lolserial improvements

allow debug output to be suspended, drop assembly version

stage2/debug.c

@@ -1,15 +0,0 @@
-#ifdef LOLSERIAL_DEBUG
-
-extern void lolserial_lprint(char *str, int len);
-
-void DEBUG(char *fmt, ...)
-{
-    char str[256];
-    va_list va;
-    va_start(va, fmt);
-    vsnprintf(str, sizeof(str), fmt, va);
-    lolserial_lprint(str, sizeof(str));
-    va_end(va);
-}
-
-#endif /* LOLSERIAL_DEBUG */

stage2/debug.h

@@ -16,11 +16,12 @@
 #define __DEBUG_H__
 
 #include "types.h"
+#include "stdio.h"
 
-#ifndef LOLSERIAL_DEBUG
+#ifndef ENABLE_DEBUG
 static inline void DEBUG(char *fmt, ...) {}
 #else
-void DEBUG(char *fmt, ...);
+#define DEBUG(...) printf(__VA_ARGS__)
 #endif
 
 

stage2/lolserial.c

@@ -0,0 +1,78 @@
+#ifdef LOLSERIAL_DEBUG
+
+#include "lolserial.h"
+#include "gpio.h"
+#include "utils.h"
+#include "latte.h"
+#include <sys/iosupport.h>
+#include <string.h>
+
+#define LOLSERIAL_WAIT_TICKS    200
+
+static int enable = 1;
+static char suspend_buf[4096];
+static int suspend_len = 0;
+
+/* lolserial string output, now not in assembly... */
+static void lolserial_lprint(const char *str, int len)
+{
+    /* setup output pin */
+    clear32(LT_GPIO_OWNER, GP_SENSORBAR);
+    set32(LT_GPIO_ENABLE, GP_SENSORBAR);
+    set32(LT_GPIO_DIR, GP_SENSORBAR);
+    set32(LT_GPIO_OUT, GP_SENSORBAR);
+
+    /* loop until null terminator or string end */
+    for (const char *end = str + len; *str && (str != end); str++) {
+        for (u32 bits = 0x200 | (*str << 1); bits; bits >>= 1) {
+            /* set bit value */
+            mask32(LT_GPIO_OUT, GP_SENSORBAR, (bits & 1) ? GP_SENSORBAR : 0);
+
+            /* wait ticks for bit */
+            u32 now = read32(LT_TIMER), then = now + LOLSERIAL_WAIT_TICKS;
+            for (; then < now; now = read32(LT_TIMER)); /* wait overflow */
+            for (; now < then; now = read32(LT_TIMER)); /* wait */
+        }
+    }
+}
+
+/* lolserial is slow, for timing critical tasks it might change
+ * the outcome; as a workaround, output can be suspended and
+ * printed out at a later point in time */
+void lolserial_suspend(void)
+{
+    memset(suspend_buf, 0, sizeof(suspend_buf));
+    suspend_len = 0;
+    enable = 0;
+}
+
+void lolserial_resume(void)
+{
+    enable = 1;
+    lolserial_lprint(suspend_buf, suspend_len);
+}
+
+/* devoptab output function */
+static ssize_t lolserial_write(struct _reent *r, void *fd, const char *ptr, size_t len)
+{
+    if (enable) {
+        lolserial_lprint(ptr, len);
+    } else {
+        for(size_t i = 0; (i < len) && (suspend_len < sizeof(suspend_buf)); i++) 
+            suspend_buf[suspend_len++] = ptr[i];
+    }
+
+    return len;
+}
+
+/* register lolserial devoptab */
+void lolserial_init() {
+    static devoptab_t lolserial_dotab = {
+        .name = "lolserial",
+        .write_r = &lolserial_write,
+    };
+    devoptab_list[STD_OUT] = &lolserial_dotab;
+    devoptab_list[STD_ERR] = &lolserial_dotab;
+}
+
+#endif /* LOLSERIAL_DEBUG */

stage2/lolserial.h

@@ -0,0 +1,19 @@
+#ifndef __LOLSERIAL_H__
+#define __LOLSERIAL_H__
+
+#ifdef LOLSERIAL_DEBUG
+
+void lolserial_init();
+void lolserial_suspend(void);
+void lolserial_resume(void);
+
+#else
+
+#define lolserial_init()
+#define lolserial_suspend()
+#define lolserial_resume()
+
+#endif /* LOLSERIAL_DEBUG */
+
+#endif /* __LOLSERIAL_H__ */
+

