* Copyright (C) 2005 by Dominic Rath *
* Dominic.Rath@gmx.de *
* *
+ * Copyright (C) 2007,2008 Øyvind Harboe *
+ * oyvind.harboe@zylin.com *
+ * *
* 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 2 of the License, or *
#endif
#include "bitbang.h"
+#include "interface.h"
+#include "commands.h"
-/* project specific includes */
-#include "log.h"
-#include "types.h"
-#include "jtag.h"
-#include "configuration.h"
-
-/* system includes */
-#include <string.h>
-#include <stdlib.h>
-#include <unistd.h>
+/**
+ * Function bitbang_stableclocks
+ * issues a number of clock cycles while staying in a stable state.
+ * Because the TMS value required to stay in the RESET state is a 1, whereas
+ * the TMS value required to stay in any of the other stable states is a 0,
+ * this function checks the current stable state to decide on the value of TMS
+ * to use.
+ */
+static void bitbang_stableclocks(int num_cycles);
-#include <sys/time.h>
-#include <time.h>
bitbang_interface_t *bitbang_interface;
-int bitbang_execute_queue(void);
-
-/* The bitbang driver leaves the TCK 0 when in idle */
+/* DANGER!!!! clock absolutely *MUST* be 0 in idle or reset won't work!
+ *
+ * Set this to 1 and str912 reset halt will fail.
+ *
+ * If someone can submit a patch with an explanation it will be greatly
+ * appreciated, but as far as I can tell (ØH) DCLK is generated upon
+ * clk = 0 in TAP_IDLE. Good luck deducing that from the ARM documentation!
+ * The ARM documentation uses the term "DCLK is asserted while in the TAP_IDLE
+ * state". With hardware there is no such thing as *while* in a state. There
+ * are only edges. So clk => 0 is in fact a very subtle state transition that
+ * happens *while* in the TAP_IDLE state. "#&¤"#¤&"#&"#&
+ *
+ * For "reset halt" the last thing that happens before srst is asserted
+ * is that the breakpoint is set up. If DCLK is not wiggled one last
+ * time before the reset, then the breakpoint is not set up and
+ * "reset halt" will fail to halt.
+ *
+ */
+#define CLOCK_IDLE() 0
-void bitbang_end_state(enum tap_state state)
+/* The bitbang driver leaves the TCK 0 when in idle */
+static void bitbang_end_state(tap_state_t state)
{
- if (tap_move_map[state] != -1)
- end_state = state;
+ if (tap_is_state_stable(state))
+ tap_set_end_state(state);
else
{
LOG_ERROR("BUG: %i is not a valid end state", state);
}
}
-void bitbang_state_move(void) {
-
- int i=0, tms=0;
- u8 tms_scan = TAP_MOVE(cur_state, end_state);
-
- for (i = 0; i < 7; i++)
+static void bitbang_state_move(int skip)
+{
+ int i = 0, tms = 0;
+ uint8_t tms_scan = tap_get_tms_path(tap_get_state(), tap_get_end_state());
+ int tms_count = tap_get_tms_path_len(tap_get_state(), tap_get_end_state());
+
+ for (i = skip; i < tms_count; i++)
{
tms = (tms_scan >> i) & 1;
bitbang_interface->write(0, tms, 0);
bitbang_interface->write(1, tms, 0);
}
- bitbang_interface->write(0, tms, 0);
-
- cur_state = end_state;
+ bitbang_interface->write(CLOCK_IDLE(), tms, 0);
+
+ tap_set_state(tap_get_end_state());
}
-void bitbang_path_move(pathmove_command_t *cmd)
+static void bitbang_path_move(pathmove_command_t *cmd)
{
int num_states = cmd->num_states;
int state_count;
state_count = 0;
while (num_states)
{
- if (tap_transitions[cur_state].low == cmd->path[state_count])
+ if (tap_state_transition(tap_get_state(), false) == cmd->path[state_count])
{
tms = 0;
}
- else if (tap_transitions[cur_state].high == cmd->path[state_count])
+ else if (tap_state_transition(tap_get_state(), true) == cmd->path[state_count])
{
tms = 1;
}
else
{
- LOG_ERROR("BUG: %s -> %s isn't a valid TAP transition", tap_state_strings[cur_state], tap_state_strings[cmd->path[state_count]]);
+ LOG_ERROR("BUG: %s -> %s isn't a valid TAP transition", tap_state_name(tap_get_state()), tap_state_name(cmd->path[state_count]));
exit(-1);
}
-
+
bitbang_interface->write(0, tms, 0);
bitbang_interface->write(1, tms, 0);
- cur_state = cmd->path[state_count];
+ tap_set_state(cmd->path[state_count]);
state_count++;
num_states--;
}
-
- bitbang_interface->write(0, tms, 0);
- end_state = cur_state;
+ bitbang_interface->write(CLOCK_IDLE(), tms, 0);
