comments for Luminary ICDI layout

Provide $defines for more of the signals involved in the
Luminary ICDI hardware, and comment some of what's going on.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
This commit is contained in:
David Brownell 2010-07-18 17:29:25 -04:00 committed by David Brownell
parent b85dcae447
commit d10f0def80
1 changed files with 27 additions and 3 deletions

View File

@ -318,6 +318,9 @@ static const struct ft2232_layout *layout;
/** default bitmask values ddriven on DBUS: TCK/TDI/TDO/TMS and GPIOL(0..4) */
static uint8_t low_output = 0x0;
/* note that direction bit == 1 means that signal is an output */
/** default direction bitmask for DBUS: TCK/TDI/TDO/TMS and GPIOL(0..4) */
static uint8_t low_direction = 0x0;
/** default value bitmask for CBUS GPIOH(0..4) */
@ -2492,13 +2495,34 @@ static int icdi_jtag_init(void)
/* Most Luminary eval boards support SWO trace output,
* and should use this "luminary_icdi" layout.
*
* DBUS 0..3 are used for JTAG as usual. GPIOs are used
* to switch between JTAG and SWD, or switch the ft2232 UART
* between (i) the target UART or (ii) SWO trace data.
*
* We come up in JTAG mode and may switch to SWD later (with
* SWO/trace option if SWD is active).
*
* DBUS == GPIO-Lx
* CBUS == GPIO-Hx
*/
#define ICDI_JTAG_EN (1 << 7) /* ADBUS 7 (a.k.a. DBGMOD) */
#define ICDI_DBG_ENn (1 << 6) /* ADBUS 6 */
#define ICDI_SRST (1 << 5) /* ADBUS 5 */
#define ICDI_TDI (1 << 2) /* ADBUS 2 (INPUT) */
#define ICDI_SWO_EN (1 << 4) /* BDBUS 4 */
#define ICDI_TX_SWO (1 << 1) /* BDBUS 1 */
nTRST = 0x0;
nTRSTnOE = 0x00;
nSRST = 0x20;
nSRST = ICDI_SRST;
nSRSTnOE = 0x20;
low_output = 0x88;
low_direction = 0xcb;
low_output = 0x08 | ICDI_JTAG_EN;
low_direction = 0xcb | ICDI_JTAG_EN;
return ftx232_dbus_write();
}