From 733cc17ba79c8f4fa87878c28ac7788b72e2dc81 Mon Sep 17 00:00:00 2001
From: Polprzewodnikowy <sc@mateuszfaderewski.pl>
Date: Wed, 12 Jan 2022 16:14:08 +0100
Subject: [PATCH] more cleanup

---
 docker_build.sh            |  11 +--
 sw/n64/Makefile            |   3 +-
 sw/n64/src/boot.c          |   7 +-
 sw/n64/src/error.c         |   1 -
 sw/n64/src/exception.S     | 160 +++++++++++++++++++++----------------
 sw/n64/src/exception.c     |  11 ++-
 sw/n64/src/exception.h     |  13 ++-
 sw/n64/src/init.c          |  12 ++-
 sw/n64/src/init.h          |   9 +++
 sw/n64/src/interrupt.c     |   2 +-
 sw/n64/src/{sys.c => io.c} |   2 +-
 sw/n64/src/{sys.h => io.h} |  45 +----------
 sw/n64/src/ipl2.S          |  15 ++++
 sw/n64/src/main.c          |  10 +--
 sw/n64/src/regs.h          |  70 ++++++++++++++++
 sw/n64/src/sc64.h          |  12 +--
 sw/n64/src/startup.S       |  27 +------
 sw/pc/sc64.py              |  12 +--
 sw/riscv/src/cfg.c         |  11 +--
 19 files changed, 254 insertions(+), 179 deletions(-)
 create mode 100644 sw/n64/src/init.h
 rename sw/n64/src/{sys.c => io.c} (93%)
 rename sw/n64/src/{sys.h => io.h} (78%)
 create mode 100644 sw/n64/src/ipl2.S
 create mode 100644 sw/n64/src/regs.h

diff --git a/docker_build.sh b/docker_build.sh
index 169cea1..e44f8a2 100755
--- a/docker_build.sh
+++ b/docker_build.sh
@@ -1,14 +1,15 @@
 #!/bin/bash
 
-GIT_SHA=$(git rev-parse --short HEAD)
+GIT_BRANCH=$(git rev-parse --abbrev-ref HEAD)
+GIT_SHA=$(git rev-parse HEAD)
 GIT_TAG=$(git describe --tags --exact-match 2> /dev/null)
 
-if [ ! -z $GIT_TAG ]; then
-    __SC64_VERSION=$(printf "%.7q\ %.7q" $GIT_SHA $GIT_TAG)
-else
-    __SC64_VERSION=$(printf "%.7q\ develop" $GIT_SHA)
+if [ -z $GIT_TAG ]; then
+    GIT_TAG="develop"
 fi
 
+__SC64_VERSION=$(printf "[ %q | %q | %q ]" $GIT_BRANCH $GIT_TAG $GIT_SHA)
+
 docker run \
     --rm \
     --user $(id -u):$(id -g) \
diff --git a/sw/n64/Makefile b/sw/n64/Makefile
index 68bb773..61b1f9c 100644
--- a/sw/n64/Makefile
+++ b/sw/n64/Makefile
@@ -15,6 +15,7 @@ BUILD_DIR = build
 
 SRC_FILES = \
 	startup.S \
+	ipl2.S \
 	exception.S \
 	boot.c \
 	crc32.c \
@@ -23,10 +24,10 @@ SRC_FILES = \
 	font.c \
 	init.c \
 	interrupt.c \
+	io.c \
 	main.c \
 	sc64.c \
 	storage.c \
-	sys.c \
 	syscalls.c \
 	fatfs/diskio.c \
 	fatfs/ff.c \
diff --git a/sw/n64/src/boot.c b/sw/n64/src/boot.c
index 7cfbf20..b89c351 100644
--- a/sw/n64/src/boot.c
+++ b/sw/n64/src/boot.c
@@ -1,6 +1,7 @@
 #include "boot.h"
 #include "crc32.h"
-#include "sys.h"
+#include "init.h"
+#include "io.h"
 
 
 extern uint32_t ipl2 __attribute__((section(".data")));
@@ -131,6 +132,8 @@ void boot (boot_info_t *info) {
         io_write(&ipl3_dst[i], pi_io_read(&ipl3_src[i]));
     }
 
