diff options
Diffstat (limited to 'kernel/drivers/of/of_reserved_mem.c')
-rw-r--r-- | kernel/drivers/of/of_reserved_mem.c | 293 |
1 files changed, 293 insertions, 0 deletions
diff --git a/kernel/drivers/of/of_reserved_mem.c b/kernel/drivers/of/of_reserved_mem.c new file mode 100644 index 000000000..726ebe792 --- /dev/null +++ b/kernel/drivers/of/of_reserved_mem.c @@ -0,0 +1,293 @@ +/* + * Device tree based initialization code for reserved memory. + * + * Copyright (c) 2013, 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> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of the + * License or (at your optional) any later version of the license. + */ + +#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> + +#define MAX_RESERVED_REGIONS 16 +static struct reserved_mem reserved_mem[MAX_RESERVED_REGIONS]; +static int reserved_mem_count; + +#if defined(CONFIG_HAVE_MEMBLOCK) +#include <linux/memblock.h> +int __init __weak 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) +{ + /* + * We use __memblock_alloc_base() because memblock_alloc_base() + * panic()s on allocation failure. + */ + phys_addr_t base = __memblock_alloc_base(size, align, end); + if (!base) + return -ENOMEM; + + /* + * Check if the allocated region fits in to start..end window + */ + if (base < start) { + memblock_free(base, size); + return -ENOMEM; + } + + *res_base = base; + if (nomap) + return memblock_remove(base, size); + return 0; +} +#else +int __init __weak 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) +{ + pr_err("Reserved memory not supported, ignoring region 0x%llx%s\n", + size, nomap ? " (nomap)" : ""); + return -ENOSYS; +} +#endif + +/** + * 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("Reserved memory: 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("Reserved memory: 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("Reserved memory: invalid alignment property in '%s' node.\n", + uname); + return -EINVAL; + } + align = dt_mem_next_cell(dt_root_addr_cells, &prop); + } + + prop = of_get_flat_dt_prop(node, "alloc-ranges", &len); + if (prop) { + + if (len % t_len != 0) { + pr_err("Reserved memory: 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("Reserved memory: 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("Reserved memory: allocated memory for '%s' node: base %pa, size %ld MiB\n", + uname, &base, (unsigned long)size / SZ_1M); + } + + if (base == 0) { + pr_info("Reserved memory: 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; + + 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; + + if (initfn(rmem) == 0) { + pr_info("Reserved memory: initialized node %s, compatible id %s\n", + rmem->name, compat); + return 0; + } + } + return -ENOENT; +} + +/** + * fdt_init_reserved_mem - allocate and init all saved reserved memory regions + */ +void __init fdt_init_reserved_mem(void) +{ + int i; + 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; + + 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) + __reserved_mem_init_node(rmem); + } +} + +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; +} + +/** + * of_reserved_mem_device_init() - assign reserved memory region to given device + * + * This function assign memory region pointed by "memory-region" device tree + * property to the given device. + */ +int of_reserved_mem_device_init(struct device *dev) +{ + struct reserved_mem *rmem; + struct device_node *np; + int ret; + + np = of_parse_phandle(dev->of_node, "memory-region", 0); + if (!np) + return -ENODEV; + + rmem = __find_rmem(np); + of_node_put(np); + + if (!rmem || !rmem->ops || !rmem->ops->device_init) + return -EINVAL; + + ret = rmem->ops->device_init(rmem, dev); + if (ret == 0) + dev_info(dev, "assigned reserved memory node %s\n", rmem->name); + + return ret; +} +EXPORT_SYMBOL_GPL(of_reserved_mem_device_init); + +/** + * of_reserved_mem_device_release() - release reserved memory device structures + * + * This function releases structures allocated for memory region handling for + * the given device. + */ +void of_reserved_mem_device_release(struct device *dev) +{ + struct reserved_mem *rmem; + struct device_node *np; + + np = of_parse_phandle(dev->of_node, "memory-region", 0); + if (!np) + return; + + rmem = __find_rmem(np); + of_node_put(np); + + if (!rmem || !rmem->ops || !rmem->ops->device_release) + return; + + rmem->ops->device_release(rmem, dev); +} +EXPORT_SYMBOL_GPL(of_reserved_mem_device_release); |