auracaster/openocd
3
0
Fork 1
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

swd: get rid of jtag queue to assert/deassert srst

Browse Source 
The transport SWD uses the JTAG queue to assert/deassert the
system reset srst. This is the major inconsistency that has to be
removed to properly split JTAG and SWD.

Introduce a new driver API, reset(), to controls both the signals
trst and srst in the driver, skipping the JTAG queue. Put the new
API in struct jtag_interface, even if in this patch it's used for
SWD only; the goal is to get it reused by the other transports.

Add the implementation of the API in all the drivers that
implement SWD. Such implementation is almost the same of the old
code in JTAG queue.

Create a wrapper adapter_system_reset() to use the new API and
remove the SWD specific swd_add_reset(). In the wrapper replace
jtag_add_sleep() with jtag_sleep(), because the former uses the
JTAG queue too.
Rename the old jtag_add_reset() as legacy_jtag_add_reset() with
the target to remove it when all drivers would be ported to the
new reset API. Create a new jtag_add_reset() that calls the
legacy function for drivers still on the old reset API.

Use the new API also on JTAG transport for the drivers that can
support both SWD and JTAG.

For the moment, do not modify the implementation of JTAG-only
drivers, which will continue using the usual method. This should
be cleaned-up in future commits.

Change-Id: I32331c88313f6059b25e12c6bb0156aebc1c074f
Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Reviewed-on: http://openocd.zylin.com/4895
Tested-by: jenkins
Reviewed-by: Tomas Vanek <vanekt@fbl.cz>
This commit is contained in:
Antonio Borneo
2019-08-31 11:08:16 +02:00
committed by Tomas Vanek
parent db23c13d42
commit 8850eb8f2c
14 changed files with 233 additions and 144 deletions
Download Patch File Download Diff File Expand all files Collapse all files

14
src/jtag/interface.h
View File

@@ -246,6 +246,20 @@ struct jtag_interface {
*/
int (*quit)(void);
/**
* Control (assert/deassert) the signals SRST and TRST on the interface.
* 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);
/**
* Returns JTAG maxium speed for KHz. 0 = RTCK. The function returns
* a failure if it can't support the KHz/RTCK.