v4.19.13 snapshot.
diff --git a/drivers/of/of_reserved_mem.c b/drivers/of/of_reserved_mem.c
new file mode 100644
index 0000000..895c83e
--- /dev/null
+++ b/drivers/of/of_reserved_mem.c
@@ -0,0 +1,421 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Device tree based initialization code for reserved memory.
+ *
+ * Copyright (c) 2013, 2015 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>
+ */
+
+#define pr_fmt(fmt) "OF: reserved mem: " fmt
+
+#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>
+#include <linux/sort.h>
+#include <linux/slab.h>
+
+#define MAX_RESERVED_REGIONS 32
+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)
+{
+ phys_addr_t base;
+ /*
+ * We use __memblock_alloc_base() because memblock_alloc_base()
+ * panic()s on allocation failure.
+ */
+ end = !end ? MEMBLOCK_ALLOC_ANYWHERE : end;
+ 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("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("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("invalid alignment property in '%s' node.\n",
+ uname);
+ return -EINVAL;
+ }
+ align = dt_mem_next_cell(dt_root_addr_cells, &prop);
+ }
+
+ /* Need adjust the alignment to satisfy the CMA requirement */
+ if (IS_ENABLED(CONFIG_CMA)
+ && of_flat_dt_is_compatible(node, "shared-dma-pool")
+ && of_get_flat_dt_prop(node, "reusable", NULL)
+ && !of_get_flat_dt_prop(node, "no-map", NULL)) {
+ unsigned long order =
+ max_t(unsigned long, MAX_ORDER - 1, pageblock_order);
+
+ align = max(align, (phys_addr_t)PAGE_SIZE << order);
+ }
+
+ prop = of_get_flat_dt_prop(node, "alloc-ranges", &len);
+ if (prop) {
+
+ if (len % t_len != 0) {
+ pr_err("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("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("allocated memory for '%s' node: base %pa, size %ld MiB\n",
+ uname, &base, (unsigned long)size / SZ_1M);
+ }
+
+ if (base == 0) {
+ pr_info("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("initialized node %s, compatible id %s\n",
+ rmem->name, compat);
+ return 0;
+ }
+ }
+ return -ENOENT;
+}
+
+static int __init __rmem_cmp(const void *a, const void *b)
+{
+ const struct reserved_mem *ra = a, *rb = b;
+
+ if (ra->base < rb->base)
+ return -1;
+
+ if (ra->base > rb->base)
+ return 1;
+
+ return 0;
+}
+
+static void __init __rmem_check_for_overlap(void)
+{
+ int i;
+
+ if (reserved_mem_count < 2)
+ return;
+
+ sort(reserved_mem, reserved_mem_count, sizeof(reserved_mem[0]),
+ __rmem_cmp, NULL);
+ for (i = 0; i < reserved_mem_count - 1; i++) {
+ struct reserved_mem *this, *next;
+
+ this = &reserved_mem[i];
+ next = &reserved_mem[i + 1];
+ if (!(this->base && next->base))
+ continue;
+ if (this->base + this->size > next->base) {
+ phys_addr_t this_end, next_end;
+
+ this_end = this->base + this->size;
+ next_end = next->base + next->size;
+ pr_err("OVERLAP DETECTED!\n%s (%pa--%pa) overlaps with %s (%pa--%pa)\n",
+ this->name, &this->base, &this_end,
+ next->name, &next->base, &next_end);
+ }
+ }
+}
+
+/**
+ * fdt_init_reserved_mem - allocate and init all saved reserved memory regions
+ */
+void __init fdt_init_reserved_mem(void)
+{
+ int i;
+
+ /* check for overlapping reserved regions */
+ __rmem_check_for_overlap();
+
+ 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;
+}
+
+struct rmem_assigned_device {
+ struct device *dev;
+ struct reserved_mem *rmem;
+ struct list_head list;
+};
+
+static LIST_HEAD(of_rmem_assigned_device_list);
+static DEFINE_MUTEX(of_rmem_assigned_device_mutex);
+
+/**
+ * of_reserved_mem_device_init_by_idx() - assign reserved memory region to
+ * given device
+ * @dev: Pointer to the device to configure
+ * @np: Pointer to the device_node with 'reserved-memory' property
+ * @idx: Index of selected region
+ *
+ * This function assigns respective DMA-mapping operations based on reserved
+ * memory region specified by 'memory-region' property in @np node to the @dev
+ * device. When driver needs to use more than one reserved memory region, it
+ * should allocate child devices and initialize regions by name for each of
+ * child device.
