v4.19.13 snapshot.
diff --git a/drivers/acpi/acpica/dbhistry.c b/drivers/acpi/acpica/dbhistry.c
new file mode 100644
index 0000000..b0b9a26
--- /dev/null
+++ b/drivers/acpi/acpica/dbhistry.c
@@ -0,0 +1,205 @@
+// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
+/******************************************************************************
+ *
+ * Module Name: dbhistry - debugger HISTORY command
+ *
+ * Copyright (C) 2000 - 2018, Intel Corp.
+ *
+ *****************************************************************************/
+
+#include <acpi/acpi.h>
+#include "accommon.h"
+#include "acdebug.h"
+
+#define _COMPONENT ACPI_CA_DEBUGGER
+ACPI_MODULE_NAME("dbhistry")
+
+#define HI_NO_HISTORY 0
+#define HI_RECORD_HISTORY 1
+#define HISTORY_SIZE 40
+typedef struct history_info {
+ char *command;
+ u32 cmd_num;
+
+} HISTORY_INFO;
+
+static HISTORY_INFO acpi_gbl_history_buffer[HISTORY_SIZE];
+static u16 acpi_gbl_lo_history = 0;
+static u16 acpi_gbl_num_history = 0;
+static u16 acpi_gbl_next_history_index = 0;
+u32 acpi_gbl_next_cmd_num = 1;
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_db_add_to_history
+ *
+ * PARAMETERS: command_line - Command to add
+ *
+ * RETURN: None
+ *
+ * DESCRIPTION: Add a command line to the history buffer.
+ *
+ ******************************************************************************/
+
+void acpi_db_add_to_history(char *command_line)
+{
+ u16 cmd_len;
+ u16 buffer_len;
+
+ /* Put command into the next available slot */
+
+ cmd_len = (u16)strlen(command_line);
+ if (!cmd_len) {
+ return;
+ }
+
+ if (acpi_gbl_history_buffer[acpi_gbl_next_history_index].command !=
+ NULL) {
+ buffer_len =
+ (u16)
+ strlen(acpi_gbl_history_buffer[acpi_gbl_next_history_index].
+ command);
+
+ if (cmd_len > buffer_len) {
+ acpi_os_free(acpi_gbl_history_buffer
+ [acpi_gbl_next_history_index].command);
+ acpi_gbl_history_buffer[acpi_gbl_next_history_index].
+ command = acpi_os_allocate(cmd_len + 1);
+ }
+ } else {
+ acpi_gbl_history_buffer[acpi_gbl_next_history_index].command =
+ acpi_os_allocate(cmd_len + 1);
+ }
+
+ strcpy(acpi_gbl_history_buffer[acpi_gbl_next_history_index].command,
+ command_line);
+
+ acpi_gbl_history_buffer[acpi_gbl_next_history_index].cmd_num =
+ acpi_gbl_next_cmd_num;
+
+ /* Adjust indexes */
+
+ if ((acpi_gbl_num_history == HISTORY_SIZE) &&
+ (acpi_gbl_next_history_index == acpi_gbl_lo_history)) {
+ acpi_gbl_lo_history++;
+ if (acpi_gbl_lo_history >= HISTORY_SIZE) {
+ acpi_gbl_lo_history = 0;
+ }
+ }
+
+ acpi_gbl_next_history_index++;
+ if (acpi_gbl_next_history_index >= HISTORY_SIZE) {
+ acpi_gbl_next_history_index = 0;
+ }
+
+ acpi_gbl_next_cmd_num++;
+ if (acpi_gbl_num_history < HISTORY_SIZE) {
+ acpi_gbl_num_history++;
+ }
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_db_display_history
+ *
+ * PARAMETERS: None
+ *
+ * RETURN: None
+ *
+ * DESCRIPTION: Display the contents of the history buffer
+ *
+ ******************************************************************************/
+
+void acpi_db_display_history(void)
+{
+ u32 i;
+ u16 history_index;
+
+ history_index = acpi_gbl_lo_history;
+
+ /* Dump entire history buffer */
+
+ for (i = 0; i < acpi_gbl_num_history; i++) {
+ if (acpi_gbl_history_buffer[history_index].command) {
+ acpi_os_printf("%3ld %s\n",
+ acpi_gbl_history_buffer[history_index].
+ cmd_num,
+ acpi_gbl_history_buffer[history_index].
+ command);
+ }
+
+ history_index++;
+ if (history_index >= HISTORY_SIZE) {
+ history_index = 0;
+ }
+ }
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_db_get_from_history
+ *
+ * PARAMETERS: command_num_arg - String containing the number of the
+ * command to be retrieved
+ *
+ * RETURN: Pointer to the retrieved command. Null on error.
+ *
+ * DESCRIPTION: Get a command from the history buffer
+ *
+ ******************************************************************************/
+
+char *acpi_db_get_from_history(char *command_num_arg)
+{
+ u32 cmd_num;
+
+ if (command_num_arg == NULL) {
+ cmd_num = acpi_gbl_next_cmd_num - 1;
+ }
+
+ else {
+ cmd_num = strtoul(command_num_arg, NULL, 0);
+ }
+
+ return (acpi_db_get_history_by_index(cmd_num));
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_db_get_history_by_index
+ *
+ * PARAMETERS: cmd_num - Index of the desired history entry.
+ * Values are 0...(acpi_gbl_next_cmd_num - 1)
+ *
+ * RETURN: Pointer to the retrieved command. Null on error.
+ *
+ * DESCRIPTION: Get a command from the history buffer
+ *
+ ******************************************************************************/
+
+char *acpi_db_get_history_by_index(u32 cmd_num)
+{
+ u32 i;
+ u16 history_index;
+
+ /* Search history buffer */
+
+ history_index = acpi_gbl_lo_history;
+ for (i = 0; i < acpi_gbl_num_history; i++) {
+ if (acpi_gbl_history_buffer[history_index].cmd_num == cmd_num) {
+
+ /* Found the command, return it */
+
+ return (acpi_gbl_history_buffer[history_index].command);
+ }
+
+ /* History buffer is circular */
+
+ history_index++;
+ if (history_index >= HISTORY_SIZE) {
+ history_index = 0;
+ }
+ }
+
+ acpi_os_printf("Invalid history number: %u\n", history_index);
+ return (NULL);
+}