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..3da0ebdba8d9 --- /dev/null +++ b/Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt @@ -0,0 +1,133 @@ +*** 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 (@
) 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 ,[-] +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; + size = <0x4000000>; + alignment = <0x2000>; + linux,cma-default; + }; + + display_reserved: framebuffer@78000000 { + reg = <0x78000000 0x800000>; + }; + + multimedia_reserved: multimedia@77000000 { + compatible = "acme,multimedia-memory"; + reg = <0x77000000 0x4000000>; + }; + }; + + /* ... */ + + fb0: video@12300000 { + memory-region = <&display_reserved>; + /* ... */ + }; + + scaler: scaler@12500000 { + memory-region = <&multimedia_reserved>; + /* ... */ + }; + + codec: codec@12600000 { + memory-region = <&multimedia_reserved>; + /* ... */ + }; +}; diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index e25419817791..d0262bea8020 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -1918,6 +1918,7 @@ config USE_OF select IRQ_DOMAIN select OF select OF_EARLY_FLATTREE + select OF_RESERVED_MEM help Include support for flattened device tree machine descriptions. diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c index 804d61566a53..2a77ba8796ae 100644 --- a/arch/arm/mm/init.c +++ b/arch/arm/mm/init.c @@ -323,6 +323,8 @@ void __init arm_memblock_init(struct meminfo *mi, if (mdesc->reserve) mdesc->reserve(); + early_init_fdt_scan_reserved_mem(); + /* * reserve memory for DMA contigouos allocations, * must come from DMA area inside low memory 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(); diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 957bf344c0f5..3b6617fed8fc 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -90,6 +90,7 @@ config PPC select BINFMT_ELF select OF select OF_EARLY_FLATTREE + select OF_RESERVED_MEM select HAVE_FTRACE_MCOUNT_RECORD select HAVE_DYNAMIC_FTRACE select HAVE_FUNCTION_TRACER diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c index f58c0d3aaeb4..591986215801 100644 --- a/arch/powerpc/kernel/prom.c +++ b/arch/powerpc/kernel/prom.c @@ -33,6 +33,7 @@ #include #include #include +#include #include #include @@ -588,6 +589,8 @@ static void __init early_reserve_mem_dt(void) memblock_reserve(base, size); } } + + early_init_fdt_scan_reserved_mem(); } static void __init early_reserve_mem(void) diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig index a46ac1b00032..889005fa4d04 100644 --- a/drivers/of/Kconfig +++ b/drivers/of/Kconfig @@ -71,4 +71,10 @@ 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 70ccc36513e7..fa16a912a927 100644 --- a/drivers/of/fdt.c +++ b/drivers/of/fdt.c @@ -15,6 +15,8 @@ #include #include #include +#include +#include #include #include #include @@ -439,6 +441,129 @@ 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, first = 1; + + 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; + if (first) { + fdt_reserved_mem_save_node(node, uname, base, size); + first = 0; + } + } + 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; + int err; + + 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; + + 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; +} + +/** + * 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) +{ + if (!initial_boot_params) + return; + + of_scan_flat_dt(__fdt_scan_reserved_mem, NULL); + fdt_init_reserved_mem(); +} + /** * of_scan_flat_dt - scan flattened tree blob and call callback on each. * @it: callback function @@ -856,6 +981,16 @@ 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 +999,14 @@ 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/drivers/of/of_reserved_mem.c b/drivers/of/of_reserved_mem.c new file mode 100644 index 000000000000..daaaf935911d --- /dev/null +++ b/drivers/of/of_reserved_mem.c @@ -0,0 +1,217 @@ +/* + * 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 + * Author: Josh Cartwright + * + * 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 +#include +#include +#include +#include +#include +#include + +#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 +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; +} + +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 + */ +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); + 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_fdt.h b/include/linux/of_fdt.h index 2b77058a7335..ddd7219af8ac 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); @@ -118,6 +121,7 @@ extern void unflatten_and_copy_device_tree(void); extern void early_init_devtree(void *); extern void early_get_first_memblock_info(void *, phys_addr_t *); #else /* CONFIG_OF_FLATTREE */ +static inline void early_init_fdt_scan_reserved_mem(void) {} static inline const char *of_flat_dt_get_machine_name(void) { return NULL; } static inline void unflatten_device_tree(void) {} static inline void unflatten_and_copy_device_tree(void) {} diff --git a/include/linux/of_reserved_mem.h b/include/linux/of_reserved_mem.h new file mode 100644 index 000000000000..9b1fbb7f29fc --- /dev/null +++ b/include/linux/of_reserved_mem.h @@ -0,0 +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 */