From: Mike Dunn Date: Thu, 2 Dec 2010 19:08:28 +0000 (-0800) Subject: xscale: trace buffer remains enabled until explicitly disabled X-Git-Tag: v0.5.0-rc1~294 X-Git-Url: https://git.sur5r.net/?a=commitdiff_plain;h=2e7d51c96a80f7fb2135af8558886e6516ddf661;p=openocd xscale: trace buffer remains enabled until explicitly disabled Hi everyone, Since a call went out for patches... been sitting on this for months. For some reason, the xscale trace buffer is automatically disabled as soon as a break occurs and the trace data is collected. This patch was a result of the frustration of always re-enabling it, or else hitting a breakpoint and checking the trace data, only to discover that I forgot to re-enable it before resuming. Don't see why it should work this way. There is no run-time penalty, AFAIK. Along the way, I also cleaned up a little by removing the ugly practice of recording wrap mode by setting the fill count variable to "-1", replacing it with an enum that records the trace mode. I've been using this for months. Comments, criticisms gratefully received. Mike Signed-off-by: Mike Dunn --- diff --git a/src/target/xscale.c b/src/target/xscale.c index e0ce400b..32c656bb 100644 --- a/src/target/xscale.c +++ b/src/target/xscale.c @@ -1044,21 +1044,20 @@ static int xscale_debug_entry(struct target *target) xscale->armv4_5_mmu.armv4_5_cache.i_cache_enabled = (xscale->cp15_control_reg & 0x1000U) ? 1 : 0; /* tracing enabled, read collected trace data */ - if (xscale->trace.buffer_enabled) + if (xscale->trace.mode != XSCALE_TRACE_DISABLED) { xscale_read_trace(target); - xscale->trace.buffer_fill--; - /* resume if we're still collecting trace data */ - if ((xscale->arch_debug_reason == XSCALE_DBG_REASON_TB_FULL) - && (xscale->trace.buffer_fill > 0)) + /* Resume if entered debug due to buffer fill and we're still collecting + * trace data. Note that a debug exception due to trace buffer full + * can only happen in fill mode. */ + if (xscale->arch_debug_reason == XSCALE_DBG_REASON_TB_FULL) { + if (--xscale->trace.fill_counter > 0) xscale_resume(target, 1, 0x0, 1, 0); } - else - { - xscale->trace.buffer_enabled = 0; - } + else /* entered debug for other reason; reset counter */ + xscale->trace.fill_counter = 0; } return ERROR_OK; @@ -1162,6 +1161,20 @@ static void xscale_enable_breakpoints(struct target *target) } } +static void xscale_free_trace_data(struct xscale_common *xscale) +{ + struct xscale_trace_data *td = xscale->trace.data; + while (td) + { + struct xscale_trace_data *next_td = td->next; + if (td->entries) + free(td->entries); + free(td); + td = next_td; + } + xscale->trace.data = NULL; +} + static int xscale_resume(struct target *target, int current, uint32_t address, int handle_breakpoints, int debug_execution) { @@ -1210,7 +1223,7 @@ static int xscale_resume(struct target *target, int current, if (breakpoint != NULL) { uint32_t next_pc; - int saved_trace_buffer_enabled; + enum trace_mode saved_trace_mode; /* there's a breakpoint at the current PC, we have to step over it */ LOG_DEBUG("unset breakpoint at 0x%8.8" PRIx32 "", breakpoint->address); @@ -1253,14 +1266,14 @@ static int xscale_resume(struct target *target, int current, buf_get_u32(armv4_5->pc->value, 0, 32)); /* disable trace data collection in xscale_debug_entry() */ - saved_trace_buffer_enabled = xscale->trace.buffer_enabled; - xscale->trace.buffer_enabled = 0; + saved_trace_mode = xscale->trace.mode; + xscale->trace.mode = XSCALE_TRACE_DISABLED; /* wait for and process debug entry */ xscale_debug_entry(target); /* re-enable trace buffer, if enabled previously */ - xscale->trace.buffer_enabled = saved_trace_buffer_enabled; + xscale->trace.mode = saved_trace_mode; LOG_DEBUG("disable single-step"); xscale_disable_single_step(target); @@ -1279,8 +1292,21 @@ static int xscale_resume(struct target *target, int current, /* send resume request (command 0x30 or 0x31) * clean the trace buffer if it is to be enabled (0x62) */ - if (xscale->trace.buffer_enabled) + if (xscale->trace.mode != XSCALE_TRACE_DISABLED) { + if (xscale->trace.mode == XSCALE_TRACE_FILL) + { + /* If trace enabled in fill mode and starting collection of new set + * of buffers, initialize buffer counter and free previous buffers */ + if (xscale->trace.fill_counter == 0) + { + xscale->trace.fill_counter = xscale->trace.buffer_fill; + xscale_free_trace_data(xscale); + } + } + else /* wrap mode; free previous buffer */ + xscale_free_trace_data(xscale); + xscale_send_u32(target, 0x62); xscale_send_u32(target, 0x31); } @@ -1356,7 +1382,7 @@ static int xscale_step_inner(struct target *target, int current, /* send resume request (command 0x30 or 0x31) * clean the trace buffer if it is to be enabled (0x62) */ - if (xscale->trace.buffer_enabled) + if (xscale->trace.mode != XSCALE_TRACE_DISABLED) { if ((retval = xscale_send_u32(target, 0x62)) != ERROR_OK) return retval; @@ -1533,6 +1559,9 @@ static int xscale_deassert_reset(struct target *target) breakpoint = breakpoint->next; } + xscale->trace.mode = XSCALE_TRACE_DISABLED; + xscale_free_trace_data(xscale); + register_cache_invalidate(xscale->armv4_5_common.core_cache); /* FIXME mark hardware watchpoints got unset too. Also, @@ -3120,11 +3149,11 @@ static int xscale_init_arch_info(struct target *target, xscale->vector_catch = 0x1; - xscale->trace.capture_status = TRACE_IDLE; xscale->trace.data = NULL; xscale->trace.image = NULL; - xscale->trace.buffer_enabled = 0; + xscale->trace.mode = XSCALE_TRACE_DISABLED; xscale->trace.buffer_fill = 0; + xscale->trace.fill_counter = 0; /* prepare ARMv4/5 specific information */ armv4_5->arch_info = xscale; @@ -3466,47 +3495,54 @@ COMMAND_HANDLER(xscale_handle_trace_buffer_command) return ERROR_OK; } - if ((CMD_ARGC >= 1) && (strcmp("enable", CMD_ARGV[0]) == 0)) - { - struct xscale_trace_data *td, *next_td; - xscale->trace.buffer_enabled = 1; - - /* free old trace data */ - td = xscale->trace.data; - while (td) - { - next_td = td->next; - - if (td->entries) - free(td->entries); - free(td); - td = next_td; - } - xscale->trace.data = NULL; - } - else if ((CMD_ARGC >= 1) && (strcmp("disable", CMD_ARGV[0]) == 0)) + if (CMD_ARGC >= 1) { - xscale->trace.buffer_enabled = 0; + if (strcmp("enable", CMD_ARGV[0]) == 0) + xscale->trace.mode = XSCALE_TRACE_WRAP; /* default */ + else if (strcmp("disable", CMD_ARGV[0]) == 0) + xscale->trace.mode = XSCALE_TRACE_DISABLED; + else + return ERROR_INVALID_ARGUMENTS; } - if ((CMD_ARGC >= 2) && (strcmp("fill", CMD_ARGV[1]) == 0)) + if (CMD_ARGC >= 2 && xscale->trace.mode != XSCALE_TRACE_DISABLED) { - uint32_t fill = 1; - if (CMD_ARGC >= 3) - COMMAND_PARSE_NUMBER(u32, CMD_ARGV[2], fill); - xscale->trace.buffer_fill = fill; + if (strcmp("fill", CMD_ARGV[1]) == 0) + { + int buffcount = 1; /* default */ + if (CMD_ARGC >= 3) + COMMAND_PARSE_NUMBER(int, CMD_ARGV[2], buffcount); + if (buffcount < 1) /* invalid */ + { + command_print(CMD_CTX, "fill buffer count must be > 0"); + xscale->trace.mode = XSCALE_TRACE_DISABLED; + return ERROR_INVALID_ARGUMENTS; + } + xscale->trace.buffer_fill = buffcount; + xscale->trace.mode = XSCALE_TRACE_FILL; + } + else if (strcmp("wrap", CMD_ARGV[1]) == 0) + xscale->trace.mode = XSCALE_TRACE_WRAP; + else + { + xscale->trace.mode = XSCALE_TRACE_DISABLED; + return ERROR_INVALID_ARGUMENTS; + } } - else if ((CMD_ARGC >= 2) && (strcmp("wrap", CMD_ARGV[1]) == 0)) + + if (xscale->trace.mode != XSCALE_TRACE_DISABLED) { - xscale->trace.buffer_fill = -1; + char fill_string[12]; + sprintf(fill_string, "fill %" PRId32, xscale->trace.buffer_fill); + command_print(CMD_CTX, "trace buffer enabled (%s)", + (xscale->trace.mode == XSCALE_TRACE_FILL) + ? fill_string : "wrap"); } - - command_print(CMD_CTX, "trace buffer %s (%s)", - (xscale->trace.buffer_enabled) ? "enabled" : "disabled", - (xscale->trace.buffer_fill > 0) ? "fill" : "wrap"); - + else + command_print(CMD_CTX, "trace buffer disabled"); + dcsr_value = buf_get_u32(xscale->reg_cache->reg_list[XSCALE_DCSR].value, 0, 32); - if (xscale->trace.buffer_fill >= 0) + if (xscale->trace.mode == XSCALE_TRACE_FILL) xscale_write_dcsr_sw(target, (dcsr_value & 0xfffffffc) | 2); else xscale_write_dcsr_sw(target, dcsr_value & 0xfffffffc); @@ -3774,7 +3810,7 @@ static const struct command_registration xscale_exec_command_handlers[] = { .mode = COMMAND_EXEC, .help = "display trace buffer status, enable or disable " "tracing, and optionally reconfigure trace mode", - .usage = "['enable'|'disable' ['fill' number|'wrap']]", + .usage = "['enable'|'disable' ['fill' [number]|'wrap']]", }, { .name = "dump_trace", diff --git a/src/target/xscale.h b/src/target/xscale.h index d429336e..e480da93 100644 --- a/src/target/xscale.h +++ b/src/target/xscale.h @@ -71,13 +71,20 @@ struct xscale_trace_data struct xscale_trace_data *next; }; +enum trace_mode +{ + XSCALE_TRACE_DISABLED, + XSCALE_TRACE_FILL, + XSCALE_TRACE_WRAP +}; + struct xscale_trace { - trace_status_t capture_status; /* current state of capture run */ struct image *image; /* source for target opcodes */ struct xscale_trace_data *data; /* linked list of collected trace data */ - int buffer_enabled; /* whether trace buffer is enabled */ - int buffer_fill; /* maximum number of trace runs to read (-1 for wrap-around) */ + int buffer_fill; /* maximum number of trace runs to read */ + int fill_counter; /* running count during trace collection */ + enum trace_mode mode; enum arm_state core_state; /* current core state (ARM, Thumb) */ };