ACPICA: Hardware: Add sleep register hooks

ACPICA commit ba665dc8e20d9f7730466a659564dd6c557a6cbc

In Linux, para-virtualization implmentation hooks critical register
writes to prevent real hardware operations. This increases divergences
when the sleep registers are cracked in Linux resident ACPICA.

This patch tries to introduce a single OSL to reduce the divergences.

Link: https://github.com/acpica/acpica/commit/ba665dc8
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

6 files changed, 76 insertions, 32 deletions

diff --git a/drivers/acpi/acpica/hwesleep.c b/drivers/acpi/acpica/hwesleep.c
index 3f2fb4b31fdc..9023a1b87a54 100644
--- a/drivers/acpi/acpica/hwesleep.c
+++ b/drivers/acpi/acpica/hwesleep.c
@@ -43,7 +43,6 @@
  */
 
 #include <acpi/acpi.h>
-#include <linux/acpi.h>
 #include "accommon.h"
 
 #define _COMPONENT          ACPI_HARDWARE
@@ -103,7 +102,7 @@ void acpi_hw_execute_sleep_method(char *method_pathname, u32 integer_argument)
 acpi_status acpi_hw_extended_sleep(u8 sleep_state)
 {
         acpi_status status;
-        u8 sleep_type_value;
+        u8 sleep_control;
         u64 sleep_status;
 
         ACPI_FUNCTION_TRACE(hw_extended_sleep);
@@ -125,18 +124,6 @@ acpi_status acpi_hw_extended_sleep(u8 sleep_state)
 
         acpi_gbl_system_awake_and_running = FALSE;
 
-        /* Flush caches, as per ACPI specification */
-
-        ACPI_FLUSH_CPU_CACHE();
-
-        status = acpi_os_prepare_extended_sleep(sleep_state,
-                                                acpi_gbl_sleep_type_a,
-                                                acpi_gbl_sleep_type_b);
-        if (ACPI_SKIP(status))
-                return_ACPI_STATUS(AE_OK);
-        if (ACPI_FAILURE(status))
-                return_ACPI_STATUS(status);
-
         /*
          * Set the SLP_TYP and SLP_EN bits.
          *
@@ -146,12 +133,22 @@ acpi_status acpi_hw_extended_sleep(u8 sleep_state)
         ACPI_DEBUG_PRINT((ACPI_DB_INIT,
                           "Entering sleep state [S%u]\n", sleep_state));
 
-        sleep_type_value =
-            ((acpi_gbl_sleep_type_a << ACPI_X_SLEEP_TYPE_POSITION) &
-             ACPI_X_SLEEP_TYPE_MASK);
+        sleep_control = ((acpi_gbl_sleep_type_a << ACPI_X_SLEEP_TYPE_POSITION) &
+                         ACPI_X_SLEEP_TYPE_MASK) | ACPI_X_SLEEP_ENABLE;
+
+        /* Flush caches, as per ACPI specification */
+
+        ACPI_FLUSH_CPU_CACHE();
+
+        status = acpi_os_enter_sleep(sleep_state, sleep_control, 0);
+        if (status == AE_CTRL_TERMINATE) {
+                return_ACPI_STATUS(AE_OK);
+        }
+        if (ACPI_FAILURE(status)) {
+                return_ACPI_STATUS(status);
+        }
 
-        status = acpi_write((u64)(sleep_type_value | ACPI_X_SLEEP_ENABLE),
-                            &acpi_gbl_FADT.sleep_control);
+        status = acpi_write((u64)sleep_control, &acpi_gbl_FADT.sleep_control);
         if (ACPI_FAILURE(status)) {
                 return_ACPI_STATUS(status);
         }
diff --git a/drivers/acpi/acpica/hwsleep.c b/drivers/acpi/acpica/hwsleep.c
index d00c9810845b..563c5d91663f 100644
--- a/drivers/acpi/acpica/hwsleep.c
+++ b/drivers/acpi/acpica/hwsleep.c
@@ -43,7 +43,6 @@
  */
 
 #include <acpi/acpi.h>
-#include <linux/acpi.h>
 #include "accommon.h"
 
 #define _COMPONENT          ACPI_HARDWARE
@@ -152,12 +151,14 @@ acpi_status acpi_hw_legacy_sleep(u8 sleep_state)
 
         ACPI_FLUSH_CPU_CACHE();
 
-        status = acpi_os_prepare_sleep(sleep_state, pm1a_control,
-                                       pm1b_control);
-        if (ACPI_SKIP(status))
+        status = acpi_os_enter_sleep(sleep_state, pm1a_control, pm1b_control);
+        if (status == AE_CTRL_TERMINATE) {
                 return_ACPI_STATUS(AE_OK);
-        if (ACPI_FAILURE(status))
+        }
+        if (ACPI_FAILURE(status)) {
                 return_ACPI_STATUS(status);
+        }
+
         /* Write #2: Write both SLP_TYP + SLP_EN */
 
         status = acpi_hw_write_pm1_control(pm1a_control, pm1b_control);
diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index 57fb5f468ac2..db78d353bab1 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -1686,7 +1686,7 @@ acpi_status acpi_os_prepare_sleep(u8 sleep_state, u32 pm1a_control,
         if (rc < 0)
                 return AE_ERROR;
         else if (rc > 0)
-                return AE_CTRL_SKIP;
+                return AE_CTRL_TERMINATE;
 
         return AE_OK;
 }
@@ -1697,6 +1697,7 @@ void acpi_os_set_prepare_sleep(int (*func)(u8 sleep_state,
         __acpi_os_prepare_sleep = func;
 }
 