+    deinit();
+
     register void (*entry_point)(void) asm ("t3");
     register uint32_t boot_device asm ("s3");
     register uint32_t tv_type asm ("s4");
@@ -148,10 +151,8 @@ void boot (boot_info_t *info) {
     stack_pointer = (void *) UNCACHED(&SP_MEM->IMEM[1020]);
 
     asm volatile (
-        "mtc0 %[status], $12 \n"
         "move $sp, %[stack_pointer] \n"
         "jr %[entry_point] \n" ::
-        [status] "r" (C0_SR_CU1 | C0_SR_CU0 | C0_SR_FR),
         [entry_point] "r" (entry_point),
         [boot_device] "r" (boot_device),
         [tv_type] "r" (tv_type),
diff --git a/sw/n64/src/error.c b/sw/n64/src/error.c
index 4630e24..db7bb07 100644
--- a/sw/n64/src/error.c
+++ b/sw/n64/src/error.c
@@ -1,4 +1,3 @@
-#include "error.h"
 #include "exception.h"
 
 
diff --git a/sw/n64/src/exception.S b/sw/n64/src/exception.S
index 029039c..2af212b 100644
--- a/sw/n64/src/exception.S
+++ b/sw/n64/src/exception.S
@@ -1,62 +1,47 @@
-#define VECTOR_LOCATION         (0xA0000000UL)
-#define VECTOR_SIZE             (0x80)
-#define VECTOR_NUM              (4)
+#include "regs.h"
 
-#define HIT_INVALIDATE_I        ((4 << 2) | 0)
 
-#define TICKS_PER_SECOND        (93750000UL / 2)
-#define WATCHDOG_TIMEOUT        (10)
+#define WATCHDOG_TIMEOUT            (10 * (93750000UL / 2))
 
-#define C0_COUNT                $9
-#define C0_COMPARE              $11
-#define C0_STATUS               $12
-#define C0_CAUSE                $13
-#define C0_EPC                  $14
+#define VECTOR_LOCATION             (0xA0000000UL)
+#define VECTOR_SIZE                 (0x80)
+#define VECTOR_NUM                  (4)
 
-#define INTERRUPT_ENABLE        (1 << 0)
-#define INTERRUPT_MASK_TIMER    (1 << 15)
-
-#define EXCEPTION_CODE_MASK     (0x007C)
-#define EXCEPTION_CODE_BIT      (2)
-#define INTERRUPT_PENDING_MASK  (0xFF00)
-#define INTERRUPT_PENDING_BIT   (8)
-#define INTERRUPT_PENDING_TIMER (1 << 7)
-
-#define AT_OFFSET               (8)
-#define V0_OFFSET               (16)
-#define V1_OFFSET               (24)
-#define A0_OFFSET               (32)
-#define A1_OFFSET               (40)
-#define A2_OFFSET               (48)
-#define A3_OFFSET               (56)
-#define T0_OFFSET               (64)
-#define T1_OFFSET               (72)
-#define T2_OFFSET               (80)
-#define T3_OFFSET               (88)
-#define T4_OFFSET               (96)
-#define T5_OFFSET               (104)
-#define T6_OFFSET               (112)
-#define T7_OFFSET               (120)
-#define S0_OFFSET               (128)
-#define S1_OFFSET               (136)
-#define S2_OFFSET               (144)
-#define S3_OFFSET               (152)
-#define S4_OFFSET               (160)
-#define S5_OFFSET               (168)
-#define S6_OFFSET               (176)
-#define S7_OFFSET               (184)
-#define T8_OFFSET               (192)
-#define T9_OFFSET               (200)
-#define K0_OFFSET               (208)
-#define K1_OFFSET               (216)
-#define GP_OFFSET               (224)
-#define SP_OFFSET               (232)
-#define FP_OFFSET               (240)
-#define RA_OFFSET               (248)
-#define C0_STATUS_OFFSET        (256)
-#define C0_CAUSE_OFFSET         (260)
-#define C0_EPC_OFFSET           (264)
-#define SAVE_REGISTERS_SIZE     (272)
+#define AT_OFFSET                   (8)
+#define V0_OFFSET                   (16)
+#define V1_OFFSET                   (24)
+#define A0_OFFSET                   (32)
+#define A1_OFFSET                   (40)
+#define A2_OFFSET                   (48)
+#define A3_OFFSET                   (56)
+#define T0_OFFSET                   (64)
+#define T1_OFFSET                   (72)
+#define T2_OFFSET                   (80)
+#define T3_OFFSET                   (88)
+#define T4_OFFSET                   (96)
+#define T5_OFFSET                   (104)
+#define T6_OFFSET                   (112)
+#define T7_OFFSET                   (120)
+#define S0_OFFSET                   (128)
+#define S1_OFFSET                   (136)
+#define S2_OFFSET                   (144)
+#define S3_OFFSET                   (152)
+#define S4_OFFSET                   (160)
+#define S5_OFFSET                   (168)
+#define S6_OFFSET                   (176)
+#define S7_OFFSET                   (184)
+#define T8_OFFSET                   (192)
+#define T9_OFFSET                   (200)
+#define K0_OFFSET                   (208)
+#define K1_OFFSET                   (216)
+#define GP_OFFSET                   (224)
+#define SP_OFFSET                   (232)
+#define FP_OFFSET                   (240)
+#define RA_OFFSET                   (248)
+#define C0_STATUS_OFFSET            (256)
+#define C0_CAUSE_OFFSET             (260)
+#define C0_EPC_OFFSET               (264)
+#define SAVE_REGISTERS_SIZE         (272)
 
