pseries/fadump: move out platform specific support from generic code (f3512011) · Commits · EulixOS / Software / Kernel

arch/powerpc/kernel/fadump.c

+14 −315

Original line number	Diff line number	Diff line
		@@ -28,15 +28,11 @@
		#include <asm/debugfs.h>
		#include <asm/page.h>
		#include <asm/prom.h>
		#include <asm/rtas.h>
		#include <asm/fadump.h>
		#include <asm/fadump-internal.h>
		#include <asm/setup.h>

		#include "../platforms/pseries/rtas-fadump.h"

		static struct fw_dump fw_dump;
		static const struct rtas_fadump_mem_struct *fdm_active;

		static DEFINE_MUTEX(fadump_mutex);
		struct fad_crash_memory_ranges *crash_memory_ranges;
		@@ -108,22 +104,13 @@ static int __init fadump_cma_init(void) { return 1; }
		#endif /* CONFIG_CMA */

		/* Scan the Firmware Assisted dump configuration details. */
		int __init early_init_dt_scan_fw_dump(unsigned long node,
		const char uname, int depth, void data)
		int __init early_init_dt_scan_fw_dump(unsigned long node, const char *uname,
		int depth, void *data)
		{
		if (depth != 1 \|\| strcmp(uname, "rtas") != 0)
		return 0;

		rtas_fadump_dt_scan(&fw_dump, node);

		/*
		* The 'ibm,kernel-dump' rtas node is present only if there is
		* dump data waiting for us.
		*/
		fdm_active = of_get_flat_dt_prop(node, "ibm,kernel-dump", NULL);
		if (fdm_active)
		fw_dump.dump_active = 1;

		return 1;
		}

		@@ -358,9 +345,7 @@ int __init fadump_reserve_mem(void)
		* If dump is active then we have already calculated the size during
		* first kernel.
		*/
		if (fdm_active)
		fw_dump.boot_memory_size = be64_to_cpu(fdm_active->rmr_region.source_len);
		else {
		if (!fw_dump.dump_active) {
		fw_dump.boot_memory_size = fadump_calculate_reserve_size();
		#ifdef CONFIG_CMA
		if (!fw_dump.nocma)
		@@ -414,17 +399,9 @@ int __init fadump_reserve_mem(void)
		size = memory_boundary - base;
		fadump_reserve_crash_area(base, size);

		fw_dump.fadumphdr_addr =
		be64_to_cpu(fdm_active->rmr_region.destination_address) +
		be64_to_cpu(fdm_active->rmr_region.source_len);
		pr_debug("fadumphdr_addr = %pa\n", &fw_dump.fadumphdr_addr);

		/*
		* Start address of reserve dump area (permanent reservation)
		* for re-registering FADump after dump capture.
		*/
		fw_dump.reserve_dump_area_start =
		be64_to_cpu(fdm_active->cpu_state_data.destination_address);
		pr_debug("fadumphdr_addr = %#016lx\n", fw_dump.fadumphdr_addr);
		pr_debug("Reserve dump area start address: 0x%lx\n",
		fw_dump.reserve_dump_area_start);
		} else {
		/*
		* Reserve memory at an offset closer to bottom of the RAM to
		@@ -539,66 +516,6 @@ void crash_fadump(struct pt_regs regs, const char str)
		fw_dump.ops->fadump_trigger(fdh, str);
		}

		#define GPR_MASK 0xffffff0000000000
		static inline int fadump_gpr_index(u64 id)
		{
		int i = -1;
		char str[3];

		if ((id & GPR_MASK) == fadump_str_to_u64("GPR")) {
		/* get the digits at the end */
		id &= ~GPR_MASK;
		id >>= 24;
		str[2] = '\0';
		str[1] = id & 0xff;
		str[0] = (id >> 8) & 0xff;
		sscanf(str, "%d", &i);
		if (i > 31)
		i = -1;
		}
		return i;
		}

		static inline void fadump_set_regval(struct pt_regs *regs, u64 reg_id,
		u64 reg_val)
		{
		int i;

