Blackfin arch: add supporting for kgdb

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>

Documentation/blackfin/kgdb.txt

-			A Simple Guide to Configure KGDB
-
-			Sonic Zhang <sonic.zhang@analog.com>
-				Aug. 24th 2006
-
-
-This KGDB patch enables the kernel developer to do source level debugging on
-the kernel for the Blackfin architecture.  The debugging works over either the
-ethernet interface or one of the uarts.  Both software breakpoints and
-hardware breakpoints are supported in this version.
-http://docs.blackfin.uclinux.org/doku.php?id=kgdb
-
-
-2 known issues:
-1. This bug:
-       http://blackfin.uclinux.org/tracker/index.php?func=detail&aid=544&group_id=18&atid=145
-   The GDB client for Blackfin uClinux causes incorrect values of local
-   variables to be displayed when the user breaks the running of kernel in GDB.
-2. Because of a hardware bug in Blackfin 533 v1.0.3:
-       05000067 - Watchpoints (Hardware Breakpoints) are not supported
-   Hardware breakpoints cannot be set properly.
-
-
-Debug over Ethernet:
- 
-1. Compile and install the cross platform version of gdb for blackfin, which
-   can be found at $(BINROOT)/bfin-elf-gdb.
-
-2. Apply this patch to the 2.6.x kernel.  Select the menuconfig option under
-   "Kernel hacking" -> "Kernel debugging" -> "KGDB: kernel debug with remote gdb".
-   With this selected, option "Full Symbolic/Source Debugging support" and 
-   "Compile the kernel with frame pointers" are also selected.
-
-3. Select option "KGDB: connect over (Ethernet)".  Add "kgdboe=@target-IP/,@host-IP/" to
-   the option "Compiled-in Kernel Boot Parameter" under "Kernel hacking".
-
-4. Connect minicom to the serial port and boot the kernel image.
-
-5. Configure the IP "/> ifconfig eth0 target-IP"
-
-6. Start GDB client "bfin-elf-gdb vmlinux".
-
-7. Connect to the target "(gdb) target remote udp:target-IP:6443".
-
-8. Set software breakpoint "(gdb) break sys_open".
-
-9. Continue "(gdb) c".
-
-10. Run ls in the target console "/> ls".
-
-11. Breakpoint hits. "Breakpoint 1: sys_open(..."
-
-12. Display local variables and function paramters.
-    (*) This operation gives wrong results, see known issue 1.
-
-13. Single stepping "(gdb) si".
-
-14. Remove breakpoint 1. "(gdb) del 1"
-
-15. Set hardware breakpoint "(gdb) hbreak sys_open".
-
-16. Continue "(gdb) c".
-
-17. Run ls in the target console "/> ls".
-
-18. Hardware breakpoint hits. "Breakpoint 1: sys_open(...".
-    (*) This hardware breakpoint will not be hit, see known issue 2.
-
-19. Continue "(gdb) c".
-
-20. Interrupt the target in GDB "Ctrl+C".
-
-21. Detach from the target "(gdb) detach".
-
-22. Exit GDB "(gdb) quit".
-
-
-Debug over the UART:
-
-1. Compile and install the cross platform version of gdb for blackfin, which
-   can be found at $(BINROOT)/bfin-elf-gdb.
-
-2. Apply this patch to the 2.6.x kernel.  Select the menuconfig option under
-   "Kernel hacking" -> "Kernel debugging" -> "KGDB: kernel debug with remote gdb".
-   With this selected, option "Full Symbolic/Source Debugging support" and 
-   "Compile the kernel with frame pointers" are also selected.
-
-3. Select option "KGDB: connect over (UART)".  Set "KGDB: UART port number" to be
-   a different one from the console.  Don't forget to change the mode of
-   blackfin serial driver to PIO.  Otherwise kgdb works incorrectly on UART.
- 
-4. If you want connect to kgdb when the kernel boots, enable
-   "KGDB: Wait for gdb connection early" 
-
-5. Compile kernel.
-
-6. Connect minicom to the serial port of the console and boot the kernel image.
-
-7. Start GDB client "bfin-elf-gdb vmlinux".
-
-8. Set the baud rate in GDB "(gdb) set remotebaud 57600".
-
-9. Connect to the target on the second serial port "(gdb) target remote /dev/ttyS1".
-
-10. Set software breakpoint "(gdb) break sys_open".
-
-11. Continue "(gdb) c". 
-
-12. Run ls in the target console "/> ls". 
-
-13. A breakpoint is hit. "Breakpoint 1: sys_open(..."
-
-14. All other operations are the same as that in KGDB over Ethernet. 
-
-
-Debug over the same UART as console:
-
-1. Compile and install the cross platform version of gdb for blackfin, which
-   can be found at $(BINROOT)/bfin-elf-gdb.
-
-2. Apply this patch to the 2.6.x kernel.  Select the menuconfig option under
-   "Kernel hacking" -> "Kernel debugging" -> "KGDB: kernel debug with remote gdb".
-   With this selected, option "Full Symbolic/Source Debugging support" and 
-   "Compile the kernel with frame pointers" are also selected.
-
-3. Select option "KGDB: connect over UART".  Set "KGDB: UART port number" to console.
-   Don't forget to change the mode of blackfin serial driver to PIO.
-   Otherwise kgdb works incorrectly on UART.
- 
-4. If you want connect to kgdb when the kernel boots, enable
-   "KGDB: Wait for gdb connection early" 
-
-5. Connect minicom to the serial port and boot the kernel image. 
-
-6. (Optional) Ask target to wait for gdb connection by entering Ctrl+A. In minicom, you should enter Ctrl+A+A.
-
-7. Start GDB client "bfin-elf-gdb vmlinux".
-
-8. Set the baud rate in GDB "(gdb) set remotebaud 57600".
-
-9. Connect to the target "(gdb) target remote /dev/ttyS0".
-
-10. Set software breakpoint "(gdb) break sys_open".
-
-11. Continue "(gdb) c". Then enter Ctrl+C twice to stop GDB connection.
-
-12. Run ls in the target console "/> ls". Dummy string can be seen on the console.
-
-13. Then connect the gdb to target again. "(gdb) target remote /dev/ttyS0".
-    Now you will find a breakpoint is hit. "Breakpoint 1: sys_open(..."
-
-14. All other operations are the same as that in KGDB over Ethernet.  The only
-    difference is that after continue command in GDB, please stop GDB
-    connection by 2 "Ctrl+C"s and connect again after breakpoints are hit or
-    Ctrl+A is entered.

