[U-Boot] [RFC] efi_loader: support for CONFIG_ARMV7_NONSEC

[Heinrich Schuchardt <xypron.glpk@gmx.de>]

Booting with SMP fails on the Allwinner A20 CPU.
https://gist.github.com/xypron/2524ba898d6905d959c744c2b05da196

When executing bootefi we need to
* copy the Power State Coordination Interface (PSCI) code to its
  destination address
* switch between our hypervisor mode (HYP) and the supervisor mode (SVC)
  of the payload (http://linux-sunxi.org/PSCI)

This patch is incomplete. It is just meant to indicate where we could
change the entry point.

With the patch iPXE cannot get a network address.

Possibly a better moment for switching to SVC is ExitBootServices.

We also have to consider switching modes at EFI_ENTRY and EFI_EXIT.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
---
 cmd/bootefi.c | 18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/cmd/bootefi.c b/cmd/bootefi.c
index 85f7b42e76..af5adf8b29 100644
--- a/cmd/bootefi.c
+++ b/cmd/bootefi.c
@@ -17,8 +17,10 @@
 #include <linux/libfdt_env.h>
 #include <memalign.h>
 #include <asm/global_data.h>
+#include <asm/armv7.h>
 #include <asm-generic/sections.h>
 #include <asm-generic/unaligned.h>
+#include <asm/secure.h>
 #include <linux/linkage.h>
 
 DECLARE_GLOBAL_DATA_PTR;
@@ -176,8 +178,19 @@ static efi_status_t efi_do_enter(
 {
 	efi_status_t ret = EFI_LOAD_ERROR;
 
-	if (entry)
-		ret = entry(image_handle, st);
+	if (entry) {
+#ifdef CONFIG_ARMV7_NONSEC
+		if (armv7_boot_nonsec()) {
+			armv7_init_nonsec();
+			secure_ram_addr(_do_nonsec_entry)(entry,
+					(uintptr_t)image_handle,
+					(uintptr_t)st, 0);
+		} else
+#endif
+		{
+			ret = entry(image_handle, st);
+		}
+	}
 	st->boottime->exit(image_handle, ret, 0, NULL);
 	return ret;
 }
-- 
2.14.2