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-rw-r--r--Documentation/devicetree/bindings/memory.txt168
-rw-r--r--arch/arm/include/asm/dma-contiguous.h1
-rw-r--r--arch/arm/mm/init.c3
-rw-r--r--arch/x86/include/asm/dma-contiguous.h1
-rw-r--r--drivers/base/dma-contiguous.c119
-rw-r--r--drivers/of/Kconfig6
-rw-r--r--drivers/of/Makefile1
-rw-r--r--drivers/of/fdt.c76
-rw-r--r--drivers/of/of_reserved_mem.c175
-rw-r--r--drivers/of/platform.c4
-rw-r--r--include/asm-generic/dma-contiguous.h28
-rw-r--r--include/linux/device.h2
-rw-r--r--include/linux/dma-contiguous.h62
-rw-r--r--include/linux/of_fdt.h3
-rw-r--r--include/linux/of_reserved_mem.h14
15 files changed, 555 insertions, 108 deletions
diff --git a/Documentation/devicetree/bindings/memory.txt b/Documentation/devicetree/bindings/memory.txt
new file mode 100644
index 0000000..eb24693
--- /dev/null
+++ b/Documentation/devicetree/bindings/memory.txt
@@ -0,0 +1,168 @@
+*** Memory binding ***
+
+The /memory node provides basic information about the address and size
+of the physical memory. This node is usually filled or updated by the
+bootloader, depending on the actual memory configuration of the given
+hardware.
+
+The memory layout is described by the following node:
+
+/ {
+ #address-cells = <(n)>;
+ #size-cells = <(m)>;
+ memory {
+ device_type = "memory";
+ reg = <(baseaddr1) (size1)
+ (baseaddr2) (size2)
+ ...
+ (baseaddrN) (sizeN)>;
+ };
+ ...
+};
+
+A memory node follows the typical device tree rules for "reg" property:
+n: number of cells used to store base address value
+m: number of cells used to store size value
+baseaddrX: defines a base address of the defined memory bank
+sizeX: the size of the defined memory bank
+
+
+More than one memory bank can be defined.
+
+
+*** Reserved memory regions ***
+
+In /memory/reserved-memory node one can create child nodes describing
+particular reserved (excluded from normal use) memory regions. Such
+memory regions are usually designed for the special usage by various
+device drivers. A good example are contiguous memory allocations or
+memory sharing with other operating system on the same hardware board.
+Those special memory regions might depend on the board configuration and
+devices used on the target system.
+
+Parameters for each memory region can be encoded into the device tree
+with the following convention:
+
+[(label):] (name) {
+ compatible = "linux,contiguous-memory-region", "reserved-memory-region";
+ reg = <(address) (size)>;
+ (linux,default-contiguous-region);
+};
+
+compatible: one or more of:
+ - "linux,contiguous-memory-region" - enables binding of this
+ region to Contiguous Memory Allocator (special region for
+ contiguous memory allocations, shared with movable system
+ memory, Linux kernel-specific).
+ - "reserved-memory-region" - compatibility is defined, given
+ region is assigned for exclusive usage for by the respective
+ devices.
+
+reg: standard property defining the base address and size of
+ the memory region
+
+linux,default-contiguous-region: property indicating that the region
+ is the default region for all contiguous memory
+ allocations, Linux specific (optional)
+
+It is optional to specify the base address, so if one wants to use
+autoconfiguration of the base address, '0' can be specified as a base
+address in the 'reg' property.
+
+The /memory/reserved-memory node must contain the same #address-cells
+and #size-cells value as the root node.
+
+
+*** Device node's properties ***
+
+Once regions in the /memory/reserved-memory node have been defined, they
+may be referenced by other device nodes. Bindings that wish to reference
+memory regions should explicitly document their use of the following
+property:
+
+memory-region = <&phandle_to_defined_region>;
+
+This property indicates that the device driver should use the memory
+region pointed by the given phandle.
