[PATCH 09/50] ACPI 5.0: Implement hardware-reduced option
From: Len Brown
Date: Tue Jan 17 2012 - 07:29:02 EST
From: Bob Moore <robert.moore@xxxxxxxxx>
If HW-reduced flag is set in the FADT, do not attempt to access
or initialize any ACPI hardware, including SCI and global lock.
No FACS will be present.
Signed-off-by: Bob Moore <robert.moore@xxxxxxxxx>
Signed-off-by: Lin Ming <ming.m.lin@xxxxxxxxx>
Signed-off-by: Len Brown <len.brown@xxxxxxxxx>
---
drivers/acpi/acpica/acglobal.h | 13 ++++++++++++-
drivers/acpi/acpica/evevent.c | 12 ++++++++++++
drivers/acpi/acpica/evglock.c | 6 ++++++
drivers/acpi/acpica/tbfadt.c | 22 ++++++++++++++++++++--
drivers/acpi/acpica/tbutils.c | 7 +++++++
include/acpi/acpixf.h | 1 +
6 files changed, 58 insertions(+), 3 deletions(-)
diff --git a/drivers/acpi/acpica/acglobal.h b/drivers/acpi/acpica/acglobal.h
index 76dc02f..25912a9 100644
--- a/drivers/acpi/acpica/acglobal.h
+++ b/drivers/acpi/acpica/acglobal.h
@@ -140,8 +140,19 @@ u32 acpi_gbl_trace_flags;
acpi_name acpi_gbl_trace_method_name;
u8 acpi_gbl_system_awake_and_running;
+/*
+ * ACPI 5.0 introduces the concept of a "reduced hardware platform", meaning
+ * that the ACPI hardware is no longer required. A flag in the FADT indicates
+ * a reduced HW machine, and that flag is duplicated here for convenience.
+ */
+u8 acpi_gbl_reduced_hardware;
+
#endif
+/* Do not disassemble buffers to resource descriptors */
+
+ACPI_EXTERN u8 ACPI_INIT_GLOBAL(acpi_gbl_no_resource_disassembly, FALSE);
+
/*****************************************************************************
*
* Debug support
@@ -207,7 +218,7 @@ ACPI_EXTERN struct acpi_rw_lock acpi_gbl_namespace_rw_lock;
/*****************************************************************************
*
- * Mutual exlusion within ACPICA subsystem
+ * Mutual exclusion within ACPICA subsystem
*
****************************************************************************/
diff --git a/drivers/acpi/acpica/evevent.c b/drivers/acpi/acpica/evevent.c
index d458b04..1f43be4 100644
--- a/drivers/acpi/acpica/evevent.c
+++ b/drivers/acpi/acpica/evevent.c
@@ -71,6 +71,12 @@ acpi_status acpi_ev_initialize_events(void)
ACPI_FUNCTION_TRACE(ev_initialize_events);
+ /* If Hardware Reduced flag is set, there are no fixed events */
+
+ if (acpi_gbl_reduced_hardware) {
+ return_ACPI_STATUS(AE_OK);
+ }
+
/*
* Initialize the Fixed and General Purpose Events. This is done prior to
* enabling SCIs to prevent interrupts from occurring before the handlers
@@ -111,6 +117,12 @@ acpi_status acpi_ev_install_xrupt_handlers(void)
ACPI_FUNCTION_TRACE(ev_install_xrupt_handlers);
+ /* If Hardware Reduced flag is set, there is no ACPI h/w */
+
+ if (acpi_gbl_reduced_hardware) {
+ return_ACPI_STATUS(AE_OK);
+ }
+
/* Install the SCI handler */
status = acpi_ev_install_sci_handler();
diff --git a/drivers/acpi/acpica/evglock.c b/drivers/acpi/acpica/evglock.c
index 56a562a..af1e71a 100644
--- a/drivers/acpi/acpica/evglock.c