 
 .section .text.exception_handler
@@ -96,17 +81,17 @@ exception_handler:
 
     move $sp, $k0
 
-exception_is_fatal:
+exception_check_type:
     mfc0 $a0, C0_CAUSE
     sw $a0, C0_CAUSE_OFFSET($k0)
     move $a1, $a0
-    andi $a0, EXCEPTION_CODE_MASK
-    srl $a0, $a0, EXCEPTION_CODE_BIT
-    andi $a1, INTERRUPT_PENDING_MASK
-    srl $a1, $a1, INTERRUPT_PENDING_BIT
-    move $t0, $a1
-    andi $t0, INTERRUPT_PENDING_TIMER
-    bne $t0, $zero, exception_fatal
+    move $t0, $a0
+    andi $t0, C0_CR_IP7
+    andi $a0, C0_CR_EC_MASK
+    srl $a0, $a0, C0_CR_EC_BIT
+    andi $a1, C0_CR_IP_MASK
+    srl $a1, $a1, C0_CR_IP_BIT
+    # bne $t0, $zero, exception_fatal
     beq $a0, $zero, exception_interrupt
 
 exception_fatal:
@@ -194,10 +179,47 @@ exception_install:
     bne $t4, $t5, 2b
     addiu $t1, VECTOR_SIZE
     bne $t1, $t2, 1b
-    mtc0 $zero, C0_COUNT
-    li $t7, (WATCHDOG_TIMEOUT * TICKS_PER_SECOND)
-    mtc0 $t7, C0_COMPARE
-    mfc0 $t7, C0_STATUS
-    ori $t7, (INTERRUPT_MASK_TIMER | INTERRUPT_ENABLE)
-    mtc0 $t7, C0_STATUS
+    jr $ra
+
+
+.section .text.exception_disable_interrupts
+exception_disable_interrupts:
+    .global exception_disable_interrupts
+    mfc0 $t0, C0_STATUS
+    li $t1, ~(C0_SR_IE)
+    and $t0, $t0, $t1
+    mtc0 $t0, C0_STATUS
+    jr $ra
+
+
+.section .text.exception_enable_interrupts
+exception_enable_interrupts:
+    .global exception_enable_interrupts
+    mfc0 $t0, C0_STATUS
+    li $t1, C0_SR_IE
+    or $t0, $t0, $t1
+    mtc0 $t0, C0_STATUS
+    jr $ra
+
+
+.section .text.exception_enable_watchdog
+exception_enable_watchdog:
+    .global exception_enable_watchdog
+    mtc0 $zero, C0_COUNT
+    li $t1, WATCHDOG_TIMEOUT
+    mtc0 $t1, C0_COMPARE
+    mfc0 $t0, C0_STATUS
+    li $t1, C0_SR_IM7
+    or $t0, $t0, $t1
+    mtc0 $t0, C0_STATUS
+    jr $ra
+
+
+.section .text.exception_disable_watchdog
+exception_disable_watchdog:
+    .global exception_disable_watchdog
+    mfc0 $t0, C0_STATUS
+    li $t1, ~(C0_SR_IM7)
+    and $t0, $t0, $t1
+    mtc0 $t0, C0_STATUS
     jr $ra
diff --git a/sw/n64/src/exception.c b/sw/n64/src/exception.c
index d1951ba..663929f 100644
--- a/sw/n64/src/exception.c
+++ b/sw/n64/src/exception.c