+
+
+*** Example ***
+
+This example defines a memory consisting of 4 memory banks. 3 contiguous
+regions are defined for Linux kernel, one default of all device drivers
+(named contig_mem, placed at 0x72000000, 64MiB), one dedicated to the
+framebuffer device (labelled display_mem, placed at 0x78000000, 8MiB)
+and one for multimedia processing (labelled multimedia_mem, placed at
+0x77000000, 64MiB). 'display_mem' region is then assigned to fb@12300000
+device for DMA memory allocations (Linux kernel drivers will use CMA is
+available or dma-exclusive usage otherwise). 'multimedia_mem' is
+assigned to scaler@12500000 and codec@12600000 devices for contiguous
+memory allocations when CMA driver is enabled.
+
+The reason for creating a separate region for framebuffer device is to
+match the framebuffer base address to the one configured by bootloader,
+so once Linux kernel drivers starts no glitches on the displayed boot
+logo appears. Scaller and codec drivers should share the memory
+allocations.
+
+/ {
+ #address-cells = <1>;
+ #size-cells = <1>;
+
+ /* ... */
+
+ memory {
+ reg = <0x40000000 0x10000000
+ 0x50000000 0x10000000
+ 0x60000000 0x10000000
+ 0x70000000 0x10000000>;
+
+ reserved-memory {
+ #address-cells = <1>;
+ #size-cells = <1>;
+
+ /*
+ * global autoconfigured region for contiguous allocations
+ * (used only with Contiguous Memory Allocator)
+ */
+ contig_region@0 {
+ compatible = "linux,contiguous-memory-region";
+ reg = <0x0 0x4000000>;
+ linux,default-contiguous-region;
+ };
+
+ /*
+ * special region for framebuffer
+ */
+ display_region: region@78000000 {
+ compatible = "linux,contiguous-memory-region", "reserved-memory-region";
+ reg = <0x78000000 0x800000>;
+ };
+
+ /*
+ * special region for multimedia processing devices
+ */
+ multimedia_region: region@77000000 {
+ compatible = "linux,contiguous-memory-region";
+ reg = <0x77000000 0x4000000>;
+ };
+ };
+ };
+
+ /* ... */
+
+ fb0: fb@12300000 {
+ status = "okay";
+ memory-region = <&display_region>;
+ };
+
+ scaler: scaler@12500000 {
+ status = "okay";
+ memory-region = <&multimedia_region>;
+ };
+
+ codec: codec@12600000 {
+ status = "okay";
+ memory-region = <&multimedia_region>;
+ };
+};
diff --git a/arch/arm/include/asm/dma-contiguous.h b/arch/arm/include/asm/dma-contiguous.h
index e072bb2..4f8e9e5 100644
--- a/arch/arm/include/asm/dma-contiguous.h
+++ b/arch/arm/include/asm/dma-contiguous.h
@@ -5,7 +5,6 @@
#ifdef CONFIG_DMA_CMA
#include <linux/types.h>
-#include <asm-generic/dma-contiguous.h>
void dma_contiguous_early_fixup(phys_addr_t base, unsigned long size);
diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c
index 2958e74..7b0cb3b 100644
--- a/arch/arm/mm/init.c
+++ b/arch/arm/mm/init.c
@@ -17,6 +17,7 @@
#include <linux/nodemask.h>
#include <linux/initrd.h>
#include <linux/of_fdt.h>
+#include <linux/of_reserved_mem.h>
#include <linux/highmem.h>
#include <linux/gfp.h>
#include <linux/memblock.h>
@@ -378,6 +379,8 @@ void __init arm_memblock_init(struct meminfo *mi,
if (mdesc->reserve)
mdesc->reserve();
+ early_init_dt_scan_reserved_mem();
+
/*
* reserve memory for DMA contigouos allocations,
* must come from DMA area inside low memory
diff --git a/arch/x86/include/asm/dma-contiguous.h b/arch/x86/include/asm/dma-contiguous.h
index c092416..b4b38ba 100644
--- a/arch/x86/include/asm/dma-contiguous.h
+++ b/arch/x86/include/asm/dma-contiguous.h
@@ -4,7 +4,6 @@
#ifdef __KERNEL__
#include <linux/types.h>
-#include <asm-generic/dma-contiguous.h>
static inline void
dma_contiguous_early_fixup(phys_addr_t base, unsigned long size) { }
diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c
index 6c9cdaa..99802d6f 100644
--- a/drivers/base/dma-contiguous.c
+++ b/drivers/base/dma-contiguous.c
@@ -96,7 +96,7 @@ static inline __maybe_unused phys_addr_t cma_early_percent_memory(void)
#endif
/**
- * dma_contiguous_reserve() - reserve area for contiguous memory handling
+ * dma_contiguous_reserve() - reserve area(s) for contiguous memory handling
* @limit: End address of the reserved memory (optional, 0 for any).
*
* This function reserves memory from early allocator. It should be
@@ -124,22 +124,29 @@ void __init dma_contiguous_reserve(phys_addr_t limit)
#endif
}
- if (selected_size) {
+ if (selected_size && !dma_contiguous_default_area) {
pr_debug("%s: reserving %ld MiB for global area\n", __func__,
(unsigned long)selected_size / SZ_1M);
- dma_declare_contiguous(NULL, selected_size, 0, limit);
+ dma_contiguous_reserve_area(selected_size, 0, limit,
+ &dma_contiguous_default_area);
}
};
static DEFINE_MUTEX(cma_mutex);
-static int __init cma_activate_area(unsigned long base_pfn, unsigned long count)
+static int __init cma_activate_area(struct cma *cma)
{
- unsigned long pfn = base_pfn;
- unsigned i = count >> pageblock_order;
+ int bitmap_size = BITS_TO_LONGS(cma->count) * sizeof(long);
+ unsigned long base_pfn = cma->base_pfn, pfn = base_pfn;
+ unsigned i = cma->count >> pageblock_order;
struct zone *zone;
+ cma->bitmap = kzalloc(bitmap_size, GFP_KERNEL);
+
+ if (!cma->bitmap)
+ return -ENOMEM;
+
WARN_ON_ONCE(!pfn_valid(pfn));
zone = page_zone(pfn_to_page(pfn));
@@ -153,92 +160,53 @@ static int __init cma_activate_area(unsigned long base_pfn, unsigned long count)
}
init_cma_reserved_pageblock(pfn_to_page(base_pfn));
} while (--i);
- return 0;
-}
-
-static struct cma * __init cma_create_area(unsigned long base_pfn,
- unsigned long count)
-{
- int bitmap_size = BITS_TO_LONGS(count) * sizeof(long);
- struct cma *cma;
- int ret = -ENOMEM;
-
- pr_debug("%s(base %08lx, count %lx)\n", __func__, base_pfn, count);
-
- cma = kmalloc(sizeof *cma, GFP_KERNEL);
- if (!cma)
- return ERR_PTR(-ENOMEM);
-
- cma->base_pfn = base_pfn;
- cma->count = count;
- cma->bitmap = kzalloc(bitmap_size, GFP_KERNEL);
- if (!cma->bitmap)
- goto no_mem;
-
- ret = cma_activate_area(base_pfn, count);
- if (ret)
- goto error;
-
- pr_debug("%s: returned %p\n", __func__, (void *)cma);
- return cma;
-
-error:
- kfree(cma->bitmap);
-no_mem:
- kfree(cma);
- return ERR_PTR(ret);
+ return 0;
}
-static struct cma_reserved {
- phys_addr_t start;
- unsigned long size;
- struct device *dev;
-} cma_reserved[MAX_CMA_AREAS] __initdata;
-static unsigned cma_reserved_count __initdata;
+static struct cma cma_areas[MAX_CMA_AREAS];
+static unsigned cma_area_count;
static int __init cma_init_reserved_areas(void)
{
- struct cma_reserved *r = cma_reserved;
- unsigned i = cma_reserved_count;
-
- pr_debug("%s()\n", __func__);
+ int i;
- for (; i; --i, ++r) {
- struct cma *cma;
- cma = cma_create_area(PFN_DOWN(r->start),
- r->size >> PAGE_SHIFT);
- if (!IS_ERR(cma))
- dev_set_cma_area(r->dev, cma);
+ for (i = 0; i < cma_area_count; i++) {
+ int ret = cma_activate_area(&cma_areas[i]);
+ if (ret)
+ return ret;
}
+
return 0;
}
core_initcall(cma_init_reserved_areas);
/**
- * dma_declare_contiguous() - reserve area for contiguous memory handling
- * for particular device
- * @dev: Pointer to device structure.
- * @size: Size of the reserved memory.
- * @base: Start address of the reserved memory (optional, 0 for any).
+ * dma_contiguous_reserve_area() - reserve custom contiguous area
+ * @size: Size of the reserved area (in bytes),
+ * @base: Base address of the reserved area optional, use 0 for any
* @limit: End address of the reserved memory (optional, 0 for any).
+ * @res_cma: Pointer to store the created cma region.
*
- * This function reserves memory for specified device. It should be
- * called by board specific code when early allocator (memblock or bootmem)
- * is still activate.
+ * This function reserves memory from early allocator. It should be
+ * called by arch specific code once the early allocator (memblock or bootmem)
+ * has been activated and all other subsystems have already allocated/reserved
+ * memory. This function allows to create custom reserved areas for specific
+ * devices.
*/
-int __init dma_declare_contiguous(struct device *dev, phys_addr_t size,
- phys_addr_t base, phys_addr_t limit)
+int __init dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base,
+ phys_addr_t limit, struct cma **res_cma)
{
- struct cma_reserved *r = &cma_reserved[cma_reserved_count];
+ struct cma *cma = &cma_areas[cma_area_count];
phys_addr_t alignment;
+ int ret = 0;
pr_debug("%s(size %lx, base %08lx, limit %08lx)\n", __func__,
(unsigned long)size, (unsigned long)base,
(unsigned long)limit);
/* Sanity checks */
- if (cma_reserved_count == ARRAY_SIZE(cma_reserved)) {
+ if (cma_area_count == ARRAY_SIZE(cma_areas)) {
pr_err("Not enough slots for CMA reserved regions!\n");
return -ENOSPC;
}
@@ -256,7 +224,7 @@ int __init dma_declare_contiguous(struct device *dev, phys_addr_t size,
if (base) {
if (memblock_is_region_reserved(base, size) ||
memblock_reserve(base, size) < 0) {
- base = -EBUSY;
+ ret = -EBUSY;
goto err;
}
} else {
@@ -266,7 +234,7 @@ int __init dma_declare_contiguous(struct device *dev, phys_addr_t size,
*/
phys_addr_t addr = __memblock_alloc_base(size, alignment, limit);
if (!addr) {
- base = -ENOMEM;
+ ret = -ENOMEM;
goto err;
} else {
base = addr;
@@ -277,10 +245,11 @@ int __init dma_declare_contiguous(struct device *dev, phys_addr_t size,
* Each reserved area must be initialised later, when more kernel
* subsystems (like slab allocator) are available.