		i = fadump_gpr_index(reg_id);
		if (i >= 0)
		regs->gpr[i] = (unsigned long)reg_val;
		else if (reg_id == fadump_str_to_u64("NIA"))
		regs->nip = (unsigned long)reg_val;
		else if (reg_id == fadump_str_to_u64("MSR"))
		regs->msr = (unsigned long)reg_val;
		else if (reg_id == fadump_str_to_u64("CTR"))
		regs->ctr = (unsigned long)reg_val;
		else if (reg_id == fadump_str_to_u64("LR"))
		regs->link = (unsigned long)reg_val;
		else if (reg_id == fadump_str_to_u64("XER"))
		regs->xer = (unsigned long)reg_val;
		else if (reg_id == fadump_str_to_u64("CR"))
		regs->ccr = (unsigned long)reg_val;
		else if (reg_id == fadump_str_to_u64("DAR"))
		regs->dar = (unsigned long)reg_val;
		else if (reg_id == fadump_str_to_u64("DSISR"))
		regs->dsisr = (unsigned long)reg_val;
		}

		static struct rtas_fadump_reg_entry*
		fadump_read_registers(struct rtas_fadump_reg_entry reg_entry, struct pt_regs regs)
		{
		memset(regs, 0, sizeof(struct pt_regs));

		while (be64_to_cpu(reg_entry->reg_id) != fadump_str_to_u64("CPUEND")) {
		fadump_set_regval(regs, be64_to_cpu(reg_entry->reg_id),
		be64_to_cpu(reg_entry->reg_value));
		reg_entry++;
		}
		reg_entry++;
		return reg_entry;
		}

		u32 fadump_regs_to_elf_notes(u32 buf, struct pt_regs *regs)
		{
		struct elf_prstatus prstatus;
		@@ -686,147 +603,6 @@ void fadump_free_cpu_notes_buf(void)
		fw_dump.cpu_notes_buf_size = 0;
		}

		/*
		* Read CPU state dump data and convert it into ELF notes.
		* The CPU dump starts with magic number "REGSAVE". NumCpusOffset should be
		* used to access the data to allow for additional fields to be added without
		* affecting compatibility. Each list of registers for a CPU starts with
		* "CPUSTRT" and ends with "CPUEND". Each register entry is of 16 bytes,
		* 8 Byte ASCII identifier and 8 Byte register value. The register entry
		* with identifier "CPUSTRT" and "CPUEND" contains 4 byte cpu id as part
		* of register value. For more details refer to PAPR document.
		*
		* Only for the crashing cpu we ignore the CPU dump data and get exact
		* state from fadump crash info structure populated by first kernel at the
		* time of crash.
		*/
		static int __init fadump_build_cpu_notes(const struct rtas_fadump_mem_struct *fdm)
		{
		struct rtas_fadump_reg_save_area_header *reg_header;
		struct rtas_fadump_reg_entry *reg_entry;
		struct fadump_crash_info_header *fdh = NULL;
		void *vaddr;
		unsigned long addr;
		u32 num_cpus, *note_buf;
		struct pt_regs regs;
		int i, rc = 0, cpu = 0;

		if (!fdm->cpu_state_data.bytes_dumped)
		return -EINVAL;

		addr = be64_to_cpu(fdm->cpu_state_data.destination_address);
		vaddr = __va(addr);

		reg_header = vaddr;
		if (be64_to_cpu(reg_header->magic_number) !=
		fadump_str_to_u64("REGSAVE")) {
		printk(KERN_ERR "Unable to read register save area.\n");
		return -ENOENT;
		}
		pr_debug("--------CPU State Data------------\n");
		pr_debug("Magic Number: %llx\n", be64_to_cpu(reg_header->magic_number));
		pr_debug("NumCpuOffset: %x\n", be32_to_cpu(reg_header->num_cpu_offset));

		vaddr += be32_to_cpu(reg_header->num_cpu_offset);
		num_cpus = be32_to_cpu(((__be32 )(vaddr)));
		pr_debug("NumCpus : %u\n", num_cpus);
		vaddr += sizeof(u32);
		reg_entry = (struct rtas_fadump_reg_entry *)vaddr;

		rc = fadump_setup_cpu_notes_buf(num_cpus);
		if (rc != 0)
		return rc;

		note_buf = (u32 *)fw_dump.cpu_notes_buf_vaddr;

		if (fw_dump.fadumphdr_addr)
		fdh = __va(fw_dump.fadumphdr_addr);

