Hi Alex
-----Original Message----- From: Alexander Graf [mailto:agraf@suse.de] Sent: Tuesday, June 21, 2016 4:37 AM To: u-boot@lists.denx.de Cc: york sun york.sun@nxp.com; Prabhakar Kushwaha prabhakar.kushwaha@nxp.com Subject: [PATCH v4 2/9] efi_loader: AArch64: Run EFI payloads in EL2 if U- Boot runs in EL3
Some boards decided not to run ATF or other secure firmware in EL3, so they instead run U-Boot there. The uEFI spec doesn't know what EL3 is though - it only knows about EL2 and EL1. So if we see that we're running in EL3, let's get into EL2 to make payloads happy.
Signed-off-by: Alexander Graf agraf@suse.de
<snip>
asm volatile("isb"); diff --git a/cmd/bootefi.c b/cmd/bootefi.c index 2169065..edd0980 100644 --- a/cmd/bootefi.c +++ b/cmd/bootefi.c @@ -205,6 +205,17 @@ static unsigned long do_bootefi_exec(void *efi, void *fdt) loaded_image_info.device_handle = nethandle; #endif
+#ifdef CONFIG_ARM64
- /* On AArch64 we need to make sure we call our payload in < EL3 */
- if (current_el() == 3) {
smp_kick_all_cpus();dcache_disable(); /* flush cache before switch to EL2 */armv8_switch_to_el2();/* Enable caches again */set_sctlr(get_sctlr() | (CR_C|CR_M));- }
As exception level switch to EL2. Who is creating MMU table for EL2.
--prabhakar