Fix watchpoints handling (huge thanks to @Nanquitas)

k11_extension/include/debug.h

@@ -0,0 +1,39 @@
+/*
+*   This file is part of Luma3DS
+*   Copyright (C) 2016-2017 Aurora Wright, 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 "types.h"
+#include "globals.h"
+#include "kernel.h"
+#include "utils.h"
+
+extern KRecursiveLock dbgParamsLock;
+extern u32 dbgParamWatchpointId, dbgParamDVA, dbgParamWCR, dbgParamContextId;
+
+KSchedulableInterruptEvent *enableMonitorModeDebugging(KBaseInterruptEvent *this, u32 interruptID);
+KSchedulableInterruptEvent *disableWatchpoint(KBaseInterruptEvent *this, u32 interruptID);
+KSchedulableInterruptEvent *setWatchpointWithContextId(KBaseInterruptEvent *this, u32 interruptID);

k11_extension/source/debug.c

@@ -0,0 +1,147 @@
+/*
+*   This file is part of Luma3DS
+*   Copyright (C) 2016-2017 Aurora Wright, 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 "debug.h"
+#include "memory.h"
+#include "synchronization.h"
+
+KRecursiveLock dbgParamsLock = { NULL };
+u32 dbgParamWatchpointId, dbgParamDVA, dbgParamWCR, dbgParamContextId;
+
+KSchedulableInterruptEvent *enableMonitorModeDebugging(KBaseInterruptEvent *this UNUSED, u32 interruptID UNUSED)
+{
+    coreBarrier();
+
+    u32 DSCR;
+    __asm__ __volatile__("mrc p14, 0, %[val], c0, c1, 0" : [val] "=r" (DSCR));
+    DSCR |= 0x8000;
+    __asm__ __volatile__("mcr p14, 0, %[val], c0, c1, 0" :: [val] "r" (DSCR));
+
+    __dsb();
+    coreBarrier();
+
+    return NULL;
+}
+
+static void disableWatchpoint0(void)
+{
+    u32 control;
+
+    // WCR0
+    __asm__ __volatile__("mrc p14, 0, %[val], c0, c0, 7" : [val] "=r" (control));
+    control &= ~1;
+    __asm__ __volatile__("mcr p14, 0, %[val], c0, c0, 7" :: [val] "r" (control));
+
+    // BCR4
+    __asm__ __volatile__("mrc p14, 0, %[val], c0, c4, 5" : [val] "=r" (control));
+    control &= ~1;
+    __asm__ __volatile__("mcr p14, 0, %[val], c0, c4, 5" :: [val] "r" (control));
+}
+
+static void disableWatchpoint1(void)
+{
+    u32 control;
+
+    // WCR1
+    __asm__ __volatile__("mrc p14, 0, %[val], c0, c1, 7" : [val] "=r" (control));
+    control &= ~1;
+    __asm__ __volatile__("mcr p14, 0, %[val], c0, c1, 7" :: [val] "r" (control));
+
+    // BCR5
+    __asm__ __volatile__("mrc p14, 0, %[val], c0, c5, 5" : [val] "=r" (control));
+    control &= ~1;
+    __asm__ __volatile__("mcr p14, 0, %[val], c0, c5, 5" :: [val] "r" (control));
+}
+
+KSchedulableInterruptEvent *disableWatchpoint(KBaseInterruptEvent *this UNUSED, u32 interruptID UNUSED)
+{
+    coreBarrier();
+
+    if(dbgParamWatchpointId == 0)
+        disableWatchpoint0();
+    else
+        disableWatchpoint1();
+
+    __dsb();
+    coreBarrier();
+
+    return NULL;
+}
+
+static void setWatchpoint0WithContextId(u32 DVA, u32 WCR, u32 contextId)
+{
+    // http://infocenter.arm.com/help/topic/com.arm.doc.ddi0360f/CEGCFFDF.html
+    u32 BCR =
+            (1   << 21) | /* compare with context ID */
+            (1   << 20) | /* linked (with a WRP in our case) */
+            (0xf <<  5) | /* byte address select, +0 to +3 as mandated when linking with a WRP */
+            (3   <<  1) | /* either privileged modes or user mode, as mandated when linking with a WRP */
+            (1   <<  0) ; /* enabled */
+
+    disableWatchpoint0();
+
+    __asm__ __volatile__("mcr p14, 0, %[val], c0, c0, 6" :: [val] "r" (DVA));
+    __asm__ __volatile__("mcr p14, 0, %[val], c0, c4, 4" :: [val] "r" (contextId));
+    __asm__ __volatile__("mcr p14, 0, %[val], c0, c0, 7" :: [val] "r" (WCR));
+    __asm__ __volatile__("mcr p14, 0, %[val], c0, c4, 5" :: [val] "r" (BCR));
+
+    __asm__ __volatile__("mcr p15, 0, %[val], c7, c10, 5" :: [val] "r" (0) : "memory"); // DMB
+}
+
+static void setWatchpoint1WithContextId(u32 DVA, u32 WCR, u32 contextId)
+{
+    // http://infocenter.arm.com/help/topic/com.arm.doc.ddi0360f/CEGCFFDF.html
+    u32 BCR =
+            (1   << 21) | /* compare with context ID */
+            (1   << 20) | /* linked (with a WRP in our case) */
+            (0xf <<  5) | /* byte address select, +0 to +3 as mandated when linking with a WRP */
+            (3   <<  1) | /* either privileged modes or user mode, as mandated when linking with a WRP */
+            (1   <<  0) ; /* enabled */
+
+    disableWatchpoint1();
+
+    __asm__ __volatile__("mcr p14, 0, %[val], c0, c1, 6" :: [val] "r" (DVA));
+    __asm__ __volatile__("mcr p14, 0, %[val], c0, c5, 4" :: [val] "r" (contextId));
+    __asm__ __volatile__("mcr p14, 0, %[val], c0, c1, 7" :: [val] "r" (WCR));
+    __asm__ __volatile__("mcr p14, 0, %[val], c0, c5, 5" :: [val] "r" (BCR));
+
+    __asm__ __volatile__("mcr p15, 0, %[val], c7, c10, 5" :: [val] "r" (0) : "memory"); // DMB
+}
+
+KSchedulableInterruptEvent *setWatchpointWithContextId(KBaseInterruptEvent *this UNUSED, u32 interruptID UNUSED)
+{
+    coreBarrier();
+
+    if(dbgParamWatchpointId == 0)
+        setWatchpoint0WithContextId(dbgParamDVA, dbgParamWCR, dbgParamContextId);
+    else
+        setWatchpoint1WithContextId(dbgParamDVA, dbgParamWCR, dbgParamContextId);
+
+    __dsb();
+    coreBarrier();
+
+    return NULL;
+}

