[PATCH v5 03/11] drivers: of: add initialization code for dynamic reserved memory
Grant Likely
grant.likely at linaro.org
Wed Feb 26 07:09:17 EST 2014
On Fri, 21 Feb 2014 13:25:19 +0100, Marek Szyprowski <m.szyprowski at samsung.com> wrote:
> 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 at codeaurora.org>
>
> Signed-off-by: Marek Szyprowski <m.szyprowski at samsung.com>
Acked-by: Grant Likely <grant.likely at 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 12809e20ef71..eafe5805257a 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/string.h>
> #include <linux/errno.h>
> #include <linux/slab.h>
> @@ -449,7 +450,7 @@ 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)
> @@ -476,6 +477,10 @@ 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;
> }
> @@ -506,6 +511,7 @@ 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) {
> @@ -528,7 +534,9 @@ 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;
> @@ -544,6 +552,7 @@ 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..c7ca6a4a42d1
> --- /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 at samsung.com>
> + * Author: Josh Cartwright <joshc at 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_error("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 */
> --
> 1.7.9.5
>
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