1 files changed, 91 insertions, 0 deletions
diff --git a/lib/acpi/acpi_writer.c b/lib/acpi/acpi_writer.c
new file mode 100644
index 00000000000..5ddffc87343
--- /dev/null
+++ b/lib/acpi/acpi_writer.c
@@ -0,0 +1,91 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Handles writing the declared ACPI tables
+ *
+ * Copyright 2021 Google LLC
+ */
+
+#define LOG_CATEGORY LOGC_ACPI
+
+#include <common.h>
+#include <log.h>
+#include <malloc.h>
+#include <mapmem.h>
+#include <acpi/acpi_table.h>
+#include <asm/global_data.h>
+#include <dm/acpi.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+int acpi_write_one(struct acpi_ctx *ctx, const struct acpi_writer *entry)
+{
+	int ret;
+
+	log_debug("%s: writing table '%s'\n", entry->name,
+		  entry->table);
+	ctx->tab_start = ctx->current;
+	ret = entry->h_write(ctx, entry);
+	if (ret == -ENOENT) {
+		log_debug("%s: Omitted due to being empty\n",
+			  entry->name);
+		ret = 0;
+		ctx->current = ctx->tab_start;	/* drop the table */
+		return ret;
+	}
+	if (ret)
+		return log_msg_ret("write", ret);
+
+	acpi_align(ctx);
+
+	return 0;
+}
+
+static int acpi_write_all(struct acpi_ctx *ctx)
+{
+	const struct acpi_writer *writer =
+		 ll_entry_start(struct acpi_writer, acpi_writer);
+	const int n_ents = ll_entry_count(struct acpi_writer, acpi_writer);
+	const struct acpi_writer *entry;
+	int ret;
+
+	for (entry = writer; entry != writer + n_ents; entry++) {
+		ret = acpi_write_one(ctx, entry);
+		if (ret && ret != -ENOENT)
+			return log_msg_ret("one", ret);
+	}
+
+	return 0;
+}
+
+/*
+ * QEMU's version of write_acpi_tables is defined in drivers/misc/qfw.c
+ */
+ulong write_acpi_tables(ulong start_addr)
+{
+	struct acpi_ctx *ctx;
+	ulong addr;
+	void *start;
+	int ret;
+
+	ctx = calloc(1, sizeof(*ctx));
+	if (!ctx)
+		return log_msg_ret("mem", -ENOMEM);
+	gd->acpi_ctx = ctx;
+
+	start = map_sysmem(start_addr, 0);
+
+	log_debug("ACPI: Writing ACPI tables at %lx\n", start_addr);
+
+	acpi_reset_items();
+
+	ret = acpi_write_all(ctx);
+	if (ret) {
+		log_err("Failed to write ACPI tables (err=%d)\n", ret);
+		return log_msg_ret("write", -ENOMEM);
+	}
+
+	addr = map_to_sysmem(ctx->current);
+	log_debug("ACPI current = %lx\n", addr);
+
+	return addr;
+}