diff options
| -rw-r--r-- | arch/blackfin/Kconfig | 81 | ||||
| -rw-r--r-- | arch/blackfin/kernel/irqchip.c | 9 | ||||
| -rw-r--r-- | arch/blackfin/kernel/traps.c | 53 | ||||
| -rw-r--r-- | arch/blackfin/mach-bf533/head.S | 2 | ||||
| -rw-r--r-- | arch/blackfin/mach-bf537/head.S | 2 | ||||
| -rw-r--r-- | arch/blackfin/mach-bf548/head.S | 2 | ||||
| -rw-r--r-- | arch/blackfin/mach-bf561/head.S | 2 | ||||
| -rw-r--r-- | arch/blackfin/mach-common/entry.S | 73 | ||||
| -rw-r--r-- | include/asm-blackfin/trace.h | 55 |
9 files changed, 259 insertions, 20 deletions
diff --git a/arch/blackfin/Kconfig b/arch/blackfin/Kconfig index 9ce675e..a7a6e0c5 100644 --- a/arch/blackfin/Kconfig +++ b/arch/blackfin/Kconfig @@ -1024,8 +1024,89 @@ config DEBUG_HUNT_FOR_ZERO Enabling this option will take up an extra entry in CPLB table. Otherwise, there is no extra overhead. +config DEBUG_BFIN_HWTRACE_ON + bool "Turn on Blackfin's Hardware Trace" + default y + help + All Blackfins include a Trace Unit which stores a history of the last + 16 changes in program flow taken by the program sequencer. The history + allows the user to recreate the program sequencer’s recent path. This + can be handy when an application dies - we print out the execution + path of how it got to the offending instruction. + + By turning this off, you may save a tiny amount of power. + +choice + prompt "Omit loop Tracing" + default DEBUG_BFIN_HWTRACE_COMPRESSION_OFF + depends on DEBUG_BFIN_HWTRACE_ON + help + The trace buffer can be configured to omit recording of changes in + program flow that match either the last entry or one of the last + two entries. Omitting one of these entries from the record prevents + the trace buffer from overflowing because of any sort of loop (for, do + while, etc) in the program. + + Because zero-overhead Hardware loops are not recorded in the trace buffer, + this feature can be used to prevent trace overflow from loops that + are nested four deep. + +config DEBUG_BFIN_HWTRACE_COMPRESSION_OFF + bool "Trace all Loops" + help + The trace buffer records all changes of flow + +config DEBUG_BFIN_HWTRACE_COMPRESSION_ONE + bool "Compress single-level loops" + help + The trace buffer does not record single loops - helpful if trace + is spinning on a while or do loop. + +config DEBUG_BFIN_HWTRACE_COMPRESSION_TWO + bool "Compress two-level loops" + help + The trace buffer does not record loops two levels deep. Helpful if + the trace is spinning in a nested loop + +endchoice + +config DEBUG_BFIN_HWTRACE_COMPRESSION + int + depends on DEBUG_BFIN_HWTRACE_ON + default 0 if DEBUG_BFIN_HWTRACE_COMPRESSION_OFF + default 1 if DEBUG_BFIN_HWTRACE_COMPRESSION_ONE + default 2 if DEBUG_BFIN_HWTRACE_COMPRESSION_TWO + + +config DEBUG_BFIN_HWTRACE_EXPAND + bool "Expand Trace Buffer greater than 16 entries" + depends on DEBUG_BFIN_HWTRACE_ON + default n + help + By selecting this option, every time the 16 hardware entries in + the Blackfin's HW Trace buffer are full, the kernel will move them + into a software buffer, for dumping when there is an issue. This + has a great impact on performance, (an interrupt every 16 change of + flows) and should normally be turned off, except in those nasty + debugging sessions + +config DEBUG_BFIN_HWTRACE_EXPAND_LEN + int "Size of Trace buffer (in power of 2k)" + range 0 4 + depends on DEBUG_BFIN_HWTRACE_EXPAND + default 1 + help + This sets the size of the software buffer that the trace information + is kept in. + 0 for (2^0) 1k, or 256 entries, + 1 for (2^1) 2k, or 512 entries, + 2 for (2^2) 4k, or 1024 entries, + 3 for (2^3) 8k, or 2048 entries, + 4 for (2^4) 16k, or 4096 entries + config DEBUG_BFIN_NO_KERN_HWTRACE bool "Trace user apps (turn off hwtrace in kernel)" + depends on DEBUG_BFIN_HWTRACE_ON default n help Some pieces of the kernel contain a lot of flow changes which can diff --git a/arch/blackfin/kernel/irqchip.c b/arch/blackfin/kernel/irqchip.c index 1fc001c7..462ae41 100644 --- a/arch/blackfin/kernel/irqchip.c +++ b/arch/blackfin/kernel/irqchip.c @@ -34,6 +34,7 @@ #include <linux/kallsyms.h> #include <linux/interrupt.h> #include <linux/irq.h> +#include <asm/trace.h> static unsigned long irq_err_count; static spinlock_t irq_controller_lock; @@ -144,4 +145,12 @@ void __init init_IRQ(void) } init_arch_irq(); + +#ifdef CONFIG_DEBUG_BFIN_HWTRACE_EXPAND + /* Now that evt_ivhw is set up, turn this on */ + trace_buff_offset = 0; + bfin_write_TBUFCTL(BFIN_TRACE_ON); + printk(KERN_INFO "Hardware Trace expanded to %ik\n", + 1 << CONFIG_DEBUG_BFIN_HWTRACE_EXPAND_LEN); +#endif } diff --git a/arch/blackfin/kernel/traps.c b/arch/blackfin/kernel/traps.c index 792a841..0ec02fe6 100644 --- a/arch/blackfin/kernel/traps.c +++ b/arch/blackfin/kernel/traps.c @@ -55,6 +55,7 @@ asmlinkage void trap_c(struct pt_regs *fp); int kstack_depth_to_print = 48; +#ifdef CONFIG_DEBUG_BFIN_HWTRACE_ON static int printk_address(unsigned long address) { struct vm_list_struct *vml; @@ -131,10 +132,14 @@ static int printk_address(unsigned long address) /* we were unable to find this address anywhere */ return printk("[<0x%p>]", (void *)address); } +#endif asmlinkage void trap_c(struct pt_regs *fp) { - int j, sig = 0; +#ifdef CONFIG_DEBUG_BFIN_HWTRACE_ON + int j; +#endif + int sig = 0; siginfo_t info; unsigned long trapnr = fp->seqstat & SEQSTAT_EXCAUSE; @@ -429,24 +434,56 @@ asmlinkage void trap_c(struct pt_regs *fp) /* Typical exception handling routines */ +#define EXPAND_LEN ((1 << CONFIG_DEBUG_BFIN_HWTRACE_EXPAND_LEN) * 256 - 1) + void dump_bfin_trace_buffer(void) { - int tflags; +#ifdef CONFIG_DEBUG_BFIN_HWTRACE_ON + int tflags, i = 0; +#ifdef CONFIG_DEBUG_BFIN_HWTRACE_EXPAND + int j, index; +#endif + trace_buffer_save(tflags); + printk(KERN_EMERG "Hardware Trace:\n"); + if (likely(bfin_read_TBUFSTAT() & TBUFCNT)) { - int i; - printk(KERN_EMERG "Hardware Trace:\n"); - for (i = 0; bfin_read_TBUFSTAT() & TBUFCNT; i++) { - printk(KERN_EMERG "%2i Target : ", i); + for (; bfin_read_TBUFSTAT() & TBUFCNT; i++) { + printk(KERN_EMERG "%4i Target : ", i); printk_address((unsigned long)bfin_read_TBUF()); - printk("\n" KERN_EMERG " Source : "); + printk("\n" KERN_EMERG " Source : "); printk_address((unsigned long)bfin_read_TBUF()); printk("\n"); } } +#ifdef CONFIG_DEBUG_BFIN_HWTRACE_EXPAND + if (trace_buff_offset) + index = trace_buff_offset/4 - 1; + else + index = EXPAND_LEN; + + j = (1 << CONFIG_DEBUG_BFIN_HWTRACE_EXPAND_LEN) * 128; + while (j) { + printk(KERN_EMERG "%4i Target : ", i); + printk_address(software_trace_buff[index]); + index -= 1; + if (index < 0 ) + index = EXPAND_LEN; + printk("\n" KERN_EMERG " Source : "); + printk_address(software_trace_buff[index]); + index -= 1; + if (index < 0) + index = EXPAND_LEN; + printk("\n"); + j--; + i++; + } +#endif + trace_buffer_restore(tflags); +#endif } EXPORT_SYMBOL(dump_bfin_trace_buffer); @@ -510,7 +547,9 @@ void show_stack(struct task_struct *task, unsigned long *stack) void dump_stack(void) { unsigned long stack; +#ifdef CONFIG_DEBUG_BFIN_HWTRACE_ON int tflags; +#endif trace_buffer_save(tflags); dump_bfin_trace_buffer(); show_stack(current, &stack); diff --git a/arch/blackfin/mach-bf533/head.S b/arch/blackfin/mach-bf533/head.S index 9c5378b..1d5b9db 100644 --- a/arch/blackfin/mach-bf533/head.S +++ b/arch/blackfin/mach-bf533/head.S @@ -98,7 +98,7 @@ ENTRY(__start) M2 = r0; M3 = r0; - trace_buffer_start(p0,r0); + trace_buffer_init(p0,r0); P0 = R1; R0 = R1; diff --git a/arch/blackfin/mach-bf537/head.S b/arch/blackfin/mach-bf537/head.S index 82ea047..6dbcb77 100644 --- a/arch/blackfin/mach-bf537/head.S +++ b/arch/blackfin/mach-bf537/head.S @@ -96,7 +96,7 @@ ENTRY(__start) M2 = r0; M3 = r0; - trace_buffer_start(p0,r0); + trace_buffer_init(p0,r0); P0 = R1; R0 = R1; diff --git a/arch/blackfin/mach-bf548/head.S b/arch/blackfin/mach-bf548/head.S index 72087c2..e53d74d 100644 --- a/arch/blackfin/mach-bf548/head.S +++ b/arch/blackfin/mach-bf548/head.S @@ -93,7 +93,7 @@ ENTRY(__stext) M2 = r0; M3 = r0; - trace_buffer_start(p0,r0); + trace_buffer_init(p0,r0); P0 = R1; R0 = R1; diff --git a/arch/blackfin/mach-bf561/head.S b/arch/blackfin/mach-bf561/head.S index 83cd3f9..8c9f73b 100644 --- a/arch/blackfin/mach-bf561/head.S +++ b/arch/blackfin/mach-bf561/head.S @@ -96,7 +96,7 @@ ENTRY(__start) M2 = r0; M3 = r0; - trace_buffer_start(p0,r0); + trace_buffer_init(p0,r0); P0 = R1; R0 = R1; diff --git a/arch/blackfin/mach-common/entry.S b/arch/blackfin/mach-common/entry.S index 207e697..ab278a7 100644 --- a/arch/blackfin/mach-common/entry.S +++ b/arch/blackfin/mach-common/entry.S @@ -731,6 +731,75 @@ ENTRY(_init_exception_buff) rts; ENDPROC(_init_exception_buff) +/* We handle this 100% in exception space - to reduce overhead + * Only potiential problem is if the software buffer gets swapped out of the + * CPLB table - then double fault. - so we don't let this happen in other places + */ +#ifdef CONFIG_DEBUG_BFIN_HWTRACE_EXPAND +ENTRY(_ex_trace_buff_full) + [--sp] = P3; + [--sp] = P2; + [--sp] = LC0; + [--sp] = LT0; + [--sp] = LB0; + P5.L = _trace_buff_offset; + P5.H = _trace_buff_offset; + P3 = [P5]; /* trace_buff_offset */ + P5.L = lo(TBUFSTAT); + P5.H = hi(TBUFSTAT); + R7 = [P5]; + R7 <<= 1; /* double, since we need to read twice */ + LC0 = R7; + R7 <<= 2; /* need to shift over again, + * to get the number of bytes */ + P5.L = lo(TBUF); + P5.H = hi(TBUF); + R6 = ((1 << CONFIG_DEBUG_BFIN_HWTRACE_EXPAND_LEN)*1024) - 1; + + P2 = R7; + P3 = P3 + P2; + R7 = P3; + R7 = R7 & R6; + P3 = R7; + P2.L = _trace_buff_offset; + P2.H = _trace_buff_offset; + [P2] = P3; + + P2.L = _software_trace_buff; + P2.H = _software_trace_buff; + + LSETUP (.Lstart, .Lend) LC0; +.Lstart: + R7 = [P5]; /* read TBUF */ + P4 = P3 + P2; + [P4] = R7; + P3 += -4; + R7 = P3; + R7 = R7 & R6; +.Lend: + P3 = R7; + + LB0 = [sp++]; + LT0 = [sp++]; + LC0 = [sp++]; + P2 = [sp++]; + P3 = [sp++]; + jump _return_from_exception; + +#if CONFIG_DEBUG_BFIN_HWTRACE_EXPAND_LEN == 4 +.data +#else +.section .l1.data.B +#endif +ENTRY(_trace_buff_offset) + .long 0; +ALIGN +ENTRY(_software_trace_buff) + .rept ((1 << CONFIG_DEBUG_BFIN_HWTRACE_EXPAND_LEN)*256); + .long 0 + .endr +#endif + /* * Put these in the kernel data section - that should always be covered by * a CPLB. This is needed to ensure we don't get double fault conditions @@ -764,7 +833,11 @@ _extable: .long _ex_trap_c /* 0x0E - User Defined */ .long _ex_trap_c /* 0x0F - User Defined */ .long _ex_single_step /* 0x10 - HW Single step */ +#ifdef CONFIG_DEBUG_BFIN_HWTRACE_EXPAND + .long _ex_trace_buff_full /* 0x11 - Trace Buffer Full */ +#else .long _ex_trap_c /* 0x11 - Trace Buffer Full */ +#endif .long _ex_trap_c /* 0x12 - Reserved */ .long _ex_trap_c /* 0x13 - Reserved */ .long _ex_trap_c /* 0x14 - Reserved */ diff --git a/include/asm-blackfin/trace.h b/include/asm-blackfin/trace.h index 9c2474c..6313aac 100644 --- a/include/asm-blackfin/trace.h +++ b/include/asm-blackfin/trace.h @@ -6,23 +6,46 @@ #ifndef _BLACKFIN_TRACE_ #define _BLACKFIN_TRACE_ +/* Normally, we use ON, but you can't turn on software expansion until + * interrupts subsystem is ready + */ + +#define BFIN_TRACE_INIT ((CONFIG_DEBUG_BFIN_HWTRACE_COMPRESSION << 4) | 0x03) +#ifdef CONFIG_DEBUG_BFIN_HWTRACE_EXPAND +#define BFIN_TRACE_ON (BFIN_TRACE_INIT | (CONFIG_DEBUG_BFIN_HWTRACE_EXPAND << 2)) +#else +#define BFIN_TRACE_ON (BFIN_TRACE_INIT) +#endif + #ifndef __ASSEMBLY__ +extern unsigned long trace_buff_offset; +extern unsigned long software_trace_buff[]; + /* Trace Macros for C files */ +#ifdef CONFIG_DEBUG_BFIN_HWTRACE_ON + #define trace_buffer_save(x) \ - do { \ - (x) = bfin_read_TBUFCTL(); \ - bfin_write_TBUFCTL((x) & ~TBUFEN); \ - } while (0) + do { \ + (x) = bfin_read_TBUFCTL(); \ + bfin_write_TBUFCTL((x) & ~TBUFEN); \ + } while (0) #define trace_buffer_restore(x) \ - do { \ - bfin_write_TBUFCTL((x)); \ - } while (0) + do { \ + bfin_write_TBUFCTL((x)); \ + } while (0) +#else /* DEBUG_BFIN_HWTRACE_ON */ + +#define trace_buffer_save(x) +#define trace_buffer_restore(x) +#endif /* CONFIG_DEBUG_BFIN_HWTRACE_ON */ #else /* Trace Macros for Assembly files */ +#ifdef CONFIG_DEBUG_BFIN_HWTRACE_ON + #define TRACE_BUFFER_START(preg, dreg) trace_buffer_start(preg, dreg) #define TRACE_BUFFER_STOP(preg, dreg) trace_buffer_stop(preg, dreg) @@ -32,12 +55,26 @@ dreg = 0x1; \ [preg] = dreg; -#define trace_buffer_start(preg, dreg) \ +#define trace_buffer_start(preg, dreg) \ preg.L = LO(TBUFCTL); \ preg.H = HI(TBUFCTL); \ - dreg = 0x13; \ + dreg = BFIN_TRACE_ON; \ + [preg] = dreg; + +#define trace_buffer_init(preg, dreg) \ + preg.L = LO(TBUFCTL); \ + preg.H = HI(TBUFCTL); \ + dreg = BFIN_TRACE_INIT; \ [preg] = dreg; +#else /* CONFIG_DEBUG_BFIN_HWTRACE_ON */ + +#define trace_buffer_stop(preg, dreg) +#define trace_buffer_start(preg, dreg) +#define trace_buffer_init(preg, dreg) + +#endif /* CONFIG_DEBUG_BFIN_HWTRACE_ON */ + #ifdef CONFIG_DEBUG_BFIN_NO_KERN_HWTRACE # define DEBUG_START_HWTRACE(preg, dreg) trace_buffer_start(preg, dreg) # define DEBUG_STOP_HWTRACE(preg, dreg) trace_buffer_stop(preg, dreg) |
