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@xxxxxxxxxxxxxx>
Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
---
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@xxxxxxxxxxx>
+ * Author: Josh Cartwright <joshc@xxxxxxxxxxxxxx>
+ *
+ * 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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