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 <jorge.lopez2@xxxxxx>
---
Based on the latest platform-drivers-x86.git/for-next
---
.../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 000000000000..b57e42f29282
--- /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 <linux/types.h>
+
+/* 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);
+}
--
2.34.1