		for (i = 0; i < num_cpus; i++) {
		if (be64_to_cpu(reg_entry->reg_id) != fadump_str_to_u64("CPUSTRT")) {
		printk(KERN_ERR "Unable to read CPU state data\n");
		rc = -ENOENT;
		goto error_out;
		}
		/* Lower 4 bytes of reg_value contains logical cpu id */
		cpu = be64_to_cpu(reg_entry->reg_value) & RTAS_FADUMP_CPU_ID_MASK;
		if (fdh && !cpumask_test_cpu(cpu, &fdh->online_mask)) {
		RTAS_FADUMP_SKIP_TO_NEXT_CPU(reg_entry);
		continue;
		}
		pr_debug("Reading register data for cpu %d...\n", cpu);
		if (fdh && fdh->crashing_cpu == cpu) {
		regs = fdh->regs;
		note_buf = fadump_regs_to_elf_notes(note_buf, &regs);
		RTAS_FADUMP_SKIP_TO_NEXT_CPU(reg_entry);
		} else {
		reg_entry++;
		reg_entry = fadump_read_registers(reg_entry, &regs);
		note_buf = fadump_regs_to_elf_notes(note_buf, &regs);
		}
		}
		final_note(note_buf);

		if (fdh) {
		pr_debug("Updating elfcore header (%llx) with cpu notes\n",
		fdh->elfcorehdr_addr);
		fadump_update_elfcore_header((char *)__va(fdh->elfcorehdr_addr));
		}
		return 0;

		error_out:
		fadump_free_cpu_notes_buf();
		return rc;

		}

		/*
		* Validate and process the dump data stored by firmware before exporting
		* it through '/proc/vmcore'.
		*/
		static int __init process_fadump(const struct rtas_fadump_mem_struct *fdm_active)
		{
		struct fadump_crash_info_header *fdh;
		int rc = 0;

		if (!fdm_active \|\| !fw_dump.fadumphdr_addr)
		return -EINVAL;

		/* Check if the dump data is valid. */
		if ((be16_to_cpu(fdm_active->header.dump_status_flag) == RTAS_FADUMP_ERROR_FLAG) \|\|
		(fdm_active->cpu_state_data.error_flags != 0) \|\|
		(fdm_active->rmr_region.error_flags != 0)) {
		printk(KERN_ERR "Dump taken by platform is not valid\n");
		return -EINVAL;
		}
		if ((fdm_active->rmr_region.bytes_dumped !=
		fdm_active->rmr_region.source_len) \|\|
		!fdm_active->cpu_state_data.bytes_dumped) {
		printk(KERN_ERR "Dump taken by platform is incomplete\n");
		return -EINVAL;
		}

		/* Validate the fadump crash info header */
		fdh = __va(fw_dump.fadumphdr_addr);
		if (fdh->magic_number != FADUMP_CRASH_INFO_MAGIC) {
		printk(KERN_ERR "Crash info header is not valid.\n");
		return -EINVAL;
		}

		rc = fadump_build_cpu_notes(fdm_active);
		if (rc)
		return rc;

		/*
		* We are done validating dump info and elfcore header is now ready
		* to be exported. set elfcorehdr_addr so that vmcore module will
		* export the elfcore header through '/proc/vmcore'.
		*/
		elfcorehdr_addr = fdh->elfcorehdr_addr;

		return 0;
		}

		static void free_crash_memory_ranges(void)
		{
		kfree(crash_memory_ranges);
		@@ -1116,7 +892,6 @@ static unsigned long init_fadump_header(unsigned long addr)
		if (!addr)
		return 0;

		fw_dump.fadumphdr_addr = addr;
		fdh = __va(addr);
		addr += sizeof(struct fadump_crash_info_header);

		@@ -1160,39 +935,12 @@ static int register_fadump(void)
		return fw_dump.ops->fadump_register(&fw_dump);
		}

		static int fadump_invalidate_dump(const struct rtas_fadump_mem_struct *fdm)
		{
		int rc = 0;
		unsigned int wait_time;

		pr_debug("Invalidating firmware-assisted dump registration\n");

