openocd/src/jtag/interface.h

385 lines
14 KiB
C

/***************************************************************************
* Copyright (C) 2005 by Dominic Rath *
* Dominic.Rath@gmx.de *
* *
* Copyright (C) 2007,2008 Øyvind Harboe *
* oyvind.harboe@zylin.com *
* *
* Copyright (C) 2009 Zachary T Welch *
* zw@superlucidity.net *
* *
* 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 *
* (at your option) any later version. *
* *
* This program is distributed in the hope that it will be useful, *
* but WITHOUT ANY WARRANTY; without even the implied warranty of *
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
* GNU General Public License for more details. *
* *
* You should have received a copy of the GNU General Public License *
* along with this program. If not, see <http://www.gnu.org/licenses/>. *
***************************************************************************/
#ifndef OPENOCD_JTAG_INTERFACE_H
#define OPENOCD_JTAG_INTERFACE_H
#include <jtag/jtag.h>
#include <jtag/swim.h>
#include <target/armv7m_trace.h>
/* @file
* The "Cable Helper API" is what the cable drivers can use to help
* implement their "Cable API". So a Cable Helper API is a set of
* helper functions used by cable drivers, and this is different from a
* Cable API. A "Cable API" is what higher level code used to talk to a
* cable.
*/
/* FIXME: prototype to simplify transition of HLA drivers. To be removed */
struct hl_interface_s;
/** implementation of wrapper function tap_set_state() */
void tap_set_state_impl(tap_state_t new_state);
/**
* This function sets the state of a "state follower" which tracks the
* state of the TAPs connected to the cable. The state follower is
* hopefully always in the same state as the actual TAPs in the jtag
* chain, and will be so if there are no bugs in the tracking logic
* within that cable driver.
*
* All the cable drivers call this function to indicate the state they
* think the TAPs attached to their cables are in. Because this
* function can also log transitions, it will be helpful to call this
* function with every transition that the TAPs being manipulated are
* expected to traverse, not just end points of a multi-step state path.
*
* @param new_state The state we think the TAPs are currently in (or
* are about to enter).
*/
#define tap_set_state(new_state) \
do { \
LOG_DEBUG_IO("tap_set_state(%s)", tap_state_name(new_state)); \
tap_set_state_impl(new_state); \
} while (0)
/**
* This function gets the state of the "state follower" which tracks the
* state of the TAPs connected to the cable. @see tap_set_state @return
* tap_state_t The state the TAPs are in now.
*/
tap_state_t tap_get_state(void);
/**
* This function sets the state of an "end state follower" which tracks
* the state that any cable driver thinks will be the end (resultant)
* state of the current TAP SIR or SDR operation.
*
* At completion of that TAP operation this value is copied into the
* state follower via tap_set_state().
*
* @param new_end_state The state the TAPs should enter at completion of
* a pending TAP operation.
*/
void tap_set_end_state(tap_state_t new_end_state);
/**
* For more information, @see tap_set_end_state
* @return tap_state_t - The state the TAPs should be in at completion of the current TAP operation.
*/
tap_state_t tap_get_end_state(void);
/**
* This function provides a "bit sequence" indicating what has to be
* done with TMS during a sequence of seven TAP clock cycles in order to
* get from state \a "from" to state \a "to".
*
* The length of the sequence must be determined with a parallel call to
* tap_get_tms_path_len().
*
* @param from The starting state.
* @param to The desired final state.
* @return int The required TMS bit sequence, with the first bit in the
* sequence at bit 0.
*/
int tap_get_tms_path(tap_state_t from, tap_state_t to);
/**
* Function int tap_get_tms_path_len
* returns the total number of bits that represents a TMS path
* transition as given by the function tap_get_tms_path().
*
* For at least one interface (JLink) it's not OK to simply "pad" TMS
* sequences to fit a whole byte. (I suspect this is a general TAP
* problem within OOCD.) Padding TMS causes all manner of instability
* that's not easily discovered. Using this routine we can apply
* EXACTLY the state transitions required to make something work - no
* more - no less.
*
* @param from is the starting state
* @param to is the resultant or final state
* @return int - the total number of bits in a transition.