@@ -2,7 +2,12 @@
 #include <stdio.h>
 #include "exception.h"
 #include "font.h"
-#include "sys.h"
+#include "io.h"
+#include "regs.h"
+
+
+#define STR(x)      #x
+#define XSTR(s)     STR(s)
 
 
 typedef union {
@@ -217,8 +222,8 @@ void exception_fatal_handler (uint32_t exception_code, uint32_t interrupt_mask,
     exception_print(&x, &y, "s4: 0x%08lX, s5: 0x%08lX, s6: 0x%08lX, s7: 0x%08lX", e->s4.u32, e->s5.u32, e->s6.u32, e->s7.u32);
     exception_print(&x, &y, "t8: 0x%08lX, t9: 0x%08lX, k0: 0x%08lX, k1: 0x%08lX", e->t8.u32, e->t9.u32, e->k0.u32, e->k1.u32);
     exception_print(&x, &y, "gp: 0x%08lX, sp: 0x%08lX, fp: 0x%08lX, ra: 0x%08lX\n", e->gp.u32, e->sp.u32, e->fp.u32, e->ra.u32);
-    exception_print(&x, &y, "0x%08lX: 0x%08lX = [%4s]\n", (uint32_t) (&SC64->VERSION), sc64_version, (char *) (&sc64_version));
-    exception_print(&x, &y, "------------------------------------------------------------------------\n");
+    exception_print(&x, &y, "0x%08lX: 0x%08lX = [%4s]", (uint32_t) (&SC64->VERSION), sc64_version, (char *) (&sc64_version));
+    exception_print(&x, &y, "%s\n", XSTR(__SC64_VERSION));
 
     if (exception_code == EXCEPTION_INTERRUPT) {
         if (interrupt_mask & INTERRUPT_MASK_TIMER) {
diff --git a/sw/n64/src/exception.h b/sw/n64/src/exception.h
index 49c0f74..6a75299 100644
--- a/sw/n64/src/exception.h
+++ b/sw/n64/src/exception.h
@@ -2,10 +2,17 @@
 #define EXCEPTION_H__
 
 
-#define EXCEPTION_TRIGGER(code) { asm volatile ("syscall %[c]\n" :: [c] "i" (code)); }
+#define TRIGGER_CODE_ERROR          (0)
+#define TRIGGER_CODE_ASSERT         (16)
 
-#define TRIGGER_CODE_ERROR              (0)
-#define TRIGGER_CODE_ASSERT             (16)
+#define EXCEPTION_TRIGGER(code)     { asm volatile ("syscall %[c]\n" :: [c] "i" (code)); }
+
+
+void exception_install (void);
+void exception_enable_interrupts (void);
+void exception_disable_interrupts (void);
+void exception_enable_watchdog (void);
+void exception_disable_watchdog (void);
 
 
 #endif
diff --git a/sw/n64/src/init.c b/sw/n64/src/init.c
index 231ee0c..84c3cee 100644
--- a/sw/n64/src/init.c
+++ b/sw/n64/src/init.c
@@ -1,4 +1,5 @@
-#include "sys.h"
+#include "exception.h"
+#include "io.h"
 #include "sc64.h"
 