		/* TODO: Add upper time limit for the delay */
		do {
		rc = rtas_call(fw_dump.ibm_configure_kernel_dump, 3, 1, NULL,
		FADUMP_INVALIDATE, fdm,
		sizeof(struct rtas_fadump_mem_struct));

		wait_time = rtas_busy_delay_time(rc);
		if (wait_time)
		mdelay(wait_time);
		} while (wait_time);

		if (rc) {
		pr_err("Failed to invalidate firmware-assisted dump registration. Unexpected error (%d).\n", rc);
		return rc;
		}
		fw_dump.dump_active = 0;
		fdm_active = NULL;
		return 0;
		}

		void fadump_cleanup(void)
		{
		/* Invalidate the registration only if dump is active. */
		if (fw_dump.dump_active) {
		/* pass the same memory dump structure provided by platform */
		fadump_invalidate_dump(fdm_active);
		pr_debug("Invalidating firmware-assisted dump registration\n");
		fw_dump.ops->fadump_invalidate(&fw_dump);
		} else if (fw_dump.dump_registered) {
		/* Un-register Firmware-assisted dump if it was registered. */
		fw_dump.ops->fadump_unregister(&fw_dump);
		@@ -1333,7 +1081,7 @@ static ssize_t fadump_register_store(struct kobject *kobj,
		int ret = 0;
		int input = -1;

		if (!fw_dump.fadump_enabled \|\| fdm_active)
		if (!fw_dump.fadump_enabled \|\| fw_dump.dump_active)
		return -EPERM;

		if (kstrtoint(buf, 0, &input))
		@@ -1346,6 +1094,7 @@ static ssize_t fadump_register_store(struct kobject *kobj,
		if (fw_dump.dump_registered == 0) {
		goto unlock_out;
		}

		/* Un-register Firmware-assisted dump */
		pr_debug("Un-register firmware-assisted dump\n");
		fw_dump.ops->fadump_unregister(&fw_dump);
		@@ -1370,62 +1119,11 @@ static ssize_t fadump_register_store(struct kobject *kobj,

		static int fadump_region_show(struct seq_file m, void private)
		{
		const struct rtas_fadump_mem_struct *fdm_ptr;

		if (!fw_dump.fadump_enabled)
		return 0;

		mutex_lock(&fadump_mutex);
		if (fdm_active)
		fdm_ptr = fdm_active;
		else {
		mutex_unlock(&fadump_mutex);
		fw_dump.ops->fadump_region_show(&fw_dump, m);
		return 0;
		}

		seq_printf(m,
		"CPU : [%#016llx-%#016llx] %#llx bytes, "
		"Dumped: %#llx\n",
		be64_to_cpu(fdm_ptr->cpu_state_data.destination_address),
		be64_to_cpu(fdm_ptr->cpu_state_data.destination_address) +
		be64_to_cpu(fdm_ptr->cpu_state_data.source_len) - 1,
		be64_to_cpu(fdm_ptr->cpu_state_data.source_len),
		be64_to_cpu(fdm_ptr->cpu_state_data.bytes_dumped));
		seq_printf(m,
		"HPTE: [%#016llx-%#016llx] %#llx bytes, "
		"Dumped: %#llx\n",
		be64_to_cpu(fdm_ptr->hpte_region.destination_address),
		be64_to_cpu(fdm_ptr->hpte_region.destination_address) +
		be64_to_cpu(fdm_ptr->hpte_region.source_len) - 1,
		be64_to_cpu(fdm_ptr->hpte_region.source_len),
		be64_to_cpu(fdm_ptr->hpte_region.bytes_dumped));
		seq_printf(m,
		"DUMP: [%#016llx-%#016llx] %#llx bytes, "
		"Dumped: %#llx\n",
		be64_to_cpu(fdm_ptr->rmr_region.destination_address),
		be64_to_cpu(fdm_ptr->rmr_region.destination_address) +
		be64_to_cpu(fdm_ptr->rmr_region.source_len) - 1,
		be64_to_cpu(fdm_ptr->rmr_region.source_len),
		be64_to_cpu(fdm_ptr->rmr_region.bytes_dumped));

		if (!fdm_active \|\|
		(fw_dump.reserve_dump_area_start ==
		be64_to_cpu(fdm_ptr->cpu_state_data.destination_address)))
		goto out;