+
+ tap_set_end_state(tap_get_state());
}
-void bitbang_runtest(int num_cycles)
+static void bitbang_runtest(int num_cycles)
{
int i;
-
- enum tap_state saved_end_state = end_state;
-
- /* only do a state_move when we're not already in RTI */
- if (cur_state != TAP_RTI)
+
+ tap_state_t saved_end_state = tap_get_end_state();
+
+ /* only do a state_move when we're not already in IDLE */
+ if (tap_get_state() != TAP_IDLE)
{
- bitbang_end_state(TAP_RTI);
- bitbang_state_move();
+ bitbang_end_state(TAP_IDLE);
+ bitbang_state_move(0);
}
-
+
/* execute num_cycles */
- bitbang_interface->write(0, 0, 0);
for (i = 0; i < num_cycles; i++)
{
- bitbang_interface->write(1, 0, 0);
bitbang_interface->write(0, 0, 0);
+ bitbang_interface->write(1, 0, 0);
}
-
+ bitbang_interface->write(CLOCK_IDLE(), 0, 0);
+
/* finish in end_state */
bitbang_end_state(saved_end_state);
- if (cur_state != end_state)
- bitbang_state_move();
+ if (tap_get_state() != tap_get_end_state())
+ bitbang_state_move(0);
}
-void bitbang_scan(int ir_scan, enum scan_type type, u8 *buffer, int scan_size)
+
+static void bitbang_stableclocks(int num_cycles)
{
- enum tap_state saved_end_state = end_state;
+ int tms = (tap_get_state() == TAP_RESET ? 1 : 0);
+ int i;
+
+ /* send num_cycles clocks onto the cable */
+ for (i = 0; i < num_cycles; i++)
+ {
+ bitbang_interface->write(1, tms, 0);
+ bitbang_interface->write(0, tms, 0);
+ }
+}
+
+
+
+static void bitbang_scan(bool ir_scan, enum scan_type type, uint8_t *buffer, int scan_size)
+{
+ tap_state_t saved_end_state = tap_get_end_state();
int bit_cnt;
-
- if (!((!ir_scan && (cur_state == TAP_SD)) || (ir_scan && (cur_state == TAP_SI))))
+
+ if (!((!ir_scan && (tap_get_state() == TAP_DRSHIFT)) || (ir_scan && (tap_get_state() == TAP_IRSHIFT))))
{
if (ir_scan)
- bitbang_end_state(TAP_SI);
+ bitbang_end_state(TAP_IRSHIFT);
else
- bitbang_end_state(TAP_SD);
+ bitbang_end_state(TAP_DRSHIFT);
- bitbang_state_move();
+ bitbang_state_move(0);
bitbang_end_state(saved_end_state);
}
for (bit_cnt = 0; bit_cnt < scan_size; bit_cnt++)
{
+ int val = 0;
+ int tms = (bit_cnt == scan_size-1) ? 1 : 0;
+ int tdi;
+ int bytec = bit_cnt/8;
+ int bcval = 1 << (bit_cnt % 8);
+
/* if we're just reading the scan, but don't care about the output
* default to outputting 'low', this also makes valgrind traces more readable,
* as it removes the dependency on an uninitialised value
- */
- if ((type != SCAN_IN) && ((buffer[bit_cnt/8] >> (bit_cnt % 8)) & 0x1))
- {
- bitbang_interface->write(0, (bit_cnt==scan_size-1) ? 1 : 0, 1);
- bitbang_interface->write(1, (bit_cnt==scan_size-1) ? 1 : 0, 1);
- } else {
- bitbang_interface->write(0, (bit_cnt==scan_size-1) ? 1 : 0, 0);
- bitbang_interface->write(1, (bit_cnt==scan_size-1) ? 1 : 0, 0);
- }
-
+ */
+ tdi = 0;
+ if ((type != SCAN_IN) && (buffer[bytec] & bcval))
+ tdi = 1;
+
+ bitbang_interface->write(0, tms, tdi);
+
+ if (type != SCAN_OUT)
+ val = bitbang_interface->read();
+
+ bitbang_interface->write(1, tms, tdi);
+
if (type != SCAN_OUT)
{
- /*
- TDO should be sampled on the rising edge, and will change
- on the falling edge.
-
- Because there is no way to read the signal exactly at the rising edge,
- read after the rising edge.
-
- This is plain IEEE 1149 JTAG - nothing specific to the OpenOCD or its JTAG
- API.
- */
- if (bitbang_interface->read())
- buffer[(bit_cnt)/8] |= 1 << ((bit_cnt) % 8);
+ if (val)
+ buffer[bytec] |= bcval;
else
- buffer[(bit_cnt)/8] &= ~(1 << ((bit_cnt) % 8));
+ buffer[bytec] &= ~bcval;
}
}
-
- /* TAP_SD & TAP_SI are illegal end states, so we always transition to the pause
- * state which is a legal stable state from which statemove will work.
- *
- * Exit1 -> Pause
- */
- bitbang_interface->write(0, 0, 0);
- bitbang_interface->write(1, 0, 0);
- bitbang_interface->write(0, 0, 0);
-
- if (ir_scan)
- cur_state = TAP_PI;
- else
- cur_state = TAP_PD;
-
- if (cur_state != end_state)
- bitbang_state_move();
+
+ if (tap_get_state() != tap_get_end_state())
+ {
+ /* we *KNOW* the above loop transitioned out of
+ * the shift state, so we skip the first state
+ * and move directly to the end state.