arch/blackfin/Kconfig.debug

@@ -2,6 +2,9 @@ menu "Kernel hacking"
 
 source "lib/Kconfig.debug"
 
+config HAVE_ARCH_KGDB
+       def_bool y
+
 config DEBUG_MMRS
 	bool "Generate Blackfin MMR tree"
 	select DEBUG_FS

arch/blackfin/include/asm/kgdb.h

@@ -124,9 +124,16 @@ enum regnames {
 /* Number of bytes of registers.  */
 #define NUMREGBYTES BFIN_NUM_REGS*4
 
-#define BREAKPOINT() asm("   EXCPT 2;");
-#define BREAK_INSTR_SIZE       2
-#define HW_BREAKPOINT_NUM		6
+static inline void arch_kgdb_breakpoint(void)
+{
+	asm("   EXCPT 2;");
+}
+#define BREAK_INSTR_SIZE	2
+#define CACHE_FLUSH_IS_SAFE	1
+#define HW_INST_WATCHPOINT_NUM	6
+#define HW_WATCHPOINT_NUM	8
+#define TYPE_INST_WATCHPOINT	0
+#define TYPE_DATA_WATCHPOINT	1
 
 /* Instruction watchpoint address control register bits mask */
 #define WPPWR		0x1
@@ -163,10 +170,11 @@ enum regnames {
 #define WPDAEN1		0x8
 #define WPDCNTEN0	0x10
 #define WPDCNTEN1	0x20
+
 #define WPDSRC0		0xc0
-#define WPDACC0		0x300
+#define WPDACC0_OFFSET	8
 #define WPDSRC1		0xc00
-#define WPDACC1		0x3000
+#define WPDACC1_OFFSET	12
 
 /* Watchpoint status register bits mask */
 #define STATIA0		0x1
@@ -178,7 +186,4 @@ enum regnames {
 #define STATDA0		0x40
 #define STATDA1		0x80
 
-extern void kgdb_print(const char *fmt, ...);
-extern void init_kgdb_uart(void);
-
 #endif

