanted to make sure the last commit
  here got some good testing in linux-next and elsewhere as it seemed to
  show up only late in testing for some reason.

  Nothing major here, just lots of cleanups from Jiri and Ilpo to make
  the tty core cleaner (Jiri) and the rs485 code simpler to use (Ilpo).

  Also included in here is the obligatory n_gsm updates from Daniel
  Starke and lots of tiny driver updates and minor fixes and tweaks for
  other smaller serial drivers.

  All of these have been in linux-next for a while with no reported
  problems"

* tag 'tty-6.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (186 commits)
  tty: serial: qcom-geni-serial: Fix %lu -> %u in print statements
  tty: amiserial: Fix comment typo
  tty: serial: document uart_get_console()
  tty: serial: serial_core, reformat kernel-doc for functions
  Documentation: serial: link uart_ops properly
  Documentation: serial: move GPIO kernel-doc to the functions
  Documentation: serial: dedup kernel-doc for uart functions
  Documentation: serial: move uart_ops documentation to the struct
  dt-bindings: serial: snps-dw-apb-uart: Document Rockchip RV1126
  serial: mvebu-uart: uart2 error bits clearing
  tty: serial: fsl_lpuart: correct the count of break characters
  serial: stm32: make info structs static to avoid sparse warnings
  serial: fsl_lpuart: zero out parity bit in CS7 mode
  tty: serial: qcom-geni-serial: Fix get_clk_div_rate() which otherwise could return a sub-optimal clock rate.
  serial: 8250_bcm2835aux: Add missing clk_disable_unprepare()
  tty: vt: initialize unicode screen buffer
  serial: remove VR41XX serial driver
  serial: 8250: lpc18xx: Remove redundant sanity check for RS485 flags
  serial: 8250_dwlib: remove redundant sanity check for RS485 flags
  dt_bindings: rs485: Correct delay values
  ...
2022-08-08 11:31:40 -07:00

