From 86cc722477a3e462b1f0ac4442fec7e79596745d Mon Sep 17 00:00:00 2001
From: Ingo Weinhold <ingo_weinhold@gmx.de>
Date: Wed, 2 Mar 2005 00:05:02 +0000
Subject: [PATCH] * DR3 is used for holding the pointer to the current struct
 thread*, so   we only have 3 debug registers available for
 break-/watchpoints. * Added definitions for debug status register DR6.
 Reordered DR7 defs to   ascending order. Added definitions for the EFLAGS
 flags we need. * Added arch_thread_debug_info structure and related
 definitions.

git-svn-id: file:///srv/svn/repos/haiku/trunk/current@11525 a95241bf-73f2-0310-859d-f6bbb57e9c96
---
 .../kernel/arch/x86/arch_user_debugger.h      | 88 ++++++++++++++-----
 1 file changed, 68 insertions(+), 20 deletions(-)

diff --git a/headers/private/kernel/arch/x86/arch_user_debugger.h b/headers/private/kernel/arch/x86/arch_user_debugger.h
index eb2d077317..6bf00f45e2 100644
--- a/headers/private/kernel/arch/x86/arch_user_debugger.h
+++ b/headers/private/kernel/arch/x86/arch_user_debugger.h
@@ -6,8 +6,23 @@
 #define _KERNEL_ARCH_X86_USER_DEBUGGER_H
 
 // number of breakpoints the CPU supports
+// Actually it supports 4, but DR3 is used to hold the struct thread*.
 enum {
-	X86_BREAKPOINT_COUNT = 4,
+	X86_BREAKPOINT_COUNT = 3,
+};
+
+// debug status register DR6
+enum {
+	X86_DR6_B0			= 0,	// breakpoint condition detected
+	X86_DR6_B1			= 1,	//
+	X86_DR6_B2			= 2,	//
+	X86_DR6_B3			= 3,	//
+	X86_DR6_BD			= 13,	// debug register access detected
+	X86_DR6_BS			= 14,	// single step
+	X86_DR6_BT			= 15,	// task switch
+
+	X86_DR6_BREAKPOINT_MASK	= (1 << X86_DR6_B0) | (1 << X86_DR6_B1)
+								| (1 << X86_DR6_B2) | (1 << X86_DR6_B3),
 };
 
 // debug control register DR7 layout:
@@ -18,32 +33,38 @@ enum {
 // 0  0  GD 0  0  1  GE LE G3 L3 G2 L2 G1 L1 G0 L0
 //
 enum {
-	X86_DR7_LEN3_LSB	= 30,	// breakpoints len and type
-	X86_DR7_RW3_LSB	= 28,		//
-	X86_DR7_LEN2_LSB	= 26,	//
-	X86_DR7_RW2_LSB	= 24,		//
-	X86_DR7_LEN1_LSB	= 22,	//
-	X86_DR7_RW1_LSB	= 20,		//
-	X86_DR7_LEN0_LSB	= 18,	//
-	X86_DR7_RW0_LSB	= 16,		//
-	X86_DR7_GD		= 13,		// general detect enable: disallows debug
+	X86_DR7_L0			= 0,	// local/global breakpoints enable
+	X86_DR7_G0			= 1,	//
+	X86_DR7_L1			= 2,	//
+	X86_DR7_G1			= 3,	//
+	X86_DR7_L2			= 4,	//
+	X86_DR7_G2			= 5,	//
+	X86_DR7_L3			= 6,	//
+	X86_DR7_G3			= 7,	//
+	X86_DR7_LE			= 8,	// local/global exact breakpoint
+	X86_DR7_GE			= 9,	//
+	X86_DR7_GD			= 13,	// general detect enable: disallows debug
 								// register access
-	X86_DR7_GE		= 9,		// global/local exact breakpoint
-	X86_DR7_LE		= 8,		//
-	X86_DR7_G3		= 7,		// global/local breakpoints enable
-	X86_DR7_L3		= 6,		//
-	X86_DR7_G2		= 5,		//
-	X86_DR7_L2		= 4,		//
-	X86_DR7_G1		= 3,		//
-	X86_DR7_L1		= 2,		//
-	X86_DR7_G0		= 1,		//
-	X86_DR7_L0		= 0,		//
+	X86_DR7_RW0_LSB		= 16,	// breakpoints type and len
+	X86_DR7_LEN0_LSB	= 18,	//
+	X86_DR7_RW1_LSB		= 20,	//
+	X86_DR7_LEN1_LSB	= 22,	//
+	X86_DR7_RW2_LSB		= 24,	//
+	X86_DR7_LEN2_LSB	= 26,	//
+	X86_DR7_RW3_LSB		= 28,	//
+	X86_DR7_LEN3_LSB	= 30,	//
 
 	X86_BREAKPOINTS_DISABLED_DR7
 		= (1 << 10) | (1 << X86_DR7_GE) | (1 << X86_DR7_LE),
 		// all breakpoints disabled
 };
 
+// the EFLAGS flags we need
+enum {
+	X86_EFLAGS_TF	= 8,		// trap flag (single stepping)
+	X86_EFLAGS_RF	= 16,		// resume flag (skips instruction breakpoint)
+};
+
 // x86 breakpoint types
 enum {
 	X86_INSTRUCTION_BREAKPOINT		= 0x0,
@@ -59,6 +80,11 @@ enum {
 	X86_BREAKPOINT_LENGTH_4	= 0x3,
 };
 
+// thread debug flags
+enum {
+	X86_THREAD_DEBUG_DR7_SET			= 0x01,
+};
+
 struct arch_breakpoint {
 	void	*address;	// NULL, if deactivated
 	uint32	type;		// one of the architecture types above
@@ -71,4 +97,26 @@ struct arch_team_debug_info {
 	uint32					dr7;	// debug control register DR7
 };
 
+struct arch_thread_debug_info {
+	uint32	flags;
+};
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct iframe;
+struct thread;
+
+extern void i386_init_user_debug_at_kernel_exit(struct iframe *frame);
+extern void i386_exit_user_debug_at_kernel_entry();
+extern void i386_reinit_user_debug_after_context_switch(struct thread *thread);
+
+extern int i386_handle_debug_exception(struct iframe *frame);
+extern int i386_handle_breakpoint_exception(struct iframe *frame);
+
+#ifdef __cplusplus
+}
+#endif
+
 #endif	// _KERNEL_ARCH_X86_USER_DEBUGGER_H