arch/blackfin/kernel/traps.c

@@ -43,12 +43,11 @@
 #include <asm/dma.h>
 
 #ifdef CONFIG_KGDB
-# include <linux/debugger.h>
 # include <linux/kgdb.h>
 
 # define CHK_DEBUGGER_TRAP() \
 	do { \
-		CHK_DEBUGGER(trapnr, sig, info.si_code, fp, ); \
+		kgdb_handle_exception(trapnr, sig, info.si_code, fp); \
 	} while (0)
 # define CHK_DEBUGGER_TRAP_MAYBE() \
 	do { \
@@ -300,7 +299,7 @@ asmlinkage void trap_c(struct pt_regs *fp)
 		info.si_code = SEGV_STACKFLOW;
 		sig = SIGSEGV;
 		printk(KERN_NOTICE EXC_0x03(KERN_NOTICE));
-		CHK_DEBUGGER_TRAP();
+		CHK_DEBUGGER_TRAP_MAYBE();
 		break;
 	/* 0x04 - User Defined, Caught by default */
 	/* 0x05 - User Defined, Caught by default */
@@ -329,7 +328,7 @@ asmlinkage void trap_c(struct pt_regs *fp)
 		info.si_code = TRAP_TRACEFLOW;
 		sig = SIGTRAP;
 		printk(KERN_NOTICE EXC_0x11(KERN_NOTICE));
-		CHK_DEBUGGER_TRAP();
+		CHK_DEBUGGER_TRAP_MAYBE();
 		break;
 	/* 0x12 - Reserved, Caught by default */
 	/* 0x13 - Reserved, Caught by default */
@@ -351,35 +350,35 @@ asmlinkage void trap_c(struct pt_regs *fp)
 		info.si_code = ILL_ILLOPC;
 		sig = SIGILL;
 		printk(KERN_NOTICE EXC_0x21(KERN_NOTICE));
-		CHK_DEBUGGER_TRAP();
+		CHK_DEBUGGER_TRAP_MAYBE();
 		break;
 	/* 0x22 - Illegal Instruction Combination, handled here */
 	case VEC_ILGAL_I:
 		info.si_code = ILL_ILLPARAOP;
 		sig = SIGILL;
 		printk(KERN_NOTICE EXC_0x22(KERN_NOTICE));
-		CHK_DEBUGGER_TRAP();
+		CHK_DEBUGGER_TRAP_MAYBE();
 		break;
 	/* 0x23 - Data CPLB protection violation, handled here */
 	case VEC_CPLB_VL:
 		info.si_code = ILL_CPLB_VI;
 		sig = SIGBUS;
 		printk(KERN_NOTICE EXC_0x23(KERN_NOTICE));
-		CHK_DEBUGGER_TRAP();
+		CHK_DEBUGGER_TRAP_MAYBE();
 		break;
 	/* 0x24 - Data access misaligned, handled here */
 	case VEC_MISALI_D:
 		info.si_code = BUS_ADRALN;
 		sig = SIGBUS;
 		printk(KERN_NOTICE EXC_0x24(KERN_NOTICE));
-		CHK_DEBUGGER_TRAP();
+		CHK_DEBUGGER_TRAP_MAYBE();
 		break;
 	/* 0x25 - Unrecoverable Event, handled here */
 	case VEC_UNCOV:
 		info.si_code = ILL_ILLEXCPT;
 		sig = SIGILL;
 		printk(KERN_NOTICE EXC_0x25(KERN_NOTICE));
-		CHK_DEBUGGER_TRAP();
+		CHK_DEBUGGER_TRAP_MAYBE();
 		break;
 	/* 0x26 - Data CPLB Miss, normal case is handled in _cplb_hdr,
 		error case is handled here */
@@ -387,7 +386,6 @@ asmlinkage void trap_c(struct pt_regs *fp)
 		info.si_code = BUS_ADRALN;
 		sig = SIGBUS;
 		printk(KERN_NOTICE EXC_0x26(KERN_NOTICE));
