// 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> #define MAX_RESERVED_REGIONS 32 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; end = !end ? MEMBLOCK_ALLOC_ANYWHERE : end; align = !align ? SMP_CACHE_BYTES : align; base = memblock_find_in_range(start, end, size, align); if (!base) return -ENOMEM; *res_base = base; if (nomap) return memblock_remove(base, size); return memblock_reserve(base, size); } /** * res_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 all defined regions.\n"); return; } rmem->fdt_node = node; rmem->name = uname; rmem->base = base; rmem->size = size; reserved_mem_count++; return; } /** * res_mem_alloc_size() - allocate reserved memory described by 'size', 'align' * 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; int 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); nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL; 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); } /* 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) && !of_get_flat_dt_prop(node, "no-map", NULL)) { unsigned long order = max_t(unsigned long, MAX_ORDER - 1, pageblock_order); align = max(align, (phys_addr_t)PAGE_SIZE << order); } 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 %ld 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 %ld 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); /** * res_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; 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 && next->base)) continue; 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; int 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); memblock_free(rmem->base, rmem->size); if (nomap) memblock_add(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_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; struct reserved_mem *rmem = NULL; mutex_lock(&of_rmem_assigned_device_mutex); list_for_each_entry(rd, &of_rmem_assigned_device_list, list) { if (rd->dev == dev) { rmem = rd->rmem; list_del(&rd->list); kfree(rd); break; } } mutex_unlock(&of_rmem_assigned_device_mutex); if (!rmem || !rmem->ops || !rmem->ops->device_release) return; rmem->ops->device_release(rmem, dev); } 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);