Re: [PATCH 09/16] tty: serial: 8250_dma: Add a TX trigger workaround for AM33xx

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 09/11/2014 01:42 PM, Sebastian Andrzej Siewior wrote:
>> We should add hooks like tx_dma and rx_dma to struct uart_8250_dma so
>> that the probe drivers can replace serial8250_tx_dma and
>> seria8250_rx_dma, like I think Alan already suggested.
> 
> Okay. Wasn't aware that Alan already suggested that.
> I also need a watchdog timer for TX since it seems that on omap3 the
> DMA engine suddenly forgets to continue with DMA…
> 
> If this is really what we want, I would need to refactor a few things…
> 
>> Let's keep serial8250_tx_dma/rx_dma as the default, and not add any
>> quirks to them. Only if there is a very common case should it be
>> handled in those. The case of RX req needing to be sent before data in
>> FIFO maybe one of those, but I'm no sure.
> 
> keep in mind that both (RX & TX bugs/hacks) need also a bit of handling
> in the 8250-core so it works together (like the tx_err member so we
> fall back to manual xmit)

Done. I've kept the RX workarounds in the 8250_dma and moved the TX
part into the omap driver.
I needed to add the 8250_core pieces of patch #10 [0]. Now If you say,
couldn't this done in an other way then I could move the RX workarounds
pieces to the omap driver as well as the interrupt routine. Any
preferences?

[0] [PATCH 10/16] tty: serial: 8250_dma: optimize the xmit path due to
    UART_BUG_DMA_TX

Sebastian

--
To unsubscribe from this list: send the line "unsubscribe linux-omap" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [Linux Arm (vger)]     [ARM Kernel]     [ARM MSM]     [Linux Tegra]     [Linux WPAN Networking]     [Linux Wireless Networking]     [Maemo Users]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Trails]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux