From: Grant Likely grant.likely@linaro.org

Reserved memory nodes allow for the reservation of static (fixed address) regions, or dynamically allocated regions for a specific purpose.

Signed-off-by: Grant Likely grant.likely@linaro.org [joshc: Based on binding document proposed (in non-patch form) here: http://lkml.kernel.org/g/20131030134702.19B57C402A0@trevor.secretlab.ca adapted to support #memory-region-cells] Signed-off-by: Josh Cartwright joshc@codeaurora.org [mszyprow: removed #memory-region-cells property] Signed-off-by: Marek Szyprowski m.szyprowski@samsung.com --- .../bindings/reserved-memory/reserved-memory.txt | 136 ++++++++++++++++++++ 1 file changed, 136 insertions(+) create mode 100644 Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt

diff --git a/Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt b/Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt new file mode 100644 index 000000000000..8b0d747a38e7 --- /dev/null +++ b/Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt @@ -0,0 +1,136 @@ +*** Reserved memory regions *** + +Reserved memory is specified as a node under the /reserved-memory node. +The operating system shall exclude reserved memory from normal usage +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. + +Parameters for each memory region can be encoded into the device tree +with the following nodes: + +/reserved-memory node +--------------------- +#address-cells, #size-cells (required) - standard definition + - Should use the same values as the root node +ranges (required) - standard definition + - Should be empty + +/reserved-memory/ child nodes +----------------------------- +Each child of the reserved-memory node specifies one or more regions of +reserved memory. Each child node may either use a 'reg' property to +specify a specific range of reserved memory, or a 'size' property with +optional constraints to request a dynamically allocated block of memory. + +Following the generic-names recommended practice, node names should +reflect the purpose of the node (ie. "framebuffer" or "dma-pool"). Unit +address (@<address>) should be appended to the name if the node is a +static allocation. + +Properties: +Requires either a) or b) below. +a) static allocation + reg (required) - standard definition +b) dynamic allocation + size (required) - length based on parent's #size-cells + - Size in bytes of memory to reserve. + alignment (optional) - length based on parent's #size-cells + - Address boundary for alignment of allocation. + alloc-ranges (optional) - prop-encoded-array (address, length pairs). + - Specifies regions of memory that are + acceptable to allocate from. + +If both reg and size are present, then the reg property takes precedence +and size is ignored. + +Additional properties: +compatible (optional) - standard definition + - may contain the following strings: + - shared-dma-pool: This indicates a region of memory meant to be + used as a shared pool of DMA buffers for a set of devices. It can + be used by an operating system to instanciate the necessary pool + management subsystem if necessary. + - vendor specific string in the form <vendor>,[<device>-]<usage> +no-map (optional) - empty property + - Indicates the operating system must not create a virtual mapping + of the region as part of its standard mapping of system memory, + nor permit speculative access to it under any circumstances other + than under the control of the device driver using the region. +reusable (optional) - empty property + - The operating system can use the memory in this region with the + limitation that the device driver(s) owning the region need to be + able to reclaim it back. Typically that means that the operating + system can use that region to store volatile or cached data that + can be otherwise regenerated or migrated elsewhere. + +Linux implementation note: +- If a "linux,cma-default" property is present, then Linux will use the + region for the default pool of the contiguous memory allocator. + +Device node references to reserved memory +----------------------------------------- +Regions in the /reserved-memory node may be referenced by other device +nodes by adding a memory-region property to the device node. + +memory-region (optional) - phandle, specifier pairs to children of /reserved-memory + +Example +------- +This example defines 3 contiguous regions are defined for Linux kernel: +one default of all device drivers (named linux,cma@72000000 and 64MiB in size), +one dedicated to the framebuffer device (named framebuffer@78000000, 8MiB), and +one for multimedia processing (named multimedia-memory@77000000, 64MiB). + +/ { + #address-cells = <1>; + #size-cells = <1>; + + memory { + reg = <0x40000000 0x40000000>; + }; + + reserved-memory { + #address-cells = <1>; + #size-cells = <1>; + ranges; + + /* global autoconfigured region for contiguous allocations */ + linux,cma { + compatible = "shared-dma-pool"; + reusable; + #memory-region-cells = <0>; + size = <0x4000000>; + alignment = <0x2000>; + linux,cma-default; + }; + + display_reserved: framebuffer@78000000 { + #memory-region-cells = <0>; + reg = <0x78000000 0x800000>; + }; + + multimedia_reserved: multimedia@77000000 { + compatible = "acme,multimedia-memory"; + #memory-region-cells = <1>; + reg = <0x77000000 0x4000000>; + }; + }; + + /* ... */ + + fb0: video@12300000 { + memory-region = <&display_reserved>; + /* ... */ + }; + + scaler: scaler@12500000 { + memory-region = <&multimedia_reserved 0xdeadbeef>; + /* ... */ + }; + + codec: codec@12600000 { + memory-region = <&multimedia_reserved 0xfeebdaed>; + /* ... */ + }; +};