*/
int tap_get_tms_path_len(tap_state_t from, tap_state_t to);
/**
* Function tap_move_ndx
* when given a stable state, returns an index from 0-5. The index corresponds to a
* sequence of stable states which are given in this order: <p>
* { TAP_RESET, TAP_IDLE, TAP_DRSHIFT, TAP_DRPAUSE, TAP_IRSHIFT, TAP_IRPAUSE }
* <p>
* This sequence corresponds to look up tables which are used in some of the
* cable drivers.
* @param astate is the stable state to find in the sequence. If a non stable
* state is passed, this may cause the program to output an error message
* and terminate.
* @return int - the array (or sequence) index as described above
*/
int tap_move_ndx(tap_state_t astate);
/**
* Function tap_is_state_stable
* returns true if the \a astate is stable.
*/
bool tap_is_state_stable(tap_state_t astate);
/**
* Function tap_state_transition
* takes a current TAP state and returns the next state according to the tms value.
* @param current_state is the state of a TAP currently.
* @param tms is either zero or non-zero, just like a real TMS line in a jtag interface.
* @return tap_state_t - the next state a TAP would enter.
*/
tap_state_t tap_state_transition(tap_state_t current_state, bool tms);
/** Allow switching between old and new TMS tables. @see tap_get_tms_path */
void tap_use_new_tms_table(bool use_new);
/** @returns True if new TMS table is active; false otherwise. */
bool tap_uses_new_tms_table(void);
/**
* @brief Prints verbose TAP state transitions for the given TMS/TDI buffers.
* @param tms_buf must points to a buffer containing the TMS bitstream.
* @param tdi_buf must points to a buffer containing the TDI bitstream.
* @param tap_len must specify the length of the TMS/TDI bitstreams.
* @param start_tap_state must specify the current TAP state.
* @returns the final TAP state; pass as @a start_tap_state in following call.
*/
static inline tap_state_t jtag_debug_state_machine(const void *tms_buf,
const void *tdi_buf, unsigned tap_len, tap_state_t start_tap_state)
{
/* Private declaration */
tap_state_t jtag_debug_state_machine_(const void *tms_buf, const void *tdi_buf,
unsigned tap_len, tap_state_t start_tap_state);
if (LOG_LEVEL_IS(LOG_LVL_DEBUG_IO))
return jtag_debug_state_machine_(tms_buf, tdi_buf, tap_len, start_tap_state);
else
return start_tap_state;
}
/**
* Represents a driver for a debugging interface.
*
* @todo Rename; perhaps "debug_driver". This isn't an interface,
* it's a driver! Also, not all drivers support JTAG.
*
* @todo We need a per-instance structure too, and changes to pass
* that structure to the driver. Instances can for example be in
* either SWD or JTAG modes. This will help remove globals, and
* eventually to cope with systems which have more than one such
* debugging interface.
*/
struct jtag_interface {
/**
* Bit vector listing capabilities exposed by this driver.
*/
unsigned supported;
#define DEBUG_CAP_TMS_SEQ (1 << 0)
/**
* Execute queued commands.
* @returns ERROR_OK on success, or an error code on failure.
*/
int (*execute_queue)(void);
};
/**
* Represents a driver for a debugging interface
*
* @todo We need a per-instance structure too, and changes to pass
* that structure to the driver. Instances can for example be in
* either SWD or JTAG modes. This will help remove globals, and
* eventually to cope with systems which have more than one such
* debugging interface.
*/
struct adapter_driver {
/** The name of the interface driver. */
const char * const name;
/** transports supported in C code (NULL terminated vector) */
const char * const *transports;
/**
* The interface driver may register additional commands to expose
* additional features not covered by the standard command set.
*/
const struct command_registration *commands;
/**
* Interface driver must initialize any resources and connect to a
* JTAG device.
*
* quit() is invoked if and only if init() succeeds. quit() is always
* invoked if init() succeeds. Same as malloc() + free(). Always
* invoke free() if malloc() succeeds and do not invoke free()
* otherwise.
*
* @returns ERROR_OK on success, or an error code on failure.
*/
int (*init)(void);
/**
* Interface driver must tear down all resources and disconnect from
* the JTAG device.
*
* @returns ERROR_OK on success, or an error code on failure.
*/
int (*quit)(void);
/**
* Control (assert/deassert) the signals SRST and TRST on the interface.
* This function is synchronous and should be called after the adapter
* queue has been properly flushed.
* This function is optional.
