• SYSIO4: PB4 or TDI Assignment
0: TDI function selected.
1: PB4 function selected.
• SYSIO5: PB5 or TDO/TRACESWO Assignment
0: TDO/TRACESWO function selected.
1: PB5 function selected.
• SYSIO6: PB6 or TMS/SWDIO Assignment
0: TMS/SWDIO function selected.
1: PB6 function selected.
• SYSIO7: PB7 or TCK/SWCLK Assignment
0: TCK/SWCLK function selected.
1: PB7 function selected.
• SYSIO12: PB12 or ERASE Assignment
0: ERASE function selected.
1: PB12 function selected.

The thing I did not add is warning or compilation failure, (to save the next guy the hassle), at ALL the driver points that uses the these pins.

I did remove this

  /* To use the USART1 as an USART, the SYSIO Pin4 must be bound to PB4
   * instead of TDI
   */

  uint32_t sysioreg = getreg32(SAM_MATRIX_CCFG_SYSIO);
  sysioreg |= MATRIX_CCFG_SYSIO_SYSIO4;
  putreg32(sysioreg, SAM_MATRIX_CCFG_SYSIO);

in sam_lowputc.c in favor of an #error - because the default is an input TDI and driving it blindly to an output TXD1, would be a contention.

CAN support for STM32L4

SAM WDT: Rename up_wdginitialize() functions to something more appropriate for the internal OS interface.

SAM WDT: Rename up_wdginitialize() functions to something more appropriate for the internal OS interface.

enter/leave_critical_section:  In SMP configuration, may attempt to access the task lists before they have been initialized

Fixed Break changes needed CONFIG_SERIAL_TERMIOS to build

Upstream_to_greg

All GCC final arch/*/src/Makefiles: Allow --start-group and --end-group to be redefined for the case where GCC is used to link (instead of LD).  Suggested by Paul Alexander Patience.

wfi.mac should be copied into the directory with the IAR project. Then set it to "Options -> Debugger -> Setup macro file(s)". This will allow debugging via JTAG when calling the WFI instruction.