From 474a62bc74fe923cd6f43e13ca82b1ce2f40e76f Mon Sep 17 00:00:00 2001
From: Bin Meng <bmeng.cn@gmail.com>
Date: Wed, 18 Jul 2018 21:42:16 -0700
Subject: [PATCH] x86: acpi: Don't touch ACPI hardware in write_acpi_tables()

write_acpi_tables() currently touches ACPI hardware to switch to
ACPI mode at the end. Move such operation out of this function,
so that it only does what the function name tells us.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 arch/x86/cpu/cpu.c        | 21 ++++++++++++++++++---
 arch/x86/lib/acpi_table.c | 11 -----------
 2 files changed, 18 insertions(+), 14 deletions(-)

diff --git a/arch/x86/cpu/cpu.c b/arch/x86/cpu/cpu.c
index d08b7d9b1e..290ee084e5 100644
--- a/arch/x86/cpu/cpu.c
+++ b/arch/x86/cpu/cpu.c
@@ -179,17 +179,32 @@ __weak void board_final_cleanup(void)
 
 int last_stage_init(void)
 {
+	struct acpi_fadt __maybe_unused *fadt;
+
 	board_final_cleanup();
 
-#if CONFIG_HAVE_ACPI_RESUME
-	struct acpi_fadt *fadt = acpi_find_fadt();
+#ifdef CONFIG_HAVE_ACPI_RESUME
+	fadt = acpi_find_fadt();
 
-	if (fadt != NULL && gd->arch.prev_sleep_state == ACPI_S3)
+	if (fadt && gd->arch.prev_sleep_state == ACPI_S3)
 		acpi_resume(fadt);
 #endif
 
 	write_tables();
 
+#ifdef CONFIG_GENERATE_ACPI_TABLE
+	fadt = acpi_find_fadt();
+
+	/* Don't touch ACPI hardware on HW reduced platforms */
+	if (fadt && !(fadt->flags & ACPI_FADT_HW_REDUCED_ACPI)) {
+		/*
+		 * Other than waiting for OSPM to request us to switch to ACPI
+		 * mode, do it by ourselves, since SMI will not be triggered.
+		 */
+		enter_acpi_mode(fadt->pm1a_cnt_blk);
+	}
+#endif
+
 	return 0;
 }
 #endif
diff --git a/arch/x86/lib/acpi_table.c b/arch/x86/lib/acpi_table.c
index e26c54d187..e48c9b9574 100644
--- a/arch/x86/lib/acpi_table.c
+++ b/arch/x86/lib/acpi_table.c
@@ -12,7 +12,6 @@
 #include <dm/uclass-internal.h>
 #include <version.h>
 #include <asm/acpi/global_nvs.h>
-#include <asm/acpi.h>
 #include <asm/acpi_table.h>
 #include <asm/ioapic.h>
 #include <asm/lapic.h>
@@ -444,16 +443,6 @@ ulong write_acpi_tables(ulong start)
 	acpi_rsdp_addr = (unsigned long)rsdp;
 	debug("ACPI: done\n");
 
-	/* Don't touch ACPI hardware on HW reduced platforms */
-	if (fadt->flags & ACPI_FADT_HW_REDUCED_ACPI)
-		return current;
-
-	/*
-	 * Other than waiting for OSPM to request us to switch to ACPI mode,
-	 * do it by ourselves, since SMI will not be triggered.
-	 */
-	enter_acpi_mode(fadt->pm1a_cnt_blk);
-
 	return current;
 }
 
-- 
2.25.1