*/
- r->start = base;
- r->size = size;
- r->dev = dev;
- cma_reserved_count++;
+ cma->base_pfn = PFN_DOWN(base);
+ cma->count = size >> PAGE_SHIFT;
+ *res_cma = cma;
+ cma_area_count++;
+
pr_info("CMA: reserved %ld MiB at %08lx\n", (unsigned long)size / SZ_1M,
(unsigned long)base);
@@ -289,7 +258,7 @@ int __init dma_declare_contiguous(struct device *dev, phys_addr_t size,
return 0;
err:
pr_err("CMA: failed to reserve %ld MiB\n", (unsigned long)size / SZ_1M);
- return base;
+ return ret;
}
/**
diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig
index 78cc760..9d2009a 100644
--- a/drivers/of/Kconfig
+++ b/drivers/of/Kconfig
@@ -74,4 +74,10 @@ config OF_MTD
depends on MTD
def_bool y
+config OF_RESERVED_MEM
+ depends on OF_FLATTREE && (DMA_CMA || (HAVE_GENERIC_DMA_COHERENT && HAVE_MEMBLOCK))
+ def_bool y
+ help
+ Initialization code for DMA reserved memory
+
endmenu # OF
diff --git a/drivers/of/Makefile b/drivers/of/Makefile
index efd0510..ed9660a 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 b10ba00..4fb06f3 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -545,6 +545,82 @@ int __init of_flat_dt_match(unsigned long node, const char *const *compat)
return of_fdt_match(initial_boot_params, node, compat);
}
+struct fdt_scan_status {
+ const char *name;
+ int namelen;
+ int depth;
+ int found;
+ int (*iterator)(unsigned long node, const char *uname, int depth, void *data);
+ void *data;
+};
+
+/**
+ * fdt_scan_node_by_path - iterator for of_scan_flat_dt_by_path function
+ */
+static int __init fdt_scan_node_by_path(unsigned long node, const char *uname,
+ int depth, void *data)
+{
+ struct fdt_scan_status *st = data;
+
+ /*
+ * if scan at the requested fdt node has been completed,
+ * return -ENXIO to abort further scanning
+ */
+ if (depth <= st->depth)
+ return -ENXIO;
+
+ /* requested fdt node has been found, so call iterator function */
+ if (st->found)
+ return st->iterator(node, uname, depth, st->data);
+
+ /* check if scanning automata is entering next level of fdt nodes */
+ if (depth == st->depth + 1 &&
+ strncmp(st->name, uname, st->namelen) == 0 &&
+ uname[st->namelen] == 0) {
+ st->depth += 1;
+ if (st->name[st->namelen] == 0) {
+ st->found = 1;
+ } else {
+ const char *next = st->name + st->namelen + 1;
+ st->name = next;
+ st->namelen = strcspn(next, "/");
+ }
+ return 0;
+ }
+
+ /* scan next fdt node */
+ return 0;
+}
+
+/**
+ * of_scan_flat_dt_by_path - scan flattened tree blob and call callback on each
+ * child of the given path.
+ * @path: path to start searching for children
+ * @it: callback function
+ * @data: context data pointer
+ *
+ * This function is used to scan the flattened device-tree starting from the
+ * node given by path. It is used to extract information (like reserved
+ * memory), which is required on ealy boot before we can unflatten the tree.
+ */
+int __init of_scan_flat_dt_by_path(const char *path,
+ int (*it)(unsigned long node, const char *name, int depth, void *data),
+ void *data)
+{
+ struct fdt_scan_status st = {path, 0, -1, 0, it, data};
+ int ret = 0;
+
+ if (initial_boot_params)
+ ret = of_scan_flat_dt(fdt_scan_node_by_path, &st);
+
+ if (!st.found)
+ return -ENOENT;
+ else if (ret == -ENXIO) /* scan has been completed */
+ return 0;
+ else
+ return ret;
+}
+
#ifdef CONFIG_BLK_DEV_INITRD
/**
* early_init_dt_check_for_initrd - Decode initrd location from flat tree
diff --git a/drivers/of/of_reserved_mem.c b/drivers/of/of_reserved_mem.c
new file mode 100644
index 0000000..a754b84
--- /dev/null
+++ b/drivers/of/of_reserved_mem.c
@@ -0,0 +1,175 @@
+/*
+ * Device tree based initialization code for reserved memory.
+ *
+ * Copyright (c) 2013 Samsung Electronics Co., Ltd.
+ * http://www.samsung.com
+ * Author: Marek Szyprowski <m.szyprowski@samsung.com>
+ *
+ * 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 <asm/dma-contiguous.h>
+
+#include <linux/memblock.h>
+#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/mm_types.h>
+#include <linux/dma-contiguous.h>
+#include <linux/dma-mapping.h>
+#include <linux/of_reserved_mem.h>
+
+#define MAX_RESERVED_REGIONS 16
+struct reserved_mem {
+ phys_addr_t base;
+ unsigned long size;
+ struct cma *cma;
+ char name[32];
+};
+static struct reserved_mem reserved_mem[MAX_RESERVED_REGIONS];
+static int reserved_mem_count;
+
+static int __init fdt_scan_reserved_mem(unsigned long node, const char *uname,
+ int depth, void *data)
+{
+ struct reserved_mem *rmem = &reserved_mem[reserved_mem_count];
+ phys_addr_t base, size;
+ int is_cma, is_reserved;
+ unsigned long len;
+ const char *status;
+ __be32 *prop;
+
+ is_cma = IS_ENABLED(CONFIG_DMA_CMA) &&
+ of_flat_dt_is_compatible(node, "linux,contiguous-memory-region");
+ is_reserved = of_flat_dt_is_compatible(node, "reserved-memory-region");
+
+ if (!is_reserved && !is_cma) {
+ /* ignore node and scan next one */
+ return 0;
+ }
+
+ status = of_get_flat_dt_prop(node, "status", &len);
+ if (status && strcmp(status, "okay") != 0) {
+ /* ignore disabled node nad scan next one */
+ return 0;
+ }
+
+ prop = of_get_flat_dt_prop(node, "reg", &len);
+ if (!prop || (len < (dt_root_size_cells + dt_root_addr_cells) *
+ sizeof(__be32))) {
+ pr_err("Reserved mem: node %s, incorrect \"reg\" property\n",
+ uname);
+ /* ignore node and scan next one */
+ return 0;
+ }
+ base = dt_mem_next_cell(dt_root_addr_cells, &prop);
+ size = dt_mem_next_cell(dt_root_size_cells, &prop);
+
+ if (!size) {
+ /* ignore node and scan next one */
+ return 0;
+ }
+
+ pr_info("Reserved mem: found %s, memory base %lx, size %ld MiB\n",
+ uname, (unsigned long)base, (unsigned long)size / SZ_1M);
+
+ if (reserved_mem_count == ARRAY_SIZE(reserved_mem))
+ return -ENOSPC;
+
+ rmem->base = base;
+ rmem->size = size;
+ strlcpy(rmem->name, uname, sizeof(rmem->name));
+
+ if (is_cma) {
+ struct cma *cma;
+ if (dma_contiguous_reserve_area(size, base, 0, &cma) == 0) {
+ rmem->cma = cma;
+ reserved_mem_count++;
+ if (of_get_flat_dt_prop(node,
+ "linux,default-contiguous-region",
+ NULL))
+ dma_contiguous_set_default(cma);
+ }
+ } else if (is_reserved) {
+ if (memblock_remove(base, size) == 0)
+ reserved_mem_count++;
+ else
+ pr_err("Failed to reserve memory for %s\n", uname);
+ }
+
+ return 0;
+}
+
+static struct reserved_mem *get_dma_memory_region(struct device *dev)
+{
+ struct device_node *node;
+ const char *name;
+ int i;
+
+ node = of_parse_phandle(dev->of_node, "memory-region", 0);
+ if (!node)
+ return NULL;
+
+ name = kbasename(node->full_name);
+ for (i = 0; i < reserved_mem_count; i++)
+ if (strcmp(name, reserved_mem[i].name) == 0)
+ 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.