 
@@ -6,5 +7,14 @@ void init (void) {
     uint32_t pifram = si_io_read((io32_t *) (&PIFRAM[0x3C]));
     si_io_write((io32_t *) (&PIFRAM[0x3C]), pifram | 0x08);
 
+    exception_install();
+    exception_enable_watchdog();
+    exception_enable_interrupts();
+
     sc64_init();
 }
+
+void deinit (void) {
+    exception_disable_interrupts();
+    exception_disable_watchdog();
+}
diff --git a/sw/n64/src/init.h b/sw/n64/src/init.h
new file mode 100644
index 0000000..d6c2dc2
--- /dev/null
+++ b/sw/n64/src/init.h
@@ -0,0 +1,9 @@
+#ifndef INIT_H__
+#define INIT_H__
+
+
+void init (void);
+void deinit (void);
+
+
+#endif
diff --git a/sw/n64/src/interrupt.c b/sw/n64/src/interrupt.c
index 721ede5..9ebc2f9 100644
--- a/sw/n64/src/interrupt.c
+++ b/sw/n64/src/interrupt.c
@@ -1,4 +1,4 @@
-#include "sc64.h"
+#include "io.h"
 
 
 void exception_interrupt_handler (uint32_t exception_code, uint32_t interrupt_mask) {
diff --git a/sw/n64/src/sys.c b/sw/n64/src/io.c
similarity index 93%
rename from sw/n64/src/sys.c
rename to sw/n64/src/io.c
index e54910b..d31f4f6 100644
--- a/sw/n64/src/sys.c
+++ b/sw/n64/src/io.c
@@ -1,4 +1,4 @@
-#include "sys.h"
+#include "io.h"
 
 
 uint32_t io_read (io32_t *address) {
diff --git a/sw/n64/src/sys.h b/sw/n64/src/io.h
similarity index 78%
rename from sw/n64/src/sys.h
rename to sw/n64/src/io.h
index 80975b1..625ed8e 100644
--- a/sw/n64/src/sys.h
+++ b/sw/n64/src/io.h
@@ -1,5 +1,5 @@
-#ifndef SYS_H__
-#define SYS_H__
+#ifndef IO_H__
+#define IO_H__
 
 
 #include <stddef.h>
@@ -15,47 +15,6 @@ typedef volatile uint32_t io32_t;
 #define UNCACHED(address)           ((typeof(address)) (((io32_t) (address)) | (0xA0000000UL)))
 