+ */
+ bitbang_state_move(1);
+ }
}
int bitbang_execute_queue(void)
jtag_command_t *cmd = jtag_command_queue; /* currently processed command */
int scan_size;
enum scan_type type;
- u8 *buffer;
+ uint8_t *buffer;
int retval;
-
+
if (!bitbang_interface)
{
LOG_ERROR("BUG: Bitbang interface called, but not yet initialized");
exit(-1);
}
-
+
/* return ERROR_OK, unless a jtag_read_buffer returns a failed check
* that wasn't handled by a caller-provided error handler
- */
+ */
retval = ERROR_OK;
-
- if(bitbang_interface->blink)
+
+ if (bitbang_interface->blink)
bitbang_interface->blink(1);
while (cmd)
{
switch (cmd->type)
{
- case JTAG_END_STATE:
-#ifdef _DEBUG_JTAG_IO_
- LOG_DEBUG("end_state: %i", cmd->cmd.end_state->end_state);
-#endif
- if (cmd->cmd.end_state->end_state != -1)
- bitbang_end_state(cmd->cmd.end_state->end_state);
- break;
case JTAG_RESET:
#ifdef _DEBUG_JTAG_IO_
LOG_DEBUG("reset trst: %i srst %i", cmd->cmd.reset->trst, cmd->cmd.reset->srst);
#endif
- if (cmd->cmd.reset->trst == 1)
+ if ((cmd->cmd.reset->trst == 1) || (cmd->cmd.reset->srst && (jtag_get_reset_config() & RESET_SRST_PULLS_TRST)))
{
- cur_state = TAP_TLR;
+ tap_set_state(TAP_RESET);
}
bitbang_interface->reset(cmd->cmd.reset->trst, cmd->cmd.reset->srst);
break;
case JTAG_RUNTEST:
#ifdef _DEBUG_JTAG_IO_
- LOG_DEBUG("runtest %i cycles, end in %i", cmd->cmd.runtest->num_cycles, cmd->cmd.runtest->end_state);
+ LOG_DEBUG("runtest %i cycles, end in %s", cmd->cmd.runtest->num_cycles, tap_state_name(cmd->cmd.runtest->end_state));
#endif
- if (cmd->cmd.runtest->end_state != -1)
- bitbang_end_state(cmd->cmd.runtest->end_state);
+ bitbang_end_state(cmd->cmd.runtest->end_state);
bitbang_runtest(cmd->cmd.runtest->num_cycles);
break;
+
+ case JTAG_STABLECLOCKS:
+ /* this is only allowed while in a stable state. A check for a stable
+ * state was done in jtag_add_clocks()
+ */
+ bitbang_stableclocks(cmd->cmd.stableclocks->num_cycles);
+ break;
+
case JTAG_STATEMOVE:
#ifdef _DEBUG_JTAG_IO_
- LOG_DEBUG("statemove end in %i", cmd->cmd.statemove->end_state);
+ LOG_DEBUG("statemove end in %s", tap_state_name(cmd->cmd.statemove->end_state));
#endif
- if (cmd->cmd.statemove->end_state != -1)
- bitbang_end_state(cmd->cmd.statemove->end_state);
- bitbang_state_move();
+ bitbang_end_state(cmd->cmd.statemove->end_state);
+ bitbang_state_move(0);
break;
case JTAG_PATHMOVE:
#ifdef _DEBUG_JTAG_IO_
- LOG_DEBUG("pathmove: %i states, end in %i", cmd->cmd.pathmove->num_states, cmd->cmd.pathmove->path[cmd->cmd.pathmove->num_states - 1]);
+ LOG_DEBUG("pathmove: %i states, end in %s", cmd->cmd.pathmove->num_states,
+ tap_state_name(cmd->cmd.pathmove->path[cmd->cmd.pathmove->num_states - 1]));
#endif
bitbang_path_move(cmd->cmd.pathmove);
break;
case JTAG_SCAN:
#ifdef _DEBUG_JTAG_IO_
- LOG_DEBUG("%s scan end in %i", (cmd->cmd.scan->ir_scan) ? "IR" : "DR", cmd->cmd.scan->end_state);
+ LOG_DEBUG("%s scan end in %s", (cmd->cmd.scan->ir_scan) ? "IR" : "DR", tap_state_name(cmd->cmd.scan->end_state));
#endif
- if (cmd->cmd.scan->end_state != -1)
- bitbang_end_state(cmd->cmd.scan->end_state);
+ bitbang_end_state(cmd->cmd.scan->end_state);
scan_size = jtag_build_buffer(cmd->cmd.scan, &buffer);
type = jtag_scan_type(cmd->cmd.scan);
bitbang_scan(cmd->cmd.scan->ir_scan, type, buffer, scan_size);
}
cmd = cmd->next;
}
- if(bitbang_interface->blink)
+ if (bitbang_interface->blink)
bitbang_interface->blink(0);
-
+
return retval;
}
-
projects / fw / openocd / blobdiff