+ */
+void of_reserved_mem_device_init(struct device *dev)
+{
+ struct reserved_mem *region = get_dma_memory_region(dev);
+ if (!region)
+ return;
+
+ if (region->cma) {
+ dev_set_cma_area(dev, region->cma);
+ pr_info("Assigned CMA %s to %s device\n", region->name,
+ dev_name(dev));
+ } else {
+ if (dma_declare_coherent_memory(dev, region->base, region->base,
+ region->size, DMA_MEMORY_MAP | DMA_MEMORY_EXCLUSIVE) != 0)
+ pr_info("Declared reserved memory %s to %s device\n",
+ region->name, dev_name(dev));
+ }
+}
+
+/**
+ * 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 *region = get_dma_memory_region(dev);
+ if (!region && !region->cma)
+ dma_release_declared_memory(dev);
+}
+
+/**
+ * early_init_dt_scan_reserved_mem() - create reserved memory regions
+ *
+ * This function grabs memory from early allocator for device exclusive use
+ * defined in device tree structures. It should be called by arch specific code
+ * once the early allocator (memblock) has been activated and all other
+ * subsystems have already allocated/reserved memory.
+ */
+void __init early_init_dt_scan_reserved_mem(void)
+{
+ of_scan_flat_dt_by_path("/memory/reserved-memory",
+ fdt_scan_reserved_mem, NULL);
+}
diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index e0a6514..eeca8a5 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -21,6 +21,7 @@
#include <linux/of_device.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
+#include <linux/of_reserved_mem.h>
#include <linux/platform_device.h>
const struct of_device_id of_default_bus_match_table[] = {
@@ -218,6 +219,8 @@ struct platform_device *of_platform_device_create_pdata(
dev->dev.bus = &platform_bus_type;
dev->dev.platform_data = platform_data;
+ of_reserved_mem_device_init(&dev->dev);
+
/* We do not fill the DMA ops for platform devices by default.
* This is currently the responsibility of the platform code
* to do such, possibly using a device notifier
@@ -225,6 +228,7 @@ struct platform_device *of_platform_device_create_pdata(
if (of_device_add(dev) != 0) {
platform_device_put(dev);
+ of_reserved_mem_device_release(&dev->dev);
return NULL;
}
diff --git a/include/asm-generic/dma-contiguous.h b/include/asm-generic/dma-contiguous.h
deleted file mode 100644
index 294b1e7..0000000
--- a/include/asm-generic/dma-contiguous.h
+++ /dev/null
@@ -1,28 +0,0 @@
-#ifndef ASM_DMA_CONTIGUOUS_H
-#define ASM_DMA_CONTIGUOUS_H
-
-#ifdef __KERNEL__
-#ifdef CONFIG_CMA
-
-#include <linux/device.h>
-#include <linux/dma-contiguous.h>
-
-static inline struct cma *dev_get_cma_area(struct device *dev)
-{
- if (dev && dev->cma_area)
- return dev->cma_area;
- return dma_contiguous_default_area;
-}
-
-static inline void dev_set_cma_area(struct device *dev, struct cma *cma)
-{
- if (dev)
- dev->cma_area = cma;
- if (!dev && !dma_contiguous_default_area)
- dma_contiguous_default_area = cma;
-}
-
-#endif
-#endif
-
-#endif
diff --git a/include/linux/device.h b/include/linux/device.h
index f46646e..2a9d6ed 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -737,7 +737,7 @@ struct device {
struct dma_coherent_mem *dma_mem; /* internal for coherent mem
override */
-#ifdef CONFIG_CMA
+#ifdef CONFIG_DMA_CMA
struct cma *cma_area; /* contiguous memory area for dma
allocations */
#endif
diff --git a/include/linux/dma-contiguous.h b/include/linux/dma-contiguous.h
index 00141d3..3b28f93 100644
--- a/include/linux/dma-contiguous.h
+++ b/include/linux/dma-contiguous.h
@@ -67,9 +67,53 @@ struct device;
extern struct cma *dma_contiguous_default_area;
+static inline struct cma *dev_get_cma_area(struct device *dev)
+{
+ if (dev && dev->cma_area)
+ return dev->cma_area;
+ return dma_contiguous_default_area;
+}
+
+static inline void dev_set_cma_area(struct device *dev, struct cma *cma)
+{
+ if (dev)
+ dev->cma_area = cma;
+}
+
+static inline void dma_contiguous_set_default(struct cma *cma)
+{
+ dma_contiguous_default_area = cma;
+}
+
void dma_contiguous_reserve(phys_addr_t addr_limit);
-int dma_declare_contiguous(struct device *dev, phys_addr_t size,
- phys_addr_t base, phys_addr_t limit);
+
+int __init dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base,
+ phys_addr_t limit, struct cma **res_cma);
+
+/**
+ * dma_declare_contiguous() - reserve area for contiguous memory handling
+ * for particular device
+ * @dev: Pointer to device structure.
