From c4c341b3f915d8402876fbe44c14677f43942cb2 Mon Sep 17 00:00:00 2001
From: Ondrej Mikle <ondrej.mikle@gmail.com>
Date: Thu, 14 May 2020 12:46:25 +0200
Subject: [PATCH] core: setup stack when running core on T1

---
 core/embed/firmware/startup.s | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/core/embed/firmware/startup.s b/core/embed/firmware/startup.s
index cbcfb67bd6..03081990a8 100644
--- a/core/embed/firmware/startup.s
+++ b/core/embed/firmware/startup.s
@@ -5,6 +5,14 @@
   .global reset_handler
   .type reset_handler, STT_FUNC
 reset_handler:
+
+#if TREZOR_MODEL == 1
+  ldr r0, =_estack - 8  // r0 = stack pointer, T1 bootloader had 8 bytes reserved at end
+  msr msp, r0           // set stack pointer
+  dsb
+  isb
+#endif
+
   // setup environment for subsequent stage of code
   ldr r0, =ccmram_start // r0 - point to beginning of CCMRAM
   ldr r1, =ccmram_end   // r1 - point to byte after the end of CCMRAM