Hi,
On 8/11/2023 1:48 AM, Avadhut Naik wrote:
> ACPI Platform Health Assessment Table (PHAT) enables a platform to expose
> an extensible set of platform health related telemetry. The telemetry is
> exposed through Firmware Version and Firmware Health Data Records which
> provide version data and health-related information of their associated
> components respectively.
>
> Additionally, the platform also provides Reset Reason Health Record in
> the PHAT table highlighting the cause of last system reset or boot in case
> of both expected and unexpected events. Vendor-specific data capturing the
> underlying state of the system during reset can also be optionally provided
> through the record.[1]
>
> Add support to parse the PHAT table during system bootup and have its
> information logged into the dmesg buffer.
>
> [1] ACPI specification 6.5, section 5.2.31.5
>
> Signed-off-by: Avadhut Naik <avadhut.naik@xxxxxxx>
> ---
> .../admin-guide/kernel-parameters.txt | 4 +
> drivers/acpi/Kconfig | 9 +
> drivers/acpi/Makefile | 1 +
> drivers/acpi/phat.c | 270 ++++++++++++++++++
> include/acpi/actbl2.h | 18 ++
> 5 files changed, 302 insertions(+)
> create mode 100644 drivers/acpi/phat.c
>
> diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
> index 722b6eca2e93..33b932302ece 100644
> --- a/Documentation/admin-guide/kernel-parameters.txt
> +++ b/Documentation/admin-guide/kernel-parameters.txt
> @@ -4490,6 +4490,10 @@
> allocator. This parameter is primarily for debugging
> and performance comparison.
>
> + phat_disable= [ACPI]
> + Disable PHAT table parsing and logging of Firmware
> + Version and Health Data records.
> +
> pirq= [SMP,APIC] Manual mp-table setup
> See Documentation/arch/x86/i386/IO-APIC.rst.
>
> diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
> index 00dd309b6682..06a7dd6e5a40 100644
> --- a/drivers/acpi/Kconfig
> +++ b/drivers/acpi/Kconfig
> @@ -96,6 +96,15 @@ config ACPI_FPDT
> This table provides information on the timing of the system
> boot, S3 suspend and S3 resume firmware code paths.
>
> +config ACPI_PHAT
> + bool "ACPI Platform Health Assessment Table (PHAT) support"
> + depends on X86_64 || ARM64
> + help
> + Enable support for Platform Health Assessment Table (PHAT).
> + This table exposes an extensible set of platform health
> + related telemetry through Firmware Version and Firmware Health
> + Data Records.
> +
> config ACPI_LPIT
> bool
> depends on X86_64
> diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
> index 3fc5a0d54f6e..93a4ec57ba6d 100644
> --- a/drivers/acpi/Makefile
> +++ b/drivers/acpi/Makefile
> @@ -69,6 +69,7 @@ acpi-$(CONFIG_ACPI_WATCHDOG) += acpi_watchdog.o
> acpi-$(CONFIG_ACPI_PRMT) += prmt.o
> acpi-$(CONFIG_ACPI_PCC) += acpi_pcc.o
> acpi-$(CONFIG_ACPI_FFH) += acpi_ffh.o
> +acpi-$(CONFIG_ACPI_PHAT) += phat.o
>
> # Address translation
> acpi-$(CONFIG_ACPI_ADXL) += acpi_adxl.o
> diff --git a/drivers/acpi/phat.c b/drivers/acpi/phat.c
> new file mode 100644
> index 000000000000..6006dd7615fa
> --- /dev/null
> +++ b/drivers/acpi/phat.c
> @@ -0,0 +1,270 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Platform Health Assessment Table (PHAT) support
> + *
> + * Copyright (C) 2023 Advanced Micro Devices, Inc.
