// SPDX-License-Identifier: GPL-2.0+
/*
* Device tree based initialization code for reserved memory.
*
* Copyright (c) 2013, 2015 The Linux Foundation. All Rights Reserved.
* Copyright (c) 2013,2014 Samsung Electronics Co., Ltd.
* http://www.samsung.com
* Author: Marek Szyprowski <m.szyprowski@samsung.com>
* Author: Josh Cartwright <joshc@codeaurora.org>
*/
#define pr_fmt(fmt) "OF: reserved mem: " fmt
#include <linux/err.h>
#include <linux/of.h>
#include <linux/of_fdt.h>
#include <linux/of_platform.h>
#include <linux/mm.h>
#include <linux/sizes.h>
#include <linux/of_reserved_mem.h>
#include <linux/sort.h>
#include <linux/slab.h>
#include <linux/memblock.h>
#include <linux/kmemleak.h>
#include <linux/cma.h>
#include "of_private.h"
#define MAX_RESERVED_REGIONS 64
static struct reserved_mem reserved_mem[MAX_RESERVED_REGIONS];
static int reserved_mem_count;
static int __init early_init_dt_alloc_reserved_memory_arch(phys_addr_t size,
phys_addr_t align, phys_addr_t start, phys_addr_t end, bool nomap,
phys_addr_t *res_base)
{
phys_addr_t base;
int err = 0;
end = !end ? MEMBLOCK_ALLOC_ANYWHERE : end;
align = !align ? SMP_CACHE_BYTES : align;
base = memblock_phys_alloc_range(size, align, start, end);
if (!base)
return -ENOMEM;
*res_base = base;
if (nomap) {
err = memblock_mark_nomap(base, size);
if (err)
memblock_phys_free(base, size);
kmemleak_ignore_phys(base);
}
return err;
}
/*
* fdt_reserved_mem_save_node() - save fdt node for second pass initialization
*/
void __init fdt_reserved_mem_save_node(unsigned long node, const char *uname,
phys_addr_t base, phys_addr_t size)
{
struct reserved_mem *rmem = &reserved_mem[reserved_mem_count];
if (reserved_mem_count == ARRAY_SIZE(reserved_mem)) {
pr_err("not enough space for all defined regions.\n");
return;
}
rmem->fdt_node = node;
rmem->name = uname;
rmem->base = base;
rmem->size = size;
reserved_mem_count++;
return;
}
/*
* __reserved_mem_alloc_size() - allocate reserved memory described by
* 'size', 'alignment' and 'alloc-ranges' properties.
*/
static int __init __reserved_mem_alloc_size(unsigned long node,
const char *uname, phys_addr_t *res_base, phys_addr_t *res_size)
{
int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
phys_addr_t start = 0, end = 0;
phys_addr_t base = 0, align = 0, size;
int len;
const __be32 *prop;
bool nomap;
int ret;
prop = of_get_flat_dt_prop(node, "size", &len);
if (!prop)
return -EINVAL;
if (len != dt_root_size_cells * sizeof(__be32)) {
pr_err("invalid size property in '%s' node.\n", uname);
return -EINVAL;
}
size = dt_mem_next_cell(dt_root_size_cells, &prop);
prop = of_get_flat_dt_prop(node, "alignment", &len);
if (prop) {
if (len != dt_root_addr_cells * sizeof(__be32)) {
pr_err("invalid alignment property in '%s' node.\n",
uname);
return -EINVAL;
}
align = dt_mem_next_cell(dt_root_addr_cells, &prop);
}
nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
/* Need adjust the alignment to satisfy the CMA requirement */
if (IS_ENABLED(CONFIG_CMA)
&& of_flat_dt_is_compatible(node, "shared-dma-pool")
&& of_get_flat_dt_prop(node, "reusable", NULL)
&& !nomap)
align = max_t(phys_addr_t, align, CMA_MIN_ALIGNMENT_BYTES);
prop = of_get_flat_dt_prop(node, "alloc-ranges", &len);
if (prop) {
if (len % t_len != 0) {
pr_err("invalid alloc-ranges property in '%s', skipping node.\n",
uname);
return -EINVAL;
}
base = 0;
while (len > 0) {
start = dt_mem_next_cell(dt_root_addr_cells, &prop);
end = start + dt_mem_next_cell(dt_root_size_cells,
&prop);
ret = early_init_dt_alloc_reserved_memory_arch(size,
align, start, end, nomap, &base);
if (ret == 0) {
pr_debug("allocated memory for '%s' node: base %pa, size %lu MiB\n",
uname, &base,
(unsigned long)(size / SZ_1M));
break;
}
len -= t_len;
}
} else {
ret = early_init_dt_alloc_reserved_memory_arch(size, align,
0, 0, nomap, &base);
if (ret == 0)
pr_debug("allocated memory for '%s' node: base %pa, size %lu MiB\n",
