On 06/22/2010 09:28 AM, Chuck Meade wrote:
Hi Gary,
According to the errata, it looks like the MPC8358 is subject to
erratum QE_UART6. You'll need to use soft UART mode and load the
microcode patch. Once that is done you will also need to use two
different BRG's, one for tx and one for rx, since the soft UART mode
microcode patch requires them to be set to different rates (I believe
Rx is 16*baud under soft UART mode, and Tx is 1*baud).
As I feared! Can you tell me where/how to get the microcode patch?
Also, I don't know if it matters or not, but you should change your
dts entry "ser...@4000" to "ser...@2200", just like you recently changed
your "reg =" to 0x2200.
I did that as soon as I sent this and saw the glaring inconsistency :-)
Thanks
Sure. Go to opensource.freescale.com/firmware and download (for your MPC8358)
the 8360 soft UART mode microcode patch. You will need to know if your CPU
is a 2.0 or 2.1 silicon, since there is a different microcode patch for each.
Then in the kernel config I believe I included CONFIG_FW_LOADER and
CONFIG_HOTPLUG
(one of those may have autoselected the other).
Make sure in your ucc_uart.c driver that soft uart mode is enabled.
At boot time, the driver will kick off a 10 second timer that will expect
the microcode patch to be loaded before the end of that 10 secs.
Very early in my boot sequence, I have a startup script send the microcode patch
file to the driver through the firmware-loading sysfs entry. But you need to
be aware that the UCC number in the sysfs path will be offset by one. Since you
are using UCC3, you should use a '2' in the path as shown below. This sequence
worked for me (I changed the number for you to '2' in my command sequence, since
I use a different UCC):
echo 1> /sys/class/firmware/fsl-ucc-uart2/loading
cat /root/fsl_qe_ucode_uart_8360_21.bin>
/sys/class/firmware/fsl-ucc-uart2/data
echo 0> /sys/class/firmware/fsl-ucc-uart2/loading
Note that the above presupposes you are using the file for silicon 2.1.
Also presupposes that you have put the microcode under your rootfs /root
directory.
Thanks, I'll give this a try. When I download the firmware this way,
do I need to follow the directions in
Documentation/powerpc/dts-bindings/fsl/cpm_qe/qe/firmware.txt
--
------------------------------------------------------------
Gary Thomas | Consulting for the
MLB Associates | Embedded world
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