* Adapters that don't support resets can either not define this function
* or return an error code.
* Adapters that don't support one of the two reset should ignore the
* request to assert the missing signal and eventually log an error.
*
* @param srst 1 to assert SRST, 0 to deassert SRST.
* @param trst 1 to assert TRST, 0 to deassert TRST.
* @returns ERROR_OK on success, or an error code on failure.
*/
int (*reset)(int srst, int trst);
/**
* Set the interface speed.
* @param speed The new interface speed setting.
* @returns ERROR_OK on success, or an error code on failure.
*/
int (*speed)(int speed);
/**
* Returns JTAG maxium speed for KHz. 0 = RTCK. The function returns
* a failure if it can't support the KHz/RTCK.
*
* WARNING!!!! if RTCK is *slow* then think carefully about
* whether you actually want to support this in the driver.
* Many target scripts are written to handle the absence of RTCK
* and use a fallback kHz TCK.
* @returns ERROR_OK on success, or an error code on failure.
*/
int (*khz)(int khz, int *jtag_speed);
/**
* Calculate the clock frequency (in KHz) for the given @a speed.
* @param speed The desired interface speed setting.
* @param khz On return, contains the speed in KHz (0 for RTCK).
* @returns ERROR_OK on success, or an error code if the
* interface cannot support the specified speed (KHz or RTCK).
*/
int (*speed_div)(int speed, int *khz);
/**
* Read and clear the power dropout flag. Note that a power dropout
* can be transitionary, easily much less than a ms.
*
* To find out if the power is *currently* on, one must invoke this
* method twice. Once to clear the power dropout flag and a second
* time to read the current state. The default implementation
* never reports power dropouts.
*
* @returns ERROR_OK on success, or an error code on failure.
*/
int (*power_dropout)(int *power_dropout);
/**
* Read and clear the srst asserted detection flag.
*
* Like power_dropout this does *not* read the current
* state. SRST assertion is transitionary and may be much
* less than 1ms, so the interface driver must watch for these
* events until this routine is called.
*
* @param srst_asserted On return, indicates whether SRST has
* been asserted.
* @returns ERROR_OK on success, or an error code on failure.
*/
int (*srst_asserted)(int *srst_asserted);
/**
* Configure trace parameters for the adapter
*
* @param enabled Whether to enable trace
* @param pin_protocol Configured pin protocol
* @param port_size Trace port width for sync mode
* @param trace_freq A pointer to the configured trace
* frequency; if it points to 0, the adapter driver must write
* its maximum supported rate there
* @param traceclkin_freq TRACECLKIN frequency provided to the TPIU in Hz
* @param prescaler Pointer to the SWO prescaler calculated by the
* adapter
* @returns ERROR_OK on success, an error code on failure.
*/
int (*config_trace)(bool enabled, enum tpiu_pin_protocol pin_protocol,
uint32_t port_size, unsigned int *trace_freq,
unsigned int traceclkin_freq, uint16_t *prescaler);
/**
* Poll for new trace data
*
* @param buf A pointer to buffer to store received data
* @param size A pointer to buffer size; must be filled with
* the actual amount of bytes written
*
* @returns ERROR_OK on success, an error code on failure.
*/
int (*poll_trace)(uint8_t *buf, size_t *size);
/** Low-level JTAG APIs */
struct jtag_interface *jtag_ops;
/** Low-level SWD APIs */
const struct swd_driver *swd_ops;
/* DAP APIs over JTAG transport */
const struct dap_ops *dap_jtag_ops;
/* DAP APIs over SWD transport */
const struct dap_ops *dap_swd_ops;
/* SWIM APIs */
const struct swim_driver *swim_ops;
/* FIXME: helper to simplify transition of HLA drivers. To be removed */
struct hl_interface_s *hla_if;
};
extern const char * const jtag_only[];
int adapter_resets(int assert_trst, int assert_srst);
int adapter_assert_reset(void);
int adapter_deassert_reset(void);
int adapter_config_trace(bool enabled, enum tpiu_pin_protocol pin_protocol,
uint32_t port_size, unsigned int *trace_freq,
unsigned int traceclkin_freq, uint16_t *prescaler);
int adapter_poll_trace(uint8_t *buf, size_t *size);
#endif /* OPENOCD_JTAG_INTERFACE_H */