> + *
> + * Author: Avadhut Naik <avadhut.naik@xxxxxxx>
> + *
> + * This file implements parsing of the Platform Health Assessment Table
> + * through which a platform can expose an extensible set of platform
> + * health related telemetry. The telemetry is exposed through Firmware
> + * Version Data Records and Firmware Health Data Records. Additionally,
> + * a platform, through system firmware, also exposes Reset Reason Health
> + * Record to inform the operating system of the cause of last system
> + * reset or boot.
> + *
> + * For more information on PHAT, please refer to ACPI specification
> + * version 6.5, section 5.2.31
> + */
> +
> +#include <linux/acpi.h>
> +
> +static int phat_disable __initdata;
> +static const char *prefix = "ACPI PHAT: ";
Wouldn't it be better if you used pr_fmt macro instead ?
> +
> +/* Reset Reason Health Record GUID */
> +static const guid_t reset_guid =
> + GUID_INIT(0x7a014ce2, 0xf263, 0x4b77,
> + 0xb8, 0x8a, 0xe6, 0x33, 0x6b, 0x78, 0x2c, 0x14);
> +
> +static struct { u8 mask; const char *str; } const reset_sources[] = {
> + {BIT(0), "Unknown source"},
> + {BIT(1), "Hardware Source"},
> + {BIT(2), "Firmware Source"},
> + {BIT(3), "Software initiated reset"},
> + {BIT(4), "Supervisor initiated reset"},
> +};
> +
> +static struct { u8 val; const char *str; } const reset_reasons[] = {
> + {0, "UNKNOWN"},
> + {1, "COLD BOOT"},
> + {2, "COLD RESET"},
> + {3, "WARM RESET"},
> + {4, "UPDATE"},
> + {32, "UNEXPECTED RESET"},
> + {33, "FAULT"},
> + {34, "TIMEOUT"},
> + {35, "THERMAL"},
> + {36, "POWER LOSS"},
> + {37, "POWER BUTTON"},
> +};
> +
> +/*
> + * Print the last PHAT Version Element associated with a Firmware
> + * Version Data Record.
> + * Firmware Version Data Record consists of an array of PHAT Version
> + * Elements with each entry in the array representing a modification
> + * undertaken on a given platform component.
> + * In the event the array has multiple entries, minimize logs on the
> + * console and print only the last version element since it denotes
> + * the currently running instance of the component.
> + */
> +static int phat_version_data_parse(const char *pfx,
> + struct acpi_phat_version_data *version)
> +{
> + char newpfx[64];
> + u32 num_elems = version->element_count - 1;
> + struct acpi_phat_version_element *element;
> + int offset = sizeof(struct acpi_phat_version_data);
> +
> + if (!version->element_count) {
> + pr_info("%sNo PHAT Version Elements found.\n", prefix);
> + return 0;
> + }
> +
> + offset += num_elems * sizeof(struct acpi_phat_version_element);
> + element = (void *)version + offset;
> +
> + pr_info("%sPHAT Version Element:\n", pfx);
> + snprintf(newpfx, sizeof(newpfx), "%s ", pfx);
> + pr_info("%sComponent ID: %pUl\n", newpfx, element->guid);
> + pr_info("%sVersion: 0x%llx\n", newpfx, element->version_value);
> + snprintf(newpfx, sizeof(newpfx), KERN_INFO "%s ", pfx);
> + print_hex_dump(newpfx, "Producer ID: ", DUMP_PREFIX_NONE, 16, 4,
> + &element->producer_id, sizeof(element->producer_id), true);
I do have to admit that all this dancing with pfx and newpfx confuses me. Couldn't you
just use pr_fmt for everything printed using pr_* family of functions ? print_hex_dump()
is not impacted by pr_fmt, as it just uses printk to do it's printing.
