From 3ccc00a7e04ff7718c9aebb4b0c982571c798759 Mon Sep 17 00:00:00 2001 From: Mahesh Salgaonkar Date: Mon, 20 Feb 2012 02:15:03 +0000 Subject: [PATCH] fadump: Register for firmware assisted dump. On 2012-02-20 11:02:51 Mon, Paul Mackerras wrote: > On Thu, Feb 16, 2012 at 04:44:30PM +0530, Mahesh J Salgaonkar wrote: > > If I have read the code correctly, we are going to get this printk on > non-pSeries machines or on older pSeries machines, even if the user > has not put the fadump=on option on the kernel command line. The > printk will be annoying since there is no actual error condition. It > seems to me that the condition for the printk should include > fw_dump.fadump_enabled. In other words you should probably add > > if (!fw_dump.fadump_enabled) > return 0; > > at the beginning of the function. Hi Paul, Thanks for pointing it out. Please find the updated patch below. The existing patches above this (4/10 through 10/10) cleanly applies on this update. Thanks, -Mahesh. Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/include/asm/fadump.h | 57 +++++ arch/powerpc/kernel/fadump.c | 355 +++++++++++++++++++++++++++++- arch/powerpc/kernel/iommu.c | 8 +- arch/powerpc/mm/hash_utils_64.c | 11 + 4 files changed, 427 insertions(+), 4 deletions(-) diff --git a/arch/powerpc/include/asm/fadump.h b/arch/powerpc/include/asm/fadump.h index 7be25d30d985..bbaf278bdccc 100644 --- a/arch/powerpc/include/asm/fadump.h +++ b/arch/powerpc/include/asm/fadump.h @@ -48,6 +48,58 @@ #define FADUMP_HPTE_REGION 0x0002 #define FADUMP_REAL_MODE_REGION 0x0011 +/* Dump request flag */ +#define FADUMP_REQUEST_FLAG 0x00000001 + +/* FAD commands */ +#define FADUMP_REGISTER 1 +#define FADUMP_UNREGISTER 2 +#define FADUMP_INVALIDATE 3 + +/* Kernel Dump section info */ +struct fadump_section { + u32 request_flag; + u16 source_data_type; + u16 error_flags; + u64 source_address; + u64 source_len; + u64 bytes_dumped; + u64 destination_address; +}; + +/* ibm,configure-kernel-dump header. */ +struct fadump_section_header { + u32 dump_format_version; + u16 dump_num_sections; + u16 dump_status_flag; + u32 offset_first_dump_section; + + /* Fields for disk dump option. */ + u32 dd_block_size; + u64 dd_block_offset; + u64 dd_num_blocks; + u32 dd_offset_disk_path; + + /* Maximum time allowed to prevent an automatic dump-reboot. */ + u32 max_time_auto; +}; + +/* + * Firmware Assisted dump memory structure. This structure is required for + * registering future kernel dump with power firmware through rtas call. + * + * No disk dump option. Hence disk dump path string section is not included. + */ +struct fadump_mem_struct { + struct fadump_section_header header; + + /* Kernel dump sections */ + struct fadump_section cpu_state_data; + struct fadump_section hpte_region; + struct fadump_section rmr_region; +}; + +/* Firmware-assisted dump configuration details. */ struct fw_dump { unsigned long cpu_state_data_size; unsigned long hpte_region_size; @@ -62,10 +114,15 @@ struct fw_dump { unsigned long fadump_enabled:1; unsigned long fadump_supported:1; unsigned long dump_active:1; + unsigned long dump_registered:1; }; extern int early_init_dt_scan_fw_dump(unsigned long node, const char *uname, int depth, void *data); extern int fadump_reserve_mem(void); +extern int setup_fadump(void); +extern int is_fadump_active(void); +#else /* CONFIG_FA_DUMP */ +static inline int is_fadump_active(void) { return 0; } #endif #endif diff --git a/arch/powerpc/kernel/fadump.c b/arch/powerpc/kernel/fadump.c index deb276a9ce71..eb8f782afade 100644 --- a/arch/powerpc/kernel/fadump.c +++ b/arch/powerpc/kernel/fadump.c @@ -29,6 +29,9 @@ #include #include +#include +#include +#include #include #include @@ -36,6 +39,10 @@ #include static struct fw_dump fw_dump; +static struct fadump_mem_struct fdm; +static const struct fadump_mem_struct *fdm_active; + +static DEFINE_MUTEX(fadump_mutex); /* Scan the Firmware Assisted dump configuration details. */ int __init