From 1be5140850575eb69a37ce5671744e4697da685d Mon Sep 17 00:00:00 2001
From: Michael Cardell Widerkrantz <mc@tillitis.se>
Date: Tue, 8 Apr 2025 13:30:05 +0200
Subject: [PATCH] tkey-libs: Optimize for size

Optimize tkey-libs for size to fit firmware in ROM
---
 README.md                              | 12 +++++++++++-
 hw/application_fpga/tkey-libs/Makefile |  2 +-
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/README.md b/README.md
index 1d182e7..9cd4878 100644
--- a/README.md
+++ b/README.md
@@ -122,7 +122,17 @@ official version tag.
 
 Easiest is probably to just remove the tkey-libs directory and then
 git clone the desired tag. Use the entire repo, but remove the .-files
-like `.git`, `.github`, et cetera.
+like `.git`, `.github`, et cetera. Something like:
+
+```
+$ rm -rf tkey-libs
+$ git clone git@github.com:tillitis/tkey-libs.git
+$ cd tkey-libs
+$ git checkout fw-3
+```
+
+Note that you need to change the optimization flag in the tkey-libs'
+Makefile to `-Os`.
 
 ## Measured boot
 
diff --git a/hw/application_fpga/tkey-libs/Makefile b/hw/application_fpga/tkey-libs/Makefile
index 3c1cdf5..9dea0d9 100644
--- a/hw/application_fpga/tkey-libs/Makefile
+++ b/hw/application_fpga/tkey-libs/Makefile
@@ -17,7 +17,7 @@ INCLUDE=include
 # either of them. You don't need to recompile tkey-libs.
 
 CFLAGS = -target riscv32-unknown-none-elf -march=rv32iczmmul -mabi=ilp32 \
-	-mcmodel=medany -static -std=gnu99 -O2 -ffast-math -fno-common \
+	-mcmodel=medany -static -std=gnu99 -Os -ffast-math -fno-common \
 	-fno-builtin-printf -fno-builtin-putchar -nostdlib -mno-relax -flto \
 	-Wall -Werror=implicit-function-declaration \
 	-I $(INCLUDE) -I .