From 63e8f906e94e122ad1a38588b919a6b5e98b3532 Mon Sep 17 00:00:00 2001 From: Jorge Lopez Date: Thu, 8 Jun 2023 11:33:17 -0500 Subject: [PATCH] platform/x86: hp-bioscfg: surestart-attributes MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Add Sure Start attributes support to hp-bioscfg. HP BIOS Configuration driver purpose is to provide a driver supporting the latest sysfs class firmware attributes framework allowing the user to change BIOS settings and security solutions on HP Inc.’s commercial notebooks. Signed-off-by: Jorge Lopez Reviewed-by: Thomas Weißschuh Link: https://lore.kernel.org/r/20230608163319.18934-12-jorge.lopez2@hp.com Signed-off-by: Hans de Goede --- .../x86/hp/hp-bioscfg/surestart-attributes.c | 132 +++++++++++++++++++++ 1 file changed, 132 insertions(+) create mode 100644 drivers/platform/x86/hp/hp-bioscfg/surestart-attributes.c diff --git a/drivers/platform/x86/hp/hp-bioscfg/surestart-attributes.c b/drivers/platform/x86/hp/hp-bioscfg/surestart-attributes.c new file mode 100644 index 0000000..b57e42f --- /dev/null +++ b/drivers/platform/x86/hp/hp-bioscfg/surestart-attributes.c @@ -0,0 +1,132 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Functions corresponding to sure start object type attributes under + * BIOS for use with hp-bioscfg driver + * + * Copyright (c) 2022 HP Development Company, L.P. + */ + +#include "bioscfg.h" +#include + +/* Maximum number of log entries supported when log entry size is 16 + * bytes. This value is calculated by dividing 4096 (page size) by + * log entry size. + */ +#define LOG_MAX_ENTRIES 254 + +/* + * Current Log entry size. This value size will change in the + * future. The driver reads a total of 128 bytes for each log entry + * provided by BIOS but only the first 16 bytes are used/read. + */ +#define LOG_ENTRY_SIZE 16 + +/* + * audit_log_entry_count_show - Reports the number of + * existing audit log entries available + * to be read + */ +static ssize_t audit_log_entry_count_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + int ret; + u32 count = 0; + + ret = hp_wmi_perform_query(HPWMI_SURESTART_GET_LOG_COUNT, + HPWMI_SURESTART, + &count, 1, sizeof(count)); + + if (ret < 0) + return ret; + + return sysfs_emit(buf, "%d,%d,%d\n", count, LOG_ENTRY_SIZE, + LOG_MAX_ENTRIES); +} + +/* + * audit_log_entries_show() - Return all entries found in log file + */ +static ssize_t audit_log_entries_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + int ret; + int i; + u32 count = 0; + u8 audit_log_buffer[128]; + + // Get the number of event logs + ret = hp_wmi_perform_query(HPWMI_SURESTART_GET_LOG_COUNT, + HPWMI_SURESTART, + &count, 1, sizeof(count)); + + if (ret < 0) + return ret; + + /* + * The show() api will not work if the audit logs ever go + * beyond 4KB + */ + if (count * LOG_ENTRY_SIZE > PAGE_SIZE) + return -EIO; + + /* + * We are guaranteed the buffer is 4KB so today all the event + * logs will fit + */ + for (i = 0; i < count; i++) { + audit_log_buffer[0] = i + 1; + + /* + * read audit log entry at a time. 'buf' input value + * provides the audit log entry to be read. On + * input, Byte 0 = Audit Log entry number from + * beginning (1..254) + * Entry number 1 is the newest entry whereas the + * highest entry number (number of entries) is the + * oldest entry. + */ + ret = hp_wmi_perform_query(HPWMI_SURESTART_GET_LOG, + HPWMI_SURESTART, + audit_log_buffer, 1, 128); + + if (ret < 0 || (LOG_ENTRY_SIZE * i) > PAGE_SIZE) { + /* + * Encountered a failure while reading + * individual logs. Only a partial list of + * audit log will be returned. + */ + break; + } else { + memcpy(buf, audit_log_buffer, LOG_ENTRY_SIZE); + buf += LOG_ENTRY_SIZE; + } + } + + return i * LOG_ENTRY_SIZE; +} + +static struct kobj_attribute sure_start_audit_log_entry_count = __ATTR_RO(audit_log_entry_count); +static struct kobj_attribute sure_start_audit_log_entries = __ATTR_RO(audit_log_entries); + +static struct attribute *sure_start_attrs[] = { + &sure_start_audit_log_entry_count.attr, + &sure_start_audit_log_entries.attr, + NULL +}; + +static const struct attribute_group sure_start_attr_group = { + .attrs = sure_start_attrs, +}; + +void hp_exit_sure_start_attributes(void) +{ + sysfs_remove_group(bioscfg_drv.sure_start_attr_kobj, + &sure_start_attr_group); +} + +int hp_populate_sure_start_data(struct kobject *attr_name_kobj) +{ + bioscfg_drv.sure_start_attr_kobj = attr_name_kobj; + return sysfs_create_group(attr_name_kobj, &sure_start_attr_group); +} -- 2.7.4