early_init_dt_scan_fw_dump(unsigned long node, @@ -64,7 +71,8 @@ int __init early_init_dt_scan_fw_dump(unsigned long node, * The 'ibm,kernel-dump' rtas node is present only if there is * dump data waiting for us. */ - if (of_get_flat_dt_prop(node, "ibm,kernel-dump", NULL)) + fdm_active = of_get_flat_dt_prop(node, "ibm,kernel-dump", NULL); + if (fdm_active) fw_dump.dump_active = 1; /* Get the sizes required to store dump data for the firmware provided @@ -98,6 +106,85 @@ int __init early_init_dt_scan_fw_dump(unsigned long node, return 1; } +int is_fadump_active(void) +{ + return fw_dump.dump_active; +} + +/* Print firmware assisted dump configurations for debugging purpose. */ +static void fadump_show_config(void) +{ + pr_debug("Support for firmware-assisted dump (fadump): %s\n", + (fw_dump.fadump_supported ? "present" : "no support")); + + if (!fw_dump.fadump_supported) + return; + + pr_debug("Fadump enabled : %s\n", + (fw_dump.fadump_enabled ? "yes" : "no")); + pr_debug("Dump Active : %s\n", + (fw_dump.dump_active ? "yes" : "no")); + pr_debug("Dump section sizes:\n"); + pr_debug(" CPU state data size: %lx\n", fw_dump.cpu_state_data_size); + pr_debug(" HPTE region size : %lx\n", fw_dump.hpte_region_size); + pr_debug("Boot memory size : %lx\n", fw_dump.boot_memory_size); +} + +static unsigned long init_fadump_mem_struct(struct fadump_mem_struct *fdm, + unsigned long addr) +{ + if (!fdm) + return 0; + + memset(fdm, 0, sizeof(struct fadump_mem_struct)); + addr = addr & PAGE_MASK; + + fdm->header.dump_format_version = 0x00000001; + fdm->header.dump_num_sections = 3; + fdm->header.dump_status_flag = 0; + fdm->header.offset_first_dump_section = + (u32)offsetof(struct fadump_mem_struct, cpu_state_data); + + /* + * Fields for disk dump option. + * We are not using disk dump option, hence set these fields to 0. + */ + fdm->header.dd_block_size = 0; + fdm->header.dd_block_offset = 0; + fdm->header.dd_num_blocks = 0; + fdm->header.dd_offset_disk_path = 0; + + /* set 0 to disable an automatic dump-reboot. */ + fdm->header.max_time_auto = 0; + + /* Kernel dump sections */ + /* cpu state data section. */ + fdm->cpu_state_data.request_flag = FADUMP_REQUEST_FLAG; + fdm->cpu_state_data.source_data_type = FADUMP_CPU_STATE_DATA; + fdm->cpu_state_data.source_address = 0; + fdm->cpu_state_data.source_len = fw_dump.cpu_state_data_size; + fdm->cpu_state_data.destination_address = addr; + addr += fw_dump.cpu_state_data_size; + + /* hpte region section */ + fdm->hpte_region.request_flag = FADUMP_REQUEST_FLAG; + fdm->hpte_region.source_data_type = FADUMP_HPTE_REGION; + fdm->hpte_region.source_address = 0; + fdm->hpte_region.source_len = fw_dump.hpte_region_size; + fdm->hpte_region.destination_address = addr; + addr += fw_dump.hpte_region_size; + + /* RMA region section */ + fdm->rmr_region.request_flag = FADUMP_REQUEST_FLAG; + fdm->rmr_region.source_data_type = FADUMP_REAL_MODE_REGION; + fdm->rmr_region.source_address = RMA_START; + fdm->rmr_region.source_len = fw_dump.boot_memory_size; + fdm->rmr_region.destination_address = addr; + addr += fw_dump.boot_memory_size; + + return addr; +} + /** * fadump_calculate_reserve_size(): reserve variable boot area 5% of System RAM * @@ -166,8 +253,15 @@ int __init fadump_reserve_mem(void) fw_dump.fadump_enabled = 0; return 0; } - /* Initialize boot memory size */ - fw_dump.boot_memory_size = fadump_calculate_reserve_size(); + /* + * Initialize boot memory size + * If dump is active then we have already calculated the size during + * first kernel. + */ + if (fdm_active) + fw_dump.boot_memory_size = fdm_active->rmr_region.source_len; + else + fw_dump.boot_memory_size = fadump_calculate_reserve_size(); /* * Calculate the memory boundary. @@ -244,3 +338,258 @@ static int __init early_fadump_reserve_mem(char *p) return 0; } early_param("fadump_reserve_mem", early_fadump_reserve_mem); + +static void register_fw_dump(struct fadump_mem_struct *fdm) +{ + int rc; + unsigned int wait_time; + + pr_debug("Registering for firmware-assisted kernel dump...