From e87d3fa804f5816021d7925bfd2755a1bcbb0833 Mon Sep 17 00:00:00 2001
From: Steam Deck User <motolegacy.git@gmail.com>
Date: Fri, 14 Apr 2023 10:55:00 -0400
Subject: [PATCH] build.mak: Improve and streamline .SFO creation

The current state of building .SFO binaries is rather primitive --
as it stood, build.mak forced its own flags to be used, always.
If you were building without PSP_LARGE_MEMORY, build.mak would use
a deprecated tool for generation as well, one that cobbles together
undocumented flags in an array of bytes and shoves it into a file.

The first change this commit makes is by enabling use of the "new"
mkfsoex, which creates a smaller but still bootable SFO without
any arguments given. Developers are now able to provide custom
SFO flags now using this, added via `SFOFLAGS` in their Makefile.

This means that developers can now (at their own discretion) provide
custom region information, parental control level, minimum firmware
boot level, etc. with:

```make
SFOFLAGS = -d REGION=16394 -d PARENTAL_LEVEL=4 -s PSP_SYSTEM_VER=4.01
```

As a side-effect, this also makes the SDK more adapted to new
custom firmware releases that may add new SFO flags.

The second change made is turning `PSP_LARGE_MEMORY` into an opt-out
/enabled by default flag if developers are targeting a firmware
version newer than 3.90. Custom firmware versions starting from
4.01 M33 guard against expanding the user memory partition to 52mB
if the unit detected is PSP-1000. Therefore having this check in
place becomes redundant, potentially complicating Makefiles. A
warning is printed out allowing developers to be aware of this fact
and removing the flag from their Makefile.
---
 src/base/build.mak | 26 ++++++++++++++++++++------
 1 file changed, 20 insertions(+), 6 deletions(-)

diff --git a/src/base/build.mak b/src/base/build.mak
index 9081a75f..befd59b7 100644
--- a/src/base/build.mak
+++ b/src/base/build.mak
@@ -21,7 +21,7 @@ LD       = psp-gcc
 AR       = psp-gcc-ar
 RANLIB   = psp-gcc-ranlib
 STRIP    = psp-strip
-MKSFO    = mksfo
+MKSFO    = mksfoex
 PACK_PBP = pack-pbp
 FIXUP    = psp-fixup-imports
 ENC		 = PrxEncrypter
@@ -34,14 +34,28 @@ CFLAGS   := $(addprefix -I,$(INCDIR)) -G0 $(CFLAGS)
 CXXFLAGS := $(CFLAGS) $(CXXFLAGS)
 ASFLAGS  := $(CFLAGS) $(ASFLAGS)
 
-ifeq ($(PSP_LARGE_MEMORY),1)
-MKSFO = mksfoex -d MEMSIZE=1
-endif
-
 ifeq ($(PSP_FW_VERSION),)
 PSP_FW_VERSION=150
 endif
 
+# CFW versions after M33 3.90 guard against expanding the
+# user memory partition on PSP-1000, making MEMSIZE obsolete.
+# It is now an opt-out policy with PSP_LARGE_MEMORY=0
+ifeq ($(shell test $(PSP_FW_VERSION) -gt 390; echo $$?),0)
+ifeq ($(PSP_LARGE_MEMORY),1)
+$(warning "PSP_LARGE_MEMORY" flag is not necessary targeting firmware versions above 3.90)
+else ifeq ($(PSP_LARGE_MEMORY),0)
+SFOFLAGS := -d MEMSIZE=0 $(SFOFLAGS)
+else
+SFOFLAGS := -d MEMSIZE=1 $(SFOFLAGS)
+endif
+else
+ifeq ($(PSP_LARGE_MEMORY),1)
+SFOFLAGS := -d MEMSIZE=1 $(SFOFLAGS)
+endif
+endif
+
+
 CFLAGS += -D_PSP_FW_VERSION=$(PSP_FW_VERSION)
 CXXFLAGS += -D_PSP_FW_VERSION=$(PSP_FW_VERSION)
 
@@ -152,7 +166,7 @@ $(TARGET_LIB): $(OBJS)
 	$(RANLIB) $@
 
 $(PSP_EBOOT_SFO): 
-	$(MKSFO) '$(PSP_EBOOT_TITLE)' $@
+	$(MKSFO) $(SFOFLAGS) '$(PSP_EBOOT_TITLE)' $@
 
 ifeq ($(BUILD_PRX),1)
 $(PSP_EBOOT): $(TARGET).prx $(PSP_EBOOT_SFO)