Commit Graph

4 Commits

Author SHA1 Message Date
Alex Elder
f45a7bccdc net: ipa: don't be a hog in gsi_channel_poll()
The iteration count value used in gsi_channel_poll() is intended to
limit poll iterations to the budget supplied as an argument.  But
it's never updated.

Fix this bug by incrementing the count each time through the loop.

Reported-by: Sharath Chandra Vurukala <sharathv@codeaurora.com>
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-16 15:14:54 -07:00
Alex Elder
0b1ba18aec net: ipa: zero return code before issuing generic EE command
Zero the result code stored in a field of the scratch 0 register
before issuing a generic EE command.  This just guarantees that
the value we read later was actually written as a result of the
command.

Also add the definitions of two more possible result codes that can
be returned when issuing flow control enable or disable commands:
  INCORRECT_CHANNEL_STATE: - channel must be in started state
  INCORRECT_DIRECTION - flow control is only valid for TX channels

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-30 18:04:58 -07:00
Alex Elder
0721999f15 net: ipa: fix an error message in gsi_channel_init_one()
An error message about limiting the number of TREs used prints the
wrong value.  Fix this bug.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-30 18:04:58 -07:00
Alex Elder
650d160382 soc: qcom: ipa: the generic software interface
This patch includes "gsi.c", which implements the generic software
interface (GSI) for IPA.  The generic software interface abstracts
channels, which provide a means of transferring data either from the
AP to the IPA, or from the IPA to the AP.  A ring buffer of "transfer
elements" (TREs) is used to describe data transfers to perform.  The
AP writes a doorbell register associated with a channel to let it know
it has added new entries (for an AP->IPA channel) or has finished
processing entries (for an IPA->AP channel).

Each channel also has an event ring buffer, used by the IPA to
communicate information about events related to a channel (for
example, the completion of TREs).  The IPA writes its own doorbell
register, which triggers an interrupt on the AP, to signal that
new event information has arrived.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-08 22:07:09 -07:00