Kernel UART
From OMAPpedia
Overview
This page describes the HSUART software development effort for OMAP3 and OMAP4 platforms. The purpose is to provide information on the current status and features planned in the road map.
List of Features Supported
NUMBER OF UART PORTS AVAILABLE:
On OMAP3430: 3
On OMAP3630/OMAP4: 4
Its supports following feature:
· 64-byte FIFO for receiver and 64-byte FIFO for transmitter
· Programmable interrupt trigger levels for FIFOs
· Configurable data format
· Data bit: 5, 6, 7, or 8 bits · Parity bit: Even, odd, none · Stop-bit: 1, 1.5, 2 bit(s)
· Flow control: Hardware (RTS/CTS) or software (XON/XOFF)
· Supports baudrate from 300bps upto 3.6M bits/s.
· Supports DMA Mode for all UARTs
 OMAP3 HSUART Block Diagram |
 OMAP4 HSUART Block Diagram |
Patches merged in kernel.org
Recent submissions to open-source
Omap-serial driver with platform data support form Kevin's PM tree wip-uart branch
https://patchwork.kernel.org/patch/101874/
Hwmod stabilization on wip-uart branch in Kevin's PM Tree.
https://patchwork.kernel.org/patch/101867/
https://patchwork.kernel.org/patch/101188/
https://patchwork.kernel.org/patch/101189/
https://patchwork.kernel.org/patch/101190/
https://patchwork.kernel.org/patch/101191/
https://patchwork.kernel.org/patch/101192/
https://patchwork.kernel.org/patch/101193/
Current status of OMAP4 patches in omapzoom tree
GIT tree location:
http://dev.omapzoom.org/?p=integration/kernel-omap4.git;a=summary
Features under development
- HWMOD adaptations.
Future Development Plan
- support runtime pm using dev-pm-ops.
Reference:
http://www.elinux.org/images/0/08/ELC-2010-Hilman-Runtime-PM.pdf
http://lwn.net/Articles/347575/
http://lwn.net/Articles/347573/
Information on HSUART Testing procedures
[The below page needs some updation]
Reference:
http://elinux.org/OMAP_UART_pm_debugging
To test on 4430SDP:
We need to use the J14 expansion connector.
Pinouts details:
Connection J14 Expansion connector UART2 loopback:
UART2-------SDP4430---------J14I,J14J------------ I2[UART2_CTS] I3[UART2_RTS] J1[UART2_RX] J2[UART2_TX]
Use small peices of wires and short cts to rts and tx to rx.
Other details:
Building HS-UART Test suite on DDT branch:
make distclean
export TESTSUITES="hsuart"
export KDIR=/home/govindraj/clones/omap4/kernel-omap4-base
export HOST=arm-none-linux-gnueabi
export CROSS_COMPILE=arm-none-linux-gnueabi-
export ARCH=arm
make
Testing on Target:
export PATH=$PATH:/build/utils/handlers:/build/utils/bin:/build/hsuart/scripts/helper
export HSUART_DIR_TMP=/build/hsuart/scripts/tmp
export HSUART_DIR_BINARIES=/build/hsuart/bin
export UART_TEST_PORT1='ttyO1'
[ I am assuming you are using omap-serial driver if you are using 8250 driver then export uart test port as ttyS1]
Submit your ideas here
Owner
Govindraj.R <govindraj.raja at ti dot com>