		/* 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,
		be64_to_cpu(fdm_ptr->cpu_state_data.destination_address) - 1,
		be64_to_cpu(fdm_ptr->cpu_state_data.destination_address) -
		fw_dump.reserve_dump_area_start,
		be64_to_cpu(fdm_ptr->cpu_state_data.destination_address) -
		fw_dump.reserve_dump_area_start);
		out:
		if (fdm_active)
		mutex_unlock(&fadump_mutex);
		return 0;
		}
		@@ -1497,12 +1195,13 @@ int __init setup_fadump(void)
		* if dump process fails then invalidate the registration
		* and release memory before proceeding for re-registration.
		*/
		if (process_fadump(fdm_active) < 0)
		if (fw_dump.ops->fadump_process(&fw_dump) < 0)
		fadump_invalidate_release_mem();
		}
		/* Initialize the kernel dump memory structure for FAD registration. */
		else if (fw_dump.reserve_dump_area_size)
		fw_dump.ops->fadump_init_mem_struct(&fw_dump);

		fadump_init_files();

		return 1;

arch/powerpc/platforms/pseries/rtas-fadump.c

+260 −3

Original line number	Diff line number	Diff line
		@@ -23,6 +23,7 @@
		#include "rtas-fadump.h"

		static struct rtas_fadump_mem_struct fdm;
		static const struct rtas_fadump_mem_struct *fdm_active;

		static void rtas_fadump_update_config(struct fw_dump *fadump_conf,
		const struct rtas_fadump_mem_struct *fdm)
		@@ -34,6 +35,25 @@ static void rtas_fadump_update_config(struct fw_dump *fadump_conf,
		fadump_conf->boot_memory_size);
		}

		/*
		* This function is called in the capture kernel to get configuration details
		* setup in the first kernel and passed to the f/w.
		*/
		static void rtas_fadump_get_config(struct fw_dump *fadump_conf,
		const struct rtas_fadump_mem_struct *fdm)
		{
		fadump_conf->boot_memory_size = be64_to_cpu(fdm->rmr_region.source_len);

		/*
		* Start address of reserve dump area (permanent reservation) for
		* re-registering FADump after dump capture.
		*/
		fadump_conf->reserve_dump_area_start =
		be64_to_cpu(fdm->cpu_state_data.destination_address);

		rtas_fadump_update_config(fadump_conf, fdm);
		}

		static u64 rtas_fadump_init_mem_struct(struct fw_dump *fadump_conf)
		{
		u64 addr = fadump_conf->reserve_dump_area_start;
		@@ -171,23 +191,243 @@ static int rtas_fadump_unregister(struct fw_dump *fadump_conf)

		static int rtas_fadump_invalidate(struct fw_dump *fadump_conf)
		{
		unsigned int wait_time;
		int rc;

		/* TODO: Add upper time limit for the delay */
		do {
		rc = rtas_call(fadump_conf->ibm_configure_kernel_dump, 3, 1,
		NULL, FADUMP_INVALIDATE, fdm_active,
		sizeof(struct rtas_fadump_mem_struct));

		wait_time = rtas_busy_delay_time(rc);
		if (wait_time)
		mdelay(wait_time);
		} while (wait_time);

		if (rc) {
		pr_err("Failed to invalidate - unexpected error (%d).\n", rc);
		return -EIO;
		}

		fadump_conf->dump_active = 0;
		fdm_active = NULL;
		return 0;
		}

		#define RTAS_FADUMP_GPR_MASK 0xffffff0000000000
		static inline int rtas_fadump_gpr_index(u64 id)
		{
		char str[3];
		int i = -1;

		if ((id & RTAS_FADUMP_GPR_MASK) == fadump_str_to_u64("GPR")) {
		/* get the digits at the end */
		id &= ~RTAS_FADUMP_GPR_MASK;
		id >>= 24;
		str[2] = '\0';
		str[1] = id & 0xff;
		str[0] = (id >> 8) & 0xff;
		if (kstrtoint(str, 10, &i))
		i = -EINVAL;
		if (i > 31)
		i = -1;
		}
		return i;
		}

		void rtas_fadump_set_regval(struct pt_regs *regs, u64 reg_id, u64 reg_val)
		{
		int i;

		i = rtas_fadump_gpr_index(reg_id);
		if (i >= 0)
		regs->gpr[i] = (unsigned long)reg_val;
		else if (reg_id == fadump_str_to_u64("NIA"))
		regs->nip = (unsigned long)reg_val;
		else if (reg_id == fadump_str_to_u64("MSR"))
		regs->msr = (unsigned long)reg_val;
		else if (reg_id == fadump_str_to_u64("CTR"))
		regs->ctr = (unsigned long)reg_val;
		else if (reg_id == fadump_str_to_u64("LR"))
		regs->link = (unsigned long)reg_val;
		else if (reg_id == fadump_str_to_u64("XER"))
		regs->xer = (unsigned long)reg_val;
		else if (reg_id == fadump_str_to_u64("CR"))
		regs->ccr = (unsigned long)reg_val;
		else if (reg_id == fadump_str_to_u64("DAR"))
		regs->dar = (unsigned long)reg_val;
		else if (reg_id == fadump_str_to_u64("DSISR"))
		regs->dsisr = (unsigned long)reg_val;
		}

