From 663c446439d110453b2d22275d7fddf6410dcc99 Mon Sep 17 00:00:00 2001
From: TuxSH <tuxsh@sfr.fr>
Date: Wed, 21 Feb 2018 00:53:23 +0100
Subject: [PATCH] Mention that Nintendo copy-pasted some startup code from
 arm-trusted-firmware

---
 exosphere/smc_user.c   |  4 ++--
 exosphere/start.cold.s | 21 +++++++++++++++++++--
 exosphere/start.warm.s | 21 +++++++++++++++++++--
 3 files changed, 40 insertions(+), 6 deletions(-)

diff --git a/exosphere/smc_user.c b/exosphere/smc_user.c
index d05a7997a..b79fe0927 100644
--- a/exosphere/smc_user.c
+++ b/exosphere/smc_user.c
@@ -417,7 +417,7 @@ uint32_t user_decrypt_rsa_private_key(smc_args_t *args) {
     }
     is_personalized = (int)args->X[3];
     user_address = (void *)args->X[4];
-    size = = (size_t)args->X[5];
+    size = (size_t)args->X[5];
     wrapped_key[0] = args->X[6];
     wrapped_key[1] = args->X[7];
     
@@ -609,4 +609,4 @@ uint32_t user_unwrap_aes_wrapped_titlekey(smc_args_t *args) {
     
     args->X[1] = sealed_titlekey[0];
     args->X[2] = sealed_titlekey[1];
-}
\ No newline at end of file
+}
diff --git a/exosphere/start.cold.s b/exosphere/start.cold.s
index be0bdf862..f959358bc 100644
--- a/exosphere/start.cold.s
+++ b/exosphere/start.cold.s
@@ -1,7 +1,14 @@
-.align      4
+.align      6
 .section    .text.cold.start, "ax", %progbits
 .global     __start_cold
 __start_cold:
+    /* Nintendo copy-pasted https://github.com/ARM-software/arm-trusted-firmware/blob/master/plat/nvidia/tegra/common/aarch64/tegra_helpers.S#L312 */
+        /*
+        * Copyright (c) 2015-2017, ARM Limited and Contributors. All rights reserved.
+        *
+        * SPDX-License-Identifier: BSD-3-Clause
+        */
+    /* The following comments are mine. */
     /* mask all interrupts */
     msr daifset, daif
 
@@ -25,6 +32,10 @@ __start_cold:
     bic  x0, x0, #1
     msr  cpuactlr_el1, x0
 
+.rept 7
+    nop                     /* wait long enough for the write to cpuactlr_el1 to have completed */
+.endr
+
     /* if the OS lock is set, disable it and request a warm reset */
     mrs  x0, oslsr_el1
     ands x0, x0, #2
@@ -39,7 +50,13 @@ __start_cold:
     msr  rmr_el3, x0
     isb
     dsb
-    wfi
+    /* Nintendo forgot to copy-paste the branch instruction below. */
+    _reset_wfi:
+        wfi
+        b _reset_wfi
+.rept 65
+    nop                     /* guard against speculative excecution */
+.endr
 
     _set_lock_and_sp:
     /* set the OS lock */
diff --git a/exosphere/start.warm.s b/exosphere/start.warm.s
index b39b3b337..a27fbf528 100644
--- a/exosphere/start.warm.s
+++ b/exosphere/start.warm.s
@@ -1,7 +1,14 @@
-.align      4
+.align      6
 .section    .text.warm.start, "ax", %progbits
 .global     __start_warm
 __start_warm:
+        /* Nintendo copy-pasted https://github.com/ARM-software/arm-trusted-firmware/blob/master/plat/nvidia/tegra/common/aarch64/tegra_helpers.S#L312 */
+        /*
+        * Copyright (c) 2015-2017, ARM Limited and Contributors. All rights reserved.
+        *
+        * SPDX-License-Identifier: BSD-3-Clause
+        */
+    /* The following comments are mine. */
     /* mask all interrupts */
     msr daifset, daif
 
@@ -25,6 +32,10 @@ __start_warm:
     bic  x0, x0, #1
     msr  cpuactlr_el1, x0
 
+.rept 7
+    nop                     /* wait long enough for the write to cpuactlr_el1 to have completed */
+.endr
+
     /* if the OS lock is set, disable it and request a warm reset */
     mrs  x0, oslsr_el1
     ands x0, x0, #2
@@ -39,7 +50,13 @@ __start_warm:
     msr  rmr_el3, x0
     isb
     dsb
-    wfi
+    /* Nintendo forgot to copy-paste the branch instruction below. */
+    _reset_wfi:
+        wfi
+        b _reset_wfi
+.rept 65
+    nop                     /* guard against speculative excecution */
+.endr
 
     _set_lock_and_sp:
     /* set the OS lock */