This patch adds support for static (defined by 'reg' property) reserved memory regions declared in device tree.

Memory blocks can be reliably reserved only during early boot. This must happen before the whole memory management subsystem is initialized, because we need to ensure that the given contiguous blocks are not yet allocated by kernel. Also it must happen before kernel mappings for the whole low memory are created, to ensure that there will be no mappings (for reserved blocks). Typically, all this happens before device tree structures are unflattened, so we need to get reserved memory layout directly from fdt.

Based on previous code provided by Josh Cartwright joshc@codeaurora.org

Signed-off-by: Marek Szyprowski m.szyprowski@samsung.com Acked-by: Grant Likely grant.likely@linaro.org --- drivers/of/fdt.c | 131 ++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/of_fdt.h | 3 ++ 2 files changed, 134 insertions(+)

diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c index 758b4f8b30b7..819e11209718 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/sizes.h> #include <linux/string.h> #include <linux/errno.h> #include <linux/slab.h> @@ -440,6 +441,118 @@ struct boot_param_header *initial_boot_params; #ifdef CONFIG_OF_EARLY_FLATTREE

/** + * res_mem_reserve_reg() - reserve all memory described in 'reg' property + */ +static int __init __reserved_mem_reserve_reg(unsigned long node, + const char *uname) +{ + int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32); + phys_addr_t base, size; + unsigned long len; + __be32 *prop; + int nomap; + + prop = of_get_flat_dt_prop(node, "reg", &len); + if (!prop) + return -ENOENT; + + if (len && len % t_len != 0) { + pr_err("Reserved memory: invalid reg property in '%s', skipping node.\n", + uname); + return -EINVAL; + } + + nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL; + + while (len >= t_len) { + base = dt_mem_next_cell(dt_root_addr_cells, &prop); + size = dt_mem_next_cell(dt_root_size_cells, &prop); + + if (base && size && + early_init_dt_reserve_memory_arch(base, size, nomap) == 0) + pr_debug("Reserved memory: reserved region for node '%s': base %pa, size %ld MiB\n", + uname, &base, (unsigned long)size / SZ_1M); + else + pr_info("Reserved memory: failed to reserve memory for node '%s': base %pa, size %ld MiB\n", + uname, &base, (unsigned long)size / SZ_1M); + + len -= t_len; + } + return 0; +} + +/** + * __reserved_mem_check_root() - check if #size-cells, #address-cells provided + * in /reserved-memory matches the values supported by the current implementation, + * also check if ranges property has been provided + */ +static int __reserved_mem_check_root(unsigned long node) +{ + __be32 *prop; + + prop = of_get_flat_dt_prop(node, "#size-cells", NULL); + if (!prop || be32_to_cpup(prop) != dt_root_size_cells) + return -EINVAL; + + prop = of_get_flat_dt_prop(node, "#address-cells", NULL); + if (!prop || be32_to_cpup(prop) != dt_root_addr_cells) + return -EINVAL; + + prop = of_get_flat_dt_prop(node, "ranges", NULL); + if (!prop) + return -EINVAL; + return 0; +} + +/** + * fdt_scan_reserved_mem() - scan a single FDT node for reserved memory + */ +static int __init __fdt_scan_reserved_mem(unsigned long node, const char *uname, + int depth, void *data) +{ + static int found; + const char *status; + + if (!found && depth == 1 && strcmp(uname, "reserved-memory") == 0) { + if (__reserved_mem_check_root(node) != 0) { + pr_err("Reserved memory: unsupported node format, ignoring\n"); + /* break scan */ + return 1; + } + found = 1; + /* scan next node */ + return 0; + } else if (!found) { + /* scan next node */ + return 0; + } else if (found && depth < 2) { + /* scanning of /reserved-memory has been finished */ + return 1; + } + + status = of_get_flat_dt_prop(node, "status", NULL); + if (status && strcmp(status, "okay") != 0 && strcmp(status, "ok") != 0) + return 0; + + __reserved_mem_reserve_reg(node, uname); + + /* scan next node */ + return 0; +} + +/** + * early_init_fdt_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 (i.e. memblock) has been fully activated. + */ +void __init early_init_fdt_scan_reserved_mem(void) +{ + of_scan_flat_dt(__fdt_scan_reserved_mem, NULL); +} + +/** * of_scan_flat_dt - scan flattened tree blob and call callback on each. * @it: callback function * @data: context data pointer @@ -856,6 +969,16 @@ void __init __weak early_init_dt_add_memory_arch(u64 base, u64 size) memblock_add(base, size); }

+int __init __weak early_init_dt_reserve_memory_arch(phys_addr_t base, + phys_addr_t size, bool nomap) +{ + if (memblock_is_region_reserved(base, size)) + return -EBUSY; + if (nomap) + return memblock_remove(base, size); + return memblock_reserve(base, size); +} + /* * called from unflatten_device_tree() to bootstrap devicetree itself * Architectures can override this definition if memblock isn't used @@ -864,6 +987,14 @@ void * __init __weak early_init_dt_alloc_memory_arch(u64 size, u64 align) { return __va(memblock_alloc(size, align)); } +#else +int __init __weak early_init_dt_reserve_memory_arch(phys_addr_t base, + phys_addr_t size, bool nomap) +{ + pr_err("Reserved memory not supported, ignoring range 0x%llx - 0x%llx%s\n", + base, size, nomap ? " (nomap)" : ""); + return -ENOSYS; +} #endif

bool __init early_init_dt_scan(void *params) diff --git a/include/linux/of_fdt.h b/include/linux/of_fdt.h index 2b77058a7335..8610ad8d77d2 100644 --- a/include/linux/of_fdt.h +++ b/include/linux/of_fdt.h @@ -98,7 +98,10 @@ extern int early_init_dt_scan_chosen(unsigned long node, const char *uname, int depth, void *data); extern int early_init_dt_scan_memory(unsigned long node, const char *uname, int depth, void *data); +extern void early_init_fdt_scan_reserved_mem(void); extern void early_init_dt_add_memory_arch(u64 base, u64 size); +extern int early_init_dt_reserve_memory_arch(phys_addr_t base, phys_addr_t size, + bool no_map); extern void * early_init_dt_alloc_memory_arch(u64 size, u64 align); extern u64 dt_mem_next_cell(int s, __be32 **cellp);

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@codeaurora.org

Signed-off-by: Marek Szyprowski m.szyprowski@samsung.com Acked-by: Grant Likely grant.likely@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 819e11209718..510c0d8de8a0 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/sizes.h> #include <linux/string.h> #include <linux/errno.h> @@ -450,7 +451,7 @@ 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) @@ -477,6 +478,10 @@ 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; } @@ -512,6 +517,7 @@ 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) { @@ -534,7 +540,9 @@ 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; @@ -550,6 +558,7 @@ 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..69b811779585 --- /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@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; + 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 */

Add support for custom reserved memory drivers. Call their init() function for each reserved region and prepare for using operations provided by them with by the reserved_mem->ops array.

Based on previous code provided by Josh Cartwright joshc@codeaurora.org

Signed-off-by: Marek Szyprowski m.szyprowski@samsung.com --- drivers/of/of_reserved_mem.c | 29 +++++++++++++++++++++++++++++ include/asm-generic/vmlinux.lds.h | 11 +++++++++++ include/linux/of_reserved_mem.h | 32 ++++++++++++++++++++++++++++++++ 3 files changed, 72 insertions(+)

diff --git a/drivers/of/of_reserved_mem.c b/drivers/of/of_reserved_mem.c index 69b811779585..daaaf935911d 100644 --- a/drivers/of/of_reserved_mem.c +++ b/drivers/of/of_reserved_mem.c @@ -170,6 +170,33 @@ static int __init __reserved_mem_alloc_size(unsigned long node, 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, rmem->fdt_node, rmem->name) == 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 */ @@ -184,5 +211,7 @@ void __init fdt_init_reserved_mem(void) if (rmem->size == 0) err = __reserved_mem_alloc_size(node, rmem->name, &rmem->base, &rmem->size); + if (err == 0) + __reserved_mem_init_node(rmem); } } diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index bc2121fa9132..f10f64fcc815 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -167,6 +167,16 @@ #define CLK_OF_TABLES() #endif

+#ifdef CONFIG_OF_RESERVED_MEM +#define RESERVEDMEM_OF_TABLES() \ + . = ALIGN(8); \ + VMLINUX_SYMBOL(__reservedmem_of_table) = .; \ + *(__reservedmem_of_table) \ + *(__reservedmem_of_table_end) +#else +#define RESERVEDMEM_OF_TABLES() +#endif + #define KERNEL_DTB() \ STRUCT_ALIGN(); \ VMLINUX_SYMBOL(__dtb_start) = .; \ @@ -490,6 +500,7 @@ TRACE_SYSCALLS() \ MEM_DISCARD(init.rodata) \ CLK_OF_TABLES() \ + RESERVEDMEM_OF_TABLES() \ CLKSRC_OF_TABLES() \ KERNEL_DTB() \ IRQCHIP_OF_MATCH_TABLE() diff --git a/include/linux/of_reserved_mem.h b/include/linux/of_reserved_mem.h index 89226ed7d954..9b1fbb7f29fc 100644 --- a/include/linux/of_reserved_mem.h +++ b/include/linux/of_reserved_mem.h @@ -1,21 +1,53 @@ #ifndef __OF_RESERVED_MEM_H #define __OF_RESERVED_MEM_H

+struct device; +struct of_phandle_args; +struct reserved_mem_ops; + struct reserved_mem { const char *name; unsigned long fdt_node; + const struct reserved_mem_ops *ops; phys_addr_t base; phys_addr_t size; + void *priv; +}; + +struct reserved_mem_ops { + void (*device_init)(struct reserved_mem *rmem, + struct device *dev); + void (*device_release)(struct reserved_mem *rmem, + struct device *dev); };

+typedef int (*reservedmem_of_init_fn)(struct reserved_mem *rmem, + unsigned long node, const char *uname); + #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); + +#define RESERVEDMEM_OF_DECLARE(name, compat, init) \ + static const struct of_device_id __reservedmem_of_table_##name \ + __used __section(__reservedmem_of_table) \ + = { .compatible = compat, \ + .data = (init == (reservedmem_of_init_fn)NULL) ? \ + init : init } + #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) { } + +#define RESERVEDMEM_OF_DECLARE(name, compat, init) \ + static const struct of_device_id __reservedmem_of_table_##name \ + __attribute__((unused)) \ + = { .compatible = compat, \ + .data = (init == (reservedmem_of_init_fn)NULL) ? \ + init : init } + #endif

#endif /* __OF_RESERVED_MEM_H */

This patch adds code for automated assignment of reserved memory regions to struct device. reserved_mem->ops->device_init()/device_cleanup() callbacks are called to perform reserved memory driver specific initialization and cleanup

Based on previous code provided by Josh Cartwright joshc@codeaurora.org

Signed-off-by: Marek Szyprowski m.szyprowski@samsung.com --- drivers/of/of_reserved_mem.c | 70 +++++++++++++++++++++++++++++++++++++++ include/linux/of_reserved_mem.h | 7 ++++ 2 files changed, 77 insertions(+)

diff --git a/drivers/of/of_reserved_mem.c b/drivers/of/of_reserved_mem.c index daaaf935911d..5c45016efd31 100644 --- a/drivers/of/of_reserved_mem.c +++ b/drivers/of/of_reserved_mem.c @@ -206,8 +206,16 @@ void __init fdt_init_reserved_mem(void) for (i = 0; i < reserved_mem_count; i++) { struct reserved_mem *rmem = &reserved_mem[i]; unsigned long node = rmem->fdt_node; + unsigned long len; + __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); @@ -215,3 +223,65 @@ void __init fdt_init_reserved_mem(void) __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. + */ +void of_reserved_mem_device_init(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_init) + return; + + rmem->ops->device_init(rmem, dev); + dev_info(dev, "assigned reserved memory node %s\n", rmem->name); +} + +/** + * 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); +} diff --git a/include/linux/of_reserved_mem.h b/include/linux/of_reserved_mem.h index 9b1fbb7f29fc..6a54e6565b89 100644 --- a/include/linux/of_reserved_mem.h +++ b/include/linux/of_reserved_mem.h @@ -8,6 +8,7 @@ struct reserved_mem_ops; struct reserved_mem { const char *name; unsigned long fdt_node; + unsigned long phandle; const struct reserved_mem_ops *ops; phys_addr_t base; phys_addr_t size; @@ -25,6 +26,9 @@ typedef int (*reservedmem_of_init_fn)(struct reserved_mem *rmem, unsigned long node, const char *uname);

#ifdef CONFIG_OF_RESERVED_MEM +void of_reserved_mem_device_init(struct device *dev); +void of_reserved_mem_device_release(struct device *dev); + 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); @@ -37,6 +41,9 @@ void fdt_reserved_mem_save_node(unsigned long node, const char *uname, init : init }

#else +static inline void of_reserved_mem_device_init(struct device *dev) { } +static inline void of_reserved_mem_device_release(struct device *pdev) { } + 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) { }

Use recently introduced of_reserved_mem_device_init() function to automatically assign respective reserved memory region to the newly created platform and amba device.

Signed-off-by: Marek Szyprowski m.szyprowski@samsung.com --- drivers/of/platform.c | 7 +++++++ 1 file changed, 7 insertions(+)

diff --git a/drivers/of/platform.c b/drivers/of/platform.c index 404d1daebefa..3df0b1826e8b 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[] = { @@ -220,6 +221,8 @@ static 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 @@ -227,6 +230,7 @@ static 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; }

@@ -282,6 +286,8 @@ static struct amba_device *of_amba_device_create(struct device_node *node, else of_device_make_bus_id(&dev->dev);

+ of_reserved_mem_device_init(&dev->dev); + /* Allow the HW Peripheral ID to be overridden */ prop = of_get_property(node, "arm,primecell-periphid", NULL); if (prop) @@ -308,6 +314,7 @@ static struct amba_device *of_amba_device_create(struct device_node *node, return dev;

err_free: + of_reserved_mem_device_release(&dev->dev); amba_device_put(dev); return NULL; }

Refactor internal dma_contiguous_init_reserved_mem() function, which creates CMA area from previously reserved memory region and add support for handling 'shared-dma-pool' reserved-memory device tree nodes.

Based on previous code provided by Josh Cartwright joshc@codeaurora.org

Signed-off-by: Marek Szyprowski m.szyprowski@samsung.com --- drivers/base/dma-contiguous.c | 129 ++++++++++++++++++++++++++++++++++------- 1 file changed, 107 insertions(+), 22 deletions(-)

diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c index 165c2c299e57..0efdf1986990 100644 --- a/drivers/base/dma-contiguous.c +++ b/drivers/base/dma-contiguous.c @@ -182,6 +182,49 @@ static int __init cma_init_reserved_areas(void) core_initcall(cma_init_reserved_areas);

/** + * dma_contiguous_init_reserved_mem() - 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 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. + */ +static int __init dma_contiguous_init_reserved_mem(phys_addr_t size, + phys_addr_t base, struct cma **res_cma) +{ + struct cma *cma = &cma_areas[cma_area_count]; + phys_addr_t alignment; + + /* Sanity checks */ + if (cma_area_count == ARRAY_SIZE(cma_areas)) { + pr_err("Not enough slots for CMA reserved regions!\n"); + return -ENOSPC; + } + + if (!size || !memblock_is_region_reserved(base, size)) + return -EINVAL; + + /* Sanitise input arguments */ + alignment = PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order); + if (ALIGN(base, alignment) != base || ALIGN(size, alignment) != size) + return -EINVAL; + + cma->base_pfn = PFN_DOWN(base); + cma->count = size >> PAGE_SHIFT; + *res_cma = cma; + cma_area_count++; + + /* Architecture specific contiguous memory fixup. */ + dma_contiguous_early_fixup(base, size); + return 0; +} + +/** * 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 @@ -197,7 +240,6 @@ core_initcall(cma_init_reserved_areas); int __init dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base, phys_addr_t limit, struct cma **res_cma) { - struct cma *cma = &cma_areas[cma_area_count]; phys_addr_t alignment; int ret = 0;

@@ -205,12 +247,6 @@ int __init dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base, (unsigned long)size, (unsigned long)base, (unsigned long)limit);

- /* Sanity checks */ - if (cma_area_count == ARRAY_SIZE(cma_areas)) { - pr_err("Not enough slots for CMA reserved regions!\n"); - return -ENOSPC; - } - if (!size) return -EINVAL;

@@ -241,21 +277,12 @@ int __init dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base, } }

- /* - * Each reserved area must be initialised later, when more kernel - * subsystems (like slab allocator) are available. - */ - 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); - - /* Architecture specific contiguous memory fixup. */ - dma_contiguous_early_fixup(base, size); - return 0; + ret = dma_contiguous_init_reserved_mem(size, base, res_cma); + if (ret == 0) { + pr_info("CMA: reserved %ld MiB at %08lx\n", + (unsigned long)size / SZ_1M, (unsigned long)base); + return 0; + } err: pr_err("CMA: failed to reserve %ld MiB\n", (unsigned long)size / SZ_1M); return ret; @@ -357,3 +384,61 @@ bool dma_release_from_contiguous(struct device *dev, struct page *pages,

return true; } + +/* + * Support for reserved memory regions defined in device tree + */ +#ifdef CONFIG_OF_RESERVED_MEM +#include <linux/of.h> +#include <linux/of_fdt.h> +#include <linux/of_reserved_mem.h> + +#undef pr_fmt +#define pr_fmt(fmt) fmt + +static void rmem_cma_device_init(struct reserved_mem *rmem, struct device *dev) +{ + struct cma *cma = rmem->priv; + dev_set_cma_area(dev, cma); +} + +static const struct reserved_mem_ops rmem_cma_ops = { + .device_init = rmem_cma_device_init, +}; + +static int __init rmem_cma_setup(struct reserved_mem *rmem, + unsigned long node, + const char *uname) +{ + phys_addr_t align = PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order); + phys_addr_t mask = align - 1; + struct cma *cma; + int err; + + if (!of_get_flat_dt_prop(node, "reusable", NULL)) + return -EINVAL; + + if ((rmem->base & mask) || (rmem->size & mask)) { + pr_err("Reserved memory: incorrect alignment of CMA region\n"); + return -EINVAL; + } + + err = dma_contiguous_init_reserved_mem(rmem->size, rmem->base, &cma); + if (err) { + pr_err("Reserved memory: unable to setup CMA region\n"); + return err; + } + + if (of_get_flat_dt_prop(node, "linux,cma-default", NULL)) + dma_contiguous_set_default(cma); + + rmem->ops = &rmem_cma_ops; + rmem->priv = cma; + + pr_info("Reserved memory: created CMA memory pool at %pa, size %ld MiB\n", + &rmem->base, (unsigned long)rmem->size / SZ_1M); + + return 0; +} +RESERVEDMEM_OF_DECLARE(cma, "shared-dma-pool", rmem_cma_setup); +#endif

Enable reserved memory initialization from device tree.

Signed-off-by: Marek Szyprowski m.szyprowski@samsung.com --- arch/arm64/Kconfig | 1 + arch/arm64/mm/init.c | 1 + 2 files changed, 2 insertions(+)

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 27bbcfc7202a..6abf15407dca 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -43,6 +43,7 @@ config ARM64 select NO_BOOTMEM select OF select OF_EARLY_FLATTREE + select OF_RESERVED_MEM select PERF_USE_VMALLOC select POWER_RESET select POWER_SUPPLY diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index d0b4c2efda90..3fb8d50dfdaa 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -160,6 +160,7 @@ void __init arm64_memblock_init(void) memblock_reserve(base, size); }

+ early_init_fdt_scan_reserved_mem(); dma_contiguous_reserve(0);

memblock_allow_resize();