1406 lines
34 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Functions for working with the Flattened Device Tree data format
*
* Copyright 2009 Benjamin Herrenschmidt, IBM Corp
* benh@kernel.crashing.org
*/
#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/of_reserved_mem.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/kmemleak.h>
#include <asm/setup.h> /* for COMMAND_LINE_SIZE */
#include <asm/page.h>
#include "of_private.h"
/*
* 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 nr_address_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
int nr_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
const __be32 *addr_prop;
const __be32 *size_prop;
int root_offset;
int cell_size;
root_offset = fdt_path_offset(initial_boot_params, "/");
if (root_offset < 0)
return;
addr_prop = fdt_getprop(initial_boot_params, root_offset,
"#address-cells", NULL);
if (addr_prop)
nr_address_cells = fdt32_to_cpu(*addr_prop);
size_prop = fdt_getprop(initial_boot_params, root_offset,
"#size-cells", NULL);
if (size_prop)
nr_size_cells = fdt32_to_cpu(*size_prop);
cell_size = sizeof(uint32_t)*(nr_address_cells + nr_size_cells);
memory = fdt_path_offset(initial_boot_params, "/memory");
if (memory > 0) {
val = fdt_getprop(initial_boot_params, memory, "reg", &len);
if (len > limit*cell_size) {
len = limit*cell_size;
pr_debug("Limiting number of entries to %d\n", limit);
fdt_setprop(initial_boot_params, memory, "reg", val,
len);
}
}
}
static bool of_fdt_device_is_available(const void *blob, unsigned long node)
{
const char *status = fdt_getprop(blob, node, "status", 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 (!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))
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;
memset(mem, 0, size);
*(__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;
#ifdef CONFIG_OF_EARLY_FLATTREE
static u32 of_fdt_crc32;
static int __init early_init_dt_reserve_memory(phys_addr_t base,
phys_addr_t size, bool nomap)
{
if (nomap) {
/*
* If the memory is already reserved (by another region), we
* should not allow it to be marked nomap, but don't worry
* if the region isn't memory as it won't be mapped.
*/
if (memblock_overlaps_region(&memblock.memory, base, size) &&
memblock_is_region_reserved(base, size))
return -EBUSY;
return memblock_mark_nomap(base, size);
}
return memblock_reserve(base, size);
}
/*
* __reserved_mem_reserve_reg() - reserve all memory described in 'reg' property
*/
static int __init __reserved_mem_reserve_reg(unsigned long node,
const char *uname)
{
int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
phys_addr_t base, size;
int len;
const __be32 *prop;
int first = 1;
bool nomap;
prop = of_get_flat_dt_prop(node, "reg", &len);
if (!prop)
return -ENOENT;
if (len && len % t_len != 0) {
pr_err("Reserved memory: invalid reg property in '%s', skipping node.\n",
uname);
return -EINVAL;
}
nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
while (len >= t_len) {
base = dt_mem_next_cell(dt_root_addr_cells, &prop);
size = dt_mem_next_cell(dt_root_size_cells, &prop);
if (size &&
early_init_dt_reserve_memory(base, size, nomap) == 0) {
pr_debug("Reserved memory: reserved region for node '%s': base %pa, size %lu MiB\n",
uname, &base, (unsigned long)(size / SZ_1M));
if (!nomap)
kmemleak_alloc_phys(base, size, 0);
}
else
pr_err("Reserved memory: failed to reserve memory for node '%s': base %pa, size %lu MiB\n",
uname, &base, (unsigned long)(size / SZ_1M));
len -= t_len;
if (first) {
fdt_reserved_mem_save_node(node, uname, base, size);
first = 0;
}
}
return 0;
}
/*
* __reserved_mem_check_root() - check if #size-cells, #address-cells provided
* in /reserved-memory matches the values supported by the current implementation,
* also check if ranges property has been provided
*/
static int __init __reserved_mem_check_root(unsigned long node)
{
const __be32 *prop;
prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
if (!prop || be32_to_cpup(prop) != dt_root_size_cells)
return -EINVAL;
prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
if (!prop || be32_to_cpup(prop) != dt_root_addr_cells)
return -EINVAL;
prop = of_get_flat_dt_prop(node, "ranges", NULL);
if (!prop)
return -EINVAL;
return 0;
}
/*
* fdt_scan_reserved_mem() - scan a single FDT node for reserved memory
*/
static int __init fdt_scan_reserved_mem(void)
{
int node, child;
const void *fdt = initial_boot_params;
node = fdt_path_offset(fdt, "/reserved-memory");
if (node < 0)
return -ENODEV;
if (__reserved_mem_check_root(node) != 0) {
pr_err("Reserved memory: unsupported node format, ignoring\n");
return -EINVAL;
}
fdt_for_each_subnode(child, fdt, node) {
const char *uname;
int err;
if (!of_fdt_device_is_available(fdt, child))
continue;
uname = fdt_get_name(fdt, child, NULL);
err = __reserved_mem_reserve_reg(child, uname);
if (err == -ENOENT && of_get_flat_dt_prop(child, "size", NULL))
fdt_reserved_mem_save_node(child, uname, 0, 0);
}
return 0;
}
/*
* fdt_reserve_elfcorehdr() - reserves memory for elf core header
*
* 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;
u64 base, size;
if (!initial_boot_params)
return;
/* Process header /memreserve/ fields */
for (n = 0; ; n++) {
fdt_get_mem_rsv(initial_boot_params, n, &base, &size);
if (!size)
break;
memblock_reserve(base, size);
}
fdt_scan_reserved_mem();
fdt_reserve_elfcorehdr();
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 */
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);
}
/**
* 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 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_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);
}
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;
}
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;
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);
__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)
{
const __be32 *prop;
int len;
if (!IS_ENABLED(CONFIG_CRASH_DUMP))
return;
pr_debug("Looking for elfcorehdr property... ");
prop = of_get_flat_dt_prop(node, "linux,elfcorehdr", &len);
if (!prop || (len < (dt_root_addr_cells + dt_root_size_cells)))
return;
elfcorehdr_addr = dt_mem_next_cell(dt_root_addr_cells, &prop);
elfcorehdr_size = dt_mem_next_cell(dt_root_size_cells, &prop);
pr_debug("elfcorehdr_start=0x%llx elfcorehdr_size=0x%llx\n",
elfcorehdr_addr, elfcorehdr_size);
}
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 two regions, low region and high region.
* To make compatibility with existing user-space and older kdump, the low
* region is always the last range of linux,usable-memory-range if exist.
*/
#define MAX_USABLE_RANGES 2
/**
* 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, *endp;
int len, i;
unsigned long node = chosen_node_offset;
if ((long)node < 0)
return;
pr_debug("Looking for usable-memory-range property... ");
prop = of_get_flat_dt_prop(node, "linux,usable-memory-range", &len);
if (!prop || (len % (dt_root_addr_cells + dt_root_size_cells)))
return;
endp = prop + (len / sizeof(__be32));
for (i = 0; i < MAX_USABLE_RANGES && prop < endp; i++) {
rgn[i].base = dt_mem_next_cell(dt_root_addr_cells, &prop);
rgn[i].size = dt_mem_next_cell(dt_root_size_cells, &prop);
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);
}
#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_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;
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 (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);
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;
const void *fdt = initial_boot_params;
fdt_for_each_subnode(node, fdt, 0) {
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)
continue;
if (!of_fdt_device_is_available(fdt, node))
continue;
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)
continue;
endp = reg + (l / sizeof(__be32));
hotpluggable = of_get_flat_dt_prop(node, "hotpluggable", NULL);
pr_debug("memory scan node %s, reg size %d,\n",
fdt_get_name(fdt, node, NULL), l);
while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) {
u64 base, size;
base = dt_mem_next_cell(dt_root_addr_cells, &reg);
size = dt_mem_next_cell(dt_root_size_cells, &reg);
if (size == 0)
continue;
pr_debug(" - %llx, %llx\n", base, size);
early_init_dt_add_memory_arch(base, size);
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 0;
}
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)
return -ENOENT;
chosen_node_offset = node;
early_init_dt_check_for_initrd(node);
early_init_dt_check_for_elfcorehdr(node);
/* Retrieve command line */
p = of_get_flat_dt_prop(node, "bootargs", &l);
if (p != NULL && l > 0)
strlcpy(cmdline, 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(cmdline, " ", COMMAND_LINE_SIZE);
strlcat(cmdline, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
#elif defined(CONFIG_CMDLINE_FORCE)
strlcpy(cmdline, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
#else
/* No arguments from boot loader, use kernel's cmdl*/
if (!((char *)cmdline)[0])
strlcpy(cmdline, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
#endif
#endif /* CONFIG_CMDLINE */
pr_debug("Command line is: %s\n", (char *)cmdline);
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));
}
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)
{
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;
/* Initialize {size,address}-cells info */
early_init_dt_scan_root();
/* 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();
}
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 */