		static struct rtas_fadump_reg_entry*
		rtas_fadump_read_regs(struct rtas_fadump_reg_entry *reg_entry,
		struct pt_regs *regs)
		{
		memset(regs, 0, sizeof(struct pt_regs));

		while (be64_to_cpu(reg_entry->reg_id) != fadump_str_to_u64("CPUEND")) {
		rtas_fadump_set_regval(regs, be64_to_cpu(reg_entry->reg_id),
		be64_to_cpu(reg_entry->reg_value));
		reg_entry++;
		}
		reg_entry++;
		return reg_entry;
		}

		/*
		* Read CPU state dump data and convert it into ELF notes.
		* The CPU dump starts with magic number "REGSAVE". NumCpusOffset should be
		* used to access the data to allow for additional fields to be added without
		* affecting compatibility. Each list of registers for a CPU starts with
		* "CPUSTRT" and ends with "CPUEND". Each register entry is of 16 bytes,
		* 8 Byte ASCII identifier and 8 Byte register value. The register entry
		* with identifier "CPUSTRT" and "CPUEND" contains 4 byte cpu id as part
		* of register value. For more details refer to PAPR document.
		*
		* Only for the crashing cpu we ignore the CPU dump data and get exact
		* state from fadump crash info structure populated by first kernel at the
		* time of crash.
		*/
		static int __init rtas_fadump_build_cpu_notes(struct fw_dump *fadump_conf)
		{
		struct rtas_fadump_reg_save_area_header *reg_header;
		struct fadump_crash_info_header *fdh = NULL;
		struct rtas_fadump_reg_entry *reg_entry;
		u32 num_cpus, *note_buf;
		int i, rc = 0, cpu = 0;
		struct pt_regs regs;
		unsigned long addr;
		void *vaddr;

		addr = be64_to_cpu(fdm_active->cpu_state_data.destination_address);
		vaddr = __va(addr);

		reg_header = vaddr;
		if (be64_to_cpu(reg_header->magic_number) !=
		fadump_str_to_u64("REGSAVE")) {
		pr_err("Unable to read register save area.\n");
		return -ENOENT;
		}

		pr_debug("--------CPU State Data------------\n");
		pr_debug("Magic Number: %llx\n", be64_to_cpu(reg_header->magic_number));
		pr_debug("NumCpuOffset: %x\n", be32_to_cpu(reg_header->num_cpu_offset));

		vaddr += be32_to_cpu(reg_header->num_cpu_offset);
		num_cpus = be32_to_cpu(((__be32 )(vaddr)));
		pr_debug("NumCpus : %u\n", num_cpus);
		vaddr += sizeof(u32);
		reg_entry = (struct rtas_fadump_reg_entry *)vaddr;

		rc = fadump_setup_cpu_notes_buf(num_cpus);
		if (rc != 0)
		return rc;

		note_buf = (u32 *)fadump_conf->cpu_notes_buf_vaddr;

		if (fadump_conf->fadumphdr_addr)
		fdh = __va(fadump_conf->fadumphdr_addr);

		for (i = 0; i < num_cpus; i++) {
		if (be64_to_cpu(reg_entry->reg_id) !=
		fadump_str_to_u64("CPUSTRT")) {
		pr_err("Unable to read CPU state data\n");
		rc = -ENOENT;
		goto error_out;
		}
		/* Lower 4 bytes of reg_value contains logical cpu id */
		cpu = (be64_to_cpu(reg_entry->reg_value) &
		RTAS_FADUMP_CPU_ID_MASK);
		if (fdh && !cpumask_test_cpu(cpu, &fdh->online_mask)) {
		RTAS_FADUMP_SKIP_TO_NEXT_CPU(reg_entry);
		continue;
		}
		pr_debug("Reading register data for cpu %d...\n", cpu);
		if (fdh && fdh->crashing_cpu == cpu) {
		regs = fdh->regs;
		note_buf = fadump_regs_to_elf_notes(note_buf, &regs);
		RTAS_FADUMP_SKIP_TO_NEXT_CPU(reg_entry);
		} else {
		reg_entry++;
		reg_entry = rtas_fadump_read_regs(reg_entry, &regs);
		note_buf = fadump_regs_to_elf_notes(note_buf, &regs);
		}
		}
		final_note(note_buf);

		if (fdh) {
		pr_debug("Updating elfcore header (%llx) with cpu notes\n",
		fdh->elfcorehdr_addr);
		fadump_update_elfcore_header(__va(fdh->elfcorehdr_addr));
		}
		return 0;

		error_out:
		fadump_free_cpu_notes_buf();
		return rc;