+#if (ACPI_REDUCED_HARDWARE)
 acpi_status acpi_os_prepare_extended_sleep(u8 sleep_state, u32 val_a,
                                   u32 val_b)
 {
@@ -1707,13 +1708,35 @@ acpi_status acpi_os_prepare_extended_sleep(u8 sleep_state, u32 val_a,
         if (rc < 0)
                 return AE_ERROR;
         else if (rc > 0)
-                return AE_CTRL_SKIP;
+                return AE_CTRL_TERMINATE;
 
         return AE_OK;
 }
+#else
+acpi_status acpi_os_prepare_extended_sleep(u8 sleep_state, u32 val_a,
+                                  u32 val_b)
+{
+        return AE_OK;
+}
+#endif
 
 void acpi_os_set_prepare_extended_sleep(int (*func)(u8 sleep_state,
                                u32 val_a, u32 val_b))
 {
         __acpi_os_prepare_extended_sleep = func;
 }
+
+acpi_status acpi_os_enter_sleep(u8 sleep_state,
+                                u32 reg_a_value, u32 reg_b_value)
+{
+        acpi_status status;
+
+        if (acpi_gbl_reduced_hardware)
+                status = acpi_os_prepare_extended_sleep(sleep_state,
+                                                        reg_a_value,
+                                                        reg_b_value);
+        else
+                status = acpi_os_prepare_sleep(sleep_state,
+                                               reg_a_value, reg_b_value);
+        return status;
+}
diff --git a/include/acpi/acexcep.h b/include/acpi/acexcep.h
index 2c396344a7a2..1155002761a7 100644
--- a/include/acpi/acexcep.h
+++ b/include/acpi/acexcep.h
@@ -91,7 +91,6 @@ struct acpi_exception_info {
 #define ACPI_SUCCESS(a)                 (!(a))
 #define ACPI_FAILURE(a)                 (a)
 
-#define ACPI_SKIP(a)                    (a == AE_CTRL_SKIP)
 #define AE_OK                           (acpi_status) 0x0000
 
 /*
@@ -211,11 +210,10 @@ struct acpi_exception_info {
 #define AE_CTRL_TRANSFER                EXCEP_CTL (0x0008)
 #define AE_CTRL_BREAK                   EXCEP_CTL (0x0009)
 #define AE_CTRL_CONTINUE                EXCEP_CTL (0x000A)
-#define AE_CTRL_SKIP                    EXCEP_CTL (0x000B)
-#define AE_CTRL_PARSE_CONTINUE          EXCEP_CTL (0x000C)
-#define AE_CTRL_PARSE_PENDING           EXCEP_CTL (0x000D)
+#define AE_CTRL_PARSE_CONTINUE          EXCEP_CTL (0x000B)
+#define AE_CTRL_PARSE_PENDING           EXCEP_CTL (0x000C)
 
-#define AE_CODE_CTRL_MAX                0x000D
+#define AE_CODE_CTRL_MAX                0x000C
 
 /* Exception strings for acpi_format_exception */
 
@@ -378,7 +376,6 @@ static const struct acpi_exception_info acpi_gbl_exception_names_ctrl[] = {
         EXCEP_TXT("AE_CTRL_TRANSFER", "Transfer control to called method"),
         EXCEP_TXT("AE_CTRL_BREAK", "A Break has been executed"),
         EXCEP_TXT("AE_CTRL_CONTINUE", "A Continue has been executed"),
-        EXCEP_TXT("AE_CTRL_SKIP", "Not currently used"),
         EXCEP_TXT("AE_CTRL_PARSE_CONTINUE", "Used to skip over bad opcodes"),
         EXCEP_TXT("AE_CTRL_PARSE_PENDING", "Used to implement AML While loops")
 };
diff --git a/include/acpi/acpiosxf.h b/include/acpi/acpiosxf.h
index 42ab9b37f33d..e166013b4712 100644
--- a/include/acpi/acpiosxf.h
+++ b/include/acpi/acpiosxf.h
@@ -333,6 +333,10 @@ u64 acpi_os_get_timer(void);
 acpi_status acpi_os_signal(u32 function, void *info);
 #endif
 
+#ifndef ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_enter_sleep
+acpi_status acpi_os_enter_sleep(u8 sleep_state, u32 rega_value, u32 regb_value);
+#endif
+
 /*
  * Debug print routines
  */
diff --git a/tools/power/acpi/os_specific/service_layers/osunixxf.c b/tools/power/acpi/os_specific/service_layers/osunixxf.c
index 10648aaf6164..e41c2644c347 100644
--- a/tools/power/acpi/os_specific/service_layers/osunixxf.c
+++ b/tools/power/acpi/os_specific/service_layers/osunixxf.c
@@ -318,6 +318,28 @@ acpi_os_physical_table_override(struct acpi_table_header *existing_table,
 
 /******************************************************************************
  *
+ * FUNCTION:    acpi_os_enter_sleep
+ *
+ * PARAMETERS:  sleep_state         - Which sleep state to enter
+ *              rega_value          - Register A value
+ *              regb_value          - Register B value
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: A hook before writing sleep registers to enter the sleep
+ *              state. Return AE_CTRL_TERMINATE to skip further sleep register
+ *              writes.
+ *
+ *****************************************************************************/
+
+acpi_status acpi_os_enter_sleep(u8 sleep_state, u32 rega_value, u32 regb_value)
+{
+
+        return (AE_OK);
+}
+
+/******************************************************************************
+ *
  * FUNCTION:    acpi_os_redirect_output
  *
  * PARAMETERS:  destination         - An open file handle/pointer