> +
> + return 0;
> +}
> +
> +/*
> + * Print the Reset Reason Health Record
> + */
> +static int phat_reset_reason_parse(const char *pfx,
> + struct acpi_phat_health_data *record)
> +{
> + int idx;
> + void *data;
> + u32 data_len;
> + char newpfx[64];
> + struct acpi_phat_reset_reason *rr;
> + struct acpi_phat_vendor_reset_data *vdata;
> +
> + rr = (void *)record + record->device_specific_offset;
> +
> + for (idx = 0; idx < ARRAY_SIZE(reset_sources); idx++) {
> + if (!rr->reset_source) {
> + pr_info("%sUnknown Reset Source.\n", pfx);
> + break;
> + }
> + if (rr->reset_source & reset_sources[idx].mask) {
> + pr_info("%sReset Source: 0x%x\t%s\n", pfx, reset_sources[idx].mask,
> + reset_sources[idx].str);
> + /* According to ACPI v6.5 Table 5.168, Sub-Source is
> + * defined only for Software initiated reset.
> + */
> + if (idx == 0x3 && rr->reset_sub_source)
> + pr_info("%sReset Sub-Source: %s\n", pfx,
> + rr->reset_sub_source == 0x1 ?
> + "Operating System" : "Hypervisor");
> + break;
> + }
> + }
> +
> + for (idx = 0; idx < ARRAY_SIZE(reset_reasons); idx++) {
> + if (rr->reset_reason == reset_reasons[idx].val) {
> + pr_info("%sReset Reason: 0x%x\t%s\n", pfx, reset_reasons[idx].val,
> + reset_reasons[idx].str);
> + break;
> + }
> + }
> +
> + if (!rr->vendor_count)
> + return 0;
> +
> + pr_info("%sReset Reason Vendor Data:\n", pfx);
> + vdata = (void *)rr + sizeof(*rr);
> +
> + for (idx = 0; idx < rr->vendor_count; idx++) {
> + snprintf(newpfx, sizeof(newpfx), "%s ", pfx);
> + data_len = vdata->length - sizeof(*vdata);
> + data = (void *)vdata + sizeof(*vdata);
> + pr_info("%sVendor Data ID: %pUl\n", newpfx, vdata->vendor_id);
> + pr_info("%sRevision: 0x%x\n", newpfx, vdata->revision);
> + snprintf(newpfx, sizeof(newpfx), KERN_INFO "%s ", pfx);
> + print_hex_dump(newpfx, "Data: ", DUMP_PREFIX_NONE, 16, 4,
> + data, data_len, false);
> + vdata = (void *)vdata + vdata->length;
> + }
> +
> + return 0;
> +}
> +
> +/*
> + * Print the Firmware Health Data Record.
> + */
> +static int phat_health_data_parse(const char *pfx,
> + struct acpi_phat_health_data *record)
> +{
> + void *data;
> + u32 data_len;
> + char newpfx[64];
> +
> + pr_info("%sHealth Records.\n", pfx);
> + snprintf(newpfx, sizeof(newpfx), "%s ", pfx);
> + pr_info("%sDevice Signature: %pUl\n", newpfx, record->device_guid);
> +
> + switch (record->health) {
> + case ACPI_PHAT_ERRORS_FOUND:
> + pr_info("%sAmHealthy: Errors found\n", newpfx);
> + break;
> + case ACPI_PHAT_NO_ERRORS:
> + pr_info("%sAmHealthy: No errors found.\n", newpfx);
> + break;
> + case ACPI_PHAT_UNKNOWN_ERRORS:
> + pr_info("%sAmHealthy: Unknown.\n", newpfx);
> + break;
> + case ACPI_PHAT_ADVISORY:
> + pr_info("%sAmHealthy: Advisory – additional device-specific data exposed.\n",
> + newpfx);
> + break;
> + default:
> + break;
> + }
> +
> + if (!record->device_specific_offset)
> + return 0;
> +
> + /* Reset Reason Health Record has a unique GUID and is created as
> + * a Health Record in the PHAT table. Check if this Health Record
> + * is a Reset Reason Health Record.
