On 11/21/2015 09:59 PM, Soren Brinkmann wrote:

Hi,

here is v3 of this series. It's largely the same as before, but I
adjusted 'tty: xuartps: Don't consider circular buffer when enabling
transmitter' according to Peter's suggestions.

In reviewing this series, I thought the _OFFSET suffix for every register
address to be excessive. I would refactor all that out; IOW,

-	isrstatus = readl(port->membase + CDNS_UART_ISR_OFFSET);
+	isrstatus = readl(port->membase + CDNS_UART_ISR);

I also spent some time trying to get Peter's test for flow control and
xchar running. The xchar thing fails and will need some more work, but I
think in general it should be possible to get it to work.
The flow control test passes:

root@Xilinx-ZC1751-DC1:~# ./flow /dev/ttyPS0
Test flow control on /dev/ttyPS0
begin test1
patterns sent: 223  recvd: 208
read distribution: 1   = 0
                   2+  = 0
                   4+  = 0
                   8+  = 0
                  16+  = 0
                  32+  = 643
                  64+  = 0
                 128+  = 0
                 256+  = 0
                 512+  = 0
PASSED

This distribution looks like this exactly because the xchar test is
failing. IOW, this driver isn't performing soft flow control (^S,^Q)
like it should.

Regards,
Peter Hurley

root@Xilinx-ZC1751-DC1:~# ./flow /dev/ttyPS1
Test flow control on /dev/ttyPS1
begin test1
patterns sent: 223  recvd: 208
read distribution: 1   = 0
                   2+  = 0
                   4+  = 0
                   8+  = 0
                  16+  = 0
                  32+  = 643
                  64+  = 0
                 128+  = 0
                 256+  = 0
                 512+  = 0
PASSED

	Sören

Sören Brinkmann (10):
  tty: xuartps: Beautify read-modify writes
  tty: xuartps: Use spinlock to serialize HW access
  tty: xuartps: Don't consider circular buffer when enabling transmitter
  tty: xuartps: Clear interrupt status register in shutdown
  tty: xuartps: Improve startup function
  tty: xuartps: Keep lock for whole ISR
  tty: xuartps: Acquire port lock for shutdown
  tty: xuartps: Move RX path into helper function
  tty: xuartps: Only handle RX IRQs when RX is enabled
  tty: xuartps: Cleanup: Reformat if-else

 drivers/tty/serial/xilinx_uartps.c | 246 +++++++++++++++++++++----------------
 1 file changed, 137 insertions(+), 109 deletions(-)