Tegra: relocate code to BL31_BASE during cold boot
This patch adds support to relocate BL3-1 code to BL31_BASE in case
we cold boot to a different address. This is particularly useful to
maintain compatibility with legacy BL2 code.
This patch also checks to see if the image base address matches either
the TZDRAM or TZSRAM base.
Change-Id: I72c96d7f89076701a6ac2537d4c06565c54dab9c
Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>
diff --git a/plat/nvidia/tegra/common/aarch64/tegra_helpers.S b/plat/nvidia/tegra/common/aarch64/tegra_helpers.S
index 6851b15..8ca10e2 100644
--- a/plat/nvidia/tegra/common/aarch64/tegra_helpers.S
+++ b/plat/nvidia/tegra/common/aarch64/tegra_helpers.S
@@ -254,6 +254,47 @@
*/
func plat_reset_handler
+ /* ----------------------------------------------------
+ * Verify if we are running from BL31_BASE address
+ * ----------------------------------------------------
+ */
+ adr x18, bl31_entrypoint
+ mov x17, #BL31_BASE
+ cmp x18, x17
+ b.eq 1f
+
+ /* ----------------------------------------------------
+ * Copy the entire BL31 code to BL31_BASE if we are not
+ * running from it already
+ * ----------------------------------------------------
+ */
+ mov x0, x17
+ mov x1, x18
+ mov x2, #BL31_SIZE
+_loop16:
+ cmp x2, #16
+ b.lt _loop1
+ ldp x3, x4, [x1], #16
+ stp x3, x4, [x0], #16
+ sub x2, x2, #16
+ b _loop16
+ /* copy byte per byte */
+_loop1:
+ cbz x2, _end
+ ldrb w3, [x1], #1
+ strb w3, [x0], #1
+ subs x2, x2, #1
+ b.ne _loop1
+
+ /* ----------------------------------------------------
+ * Jump to BL31_BASE and start execution again
+ * ----------------------------------------------------
+ */
+_end: mov x0, x20
+ mov x1, x21
+ br x17
+1:
+
/* -----------------------------------
* derive and save the phys_base addr
* -----------------------------------