acpi: Support generation of ACPI code

Add a new file to handle generating ACPI code programatically. This is
used when information must be dynamically added to the tables, e.g. the
SSDT.

Initial support is just for writing simple values. Also add a 'base' value
so that the table can be freed. This likely doesn't happen in normal code,
but is nice to do in tests.

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>

2 files changed, 73 insertions, 0 deletions

diff --git a/test/dm/Makefile b/test/dm/Makefile
index 0d1c66fa1e..5641070ea1 100644
--- a/test/dm/Makefile
+++ b/test/dm/Makefile
@@ -14,6 +14,7 @@ obj-$(CONFIG_UT_DM) += test-uclass.o
 obj-$(CONFIG_UT_DM) += core.o
 ifneq ($(CONFIG_SANDBOX),)
 obj-$(CONFIG_ACPIGEN) += acpi.o
+obj-$(CONFIG_ACPIGEN) += acpigen.o
 obj-$(CONFIG_SOUND) += audio.o
 obj-$(CONFIG_BLK) += blk.o
 obj-$(CONFIG_BOARD) += board.o
diff --git a/test/dm/acpigen.c b/test/dm/acpigen.c
new file mode 100644
index 0000000000..9ff9b68532
--- /dev/null
+++ b/test/dm/acpigen.c
@@ -0,0 +1,72 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Tests for ACPI code generation
+ *
+ * Copyright 2019 Google LLC
+ * Written by Simon Glass <sjg@chromium.org>
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <malloc.h>
+#include <acpi/acpigen.h>
+#include <asm/unaligned.h>
+#include <dm/acpi.h>
+#include <dm/test.h>
+#include <test/ut.h>
+
+/* Maximum size of the ACPI context needed for most tests */
+#define ACPI_CONTEXT_SIZE	150
+
+static int alloc_context(struct acpi_ctx **ctxp)
+{
+	struct acpi_ctx *ctx;
+
+	*ctxp = NULL;
+	ctx = malloc(sizeof(*ctx));
+	if (!ctx)
+		return -ENOMEM;
+	ctx->base = malloc(ACPI_CONTEXT_SIZE);
+	if (!ctx->base) {
+		free(ctx);
+		return -ENOMEM;
+	}
+	ctx->current = ctx->base;
+	*ctxp = ctx;
+
+	return 0;
+}
+
+static void free_context(struct acpi_ctx **ctxp)
+{
+	free((*ctxp)->base);
+	free(*ctxp);
+	*ctxp = NULL;
+}
+
+/* Test emitting simple types and acpigen_get_current() */
+static int dm_test_acpi_emit_simple(struct unit_test_state *uts)
+{
+	struct acpi_ctx *ctx;
+	u8 *ptr;
+
+	ut_assertok(alloc_context(&ctx));
+
+	ptr = acpigen_get_current(ctx);
+	acpigen_emit_byte(ctx, 0x23);
+	ut_asserteq(1, acpigen_get_current(ctx) - ptr);
+	ut_asserteq(0x23, *(u8 *)ptr);
+
+	acpigen_emit_word(ctx, 0x1234);
+	ut_asserteq(3, acpigen_get_current(ctx) - ptr);
+	ut_asserteq(0x1234, get_unaligned((u16 *)(ptr + 1)));
+
+	acpigen_emit_dword(ctx, 0x87654321);
+	ut_asserteq(7, acpigen_get_current(ctx) - ptr);
+	ut_asserteq(0x87654321, get_unaligned((u32 *)(ptr + 3)));
+
+	free_context(&ctx);
+
+	return 0;
+}
+DM_TEST(dm_test_acpi_emit_simple, 0);