diff options
Diffstat (limited to 'drivers/of/of_reserved_mem.c')
| -rw-r--r-- | drivers/of/of_reserved_mem.c | 449 |
1 files changed, 449 insertions, 0 deletions
diff --git a/drivers/of/of_reserved_mem.c b/drivers/of/of_reserved_mem.c new file mode 100644 index 000000000..f90975e00 --- /dev/null +++ b/drivers/of/of_reserved_mem.c @@ -0,0 +1,449 @@ +// 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_err("failed to allocate memory for node '%s': size %lu MiB\n", + uname, (unsigned long)(size / SZ_1M)); + 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); |