uname, &base, (unsigned long)(size / SZ_1M));
}
if (base == 0) {
pr_info("failed to allocate memory for node '%s'\n", uname);
return -ENOMEM;
}
*res_base = base;
*res_size = size;
return 0;
}
static const struct of_device_id __rmem_of_table_sentinel
__used __section("__reservedmem_of_table_end");
/*
* __reserved_mem_init_node() - call region specific reserved memory init code
*/
static int __init __reserved_mem_init_node(struct reserved_mem *rmem)
{
extern const struct of_device_id __reservedmem_of_table[];
const struct of_device_id *i;
int ret = -ENOENT;
for (i = __reservedmem_of_table; i < &__rmem_of_table_sentinel; i++) {
reservedmem_of_init_fn initfn = i->data;
const char *compat = i->compatible;
if (!of_flat_dt_is_compatible(rmem->fdt_node, compat))
continue;
ret = initfn(rmem);
if (ret == 0) {
pr_info("initialized node %s, compatible id %s\n",
rmem->name, compat);
break;
}
}
return ret;
}
static int __init __rmem_cmp(const void *a, const void *b)
{
const struct reserved_mem *ra = a, *rb = b;
if (ra->base < rb->base)
return -1;
if (ra->base > rb->base)
return 1;
/*
* Put the dynamic allocations (address == 0, size == 0) before static
* allocations at address 0x0 so that overlap detection works
* correctly.
*/
if (ra->size < rb->size)
return -1;
if (ra->size > rb->size)
return 1;
return 0;
}
static void __init __rmem_check_for_overlap(void)
{
int i;
if (reserved_mem_count < 2)
return;
sort(reserved_mem, reserved_mem_count, sizeof(reserved_mem[0]),
__rmem_cmp, NULL);
for (i = 0; i < reserved_mem_count - 1; i++) {
struct reserved_mem *this, *next;
this = &reserved_mem[i];
next = &reserved_mem[i + 1];
if (this->base + this->size > next->base) {
phys_addr_t this_end, next_end;
this_end = this->base + this->size;
next_end = next->base + next->size;
pr_err("OVERLAP DETECTED!\n%s (%pa--%pa) overlaps with %s (%pa--%pa)\n",
this->name, &this->base, &this_end,
next->name, &next->base, &next_end);
}
}
}
/**
* fdt_init_reserved_mem() - allocate and init all saved reserved memory regions
*/
void __init fdt_init_reserved_mem(void)
{
int i;
/* check for overlapping reserved regions */
__rmem_check_for_overlap();
for (i = 0; i < reserved_mem_count; i++) {
struct reserved_mem *rmem = &reserved_mem[i];
unsigned long node = rmem->fdt_node;
int len;
const __be32 *prop;
int err = 0;
bool nomap;
nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
prop = of_get_flat_dt_prop(node, "phandle", &len);
if (!prop)
prop = of_get_flat_dt_prop(node, "linux,phandle", &len);
if (prop)
rmem->phandle = of_read_number(prop, len/4);
if (rmem->size == 0)
err = __reserved_mem_alloc_size(node, rmem->name,
&rmem->base, &rmem->size);
if (err == 0) {
err = __reserved_mem_init_node(rmem);
if (err != 0 && err != -ENOENT) {
pr_info("node %s compatible matching fail\n",
rmem->name);
if (nomap)
memblock_clear_nomap(rmem->base, rmem->size);
else
memblock_phys_free(rmem->base,
rmem->size);
}
}
}
}
static inline struct reserved_mem *__find_rmem(struct device_node *node)
{
unsigned int i;
if (!node->phandle)
return NULL;
for (i = 0; i < reserved_mem_count; i++)
if (reserved_mem[i].phandle == node->phandle)
return &reserved_mem[i];
return NULL;
}
struct rmem_assigned_device {
struct device *dev;
struct reserved_mem *rmem;
struct list_head list;
};
static LIST_HEAD(of_rmem_assigned_device_list);
static DEFINE_MUTEX(of_rmem_assigned_device_mutex);
/**
* of_reserved_mem_device_init_by_idx() - assign reserved memory region to
* given device
* @dev: Pointer to the device to configure
* @np: Pointer to the device_node with 'reserved-memory' property
* @idx: Index of selected region
*
* This function assigns respective DMA-mapping operations based on reserved
* memory region specified by 'memory-region' property in @np node to the @dev
* device. When driver needs to use more than one reserved memory region, it
* should allocate child devices and initialize regions by name for each of
* child device.
