rosalina: introduce bootdiag, tool to dump state of a process in early init

sysmodules/rosalina/include/bootdiag.h

@@ -0,0 +1,30 @@
+/*
+*   This file is part of Luma3DS
+*   Copyright (C) 2022  TuxSH
+*
+*   This program is free software: you can redistribute it and/or modify
+*   it under the terms of the GNU General Public License as published by
+*   the Free Software Foundation, either version 3 of the License, or
+*   (at your option) any later version.
+*
+*   This program is distributed in the hope that it will be useful,
+*   but WITHOUT ANY WARRANTY; without even the implied warranty of
+*   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+*   GNU General Public License for more details.
+*
+*   You should have received a copy of the GNU General Public License
+*   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*
+*   Additional Terms 7.b and 7.c of GPLv3 apply to this file:
+*       * Requiring preservation of specified reasonable legal notices or
+*         author attributions in that material or in the Appropriate Legal
+*         Notices displayed by works containing it.
+*       * Prohibiting misrepresentation of the origin of that material,
+*         or requiring that modified versions of such material be marked in
+*         reasonable ways as different from the original version.
+*/
+
+#pragma once
+#include "MyThread.h"
+
+MyThread *bootdiagCreateThread(void);

sysmodules/rosalina/source/bootdiag.c

@@ -0,0 +1,116 @@
+/*
+*   This file is part of Luma3DS
+*   Copyright (C) 2022  TuxSH
+*
+*   This program is free software: you can redistribute it and/or modify
+*   it under the terms of the GNU General Public License as published by
+*   the Free Software Foundation, either version 3 of the License, or
+*   (at your option) any later version.
+*
+*   This program is distributed in the hope that it will be useful,
+*   but WITHOUT ANY WARRANTY; without even the implied warranty of
+*   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+*   GNU General Public License for more details.
+*
+*   You should have received a copy of the GNU General Public License
+*   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*
+*   Additional Terms 7.b and 7.c of GPLv3 apply to this file:
+*       * Requiring preservation of specified reasonable legal notices or
+*         author attributions in that material or in the Appropriate Legal
+*         Notices displayed by works containing it.
+*       * Prohibiting misrepresentation of the origin of that material,
+*         or requiring that modified versions of such material be marked in
+*         reasonable ways as different from the original version.
+*/
+
+#include <3ds.h>
+#include "MyThread.h"
+#include "ifile.h"
+#include "fmt.h"
+
+#ifdef  BOOTDIAG_ENABLED
+
+static MyThread bootdiagThread;
+static u8 ALIGN(0x1000) bootdiagThreadStack[0x1000];
+
+#define BOOTDIAG_WAIT_TIME      (2000 * 1000 * 1000u) // 2 seconds
+#define BOOTDIAG_PID            2u                    // PM
+#define BOOTDIAG_DUMP_TO_FILE   0
+
+static int bootdiagDumpThread(char *buf, Handle debug, u32 tid)
+{
+    ThreadContext ctx;
+    if (R_FAILED(svcGetDebugThreadContext(&ctx, debug, tid, THREADCONTEXT_CONTROL_ALL)))
+        return 0;
+
+    s64 dummy;
+    u32 mask = 0xFF;
+    svcGetDebugThreadParam(&dummy, &mask, debug, tid, DBGTHREAD_PARAMETER_SCHEDULING_MASK_LOW);
+
+    return sprintf(buf, "Thread %lu -- PC=%08lx LR=%08lx R0=%08lx sched=%lu\n", tid, ctx.cpu_registers.pc, ctx.cpu_registers.lr, ctx.cpu_registers.r[0], mask);
+}
+
+static int bootdiagDumpProcess(char *buf, u32 pid)
+{
+    Handle debug = 0;
+    int n = 0;
+
+    if (R_FAILED(svcDebugActiveProcess(&debug, pid)))
+        __builtin_trap();
+
+    while (svcWaitSynchronization(debug, 500 * 1000 * 1000) == 0)
+    {
+        DebugEventInfo info;
+        if (R_FAILED(svcGetProcessDebugEvent(&info, debug)))
+            break;
+
+        if (info.type == DBGEVENT_ATTACH_THREAD)
+            n += bootdiagDumpThread(buf + n, debug, info.thread_id);
+
+        if (info.flags & 1)
+            svcContinueDebugEvent(debug, 0);
+    }
+
+    svcCloseHandle(debug);
+    return n;
+}
+
+static void bootdiagThreadMain(void)
+{
+    char buf[512];
+
+    svcSleepThread(BOOTDIAG_WAIT_TIME);
+    int n = bootdiagDumpProcess(buf, BOOTDIAG_PID);
+
+#if BOOTDIAG_DUMP_TO_FILE
+    IFile file;
+    FS_ArchiveID archiveId = ARCHIVE_SDMC;
+
+    if (R_FAILED(fsInit())) __builtin_trap();
+
+    IFile_Open(&file, archiveId, fsMakePath(PATH_EMPTY, ""), fsMakePath(PATH_ASCII, "/luma/bootdiag.txt"), FS_OPEN_CREATE | FS_OPEN_WRITE);
+    u64 ttl = 0;
+    IFile_Write(file, &ttl, buf, (u32)n, 0);
+    IFile_Close(&file);
+
+    fsExit();
+#else
+    (void)n;
+    *(volatile char *)buf;
+    __builtin_trap(); // use stack dump to extract info
+#endif
+}
+
+MyThread *bootdiagCreateThread(void)
+{
+    if(R_FAILED(MyThread_Create(&bootdiagThread, bootdiagThreadMain, bootdiagThreadStack, sizeof(bootdiagThreadStack), 18, 0)))
+        svcBreak(USERBREAK_PANIC);
+    return &bootdiagThread;
+}
+#endif
+
+MyThread *bootdiagCreateThread(void)
+{
+    return NULL;
+}

sysmodules/rosalina/source/main.c

@@ -41,6 +41,7 @@
 #include "input_redirection.h"
 #include "minisoc.h"
 #include "draw.h"
+#include "bootdiag.h"
 
 #include "task_runner.h"
 
@@ -264,6 +265,7 @@ int main(void)
     MyThread *menuThread = menuCreateThread();
     MyThread *taskRunnerThread = taskRunnerCreateThread();
     MyThread *errDispThread = errDispCreateThread();
+    bootdiagCreateThread();
 
     if (R_FAILED(ServiceManager_Run(services, notifications, NULL)))
         svcBreak(USERBREAK_PANIC);