\n"); + + /* TODO: Add upper time limit for the delay */ + do { + rc = rtas_call(fw_dump.ibm_configure_kernel_dump, 3, 1, NULL, + FADUMP_REGISTER, fdm, + sizeof(struct fadump_mem_struct)); + + wait_time = rtas_busy_delay_time(rc); + if (wait_time) + mdelay(wait_time); + + } while (wait_time); + + switch (rc) { + case -1: + printk(KERN_ERR "Failed to register firmware-assisted kernel" + " dump. Hardware Error(%d).\n", rc); + break; + case -3: + printk(KERN_ERR "Failed to register firmware-assisted kernel" + " dump. Parameter Error(%d).\n", rc); + break; + case -9: + printk(KERN_ERR "firmware-assisted kernel dump is already " + " registered."); + fw_dump.dump_registered = 1; + break; + case 0: + printk(KERN_INFO "firmware-assisted kernel dump registration" + " is successful\n"); + fw_dump.dump_registered = 1; + break; + } +} + +static void register_fadump(void) +{ + /* + * If no memory is reserved then we can not register for firmware- + * assisted dump. + */ + if (!fw_dump.reserve_dump_area_size) + return; + + /* register the future kernel dump with firmware. */ + register_fw_dump(&fdm); +} + +static int fadump_unregister_dump(struct fadump_mem_struct *fdm) +{ + int rc = 0; + unsigned int wait_time; + + pr_debug("Un-register firmware-assisted dump\n"); + + /* TODO: Add upper time limit for the delay */ + do { + rc = rtas_call(fw_dump.ibm_configure_kernel_dump, 3, 1, NULL, + FADUMP_UNREGISTER, fdm, + sizeof(struct fadump_mem_struct)); + + wait_time = rtas_busy_delay_time(rc); + if (wait_time) + mdelay(wait_time); + } while (wait_time); + + if (rc) { + printk(KERN_ERR "Failed to un-register firmware-assisted dump." + " unexpected error(%d).\n", rc); + return rc; + } + fw_dump.dump_registered = 0; + return 0; +} + +static ssize_t fadump_enabled_show(struct kobject *kobj, + struct kobj_attribute *attr, + char *buf) +{ + return sprintf(buf, "%d\n", fw_dump.fadump_enabled); +} + +static ssize_t fadump_register_show(struct kobject *kobj, + struct kobj_attribute *attr, + char *buf) +{ + return sprintf(buf, "%d\n", fw_dump.dump_registered); +} + +static ssize_t fadump_register_store(struct kobject *kobj, + struct kobj_attribute *attr, + const char *buf, size_t count) +{ + int ret = 0; + + if (!fw_dump.fadump_enabled || fdm_active) + return -EPERM; + + mutex_lock(&fadump_mutex); + + switch (buf[0]) { + case '0': + if (fw_dump.dump_registered == 0) { + ret = -EINVAL; + goto unlock_out; + } + /* Un-register Firmware-assisted dump */ + fadump_unregister_dump(&fdm); + break; + case '1': + if (fw_dump.dump_registered == 1) { + ret = -EINVAL; + goto unlock_out; + } + /* Register Firmware-assisted dump */ + register_fadump(); + break; + default: + ret = -EINVAL; + break; + } + +unlock_out: + mutex_unlock(&fadump_mutex); + return ret < 0 ? ret : count; +} + +static int fadump_region_show(struct seq_file *m, void *private) +{ + const struct fadump_mem_struct *fdm_ptr; + + if (!fw_dump.fadump_enabled) + return 0; + + if (fdm_active) + fdm_ptr = fdm_active; + else + fdm_ptr = &fdm; + + seq_printf(m, + "CPU : [%#016llx-%#016llx] %#llx bytes, " + "Dumped: %#llx\n", + fdm_ptr->cpu_state_data.destination_address, + fdm_ptr->cpu_state_data.destination_address + + fdm_ptr->cpu_state_data.source_len - 1, + fdm_ptr->cpu_state_data.source_len, + fdm_ptr->cpu_state_data.bytes_dumped); + seq_printf(m, + "HPTE: [%#016llx-%#016llx] %#llx bytes, " + "Dumped: %#llx\n", + fdm_ptr->hpte_region.destination_address, + fdm_ptr->hpte_region.destination_address + + fdm_ptr->hpte_region.source_len - 1, + fdm_ptr->hpte_region.source_len, + fdm_ptr->hpte_region.bytes_dumped); + seq_printf(m, + "DUMP: [%#016llx-%#016llx] %#llx bytes, " + "Dumped: %#llx\n", + fdm_ptr->rmr_region.destination_address, + fdm_ptr->rmr_region.destination_address + + fdm_ptr->rmr_region.source_len - 1, + fdm_ptr->rmr_region.source_len, + fdm_ptr->rmr_region.bytes_dumped); + + if (!fdm_active || + (fw_dump.reserve_dump_area_start == + fdm_ptr->cpu_state_data.destination_address)) + return 0; + + /* Dump is active. Show reserved memory region. */ + seq_printf(m, + " : [%#016llx-%#016llx] %#llx bytes, " + "Dumped: %#llx\n", + (unsigned long long)fw_dump.reserve_dump_area_start, + fdm_ptr->cpu_state_data.destination_address - 1, + fdm_ptr->cpu_state_data.destination_address - + fw_dump.reserve_dump_area_start, + fdm_ptr->cpu_state_data.destination_address - + fw_dump.reserve_dump_area_start); + return 0; +} + +static struct kobj_attribute fadump_attr = __ATTR(fadump_enabled, + 0444, fadump_enabled_show, + NULL); +static struct kobj_attribute fadump_register_attr = __ATTR(fadump_registered, + 0644, fadump_register_show, + fadump_register_store); + +static int fadump_region_open(struct inode *inode, struct file *file) +{ + return single_open(file, fadump_region_show, inode->i_private); +} + +static const struct file_operations fadump_region_fops = { + .open = fadump_region_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +static void fadump_init_files(void) +{ + struct dentry *debugfs_file; + int rc = 0; + + rc = sysfs_create_file(kernel_kobj, &fadump_attr.attr); + if (rc) + printk(KERN_ERR "fadump: unable to create sysfs file" + " fadump_enabled (%d)\n", rc); + + rc = sysfs_create_file(kernel_kobj, &fadump_register_attr.attr); + if (rc) + printk(KERN_ERR "fadump: unable to create sysfs file" + " fadump_registered (%d)\n", rc); + + debugfs_file = debugfs_create_file("fadump_region", 0444, + powerpc_debugfs_root, NULL, + &fadump_region_fops); + if (!debugfs_file) + printk(KERN_ERR "fadump: unable to create debugfs file" + " fadump_region\n"); + return; +} + +/* + * Prepare for firmware-assisted dump. + */ +int __init setup_fadump(void) +{ + if (!fw_dump.fadump_enabled) + return 0; + + if (!fw_dump.fadump_supported) { + printk(KERN_ERR "Firmware-assisted dump is not supported on" + " this hardware\n"); + return 0; + } + + fadump_show_config(); + /* Initialize the kernel dump memory structure for FAD registration. */ + if (fw_dump.reserve_dump_area_size) + init_fadump_mem_struct(&fdm, fw_dump.reserve_dump_area_start); + fadump_init_files(); + + return 1; +} +subsys_initcall(setup_fadump); diff --git a/arch/powerpc/kernel/iommu.c b/arch/powerpc/kernel/iommu.c index 0cfcf98aafca..359f078571c7 100644 --- a/arch/powerpc/kernel/iommu.c +++ b/arch/powerpc/kernel/iommu.c @@ -39,6 +39,7 @@ #include #include #include +#include #define DBG(...) @@ -445,7 +446,12 @@ void iommu_unmap_sg(struct iommu_table *tbl, struct scatterlist *sglist, static void iommu_table_clear(struct iommu_table *tbl) { - if (!is_kdump_kernel()) { + /* + * In case of firmware assisted dump system goes through clean + * reboot process at the time of system crash. Hence it's safe to + * clear the TCE entries if firmware assisted dump is active. + */ + if (!is_kdump_kernel() || is_fadump_active()) { /* Clear the table in case firmware left allocations in it */ ppc_md.tce_free(tbl, tbl->it_offset, tbl->it_size); return; diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c index 2d282186cb45..b534bbac3f82 100644 --- a/arch/powerpc/mm/hash_utils_64.c +++ b/arch/powerpc/mm/hash_utils_64.c @@ -55,6 +55,7 @@ #include #include #include +#include #ifdef DEBUG #define DBG(fmt...) udbg_printf(fmt) @@ -625,6 +626,16 @@ static void __init htab_initialize(void) /* Using a hypervisor which owns the htab */ htab_address = NULL; _SDR1 = 0; +#ifdef CONFIG_FA_DUMP + /* + * If firmware assisted dump is active firmware preserves + * the contents of htab along with entire partition memory. + * Clear the htab if firmware assisted dump is active so + * that we dont end up using old mappings. + */ + if (is_fadump_active() && ppc_md.hpte_clear_all) + ppc_md.hpte_clear_all(); +#endif } else { /* Find storage for the HPT. Must be contiguous in * the absolute address space. On cell we want it to be -- GitLab