> + */
> + if (guid_equal((guid_t *)record->device_guid, &reset_guid)) {
> + phat_reset_reason_parse(newpfx, record);
> + return 0;
> + }
> +
> + data = (void *)record + record->device_specific_offset;
> + data_len = record->header.length - record->device_specific_offset;
> + snprintf(newpfx, sizeof(newpfx), KERN_INFO "%s ", pfx);
> + print_hex_dump(newpfx, "Device Data: ", DUMP_PREFIX_NONE, 16, 4,
> + data, data_len, false);
> +
> + return 0;
> +}
> +
> +static int parse_phat_table(const char *pfx, struct acpi_table_phat *phat_tab)
> +{
> + char newpfx[64];
> + u32 offset = sizeof(*phat_tab);
> + struct acpi_phat_header *phat_header;
> +
> + snprintf(newpfx, sizeof(newpfx), "%s ", pfx);
> +
> + while (offset < phat_tab->header.length) {
> + phat_header = (void *)phat_tab + offset;
> + switch (phat_header->type) {
> + case ACPI_PHAT_TYPE_FW_VERSION_DATA:
> + phat_version_data_parse(newpfx, (struct acpi_phat_version_data *)
> + phat_header);
> + break;
> + case ACPI_PHAT_TYPE_FW_HEALTH_DATA:
> + phat_health_data_parse(newpfx, (struct acpi_phat_health_data *)
> + phat_header);
> + break;
> + default:
> + break;
> + }
> + offset += phat_header->length;
> + }
> + return 0;
> +}
> +
> +static int __init setup_phat_disable(char *str)
> +{
> + phat_disable = 1;
> + return 1;
> +}
> +__setup("phat_disable", setup_phat_disable);
> +
> +static int __init acpi_phat_init(void)
> +{
> + acpi_status status;
> + struct acpi_table_phat *phat_tab;
> +
> + if (acpi_disabled)
> + return 0;
> +
> + if (phat_disable) {
> + pr_err("%sPHAT support has been disabled.\n", prefix);
> + return 0;
> + }
> +
> + status = acpi_get_table(ACPI_SIG_PHAT, 0,
> + (struct acpi_table_header **)&phat_tab);
> +
> + if (status == AE_NOT_FOUND) {
> + pr_info("%sPHAT Table not found.\n", prefix);
> + return 0;
> + } else if (ACPI_FAILURE(status)) {
> + pr_err("%sFailed to get PHAT Table: %s.\n", prefix,
> + acpi_format_exception(status));
> + return -EINVAL;
> + }
> +
> + pr_info("%sPlatform Telemetry Records.\n", prefix);
> + parse_phat_table(prefix, phat_tab);
So for now you're only dumping tables to the dmesg output ?
Are you planning to create some sysfs interfaces similar to let's
say EINJ ?
> +
> + return 0;
> +}
> +late_initcall(acpi_phat_init);
> diff --git a/include/acpi/actbl2.h b/include/acpi/actbl2.h
> index 0029336775a9..c263893cbc7f 100644
> --- a/include/acpi/actbl2.h
> +++ b/include/acpi/actbl2.h
> @@ -2360,6 +2360,24 @@ struct acpi_phat_health_data {
> #define ACPI_PHAT_UNKNOWN_ERRORS 2
> #define ACPI_PHAT_ADVISORY 3
>
> +/* Reset Reason Health Record Structure */
> +
> +struct acpi_phat_reset_reason {
> + u8 supported_reset_sources;
> + u8 reset_source;
> + u8 reset_sub_source;
> + u8 reset_reason;
> + u16 vendor_count;
> +};
> +
> +/* Reset Reason Health Record Vendor Data Entry */
> +
> +struct acpi_phat_vendor_reset_data {
> + u8 vendor_id[16];
> + u16 length;
> + u16 revision;
> +};
> +
> /*******************************************************************************
> *
> * PMTT - Platform Memory Topology Table (ACPI 5.0)