stage2/lolserial_asm.S

@@ -1,103 +0,0 @@
-/*
- *  minute - a port of the "mini" IOS replacement for the Wii U.
- *
-*	Copyright (C) 2021          Roberto Van Eeden <rwrr0644@gmail.com>
- *
- *  This code is licensed to you under the terms of the GNU GPL, version 2;
- *  see file COPYING or http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt
- */
-
-#ifdef LOLSERIAL_DEBUG
-
-#include "latte.h"
-
-.arm
-
-.globl lolserial_print
-.globl lolserial_lprint
-
-.section .text
-
-/*
- * the number of timer ticks to wait
- * each bit; might need manual adjustment
- * for particoular serial adapters, usually
- * the stable value is in the +5/-5 range
- */
-
-.equ LOLSERIAL_WAIT_TICKS, 200
-.equ GP_SENSORBAR, 0x00000100
-
-@ arg:r0 string address
-lolserial_print:
-    mov r1, #-1
-
-@ arg:r0 string address
-@ arg:r1 max length
-lolserial_lprint:
-    push {r4-r5}
-    add r1, r0                                          @ end address in r1
-    ldr r5, =LT_REG_BASE                                @ latte registers base in r5
-
-    @ clear32(LT_GPIO_OWNER, GP_SENSORBAR)
-    ldr r2, [r5, #0x0FC]
-    bic r2, r2, #GP_SENSORBAR
-    str r2, [r5, #0x0FC]
-
-    @ set32(LT_GPIO_ENABLE, GP_SENSORBAR)
-    ldr r2, [r5, #0x0DC]
-    orr r2, r2, #GP_SENSORBAR
-    str r2, [r5, #0x0DC]
-
-    @ set32(LT_GPIO_DIR, GP_SENSORBAR)
-    ldr r2, [r5, #0x0E4]
-    orr r2, r2, #GP_SENSORBAR
-    str r2, [r5, #0x0E4]
-
-    @ set32(LT_GPIO_OUT, GP_SENSORBAR)
-    ldr r2, [r5, #0x0E0]
-    orr r2, r2, #GP_SENSORBAR
-    str r2, [r5, #0x0E0]
-
-    lolserial_send_string_loop:
-        cmp r0, r1                                      @ ensure end address was not reached
-        ldrneb r3, [r0], #1                             @   load cur char in r3, increment r0 string ptr
-        cmpne r3, #0                                    @   check for string null termination
-        beq lolserial_send_string_end
-
-        @ r3: bits to send (serial end bit, data byte, serial start bit)
-        @ r3 = (1 << 9) | (r3:chr << 1) | (0 << 0)
-        lsl r3, #1
-        orr r3, #0x200
-
-        @ loop over bits to send
-        lolserial_send_char_loop:
-            @ mask32(LT_GPIO_OUT, GP_SENSORBAR, bit ? GP_SENSORBAR : 0)
-            tst r3, #1
-            ldr r2, [r5, #0x0E0]
-            biceq r2, #GP_SENSORBAR
-            orrne r2, #GP_SENSORBAR
-            str r2, [r5, #0x0E0]
-
-            @ wait for LOLSERIAL_WAIT_TICKS timer ticks
-            ldr r2, [r5, #0x010]                        @ r2: current ticks
-            adds r4, r2, #LOLSERIAL_WAIT_TICKS          @ r4: wait time end
-            timer_wait_overflow_loop:
-                cmp r4, r2
-                ldr r2, [r5, #0x010]
-                blo timer_wait_overflow_loop
-            timer_wait_loop:
-                cmp r4, r2
-                ldr r2, [r5, #0x010]
-                bhi timer_wait_loop
-
-            lsrs r3, #1                                 @ go to next bit
-            bne lolserial_send_char_loop                @ unless r3 is 0 (end bit sent)
-        
-        b lolserial_send_string_loop
-    lolserial_send_string_end:
-
-    pop {r4-r5}
-    bx lr
-
-#endif /* LOLSERIAL_DEBUG */

stage2/main.c

@@ -31,6 +31,8 @@
 #include "nand.h"
 #include "isfs/isfs.h"
 #include "ancast.h"
+#include "debug.h"
+#include "lolserial.h"
 
 u32 load_payload_sd(void)
 {
@@ -108,18 +110,32 @@ error_open:
 u32 _main(void)
 {
     u32 vector = 0;
+
+    lolserial_init();
+    DEBUG("isfshax start\n");
+
     //mem_initialize();
     irq_initialize();
     crypto_read_otp();
     nand_initialize();
 
     /* repair isfshax superblocks ecc errors, if present */
+    DEBUG("isfshax_refresh\n");
     isfshax_refresh();
 
     /* attempt to load the payload from SD, then NAND */
+    DEBUG("load_payload_sd\n");
+    lolserial_suspend();
     vector = load_payload_sd();
-    if (!vector)
+    lolserial_resume();
+
+    if (!vector) {
+        DEBUG("load_payload_nand\n");
+        lolserial_suspend();
         vector = load_payload_nand();
+        lolserial_resume();
+    }
+    DEBUG("vector: %08lX\n", vector);
 
     nand_deinitialize();
     irq_shutdown();