k11_extension/source/svc/KernelSetState.c

@@ -27,6 +27,7 @@
 #include "svc/KernelSetState.h"
 #include "synchronization.h"
 #include "ipc.h"
+#include "debug.h"
 #include "memory.h"
 
 #define MAX_DEBUG 3
@@ -142,7 +143,41 @@ Result KernelSetStateHook(u32 type, u32 varg1, u32 varg2, u32 varg3)
             res = SetSyscallDebugEventMask(varg1, (bool)varg2, (const u32 *)varg3);
             break;
         }
-
+        case 0x10003:
+        {
+            executeFunctionOnCores(enableMonitorModeDebugging, 0xF, 0);
+            break;
+        }
+        case 0x10004:
+        {
+            KRecursiveLock__Lock(&dbgParamsLock);
+            dbgParamWatchpointId = varg1;
+            executeFunctionOnCores(disableWatchpoint, 0xF, 0);
+            KRecursiveLock__Unlock(&dbgParamsLock);
+            break;
+        }
+        case 0x10005:
+        {
+            KRecursiveLock__Lock(&dbgParamsLock);
+            dbgParamWatchpointId = 0;
+            dbgParamDVA = varg1;
+            dbgParamWCR = varg2;
+            dbgParamContextId = varg3;
+            executeFunctionOnCores(setWatchpointWithContextId, 0xF, 0);
+            KRecursiveLock__Unlock(&dbgParamsLock);
+            break;
+        }
+        case 0x10006:
+        {
+            KRecursiveLock__Lock(&dbgParamsLock);
+            dbgParamWatchpointId = 1;
+            dbgParamDVA = varg1;
+            dbgParamWCR = varg2;
+            dbgParamContextId = varg3;
+            executeFunctionOnCores(setWatchpointWithContextId, 0xF, 0);
+            KRecursiveLock__Unlock(&dbgParamsLock);
+            break;
+        }
         default:
         {
             res = KernelSetState(type, varg1, varg2, varg3);

sysmodules/rosalina/source/gdb/watchpoints.c

@@ -55,92 +55,6 @@ typedef struct WatchpointManager
 
 static WatchpointManager manager;
 
-static void K_EnableMonitorModeDebugging(void)
-{
-    __asm__ __volatile__("cpsid aif");
-
-    u32 DSCR;
-    __asm__ __volatile__("mrc p14, 0, %[val], c0, c1, 0" : [val] "=r" (DSCR));
-    DSCR |= 0x8000;
-    __asm__ __volatile__("mcr p14, 0, %[val], c0, c1, 0" :: [val] "r" (DSCR));
-}
-
-static void K_DisableWatchpoint(u32 id)
-{
-    u32 control;
-
-    __asm__ __volatile__("cpsid aif");
-
-    if(id == 0)
-    {
-        // WCR0
-        __asm__ __volatile__("mrc p14, 0, %[val], c0, c0, 7" : [val] "=r" (control));
-        control &= ~1;
-        __asm__ __volatile__("mcr p14, 0, %[val], c0, c0, 7" :: [val] "r" (control));
-
-        // BCR4
-        __asm__ __volatile__("mrc p14, 0, %[val], c0, c4, 5" : [val] "=r" (control));
-        control &= ~1;
-        __asm__ __volatile__("mcr p14, 0, %[val], c0, c4, 5" :: [val] "r" (control));
-    }
-    else if(id == 1)
-    {
-        // WCR1
-        __asm__ __volatile__("mrc p14, 0, %[val], c0, c1, 7" : [val] "=r" (control));
-        control &= ~1;
-        __asm__ __volatile__("mcr p14, 0, %[val], c0, c1, 7" :: [val] "r" (control));
-
-        // BCR5
-        __asm__ __volatile__("mrc p14, 0, %[val], c0, c5, 5" : [val] "=r" (control));
-        control &= ~1;
-        __asm__ __volatile__("mcr p14, 0, %[val], c0, c5, 5" :: [val] "r" (control));
-    }
-}
-
-static void K_SetWatchpoint0WithContextId(u32 DVA, u32 WCR, u32 contextId)
-{
-    // http://infocenter.arm.com/help/topic/com.arm.doc.ddi0360f/CEGCFFDF.html
-    u32 BCR =
-            (1   << 21) | /* compare with context ID */
-            (1   << 20) | /* linked (with a WRP in our case) */
-            (0xf <<  5) | /* byte address select, +0 to +3 as mandated when linking with a WRP */
-            (3   <<  1) | /* either privileged modes or user mode, as mandated when linking with a WRP */
-            (1   <<  0) ; /* enabled */
-
-    __asm__ __volatile__("cpsid aif");
-
-    K_DisableWatchpoint(0);
-
-    __asm__ __volatile__("mcr p14, 0, %[val], c0, c0, 6" :: [val] "r" (DVA));
-    __asm__ __volatile__("mcr p14, 0, %[val], c0, c4, 4" :: [val] "r" (contextId));
-    __asm__ __volatile__("mcr p14, 0, %[val], c0, c0, 7" :: [val] "r" (WCR));
-    __asm__ __volatile__("mcr p14, 0, %[val], c0, c4, 5" :: [val] "r" (BCR));
-
-    __asm__ __volatile__("mcr p15, 0, %[val], c7, c10, 5" :: [val] "r" (0) : "memory"); // DMB
-}
-
-static void K_SetWatchpoint1WithContextId(u32 DVA, u32 WCR, u32 contextId)
-{
-    // http://infocenter.arm.com/help/topic/com.arm.doc.ddi0360f/CEGCFFDF.html
-    u32 BCR =
-            (1   << 21) | /* compare with context ID */
-            (1   << 20) | /* linked (with a WRP in our case) */
-            (0xf <<  5) | /* byte address select, +0 to +3 as mandated when linking with a WRP */
-            (3   <<  1) | /* either privileged modes or user mode, as mandated when linking with a WRP */
-            (1   <<  0) ; /* enabled */
-
-    __asm__ __volatile__("cpsid aif");
-
-    K_DisableWatchpoint(1);
-
-    __asm__ __volatile__("mcr p14, 0, %[val], c0, c1, 6" :: [val] "r" (DVA));
-    __asm__ __volatile__("mcr p14, 0, %[val], c0, c5, 4" :: [val] "r" (contextId));
-    __asm__ __volatile__("mcr p14, 0, %[val], c0, c1, 7" :: [val] "r" (WCR));
-    __asm__ __volatile__("mcr p14, 0, %[val], c0, c5, 5" :: [val] "r" (BCR));
-
-    __asm__ __volatile__("mcr p15, 0, %[val], c7, c10, 5" :: [val] "r" (0) : "memory"); // DMB
-}
-
 void GDB_ResetWatchpoints(void)
 {
     static bool lockInitialized = false;
@@ -151,9 +65,9 @@ void GDB_ResetWatchpoints(void)
     }
     RecursiveLock_Lock(&watchpointManagerLock);
 
-    svcCustomBackdoor(K_EnableMonitorModeDebugging);
+    svcKernelSetState(0x10003); // enable monitor mode debugging
-    svcCustomBackdoor(K_DisableWatchpoint, 0);
+    svcKernelSetState(0x10004, 0); // disable watchpoint 0
-    svcCustomBackdoor(K_DisableWatchpoint, 1);
+    svcKernelSetState(0x10004, 1); // disable watchpoint 1
 
     memset(&manager, 0, sizeof(WatchpointManager));
 
@@ -192,7 +106,7 @@ int GDB_AddWatchpoint(GDBContext *ctx, u32 address, u32 size, WatchpointKind kin
 
     if(R_SUCCEEDED(r))
     {
-        svcCustomBackdoor(id == 0 ? K_SetWatchpoint0WithContextId : K_SetWatchpoint1WithContextId, address, WCR, (u32)out);
+        svcKernelSetState(id == 0 ? 0x10005 : 0x10006, address, WCR, (u32)out); // set watchpoint
         Watchpoint *watchpoint = &manager.watchpoints[id];
         manager.total++;
         watchpoint->address = address;
@@ -224,7 +138,7 @@ int GDB_RemoveWatchpoint(GDBContext *ctx, u32 address, WatchpointKind kind)
     }
     else
     {
-        svcCustomBackdoor(K_DisableWatchpoint, id);
+        svcKernelSetState(0x10004, id); // disable watchpoint
 
         memset(&manager.watchpoints[id], 0, sizeof(Watchpoint));
         manager.total--;