From 82659cc91014df7dfcc55474c1657d1c9b6fe957 Mon Sep 17 00:00:00 2001
From: Simon Glass <sjg@chromium.org>
Date: Tue, 7 Jul 2020 21:32:10 -0600
Subject: [PATCH] acpi: Support generation of a scope

Add a function to write a scope to the generated ACPI code.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Wolfgang Wallner <wolfgang.wallner@br-automation.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
[bmeng: Fix build failures on Sandbox]
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
---
 include/acpi/acpigen.h |  9 +++++++++
 lib/acpi/acpigen.c     |  7 +++++++
 test/dm/acpi.c         |  3 +--
 test/dm/acpi.h         |  3 +++
 test/dm/acpigen.c      | 31 +++++++++++++++++++++++++++++++
 5 files changed, 51 insertions(+), 2 deletions(-)

diff --git a/include/acpi/acpigen.h b/include/acpi/acpigen.h
index c6644bc2b2..4a606125de 100644
--- a/include/acpi/acpigen.h
+++ b/include/acpi/acpigen.h
@@ -31,6 +31,7 @@ enum {
 	DWORD_PREFIX		= 0x0c,
 	STRING_PREFIX		= 0x0d,
 	QWORD_PREFIX		= 0x0e,
+	SCOPE_OP		= 0x10,
 	BUFFER_OP		= 0x11,
 	PACKAGE_OP		= 0x12,
 	METHOD_OP		= 0x14,
@@ -261,6 +262,14 @@ void acpigen_emit_namestring(struct acpi_ctx *ctx, const char *namepath);
  */
 void acpigen_write_name(struct acpi_ctx *ctx, const char *namepath);
 
+/**
+ * acpigen_write_scope() - Write a scope
+ *
+ * @ctx: ACPI context pointer
+ * @scope: Scope to write (e.g. "\\_SB.ABCD")
+ */
+void acpigen_write_scope(struct acpi_ctx *ctx, const char *scope);
+
 /**
  * acpigen_write_uuid() - Write a UUID
  *
diff --git a/lib/acpi/acpigen.c b/lib/acpi/acpigen.c
index 45216c1f9d..1e0a489d7b 100644
--- a/lib/acpi/acpigen.c
+++ b/lib/acpi/acpigen.c
@@ -258,6 +258,13 @@ void acpigen_write_name(struct acpi_ctx *ctx, const char *namepath)
 	acpigen_emit_namestring(ctx, namepath);
 }
 
+void acpigen_write_scope(struct acpi_ctx *ctx, const char *scope)
+{
+	acpigen_emit_byte(ctx, SCOPE_OP);
+	acpigen_write_len_f(ctx);
+	acpigen_emit_namestring(ctx, scope);
+}
+
 static void acpigen_write_method_internal(struct acpi_ctx *ctx,
 					  const char *name, uint flags)
 {
diff --git a/test/dm/acpi.c b/test/dm/acpi.c
index 7768f9514c..b94c4ba4d1 100644
--- a/test/dm/acpi.c
+++ b/test/dm/acpi.c
@@ -20,9 +20,8 @@
 #include <dm/acpi.h>
 #include <dm/test.h>
 #include <test/ut.h>
+#include "acpi.h"
 
-#define ACPI_TEST_DEV_NAME	"ABCD"
-#define ACPI_TEST_CHILD_NAME	"EFGH"
 #define BUF_SIZE		4096
 
 /**
diff --git a/test/dm/acpi.h b/test/dm/acpi.h
index 885dff85d3..535db56b51 100644
--- a/test/dm/acpi.h
+++ b/test/dm/acpi.h
@@ -9,6 +9,9 @@
 #ifndef __TEST_DM_ACPI_H
 #define __TEST_DM_ACPI_H
 
+#define ACPI_TEST_DEV_NAME	"ABCD"
+#define ACPI_TEST_CHILD_NAME	"EFGH"
+
 /**
  * acpi_test_alloc_context_size() - Allocate an ACPI context of a given size
  *
diff --git a/test/dm/acpigen.c b/test/dm/acpigen.c
index f25be938a4..46792d8e89 100644
--- a/test/dm/acpigen.c
+++ b/test/dm/acpigen.c
@@ -916,3 +916,34 @@ static int dm_test_acpi_write_values(struct unit_test_state *uts)
 	return 0;
 }
 DM_TEST(dm_test_acpi_write_values, 0);
+
+/* Test writing a scope */
+static int dm_test_acpi_scope(struct unit_test_state *uts)
+{
+	char buf[ACPI_PATH_MAX];
+	struct acpi_ctx *ctx;
+	struct udevice *dev;
+	u8 *ptr;
+
+	ut_assertok(alloc_context(&ctx));
+	ptr = acpigen_get_current(ctx);
+
+	ut_assertok(uclass_first_device_err(UCLASS_TEST_ACPI, &dev));
+	ut_assertok(acpi_device_path(dev, buf, sizeof(buf)));
+	acpigen_write_scope(ctx, buf);
+	acpigen_pop_len(ctx);
+
+	ut_asserteq(SCOPE_OP, *ptr++);
+	ut_asserteq(13, acpi_test_get_length(ptr));
+	ptr += 3;
+	ut_asserteq(ROOT_PREFIX, *ptr++);
+	ut_asserteq(DUAL_NAME_PREFIX, *ptr++);
+	ut_asserteq_strn("_SB_" ACPI_TEST_DEV_NAME, (char *)ptr);
+	ptr += 8;
+	ut_asserteq_ptr(ptr, ctx->current);
+
+	free_context(&ctx);
+
+	return 0;
+}
+DM_TEST(dm_test_acpi_scope, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);
-- 
2.39.5