*
* Returns error code or zero on success.
*/
int of_reserved_mem_device_init_by_idx(struct device *dev,
struct device_node *np, int idx)
{
struct rmem_assigned_device *rd;
struct device_node *target;
struct reserved_mem *rmem;
int ret;
if (!np || !dev)
return -EINVAL;
target = of_parse_phandle(np, "memory-region", idx);
if (!target)
return -ENODEV;
if (!of_device_is_available(target)) {
of_node_put(target);
return 0;
}
rmem = __find_rmem(target);
of_node_put(target);
if (!rmem || !rmem->ops || !rmem->ops->device_init)
return -EINVAL;
rd = kmalloc(sizeof(struct rmem_assigned_device), GFP_KERNEL);
if (!rd)
return -ENOMEM;
ret = rmem->ops->device_init(rmem, dev);
if (ret == 0) {
rd->dev = dev;
rd->rmem = rmem;
mutex_lock(&of_rmem_assigned_device_mutex);
list_add(&rd->list, &of_rmem_assigned_device_list);
mutex_unlock(&of_rmem_assigned_device_mutex);
dev_info(dev, "assigned reserved memory node %s\n", rmem->name);
} else {
kfree(rd);
}
return ret;
}
EXPORT_SYMBOL_GPL(of_reserved_mem_device_init_by_idx);
/**
* of_reserved_mem_device_init_by_name() - assign named reserved memory region
* to given device
* @dev: pointer to the device to configure
* @np: pointer to the device node with 'memory-region' property
* @name: name of the selected memory region
*
* Returns: 0 on success or a negative error-code on failure.
*/
int of_reserved_mem_device_init_by_name(struct device *dev,
struct device_node *np,
const char *name)
{
int idx = of_property_match_string(np, "memory-region-names", name);
return of_reserved_mem_device_init_by_idx(dev, np, idx);
}
EXPORT_SYMBOL_GPL(of_reserved_mem_device_init_by_name);
/**
* of_reserved_mem_device_release() - release reserved memory device structures
* @dev: Pointer to the device to deconfigure
*
* This function releases structures allocated for memory region handling for
* the given device.
*/
void of_reserved_mem_device_release(struct device *dev)
{
struct rmem_assigned_device *rd, *tmp;
LIST_HEAD(release_list);
mutex_lock(&of_rmem_assigned_device_mutex);
list_for_each_entry_safe(rd, tmp, &of_rmem_assigned_device_list, list) {
if (rd->dev == dev)
list_move_tail(&rd->list, &release_list);
}
mutex_unlock(&of_rmem_assigned_device_mutex);
list_for_each_entry_safe(rd, tmp, &release_list, list) {
if (rd->rmem && rd->rmem->ops && rd->rmem->ops->device_release)
rd->rmem->ops->device_release(rd->rmem, dev);
kfree(rd);
}
}
EXPORT_SYMBOL_GPL(of_reserved_mem_device_release);
/**
* of_reserved_mem_lookup() - acquire reserved_mem from a device node
* @np: node pointer of the desired reserved-memory region
*
* This function allows drivers to acquire a reference to the reserved_mem
* struct based on a device node handle.
*
* Returns a reserved_mem reference, or NULL on error.
*/
struct reserved_mem *of_reserved_mem_lookup(struct device_node *np)
{
const char *name;
int i;
if (!np->full_name)
return NULL;
name = kbasename(np->full_name);
for (i = 0; i < reserved_mem_count; i++)
if (!strcmp(reserved_mem[i].name, name))
return &reserved_mem[i];
return NULL;
}
EXPORT_SYMBOL_GPL(of_reserved_mem_lookup);