This is required for FDT's standard "reg-io-width" property
(similar to "reg-shift" property) found in many DTS files.
This fixes operation on Altera Arria 10 SOC Development Kit,
where standard ns8250 uart allows 4-byte access only.
Reviewed by: kan, marcel
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D9785
The QUICC engine is found on various Freescale parts including MPC85xx, and
provides multiple generic time-division serial channel resources, which are in
turn muxed/demuxed by the Serial Communications Controller (SCC).
Along with core QUICC/SCC functionality a uart(4)-compliant device driver is
provided which allows for serial ports over QUICC/SCC.
Approved by: cognet (mentor)
Obtained from: Juniper
MFp4: e500
controllers typically have multiple channels and support a number
of serial communications protocols. The scc(4) driver is itself
an umbrella driver that delegates the control over each channel
and mode to a subordinate driver (like uart(4)).
The scc(4) driver supports the Siemens SAB 82532 and the Zilog
Z8530 and replaces puc(4) for these devices.