From 4f855dcead6c5be0a48a2779eeecb170ec144534 Mon Sep 17 00:00:00 2001 From: Kuppuswamy Sathyanarayanan Date: Wed, 22 Mar 2023 12:13:13 -0700 Subject: [PATCH] ACPI: sysfs: Enable ACPI sysfs support for CCEL records The Confidential Computing Event Log (CCEL) table provides the address and length of the CCEL records area in UEFI reserved memory. To allow user space access to these records, expose a sysfs interface similar to the BERT table. More details about the CCEL table can be found in the ACPI specification r6.5 [1], sec 5.2.34. Link: https://uefi.org/specs/ACPI/6.5/05_ACPI_Software_Programming_Model.html#cc-event-log-acpi-table # [1] Co-developed-by: Haibo Xu Signed-off-by: Haibo Xu Signed-off-by: Kuppuswamy Sathyanarayanan Signed-off-by: Rafael J. Wysocki --- drivers/acpi/sysfs.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/drivers/acpi/sysfs.c b/drivers/acpi/sysfs.c index 7f4ff56..687524b 100644 --- a/drivers/acpi/sysfs.c +++ b/drivers/acpi/sysfs.c @@ -458,11 +458,28 @@ static int acpi_bert_data_init(void *th, struct acpi_data_attr *data_attr) return sysfs_create_bin_file(tables_data_kobj, &data_attr->attr); } +static int acpi_ccel_data_init(void *th, struct acpi_data_attr *data_attr) +{ + struct acpi_table_ccel *ccel = th; + + if (ccel->header.length < sizeof(struct acpi_table_ccel) || + !ccel->log_area_start_address || !ccel->log_area_minimum_length) { + kfree(data_attr); + return -EINVAL; + } + data_attr->addr = ccel->log_area_start_address; + data_attr->attr.size = ccel->log_area_minimum_length; + data_attr->attr.attr.name = "CCEL"; + + return sysfs_create_bin_file(tables_data_kobj, &data_attr->attr); +} + static struct acpi_data_obj { char *name; int (*fn)(void *, struct acpi_data_attr *); } acpi_data_objs[] = { { ACPI_SIG_BERT, acpi_bert_data_init }, + { ACPI_SIG_CCEL, acpi_ccel_data_init }, }; #define NUM_ACPI_DATA_OBJS ARRAY_SIZE(acpi_data_objs) -- 2.7.4