+ *
+ * Returns error code or zero on success.
+ */
+int of_reserved_mem_device_init_by_idx(struct device *dev,
+ struct device_node *np, int idx)
+{
+ struct rmem_assigned_device *rd;
+ struct device_node *target;
+ struct reserved_mem *rmem;
+ int ret;
+
+ if (!np || !dev)
+ return -EINVAL;
+
+ target = of_parse_phandle(np, "memory-region", idx);
+ if (!target)
+ return -ENODEV;
+
+ rmem = __find_rmem(target);
+ of_node_put(target);
+
+ if (!rmem || !rmem->ops || !rmem->ops->device_init)
+ return -EINVAL;
+
+ rd = kmalloc(sizeof(struct rmem_assigned_device), GFP_KERNEL);
+ if (!rd)
+ return -ENOMEM;
+
+ ret = rmem->ops->device_init(rmem, dev);
+ if (ret == 0) {
+ rd->dev = dev;
+ rd->rmem = rmem;
+
+ mutex_lock(&of_rmem_assigned_device_mutex);
+ list_add(&rd->list, &of_rmem_assigned_device_list);
+ mutex_unlock(&of_rmem_assigned_device_mutex);
+ /* ensure that dma_ops is set for virtual devices
+ * using reserved memory
+ */
+ of_dma_configure(dev, np, true);
+
+ dev_info(dev, "assigned reserved memory node %s\n", rmem->name);
+ } else {
+ kfree(rd);
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(of_reserved_mem_device_init_by_idx);
+
+/**
+ * of_reserved_mem_device_release() - release reserved memory device structures
+ * @dev: Pointer to the device to deconfigure
+ *
+ * This function releases structures allocated for memory region handling for
+ * the given device.
+ */
+void of_reserved_mem_device_release(struct device *dev)
+{
+ struct rmem_assigned_device *rd;
+ struct reserved_mem *rmem = NULL;
+
+ mutex_lock(&of_rmem_assigned_device_mutex);
+ list_for_each_entry(rd, &of_rmem_assigned_device_list, list) {
+ if (rd->dev == dev) {
+ rmem = rd->rmem;
+ list_del(&rd->list);
+ kfree(rd);
+ break;
+ }
+ }
+ mutex_unlock(&of_rmem_assigned_device_mutex);
+
+ if (!rmem || !rmem->ops || !rmem->ops->device_release)
+ return;
+
+ rmem->ops->device_release(rmem, dev);
+}
+EXPORT_SYMBOL_GPL(of_reserved_mem_device_release);
+
+/**
+ * of_reserved_mem_lookup() - acquire reserved_mem from a device node
+ * @np: node pointer of the desired reserved-memory region
+ *
+ * This function allows drivers to acquire a reference to the reserved_mem
+ * struct based on a device node handle.
+ *
+ * Returns a reserved_mem reference, or NULL on error.
+ */
+struct reserved_mem *of_reserved_mem_lookup(struct device_node *np)
+{
+ const char *name;
+ int i;
+
+ if (!np->full_name)
+ return NULL;
+
+ name = kbasename(np->full_name);
+ for (i = 0; i < reserved_mem_count; i++)
+ if (!strcmp(reserved_mem[i].name, name))
+ return &reserved_mem[i];
+
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(of_reserved_mem_lookup);