 
-#define C0_SR_IE                    (1 << 0)
-#define C0_SR_EXL                   (1 << 1)
-#define C0_SR_EXR                   (1 << 2)
-#define C0_SR_KSU0                  (1 << 3)
-#define C0_SR_KSU1                  (1 << 4)
-#define C0_SR_UX                    (1 << 5)
-#define C0_SR_SX                    (1 << 6)
-#define C0_SR_KX                    (1 << 7)
-#define C0_SR_IM0                   (1 << 8)
-#define C0_SR_IM1                   (1 << 9)
-#define C0_SR_IM2                   (1 << 10)
-#define C0_SR_IM3                   (1 << 11)
-#define C0_SR_IM4                   (1 << 12)
-#define C0_SR_IM5                   (1 << 13)
-#define C0_SR_IM6                   (1 << 14)
-#define C0_SR_IM7                   (1 << 15)
-#define C0_SR_DS_DE                 (1 << 16)
-#define C0_SR_DS_CE                 (1 << 17)
-#define C0_SR_DS_CH                 (1 << 18)
-#define C0_SR_DS_SR                 (1 << 20)
-#define C0_SR_DS_TS                 (1 << 21)
-#define C0_SR_DS_BEV                (1 << 22)
-#define C0_SR_DS_ITS                (1 << 24)
-#define C0_SR_RE                    (1 << 25)
-#define C0_SR_FR                    (1 << 26)
-#define C0_SR_RP                    (1 << 27)
-#define C0_SR_CU0                   (1 << 28)
-#define C0_SR_CU1                   (1 << 29)
-#define C0_SR_CU2                   (1 << 30)
-#define C0_SR_CU3                   (1 << 31)
-
-#define C0_CR_IP0                   (1 << 8)
-#define C0_CR_IP1                   (1 << 9)
-#define C0_CR_IP2                   (1 << 9)
-#define C0_CR_IP3                   (1 << 9)
-#define C0_CR_IP4                   (1 << 9)
-#define C0_CR_IP5                   (1 << 9)
-#define C0_CR_IP6                   (1 << 9)
-#define C0_CR_IP7                   (1 << 9)
-#define C0_CR_BD                    (1 << 31)
-
 typedef struct {
     io32_t DMEM[1024];
     io32_t IMEM[1024];
diff --git a/sw/n64/src/ipl2.S b/sw/n64/src/ipl2.S
new file mode 100644
index 0000000..e99d010
--- /dev/null
+++ b/sw/n64/src/ipl2.S
@@ -0,0 +1,15 @@
+.set noat
+.set noreorder
+
+.section .text.ipl2
+ipl2:
+    .global ipl2
+    lui $t5, 0xBFC0
+1:
+    lw $t0, 0x7FC($t5)
+    addiu $t5, $t5, 0x7C0
+    andi $t0, $t0, 0x80
+    bnel $t0, $zero, 1b
+    lui $t5, 0xBFC0
+    lw $t0, 0x24($t5)
+    lui $t3, 0xB000
diff --git a/sw/n64/src/main.c b/sw/n64/src/main.c
index 314f2c8..1f47747 100644
--- a/sw/n64/src/main.c
+++ b/sw/n64/src/main.c
@@ -13,10 +13,14 @@ void main (void) {
     sc64_get_info(&sc64_info);
 
     switch (sc64_info.boot_mode) {
-        case BOOT_MODE_MENU:
+        case BOOT_MODE_MENU_SD:
             storage_run_menu(STORAGE_BACKEND_SD, &boot_info, &sc64_info);
             break;
 
+        case BOOT_MODE_MENU_USB:
+            storage_run_menu(STORAGE_BACKEND_USB, &boot_info, &sc64_info);
+            break;
+
         case BOOT_MODE_ROM:
             boot_info.device_type = BOOT_DEVICE_TYPE_ROM;
             break;
@@ -25,10 +29,6 @@ void main (void) {
             boot_info.device_type = BOOT_DEVICE_TYPE_DD;
             break;
 
