gdb-server: L0xx has no FP_CTRL register for breakpoints

[ghost]

There is no FP_CTRL register on the L0xx. In gdb-server.c, you have:

static void init_code_breakpoints(stlink_t *sl) {
    memset(sl->q_buf, 0, 4);
    stlink_write_debug32(sl, CM3_REG_FP_CTRL, 0x03 /*KEY | ENABLE4*/);
    if(...){
        ELOG("[FP_CTRL] = 0x%08x expecting 0x%08x\n", val,
    ...
    }
    ...
}

This causes the following error in st-util output:

$ ./st-util
2014-10-14T13:33:23 INFO src/stlink-common.c: Loading device parameters....
2014-10-14T13:33:23 INFO src/stlink-common.c: Device connected is: L0x3 device
...
2014-10-14T13:33:23 INFO gdbserver/gdb-server.c: Listening at *:4242...
2014-10-14T13:33:39 ERROR gdbserver/gdb-server.c: [FP_CTRL] = 0x00000041 expecting 0x00000261

The FPB and its registers have been replaced by the BPU on the M0 chips. Please see the ARM Info Center and its section on BPU functionality in the Debug section of the "Cortex M0 Technical Reference Manual".

[xor-gate]

Should work with latest 1.4.0 release.

[Nightwalker-87]

Closed by #341.