-		CHK_DEBUGGER_TRAP();
 		break;
 	/* 0x27 - Data CPLB Multiple Hits - Linux Trap Zero, handled here */
 	case VEC_CPLB_MHIT:
@@ -399,7 +397,7 @@ asmlinkage void trap_c(struct pt_regs *fp)
 		else
 #endif
 			printk(KERN_NOTICE EXC_0x27(KERN_NOTICE));
-		CHK_DEBUGGER_TRAP();
+		CHK_DEBUGGER_TRAP_MAYBE();
 		break;
 	/* 0x28 - Emulation Watchpoint, handled here */
 	case VEC_WATCH:
@@ -418,7 +416,7 @@ asmlinkage void trap_c(struct pt_regs *fp)
 		info.si_code = BUS_OPFETCH;
 		sig = SIGBUS;
 		printk(KERN_NOTICE "BF535: VEC_ISTRU_VL\n");
-		CHK_DEBUGGER_TRAP();
+		CHK_DEBUGGER_TRAP_MAYBE();
 		break;
 #else
 	/* 0x29 - Reserved, Caught by default */
@@ -428,21 +426,20 @@ asmlinkage void trap_c(struct pt_regs *fp)
 		info.si_code = BUS_ADRALN;
 		sig = SIGBUS;
 		printk(KERN_NOTICE EXC_0x2A(KERN_NOTICE));
-		CHK_DEBUGGER_TRAP();
+		CHK_DEBUGGER_TRAP_MAYBE();
 		break;
 	/* 0x2B - Instruction CPLB protection violation, handled here */
 	case VEC_CPLB_I_VL:
 		info.si_code = ILL_CPLB_VI;
 		sig = SIGBUS;
 		printk(KERN_NOTICE EXC_0x2B(KERN_NOTICE));
-		CHK_DEBUGGER_TRAP();
+		CHK_DEBUGGER_TRAP_MAYBE();
 		break;
 	/* 0x2C - Instruction CPLB miss, handled in _cplb_hdr */
 	case VEC_CPLB_I_M:
 		info.si_code = ILL_CPLB_MISS;
 		sig = SIGBUS;
 		printk(KERN_NOTICE EXC_0x2C(KERN_NOTICE));
-		CHK_DEBUGGER_TRAP();
 		break;
 	/* 0x2D - Instruction CPLB Multiple Hits, handled here */
 	case VEC_CPLB_I_MHIT:
@@ -454,14 +451,14 @@ asmlinkage void trap_c(struct pt_regs *fp)
 		else
 #endif
 			printk(KERN_NOTICE EXC_0x2D(KERN_NOTICE));
-		CHK_DEBUGGER_TRAP();
+		CHK_DEBUGGER_TRAP_MAYBE();
 		break;
 	/* 0x2E - Illegal use of Supervisor Resource, handled here */
 	case VEC_ILL_RES:
 		info.si_code = ILL_PRVOPC;
 		sig = SIGILL;
 		printk(KERN_NOTICE EXC_0x2E(KERN_NOTICE));
-		CHK_DEBUGGER_TRAP();
+		CHK_DEBUGGER_TRAP_MAYBE();
 		break;
 	/* 0x2F - Reserved, Caught by default */
 	/* 0x30 - Reserved, Caught by default */
@@ -508,14 +505,14 @@ asmlinkage void trap_c(struct pt_regs *fp)
 			printk(KERN_NOTICE HWC_default(KERN_NOTICE));
 			break;
 		}
-		CHK_DEBUGGER_TRAP();
+		CHK_DEBUGGER_TRAP_MAYBE();
 		break;
 	default:
 		info.si_code = TRAP_ILLTRAP;
 		sig = SIGTRAP;
 		printk(KERN_EMERG "Caught Unhandled Exception, code = %08lx\n",
 			(fp->seqstat & SEQSTAT_EXCAUSE));
-		CHK_DEBUGGER_TRAP();
+		CHK_DEBUGGER_TRAP_MAYBE();
 		break;
 	}
 

