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-rw-r--r--arch/powerpc/platforms/pseries/rtas-fadump.c557
1 files changed, 557 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/pseries/rtas-fadump.c b/arch/powerpc/platforms/pseries/rtas-fadump.c
new file mode 100644
index 000000000..b5853e9fc
--- /dev/null
+++ b/arch/powerpc/platforms/pseries/rtas-fadump.c
@@ -0,0 +1,557 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Firmware-Assisted Dump support on POWERVM platform.
+ *
+ * Copyright 2011, Mahesh Salgaonkar, IBM Corporation.
+ * Copyright 2019, Hari Bathini, IBM Corporation.
+ */
+
+#define pr_fmt(fmt) "rtas fadump: " fmt
+
+#include <linux/string.h>
+#include <linux/memblock.h>
+#include <linux/delay.h>
+#include <linux/seq_file.h>
+#include <linux/crash_dump.h>
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+
+#include <asm/page.h>
+#include <asm/rtas.h>
+#include <asm/fadump.h>
+#include <asm/fadump-internal.h>
+
+#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)
+{
+ fadump_conf->boot_mem_dest_addr =
+ be64_to_cpu(fdm->rmr_region.destination_address);
+
+ fadump_conf->fadumphdr_addr = (fadump_conf->boot_mem_dest_addr +
+ 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 __init rtas_fadump_get_config(struct fw_dump *fadump_conf,
+ const struct rtas_fadump_mem_struct *fdm)
+{
+ fadump_conf->boot_mem_addr[0] =
+ be64_to_cpu(fdm->rmr_region.source_address);
+ fadump_conf->boot_mem_sz[0] = be64_to_cpu(fdm->rmr_region.source_len);
+ fadump_conf->boot_memory_size = fadump_conf->boot_mem_sz[0];
+
+ fadump_conf->boot_mem_top = fadump_conf->boot_memory_size;
+ fadump_conf->boot_mem_regs_cnt = 1;
+
+ /*
+ * 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;
+
+ memset(&fdm, 0, sizeof(struct rtas_fadump_mem_struct));
+ addr = addr & PAGE_MASK;
+
+ fdm.header.dump_format_version = cpu_to_be32(0x00000001);
+ fdm.header.dump_num_sections = cpu_to_be16(3);
+ fdm.header.dump_status_flag = 0;
+ fdm.header.offset_first_dump_section =
+ cpu_to_be32((u32)offsetof(struct rtas_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 =
+ cpu_to_be32(RTAS_FADUMP_REQUEST_FLAG);
+ fdm.cpu_state_data.source_data_type =
+ cpu_to_be16(RTAS_FADUMP_CPU_STATE_DATA);
+ fdm.cpu_state_data.source_address = 0;
+ fdm.cpu_state_data.source_len =
+ cpu_to_be64(fadump_conf->cpu_state_data_size);
+ fdm.cpu_state_data.destination_address = cpu_to_be64(addr);
+ addr += fadump_conf->cpu_state_data_size;
+
+ /* hpte region section */
+ fdm.hpte_region.request_flag = cpu_to_be32(RTAS_FADUMP_REQUEST_FLAG);
+ fdm.hpte_region.source_data_type =
+ cpu_to_be16(RTAS_FADUMP_HPTE_REGION);
+ fdm.hpte_region.source_address = 0;
+ fdm.hpte_region.source_len =
+ cpu_to_be64(fadump_conf->hpte_region_size);
+ fdm.hpte_region.destination_address = cpu_to_be64(addr);
+ addr += fadump_conf->hpte_region_size;
+
+ /*
+ * Align boot memory area destination address to page boundary to
+ * be able to mmap read this area in the vmcore.
