acpi: enable writing ACPI tables on QEMU

Invoke write_acpi_tables() via EVT_LAST_STAGE_INIT on QEMU except on X86.
X86 calls write_acpi_tables() in write_tables().

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/misc/qfw_acpi.c b/drivers/misc/qfw_acpi.c
index 6e14b2a..7ffed1e 100644
--- a/drivers/misc/qfw_acpi.c
+++ b/drivers/misc/qfw_acpi.c
@@ -9,9 +9,11 @@
 #include <acpi/acpi_table.h>
 #include <errno.h>
 #include <malloc.h>
+#include <mapmem.h>
 #include <qfw.h>
 #include <tables_csum.h>
 #include <stdio.h>
+#include <linux/sizes.h>
 #include <asm/byteorder.h>
 #include <asm/global_data.h>
 
@@ -254,3 +256,26 @@
 	file = qfw_find_file(dev, "etc/acpi/rsdp");
 	return file->addr;
 }
+
+#ifndef CONFIG_X86
+static int evt_write_acpi_tables(void)
+{
+	ulong addr, end;
+	void *ptr;
+
+	/* Reserve 64K for ACPI tables, aligned to a 4K boundary */
+	ptr = memalign(SZ_4K, SZ_64K);
+	if (!ptr)
+		return -ENOMEM;
+	addr = map_to_sysmem(ptr);
+
+	/* Generate ACPI tables */
+	end = write_acpi_tables(addr);
+	gd->arch.table_start = addr;
+	gd->arch.table_end = addr;
+
+	return 0;
+}
+
+EVENT_SPY_SIMPLE(EVT_LAST_STAGE_INIT, evt_write_acpi_tables);
+#endif