This patch adds support for dynamically allocated reserved memory regions declared in device tree. Such regions are defined by 'size', 'alignment' and 'alloc-ranges' properties.
Based on previous code provided by Josh Cartwright joshc@codeaurora.org
Signed-off-by: Marek Szyprowski m.szyprowski@samsung.com Acked-by: Grant Likely grant.likely@linaro.org --- drivers/of/Kconfig | 6 ++ drivers/of/Makefile | 1 + drivers/of/fdt.c | 13 ++- drivers/of/of_reserved_mem.c | 188 +++++++++++++++++++++++++++++++++++++++ include/linux/of_reserved_mem.h | 21 +++++ 5 files changed, 227 insertions(+), 2 deletions(-) create mode 100644 drivers/of/of_reserved_mem.c create mode 100644 include/linux/of_reserved_mem.h
diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig index c6973f101a3e..30a7d87a8077 100644 --- a/drivers/of/Kconfig +++ b/drivers/of/Kconfig @@ -75,4 +75,10 @@ config OF_MTD depends on MTD def_bool y
+config OF_RESERVED_MEM + depends on OF_EARLY_FLATTREE + bool + help + Helpers to allow for reservation of memory regions + endmenu # OF diff --git a/drivers/of/Makefile b/drivers/of/Makefile index efd05102c405..ed9660adad77 100644 --- a/drivers/of/Makefile +++ b/drivers/of/Makefile @@ -9,3 +9,4 @@ obj-$(CONFIG_OF_MDIO) += of_mdio.o obj-$(CONFIG_OF_PCI) += of_pci.o obj-$(CONFIG_OF_PCI_IRQ) += of_pci_irq.o obj-$(CONFIG_OF_MTD) += of_mtd.o +obj-$(CONFIG_OF_RESERVED_MEM) += of_reserved_mem.o diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c index 819e11209718..510c0d8de8a0 100644 --- a/drivers/of/fdt.c +++ b/drivers/of/fdt.c @@ -15,6 +15,7 @@ #include <linux/module.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> @@ -450,7 +451,7 @@ static int __init __reserved_mem_reserve_reg(unsigned long node, phys_addr_t base, size; unsigned long len; __be32 *prop; - int nomap; + int nomap, first = 1;
prop = of_get_flat_dt_prop(node, "reg", &len); if (!prop) @@ -477,6 +478,10 @@ static int __init __reserved_mem_reserve_reg(unsigned long node, 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; } @@ -512,6 +517,7 @@ static int __init __fdt_scan_reserved_mem(unsigned long node, const char *uname, { static int found; const char *status; + int err;
if (!found && depth == 1 && strcmp(uname, "reserved-memory") == 0) { if (__reserved_mem_check_root(node) != 0) { @@ -534,7 +540,9 @@ static int __init __fdt_scan_reserved_mem(unsigned long node, const char *uname, if (status && strcmp(status, "okay") != 0 && strcmp(status, "ok") != 0) return 0;
- __reserved_mem_reserve_reg(node, uname); + err = __reserved_mem_reserve_reg(node, uname); + if (err == -ENOENT && of_get_flat_dt_prop(node, "size", NULL)) + fdt_reserved_mem_save_node(node, uname, 0, 0);
/* scan next node */ return 0; @@ -550,6 +558,7 @@ static int __init __fdt_scan_reserved_mem(unsigned long node, const char *uname, void __init early_init_fdt_scan_reserved_mem(void) { of_scan_flat_dt(__fdt_scan_reserved_mem, NULL); + fdt_init_reserved_mem(); }
/** diff --git a/drivers/of/of_reserved_mem.c b/drivers/of/of_reserved_mem.c new file mode 100644 index 000000000000..69b811779585 --- /dev/null +++ b/drivers/of/of_reserved_mem.c @@ -0,0 +1,188 @@ +/* + * 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; + unsigned long len; + __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; +} + +/** + * 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 err = 0; + + if (rmem->size == 0) + err = __reserved_mem_alloc_size(node, rmem->name, + &rmem->base, &rmem->size); + } +} diff --git a/include/linux/of_reserved_mem.h b/include/linux/of_reserved_mem.h new file mode 100644 index 000000000000..89226ed7d954 --- /dev/null +++ b/include/linux/of_reserved_mem.h @@ -0,0 +1,21 @@ +#ifndef __OF_RESERVED_MEM_H +#define __OF_RESERVED_MEM_H + +struct reserved_mem { + const char *name; + unsigned long fdt_node; + phys_addr_t base; + phys_addr_t size; +}; + +#ifdef CONFIG_OF_RESERVED_MEM +void fdt_init_reserved_mem(void); +void fdt_reserved_mem_save_node(unsigned long node, const char *uname, + phys_addr_t base, phys_addr_t size); +#else +static inline void fdt_init_reserved_mem(void) { } +static inline void fdt_reserved_mem_save_node(unsigned long node, + const char *uname, phys_addr_t base, phys_addr_t size) { } +#endif + +#endif /* __OF_RESERVED_MEM_H */