From f7f758d4d1c7cd7e0c1cf1d9f4e0d98ed48a29f8 Mon Sep 17 00:00:00 2001
From: Christian Herber <christian.herber@oss.nxp.com>
Date: Mon, 22 Sep 2025 14:00:52 +0200
Subject: [PATCH 1/3] Smtp: Making stack layout normative

---
 src/aclic.adoc | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/src/aclic.adoc b/src/aclic.adoc
index 8cd8b51..3c1c8e1 100644
--- a/src/aclic.adoc
+++ b/src/aclic.adoc
@@ -1044,9 +1044,9 @@ Once the instruction retires, or the interrupts are disabled, no late preemption
 
 === Stack layout
 
-To ease debugging, a stack layout is recommended for the saved context.
-
-NOTE: This stack layout is not mandated to allow e.g. shadow register sets
+Trap handlers may need to access stacked context.
+E.g. an ECALL handler needs to increment the epc value by 4 to avoid re-executing the ECALL instruction.
+To simplify access to the stacked context, the stack layout is defined as follows.
 
 [source]
 ----
@@ -1060,8 +1060,8 @@ stack pointer adjustment: 32
 20: x14
 16: x13
 12: x12
-8: x11
-4: x10
+ 8: x11
+ 4: x10
 
 ** XLEN = 64:
 
@@ -1072,7 +1072,7 @@ stack pointer adjustment: 48
 32: x13
 24: x12
 16: x11
-8: x10
+ 8: x10
 
 * Smnip/Ssnip present:
 

From dca3ed4d72869988e6d81d0e3c5e4043641e04b5 Mon Sep 17 00:00:00 2001
From: Christian Herber <christian.herber@oss.nxp.com>
Date: Mon, 22 Sep 2025 14:02:54 +0200
Subject: [PATCH 2/3] Smtp: Fixing typo in stack definition

Closes #607
---
 src/aclic.adoc | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/aclic.adoc b/src/aclic.adoc
index 3c1c8e1..891e47d 100644
--- a/src/aclic.adoc
+++ b/src/aclic.adoc
@@ -1085,11 +1085,11 @@ stack pointer adjustment: 32
 32: xpistatus (XLEN)
 28: xpepc (XLEN)
 
-** XLEN = 32
+** XLEN = 64
 
 stack pointer adjustment: 64
 
-60: xpistatus (XLEN)
+64: xpistatus (XLEN)
 56: xpepc (XLEN)
 ----
 

From d65e7ba8f650befed40cfbd1b6f714ba7bf7ff5b Mon Sep 17 00:00:00 2001
From: Christian Herber <christian.herber@oss.nxp.com>
Date: Fri, 26 Sep 2025 12:43:41 +0200
Subject: [PATCH 3/3] Smtp: changing stack offsets to negative ones

---
 src/aclic.adoc | 32 ++++++++++++++++----------------
 1 file changed, 16 insertions(+), 16 deletions(-)

diff --git a/src/aclic.adoc b/src/aclic.adoc
index 891e47d..7e1bda0 100644
--- a/src/aclic.adoc
+++ b/src/aclic.adoc
@@ -1056,23 +1056,23 @@ To simplify access to the stacked context, the stack layout is defined as follow
 
 stack pointer adjustment: 32
 
-24: x15
-20: x14
-16: x13
-12: x12
- 8: x11
- 4: x10
+-24: x15
+-20: x14
+-16: x13
+-12: x12
+ -8: x11
+ -4: x10
 
 ** XLEN = 64:
 
 stack pointer adjustment: 48
 
-48: x15
-40: x14
-32: x13
-24: x12
-16: x11
- 8: x10
+-48: x15
+-40: x14
+-32: x13
+-24: x12
+-16: x11
+ -8: x10
 
 * Smnip/Ssnip present:
 
@@ -1082,15 +1082,15 @@ start of stackframe remains same. In addition:
 
 stack pointer adjustment: 32
 
-32: xpistatus (XLEN)
-28: xpepc (XLEN)
+-32: xpistatus (XLEN)
+-28: xpepc (XLEN)
 
 ** XLEN = 64
 
 stack pointer adjustment: 64
 
-64: xpistatus (XLEN)
-56: xpepc (XLEN)
+-64: xpistatus (XLEN)
+-56: xpepc (XLEN)
 ----
 
 === Fault handling