		}

		/*
		* Validate and process the dump data stored by firmware before exporting
		* it through '/proc/vmcore'.
		*/
		static int __init rtas_fadump_process(struct fw_dump *fadump_conf)
		{
		struct fadump_crash_info_header *fdh;
		int rc = 0;

		if (!fdm_active \|\| !fadump_conf->fadumphdr_addr)
		return -EINVAL;

		/* Check if the dump data is valid. */
		if ((be16_to_cpu(fdm_active->header.dump_status_flag) ==
		RTAS_FADUMP_ERROR_FLAG) \|\|
		(fdm_active->cpu_state_data.error_flags != 0) \|\|
		(fdm_active->rmr_region.error_flags != 0)) {
		pr_err("Dump taken by platform is not valid\n");
		return -EINVAL;
		}
		if ((fdm_active->rmr_region.bytes_dumped !=
		fdm_active->rmr_region.source_len) \|\|
		!fdm_active->cpu_state_data.bytes_dumped) {
		pr_err("Dump taken by platform is incomplete\n");
		return -EINVAL;
		}

		/* Validate the fadump crash info header */
		fdh = __va(fadump_conf->fadumphdr_addr);
		if (fdh->magic_number != FADUMP_CRASH_INFO_MAGIC) {
		pr_err("Crash info header is not valid.\n");
		return -EINVAL;
		}

		rc = rtas_fadump_build_cpu_notes(fadump_conf);
		if (rc)
		return rc;

		/*
		* We are done validating dump info and elfcore header is now ready
		* to be exported. set elfcorehdr_addr so that vmcore module will
		* export the elfcore header through '/proc/vmcore'.
		*/
		elfcorehdr_addr = fdh->elfcorehdr_addr;

		return 0;
		}

		static void rtas_fadump_region_show(struct fw_dump *fadump_conf,
		struct seq_file *m)
		{
		const struct rtas_fadump_mem_struct *fdm_ptr = &fdm;
		const struct rtas_fadump_section *cpu_data_section;
		const struct rtas_fadump_mem_struct *fdm_ptr;

		if (fdm_active)
		fdm_ptr = fdm_active;
		else
		fdm_ptr = &fdm;

		cpu_data_section = &(fdm_ptr->cpu_state_data);
		seq_printf(m, "CPU :[%#016llx-%#016llx] %#llx bytes, Dumped: %#llx\n",
		@@ -210,6 +450,12 @@ static void rtas_fadump_region_show(struct fw_dump *fadump_conf,
		seq_printf(m, "Size: %#llx, Dumped: %#llx bytes\n",
		be64_to_cpu(fdm_ptr->rmr_region.source_len),
		be64_to_cpu(fdm_ptr->rmr_region.bytes_dumped));

		/* Dump is active. Show reserved area start address. */
		if (fdm_active) {
		seq_printf(m, "\nMemory above %#016lx is reserved for saving crash dump\n",
		fadump_conf->reserve_dump_area_start);
		}
		}

		static void rtas_fadump_trigger(struct fadump_crash_info_header *fdh,
		@@ -247,6 +493,17 @@ void __init rtas_fadump_dt_scan(struct fw_dump *fadump_conf, u64 node)
		fadump_conf->ops = &rtas_fadump_ops;
		fadump_conf->fadump_supported = 1;

		/*
		* The 'ibm,kernel-dump' rtas node is present only if there is
		* dump data waiting for us.
		*/
		fdm_active = of_get_flat_dt_prop(node, "ibm,kernel-dump", NULL);
		if (fdm_active) {
		pr_info("Firmware-assisted dump is active.\n");
		fadump_conf->dump_active = 1;
		rtas_fadump_get_config(fadump_conf, (void *)__pa(fdm_active));
		}

		/* Get the sizes required to store dump data for the firmware provided
		* dump sections.
		* For each dump section type supported, a 32bit cell which defines