+ * @size: Size of the reserved memory.
+ * @base: Start address of the reserved memory (optional, 0 for any).
+ * @limit: End address of the reserved memory (optional, 0 for any).
+ *
+ * This function reserves memory for specified device. It should be
+ * called by board specific code when early allocator (memblock or bootmem)
+ * is still activate.
+ */
+
+static inline int dma_declare_contiguous(struct device *dev, phys_addr_t size,
+ phys_addr_t base, phys_addr_t limit)
+{
+ struct cma *cma;
+ int ret;
+ ret = dma_contiguous_reserve_area(size, base, limit, &cma);
+ if (ret == 0)
+ dev_set_cma_area(dev, cma);
+
+ return ret;
+}
struct page *dma_alloc_from_contiguous(struct device *dev, int count,
unsigned int order);
@@ -80,8 +124,22 @@ bool dma_release_from_contiguous(struct device *dev, struct page *pages,
#define MAX_CMA_AREAS (0)
+static inline struct cma *dev_get_cma_area(struct device *dev)
+{
+ return NULL;
+}
+
+static inline void dev_set_cma_area(struct device *dev, struct cma *cma) { }
+
+static inline void dma_contiguous_set_default(struct cma *cma) { }
+
static inline void dma_contiguous_reserve(phys_addr_t limit) { }
+static inline int dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base,
+ phys_addr_t limit, struct cma **res_cma) {
+ return -ENOSYS;
+}
+
static inline
int dma_declare_contiguous(struct device *dev, phys_addr_t size,
phys_addr_t base, phys_addr_t limit)
diff --git a/include/linux/of_fdt.h b/include/linux/of_fdt.h
index ed136ad..19f26f8 100644
--- a/include/linux/of_fdt.h
+++ b/include/linux/of_fdt.h
@@ -90,6 +90,9 @@ extern void *of_get_flat_dt_prop(unsigned long node, const char *name,
extern int of_flat_dt_is_compatible(unsigned long node, const char *name);
extern int of_flat_dt_match(unsigned long node, const char *const *matches);
extern unsigned long of_get_flat_dt_root(void);
+extern int of_scan_flat_dt_by_path(const char *path,
+ int (*it)(unsigned long node, const char *name, int depth, void *data),
+ void *data);
extern int early_init_dt_scan_chosen(unsigned long node, const char *uname,
int depth, void *data);
diff --git a/include/linux/of_reserved_mem.h b/include/linux/of_reserved_mem.h
new file mode 100644
index 0000000..c841282
--- /dev/null
+++ b/include/linux/of_reserved_mem.h
@@ -0,0 +1,14 @@
+#ifndef __OF_RESERVED_MEM_H
+#define __OF_RESERVED_MEM_H
+
+#ifdef CONFIG_OF_RESERVED_MEM
+void of_reserved_mem_device_init(struct device *dev);
+void of_reserved_mem_device_release(struct device *dev);
+void early_init_dt_scan_reserved_mem(void);
+#else
+static inline void of_reserved_mem_device_init(struct device *dev) { }
+static inline void of_reserved_mem_device_release(struct device *dev) { }
+static inline void early_init_dt_scan_reserved_mem(void) { }
+#endif
+
+#endif /* __OF_RESERVED_MEM_H */
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