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Diffstat (limited to 'drivers/of/of_reserved_mem.c')
-rw-r--r--drivers/of/of_reserved_mem.c293
1 files changed, 293 insertions, 0 deletions
diff --git a/drivers/of/of_reserved_mem.c b/drivers/of/of_reserved_mem.c
new file mode 100644
index 000000000..726ebe792
--- /dev/null
+++ b/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);