xen/arm64: head: Document enable_mmu()

Document the behavior and the main registers usage within enable_mmu().

Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>

diff --git a/xen/arch/arm/arm64/head.S b/xen/arch/arm/arm64/head.S
index eddf66302179c6032faf3586d96ebcfb02e37e28..63563ef5e34120b7e2d4fa6fa5cca94e29121f29 100644 (file)
--- a/xen/arch/arm/arm64/head.S
+++ b/xen/arch/arm/arm64/head.S
@@ -576,6 +576,13 @@ virtphys_clash:
         ret
 ENDPROC(create_page_tables)
 
+/*
+ * Turn on the Data Cache and the MMU. The function will return on the 1:1
+ * mapping. In other word, the caller is responsible to switch to the runtime
+ * mapping.
+ *
+ * Clobbers x0 - x3
+ */
 enable_mmu:
         PRINT("- Turning on paging -\r\n")