| Message ID | 1393594976-16728-3-git-send-email-m.szyprowski@samsung.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, 28 Feb 2014 14:42:47 +0100, Marek Szyprowski <m.szyprowski@samsung.com> wrote: > 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> Applied, thanks. g. > --- > 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); > > -- > 1.7.9.5 >
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);