+++ b/drivers/acpi/acpica/evglock.c
@@ -70,6 +70,12 @@ acpi_status acpi_ev_init_global_lock_handler(void)
ACPI_FUNCTION_TRACE(ev_init_global_lock_handler);
+ /* If Hardware Reduced flag is set, there is no global lock */
+
+ if (acpi_gbl_reduced_hardware) {
+ return_ACPI_STATUS(AE_OK);
+ }
+
/* Attempt installation of the global lock handler */
status = acpi_install_fixed_event_handler(ACPI_EVENT_GLOBAL,
diff --git a/drivers/acpi/acpica/tbfadt.c b/drivers/acpi/acpica/tbfadt.c
index 536fd2b..1e1a7de 100644
--- a/drivers/acpi/acpica/tbfadt.c
+++ b/drivers/acpi/acpica/tbfadt.c
@@ -253,8 +253,13 @@ void acpi_tb_parse_fadt(u32 table_index)
acpi_tb_install_table((acpi_physical_address) acpi_gbl_FADT.Xdsdt,
ACPI_SIG_DSDT, ACPI_TABLE_INDEX_DSDT);
- acpi_tb_install_table((acpi_physical_address) acpi_gbl_FADT.Xfacs,
- ACPI_SIG_FACS, ACPI_TABLE_INDEX_FACS);
+ /* If Hardware Reduced flag is set, there is no FACS */
+
+ if (!acpi_gbl_reduced_hardware) {
+ acpi_tb_install_table((acpi_physical_address) acpi_gbl_FADT.
+ Xfacs, ACPI_SIG_FACS,
+ ACPI_TABLE_INDEX_FACS);
+ }
}
/*******************************************************************************
@@ -297,6 +302,13 @@ void acpi_tb_create_local_fadt(struct acpi_table_header *table, u32 length)
ACPI_MEMCPY(&acpi_gbl_FADT, table,
ACPI_MIN(length, sizeof(struct acpi_table_fadt)));
+ /* Take a copy of the Hardware Reduced flag */
+
+ acpi_gbl_reduced_hardware = FALSE;
+ if (acpi_gbl_FADT.flags & ACPI_FADT_HW_REDUCED) {
+ acpi_gbl_reduced_hardware = TRUE;
+ }
+
/* Convert the local copy of the FADT to the common internal format */
acpi_tb_convert_fadt();
@@ -502,6 +514,12 @@ static void acpi_tb_validate_fadt(void)
acpi_gbl_FADT.Xdsdt = (u64) acpi_gbl_FADT.dsdt;
}
+ /* If Hardware Reduced flag is set, we are all done */
+
+ if (acpi_gbl_reduced_hardware) {
+ return;
+ }
+
/* Examine all of the 64-bit extended address fields (X fields) */
for (i = 0; i < ACPI_FADT_INFO_ENTRIES; i++) {
diff --git a/drivers/acpi/acpica/tbutils.c b/drivers/acpi/acpica/tbutils.c
index 0f2d395..da56a19 100644
--- a/drivers/acpi/acpica/tbutils.c
+++ b/drivers/acpi/acpica/tbutils.c
@@ -135,6 +135,13 @@ acpi_status acpi_tb_initialize_facs(void)
{
acpi_status status;
+ /* If Hardware Reduced flag is set, there is no FACS */
+
+ if (acpi_gbl_reduced_hardware) {
+ acpi_gbl_FACS = NULL;
+ return (AE_OK);
+ }
+
status = acpi_get_table_by_index(ACPI_TABLE_INDEX_FACS,
ACPI_CAST_INDIRECT_PTR(struct
acpi_table_header,
diff --git a/include/acpi/acpixf.h b/include/acpi/acpixf.h
index f554a93..9ba2e3a 100644
--- a/include/acpi/acpixf.h
+++ b/include/acpi/acpixf.h
@@ -74,6 +74,7 @@ extern u8 acpi_gbl_disable_auto_repair;
extern u32 acpi_current_gpe_count;
extern struct acpi_table_fadt acpi_gbl_FADT;
extern u8 acpi_gbl_system_awake_and_running;
+extern u8 acpi_gbl_reduced_hardware; /* ACPI 5.0 */
extern u32 acpi_rsdt_forced;
/*
--
1.7.9.rc1
--
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