arch/blackfin/mach-bf561/include/mach/mem_map.h

@@ -35,9 +35,16 @@
 /* Memory Map for ADSP-BF561 processors */
 
 #ifdef CONFIG_BF561
-#define L1_CODE_START     0xFFA00000
-#define L1_DATA_A_START     0xFF800000
-#define L1_DATA_B_START     0xFF900000
+#define COREA_L1_CODE_START     0xFFA00000
+#define COREA_L1_DATA_A_START     0xFF800000
+#define COREA_L1_DATA_B_START     0xFF900000
+#define COREB_L1_CODE_START     0xFF600000
+#define COREB_L1_DATA_A_START     0xFF500000
+#define COREB_L1_DATA_B_START     0xFF400000
+
+#define L1_CODE_START     COREA_L1_CODE_START
+#define L1_DATA_A_START     COREA_L1_DATA_A_START
+#define L1_DATA_B_START     COREA_L1_DATA_B_START
 
 #define L1_CODE_LENGTH      0x4000
 
@@ -72,7 +79,10 @@
 
 /* Scratch Pad Memory */
 
-#define L1_SCRATCH_START	0xFFB00000
+#define COREA_L1_SCRATCH_START	0xFFB00000
+#define COREB_L1_SCRATCH_START	0xFF700000
+
+#define L1_SCRATCH_START	COREA_L1_SCRATCH_START
 #define L1_SCRATCH_LENGTH	0x1000
 
 #endif				/* _MEM_MAP_533_H_ */

arch/blackfin/mach-common/entry.S

@@ -190,8 +190,8 @@ ENTRY(_ex_single_step)
 	if cc jump .Lfind_priority_done;
 	jump.s .Lfind_priority_start;
 .Lfind_priority_done:
-	p4.l = _debugger_step;
-	p4.h = _debugger_step;
+	p4.l = _kgdb_single_step;
+	p4.h = _kgdb_single_step;
 	r6 = [p4];
 	cc = r6 == 0;
 	if cc jump .Ldo_single_step;
@@ -1071,7 +1071,12 @@ ENTRY(_ex_table)
 	 */
 	.long _ex_syscall       /* 0x00 - User Defined - Linux Syscall */
 	.long _ex_soft_bp       /* 0x01 - User Defined - Software breakpoint */
+#ifdef	CONFIG_KGDB
+	.long _ex_trap_c	/* 0x02 - User Defined - KGDB initial connection
+							 and break signal trap */
+#else
 	.long _ex_replaceable   /* 0x02 - User Defined */
+#endif
 	.long _ex_trap_c        /* 0x03 - User Defined - userspace stack overflow */
 	.long _ex_trap_c        /* 0x04 - User Defined - dump trace buffer */
 	.long _ex_replaceable   /* 0x05 - User Defined */

arch/blackfin/mach-common/ints-priority.c

@@ -1136,8 +1136,4 @@ void do_irq(int vec, struct pt_regs *fp)
 		vec = ivg->irqno;
 	}
 	asm_do_IRQ(vec, fp);
-
-#ifdef CONFIG_KGDB
-	kgdb_process_breakpoint();
-#endif
 }