diff options
| -rw-r--r-- | Documentation/ramoops.txt | 13 | ||||
| -rw-r--r-- | fs/pstore/ram.c | 13 | ||||
| -rw-r--r-- | fs/pstore/ram_core.c | 31 | ||||
| -rw-r--r-- | include/linux/pstore_ram.h | 4 |
4 files changed, 47 insertions, 14 deletions
diff --git a/Documentation/ramoops.txt b/Documentation/ramoops.txt index 69b3cac4749d..5d8675615e59 100644 --- a/Documentation/ramoops.txt +++ b/Documentation/ramoops.txt @@ -14,11 +14,19 @@ survive after a restart. 1. Ramoops concepts -Ramoops uses a predefined memory area to store the dump. The start and size of -the memory area are set using two variables: +Ramoops uses a predefined memory area to store the dump. The start and size +and type of the memory area are set using three variables: * "mem_address" for the start * "mem_size" for the size. The memory size will be rounded down to a power of two. + * "mem_type" to specifiy if the memory type (default is pgprot_writecombine). + +Typically the default value of mem_type=0 should be used as that sets the pstore +mapping to pgprot_writecombine. Setting mem_type=1 attempts to use +pgprot_noncached, which only works on some platforms. This is because pstore +depends on atomic operations. At least on ARM, pgprot_noncached causes the +memory to be mapped strongly ordered, and atomic operations on strongly ordered +memory are implementation defined, and won't work on many ARMs such as omaps. The memory area is divided into "record_size" chunks (also rounded down to power of two) and each oops/panic writes a "record_size" chunk of @@ -55,6 +63,7 @@ Setting the ramoops parameters can be done in 2 different manners: static struct ramoops_platform_data ramoops_data = { .mem_size = <...>, .mem_address = <...>, + .mem_type = <...>, .record_size = <...>, .dump_oops = <...>, .ecc = <...>, diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c index ec881b312700..2f389ce5023c 100644 --- a/fs/pstore/ram.c +++ b/fs/pstore/ram.c @@ -61,6 +61,11 @@ module_param(mem_size, ulong, 0400); MODULE_PARM_DESC(mem_size, "size of reserved RAM used to store oops/panic logs"); +static unsigned int mem_type; +module_param(mem_type, uint, 0600); +MODULE_PARM_DESC(mem_type, + "set to 1 to try to use unbuffered memory (default 0)"); + static int dump_oops = 1; module_param(dump_oops, int, 0600); MODULE_PARM_DESC(dump_oops, @@ -79,6 +84,7 @@ struct ramoops_context { struct persistent_ram_zone *fprz; phys_addr_t phys_addr; unsigned long size; + unsigned int memtype; size_t record_size; size_t console_size; size_t ftrace_size; @@ -366,7 +372,8 @@ static int ramoops_init_przs(struct device *dev, struct ramoops_context *cxt, size_t sz = cxt->record_size; cxt->przs[i] = persistent_ram_new(*paddr, sz, 0, - &cxt->ecc_info); + &cxt->ecc_info, + cxt->memtype); if (IS_ERR(cxt->przs[i])) { err = PTR_ERR(cxt->przs[i]); dev_err(dev, "failed to request mem region (0x%zx@0x%llx): %d\n", @@ -396,7 +403,7 @@ static int ramoops_init_prz(struct device *dev, struct ramoops_context *cxt, return -ENOMEM; } - *prz = persistent_ram_new(*paddr, sz, sig, &cxt->ecc_info); + *prz = persistent_ram_new(*paddr, sz, sig, &cxt->ecc_info, cxt->memtype); if (IS_ERR(*prz)) { int err = PTR_ERR(*prz); @@ -443,6 +450,7 @@ static int ramoops_probe(struct platform_device *pdev) cxt->size = pdata->mem_size; cxt->phys_addr = pdata->mem_address; + cxt->memtype = pdata->mem_type; cxt->record_size = pdata->record_size; cxt->console_size = pdata->console_size; cxt->ftrace_size = pdata->ftrace_size; @@ -572,6 +580,7 @@ static void ramoops_register_dummy(void) dummy_data->mem_size = mem_size; dummy_data->mem_address = mem_address; + dummy_data->mem_type = 0; dummy_data->record_size = record_size; dummy_data->console_size = ramoops_console_size; dummy_data->ftrace_size = ramoops_ftrace_size; diff --git a/fs/pstore/ram_core.c b/fs/pstore/ram_core.c index 24f94b0f2270..76c3f80efdfa 100644 --- a/fs/pstore/ram_core.c +++ b/fs/pstore/ram_core.c @@ -380,7 +380,8 @@ void persistent_ram_zap(struct persistent_ram_zone *prz) persistent_ram_update_header_ecc(prz); } -static void *persistent_ram_vmap(phys_addr_t start, size_t size) +static void *persistent_ram_vmap(phys_addr_t start, size_t size, + unsigned int memtype) { struct page **pages; phys_addr_t page_start; @@ -392,7 +393,10 @@ static void *persistent_ram_vmap(phys_addr_t start, size_t size) page_start = start - offset_in_page(start); page_count = DIV_ROUND_UP(size + offset_in_page(start), PAGE_SIZE); - prot = pgprot_writecombine(PAGE_KERNEL); + if (memtype) + prot = pgprot_noncached(PAGE_KERNEL); + else + prot = pgprot_writecombine(PAGE_KERNEL); pages = kmalloc_array(page_count, sizeof(struct page *), GFP_KERNEL); if (!pages) { @@ -411,8 +415,11 @@ static void *persistent_ram_vmap(phys_addr_t start, size_t size) return vaddr; } -static void *persistent_ram_iomap(phys_addr_t start, size_t size) +static void *persistent_ram_iomap(phys_addr_t start, size_t size, + unsigned int memtype) { + void *va; + if (!request_mem_region(start, size, "persistent_ram")) { pr_err("request mem region (0x%llx@0x%llx) failed\n", (unsigned long long)size, (unsigned long long)start); @@ -422,19 +429,24 @@ static void *persistent_ram_iomap(phys_addr_t start, size_t size) buffer_start_add = buffer_start_add_locked; buffer_size_add = buffer_size_add_locked; - return ioremap_wc(start, size); + if (memtype) + va = ioremap(start, size); + else + va = ioremap_wc(start, size); + + return va; } static int persistent_ram_buffer_map(phys_addr_t start, phys_addr_t size, - struct persistent_ram_zone *prz) + struct persistent_ram_zone *prz, int memtype) { prz->paddr = start; prz->size = size; if (pfn_valid(start >> PAGE_SHIFT)) - prz->vaddr = persistent_ram_vmap(start, size); + prz->vaddr = persistent_ram_vmap(start, size, memtype); else - prz->vaddr = persistent_ram_iomap(start, size); + prz->vaddr = persistent_ram_iomap(start, size, memtype); if (!prz->vaddr) { pr_err("%s: Failed to map 0x%llx pages at 0x%llx\n", __func__, @@ -500,7 +512,8 @@ void persistent_ram_free(struct persistent_ram_zone *prz) } struct persistent_ram_zone *persistent_ram_new(phys_addr_t start, size_t size, - u32 sig, struct persistent_ram_ecc_info *ecc_info) + u32 sig, struct persistent_ram_ecc_info *ecc_info, + unsigned int memtype) { struct persistent_ram_zone *prz; int ret = -ENOMEM; @@ -511,7 +524,7 @@ struct persistent_ram_zone *persistent_ram_new(phys_addr_t start, size_t size, goto err; } - ret = persistent_ram_buffer_map(start, size, prz); + ret = persistent_ram_buffer_map(start, size, prz, memtype); if (ret) goto err; diff --git a/include/linux/pstore_ram.h b/include/linux/pstore_ram.h index 9974975d40db..4af3fdc85b01 100644 --- a/include/linux/pstore_ram.h +++ b/include/linux/pstore_ram.h @@ -53,7 +53,8 @@ struct persistent_ram_zone { }; struct persistent_ram_zone *persistent_ram_new(phys_addr_t start, size_t size, - u32 sig, struct persistent_ram_ecc_info *ecc_info); + u32 sig, struct persistent_ram_ecc_info *ecc_info, + unsigned int memtype); void persistent_ram_free(struct persistent_ram_zone *prz); void persistent_ram_zap(struct persistent_ram_zone *prz); @@ -76,6 +77,7 @@ ssize_t persistent_ram_ecc_string(struct persistent_ram_zone *prz, struct ramoops_platform_data { unsigned long mem_size; unsigned long mem_address; + unsigned int mem_type; unsigned long record_size; unsigned long console_size; unsigned long ftrace_size; |