-        case BOOT_MODE_MENU_USB:
-            storage_run_menu(STORAGE_BACKEND_USB, &boot_info, &sc64_info);
-            break;
-
         default:
             error_display("Unknown boot mode selected [%d]", sc64_info.boot_mode);
             break;
diff --git a/sw/n64/src/regs.h b/sw/n64/src/regs.h
new file mode 100644
index 0000000..5782d59
--- /dev/null
+++ b/sw/n64/src/regs.h
@@ -0,0 +1,70 @@
+#ifndef REGS_H__
+#define REGS_H__
+
+
+#define HIT_INVALIDATE_I            ((4 << 2) | 0)
+
+
+#define C0_COUNT                    $9
+#define C0_COMPARE                  $11
+#define C0_STATUS                   $12
+#define C0_CAUSE                    $13
+#define C0_EPC                      $14
+
+
+#define C0_SR_IE                    (1 << 0)
+#define C0_SR_EXL                   (1 << 1)
+#define C0_SR_EXR                   (1 << 2)
+#define C0_SR_KSU0                  (1 << 3)
+#define C0_SR_KSU1                  (1 << 4)
+#define C0_SR_UX                    (1 << 5)
+#define C0_SR_SX                    (1 << 6)
+#define C0_SR_KX                    (1 << 7)
+#define C0_SR_IM0                   (1 << 8)
+#define C0_SR_IM1                   (1 << 9)
+#define C0_SR_IM2                   (1 << 10)
+#define C0_SR_IM3                   (1 << 11)
+#define C0_SR_IM4                   (1 << 12)
+#define C0_SR_IM5                   (1 << 13)
+#define C0_SR_IM6                   (1 << 14)
+#define C0_SR_IM7                   (1 << 15)
+#define C0_SR_DS_DE                 (1 << 16)
+#define C0_SR_DS_CE                 (1 << 17)
+#define C0_SR_DS_CH                 (1 << 18)
+#define C0_SR_DS_SR                 (1 << 20)
+#define C0_SR_DS_TS                 (1 << 21)
+#define C0_SR_DS_BEV                (1 << 22)
+#define C0_SR_DS_ITS                (1 << 24)
+#define C0_SR_RE                    (1 << 25)
+#define C0_SR_FR                    (1 << 26)
+#define C0_SR_RP                    (1 << 27)
+#define C0_SR_CU0                   (1 << 28)
+#define C0_SR_CU1                   (1 << 29)
+#define C0_SR_CU2                   (1 << 30)
+#define C0_SR_CU3                   (1 << 31)
+
+
+#define C0_CR_EC0                   (1 << 2)
+#define C0_CR_EC1                   (1 << 3)
+#define C0_CR_EC2                   (1 << 4)
+#define C0_CR_EC3                   (1 << 5)
+#define C0_CR_EC4                   (1 << 6)
+#define C0_CR_IP0                   (1 << 8)
+#define C0_CR_IP1                   (1 << 9)
+#define C0_CR_IP2                   (1 << 10)
+#define C0_CR_IP3                   (1 << 11)
+#define C0_CR_IP4                   (1 << 12)
+#define C0_CR_IP5                   (1 << 13)
+#define C0_CR_IP6                   (1 << 14)
+#define C0_CR_IP7                   (1 << 15)
+#define C0_CR_CE0                   (1 << 28)
+#define C0_CR_CE1                   (1 << 29)
+#define C0_CR_BD                    (1 << 31)
+
+#define C0_CR_EC_MASK               (C0_CR_EC4 | C0_CR_EC3 | C0_CR_EC2 | C0_CR_EC1 | C0_CR_EC0)
+#define C0_CR_EC_BIT                (2)
+#define C0_CR_IP_MASK               (C0_CR_IP7 | C0_CR_IP6 | C0_CR_IP5 | C0_CR_IP4 | C0_CR_IP3 | C0_CR_IP2 | C0_CR_IP1 | C0_CR_IP0)
+#define C0_CR_IP_BIT                (8)
+
+
+#endif
diff --git a/sw/n64/src/sc64.h b/sw/n64/src/sc64.h
index 9ca4e8d..2f9fe4f 100644
--- a/sw/n64/src/sc64.h
+++ b/sw/n64/src/sc64.h
@@ -5,7 +5,7 @@
 #include <stdbool.h>
 #include <stdint.h>
 #include <stdio.h>
-#include "sys.h"
+#include "io.h"
 
 
 #define SC64_CMD_CONFIG             ('C')
@@ -67,11 +67,11 @@ typedef enum {
 } tv_type_t;
 
 typedef enum {
-    BOOT_MODE_MENU = 0,
-    BOOT_MODE_ROM = 1,
-    BOOT_MODE_DDIPL = 2,
-    BOOT_MODE_DIRECT = 3,
-    BOOT_MODE_MENU_USB = 4,
+    BOOT_MODE_MENU_SD = 0,
+    BOOT_MODE_MENU_USB = 1,
+    BOOT_MODE_ROM = 2,
+    BOOT_MODE_DDIPL = 3,
+    BOOT_MODE_DIRECT = 4,
 } boot_mode_t;
 
 typedef struct {
diff --git a/sw/n64/src/startup.S b/sw/n64/src/startup.S
index 90e8dd2..476b06f 100644
--- a/sw/n64/src/startup.S
+++ b/sw/n64/src/startup.S
@@ -1,8 +1,3 @@
-#define STR(x)  #x
-#define XSTR(s) STR(s)
-#define VERSION XSTR(__SC64_VERSION)
-
-
 .section .text.rom_header
 header_pi_config:
     .word 0x80371240
@@ -22,8 +17,7 @@ header_crc:
     .org 0x20, 0x00
 header_text_info:
     .global header_text_info
-    .ascii "SummerLoader64 "
-    .ascii VERSION
+    .ascii "n64boot SummerCart64"
     .org 0x40, 0x00
 
