Hi,
On 18/01/2019 11:48, Sai Prakash Ranjan wrote:
Hi Suzuki,
On 1/18/2019 4:27 PM, Suzuki K Poulose wrote:
If you want to use the scatter-gather mode, you must add
"arm,scatter-gather"
property to the node here.
Have you tested the scatter-gather mode on the chip ? Does that work at
all ?
Note: You could try this by setting a buffer_size > 1M for the ETR and use
it as a sink from the sysfs mode.
Yes the chip supports scatter-gather mode[1]. But is it required in
dt node since it's an optional property?
If you would like to use the scatter-gather mode, you must specify it
explicitly. We have had some other boards with broken scatter-gather
mode integration which causes mysterious issues when used. So we have
a white-list approach for enabling the scatter-gather mode in the driver.
So, if you have tested to make sure that the mode works fine with a recent
kernel version (v4.19 onwards), you may want to add the property.
Suzuki