+ */
+ addr = PAGE_ALIGN(addr);
+
+ /* RMA region section */
+ fdm.rmr_region.request_flag = cpu_to_be32(RTAS_FADUMP_REQUEST_FLAG);
+ fdm.rmr_region.source_data_type =
+ cpu_to_be16(RTAS_FADUMP_REAL_MODE_REGION);
+ fdm.rmr_region.source_address = cpu_to_be64(0);
+ fdm.rmr_region.source_len = cpu_to_be64(fadump_conf->boot_memory_size);
+ fdm.rmr_region.destination_address = cpu_to_be64(addr);
+ addr += fadump_conf->boot_memory_size;
+
+ rtas_fadump_update_config(fadump_conf, &fdm);
+
+ return addr;
+}
+
+static u64 rtas_fadump_get_bootmem_min(void)
+{
+ return RTAS_FADUMP_MIN_BOOT_MEM;
+}
+
+static int rtas_fadump_register(struct fw_dump *fadump_conf)
+{
+ unsigned int wait_time;
+ int rc, err = -EIO;
+
+ /* TODO: Add upper time limit for the delay */
+ do {
+ rc = rtas_call(fadump_conf->ibm_configure_kernel_dump, 3, 1,
+ NULL, FADUMP_REGISTER, &fdm,
+ sizeof(struct rtas_fadump_mem_struct));
+
+ wait_time = rtas_busy_delay_time(rc);
+ if (wait_time)
+ mdelay(wait_time);
+
+ } while (wait_time);
+
+ switch (rc) {
+ case 0:
+ pr_info("Registration is successful!\n");
+ fadump_conf->dump_registered = 1;
+ err = 0;
+ break;
+ case -1:
+ pr_err("Failed to register. Hardware Error(%d).\n", rc);
+ break;
+ case -3:
+ if (!is_fadump_boot_mem_contiguous())
+ pr_err("Can't have holes in boot memory area.\n");
+ else if (!is_fadump_reserved_mem_contiguous())
+ pr_err("Can't have holes in reserved memory area.\n");
+
+ pr_err("Failed to register. Parameter Error(%d).\n", rc);
+ err = -EINVAL;
+ break;
+ case -9:
+ pr_err("Already registered!\n");
+ fadump_conf->dump_registered = 1;
+ err = -EEXIST;
+ break;
+ default:
+ pr_err("Failed to register. Unknown Error(%d).\n", rc);
+ break;
+ }
+
+ return err;
+}
+
+static int rtas_fadump_unregister(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_UNREGISTER, &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 un-register - unexpected error(%d).\n", rc);
+ return -EIO;
+ }
+
+ fadump_conf->dump_registered = 0;
+ return 0;
+}
+
+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;
+}
+
+static void __init 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* __init
+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->cpu_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_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",
+ be64_to_cpu(cpu_data_section->destination_address),
+ be64_to_cpu(cpu_data_section->destination_address) +
+ be64_to_cpu(cpu_data_section->source_len) - 1,
+ be64_to_cpu(cpu_data_section->source_len),
+ be64_to_cpu(cpu_data_section->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: Src: %#016llx, Dest: %#016llx, ",
+ be64_to_cpu(fdm_ptr->rmr_region.source_address),
+ be64_to_cpu(fdm_ptr->rmr_region.destination_address));
+ 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 preserved area start address. */
+ if (fdm_active) {
+ seq_printf(m, "\nMemory above %#016llx is reserved for saving crash dump\n",
+ fadump_conf->boot_mem_top);
+ }
+}
+
+static void rtas_fadump_trigger(struct fadump_crash_info_header *fdh,
+ const char *msg)
+{
+ /* Call ibm,os-term rtas call to trigger firmware assisted dump */
+ rtas_os_term((char *)msg);
+}
+
+static struct fadump_ops rtas_fadump_ops = {
+ .fadump_init_mem_struct = rtas_fadump_init_mem_struct,
+ .fadump_get_bootmem_min = rtas_fadump_get_bootmem_min,
+ .fadump_register = rtas_fadump_register,
+ .fadump_unregister = rtas_fadump_unregister,
+ .fadump_invalidate = rtas_fadump_invalidate,
+ .fadump_process = rtas_fadump_process,
+ .fadump_region_show = rtas_fadump_region_show,
+ .fadump_trigger = rtas_fadump_trigger,
+};
+
+void __init rtas_fadump_dt_scan(struct fw_dump *fadump_conf, u64 node)
+{
+ int i, size, num_sections;
+ const __be32 *sections;
+ const __be32 *token;
+
+ /*
+ * Check if Firmware Assisted dump is supported. if yes, check
+ * if dump has been initiated on last reboot.
+ */
+ token = of_get_flat_dt_prop(node, "ibm,configure-kernel-dump", NULL);
+ if (!token)
+ return;
+
+ fadump_conf->ibm_configure_kernel_dump = be32_to_cpu(*token);
+ fadump_conf->ops = &rtas_fadump_ops;
+ fadump_conf->fadump_supported = 1;
+
+ /* Firmware supports 64-bit value for size, align it to pagesize. */
+ fadump_conf->max_copy_size = ALIGN_DOWN(U64_MAX, PAGE_SIZE);
+
+ /*
+ * 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
+ * the ID of a supported section followed by two 32 bit cells which
+ * gives the size of the section in bytes.
+ */
+ sections = of_get_flat_dt_prop(node, "ibm,configure-kernel-dump-sizes",
+ &size);
+
+ if (!sections)
+ return;
+
+ num_sections = size / (3 * sizeof(u32));
+
+ for (i = 0; i < num_sections; i++, sections += 3) {
+ u32 type = (u32)of_read_number(sections, 1);
+
+ switch (type) {
+ case RTAS_FADUMP_CPU_STATE_DATA:
+ fadump_conf->cpu_state_data_size =
+ of_read_ulong(&sections[1], 2);
+ break;
+ case RTAS_FADUMP_HPTE_REGION:
+ fadump_conf->hpte_region_size =
+ of_read_ulong(&sections[1], 2);
+ break;
+ }
+ }
+}
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