 
@@ -39,9 +33,6 @@ entry_handler:
     la $gp, _gp
     la $sp, _sp
 
-    la $t0, exception_install
-    jalr $t0
-
     la $t0, init
     jalr $t0
 
@@ -50,19 +41,3 @@ entry_handler:
 
 loop:
     j loop
-
-
-.section .text.ipl2
-ipl2:
-    .global ipl2
-    .set noat
-    .set noreorder
-    lui $t5, 0xBFC0
-1:
-    lw $t0, 0x7FC($t5)
-    addiu $t5, $t5, 0x7C0
-    andi $t0, $t0, 0x80
-    bnel $t0, $zero, 1b
-    lui $t5, 0xBFC0
-    lw $t0, 0x24($t5)
-    lui $t3, 0xB000
diff --git a/sw/pc/sc64.py b/sw/pc/sc64.py
index 32f3020..97654c1 100644
--- a/sw/pc/sc64.py
+++ b/sw/pc/sc64.py
@@ -275,10 +275,10 @@ class SC64:
             return "Unknown"
         return {
             0: "Load menu from SD card",
-            1: "Load ROM from SDRAM through bootloader",
-            2: "Load DDIPL from SDRAM",
-            3: "Load ROM from SDRAM directly without bootloader",
-            4: "Load menu from USB",
+            1: "Load menu from USB",
+            2: "Load ROM from SDRAM",
+            3: "Load DDIPL from SDRAM",
+            4: "Load ROM from SDRAM directly without bootloader",
         }[mode]
 
 
@@ -723,7 +723,7 @@ class SC64ProgressBar:
 
 if __name__ == "__main__":
     parser = argparse.ArgumentParser(description="SummerCart64 one stop control center")
-    parser.add_argument("-b", metavar="boot_mode", default="1", required=False, help="set boot mode (0 - 3)")
+    parser.add_argument("-b", metavar="boot_mode", default="2", required=False, help="set boot mode (0 - 4)")
     parser.add_argument("-t", metavar="tv_type", default="3", required=False, help="set TV type (0 - 2)")
     parser.add_argument("-c", metavar="cic_seed", default="0xFFFF", required=False, help="set CIC seed")
     parser.add_argument("-s", metavar="save_type", default="0", required=False, help="set save type (0 - 6)")
@@ -780,7 +780,7 @@ if __name__ == "__main__":
                     os.remove(firmware_backup_file)
 
             if (not is_read):
-                if (boot_mode != 1):
+                if (boot_mode != 2):
                     print(f"Setting boot mode to [{sc64.get_boot_mode_label(boot_mode)}]")
                 sc64.set_boot_mode(boot_mode)
 
diff --git a/sw/riscv/src/cfg.c b/sw/riscv/src/cfg.c
index 5b00269..9423b8c 100644
--- a/sw/riscv/src/cfg.c
+++ b/sw/riscv/src/cfg.c
@@ -52,10 +52,11 @@ enum save_type {
 };
 
 enum boot_mode {
-    BOOT_MODE_MENU = 0,
-    BOOT_MODE_ROM = 1,
-    BOOT_MODE_DD = 2,
-    BOOT_MODE_DIRECT = 3,
+    BOOT_MODE_MENU_SD = 0,
+    BOOT_MODE_MENU_USB = 1,
+    BOOT_MODE_ROM = 2,
+    BOOT_MODE_DD = 3,
+    BOOT_MODE_DIRECT = 4,
 };
 
 
@@ -249,7 +250,7 @@ void cfg_init (void) {
 
     p.cic_seed = 0xFFFF;
     p.tv_type = 0x03;
-    p.boot_mode = BOOT_MODE_MENU;
+    p.boot_mode = BOOT_MODE_MENU_SD;
 }