On Fri, Nov 16, 2012 at 11:08 PM, Lauri Hintsala <lauri.hintsala@xxxxxxxxxxxx> wrote: > Hi Huang, > > Thanks for new version. Now I don't get any errors and the CPU doesn't > freeze any more but: > > 1) AUART corrupts data with baudrate over 1Mbits/s The tranceivers, such as MAX3380E, will limit the speed. i ever removed it, and tested the AUART in 3M bits/s. > > 2) We would need DMA support without flow control. :) I really think it's not wise to support the DMA withou flow control. it will losts the data in some case. Even use the FREESCALE's bsp code, I also recomand to use the flow control. > > By the way, how do you test drivers? Is there any standard tools for uart > data and throughput testing? I tested the driver with our own small tool. If you want to test it too, I can send you the resource next monday. You can use it to test if you have received the right data. thanks Huang Shijie > > Lauri > > > On 11/16/2012 10:03 AM, Huang Shijie wrote: >> >> This patch set adds the DMA support for auart in mx28. >> patch 1: >> In mx23, the DMA has a bug(see errata:2836). We can not add the >> DMA support in mx23, but we can add DMA support to auart in mx28. >> So in order to add the DMA support for the auart in mx28, we >> should add >> the platform_device_id to distinguish the distinguish SOCs. >> >> patch 2: add the DMA support for mx28 >> Only we meet the following conditions, we can enable the DMA >> support >> for auart: >> (1) We enable the DMA support in the dts file, such as >> arch/arm/boot/dts/imx28.dtsi. >> (2) We enable the hardware flow control. >> (3) We use the mx28, not the mx23. Due to hardware bug(see >> errata: 2836), >> we can not add the DMA support to mx23. >> >> patch 3: enable the DMA support in dts for mx28 >> You can use the /ttyAPP0 to test this patch set. >> I tested this patch in mx28-evk board. >> >> >> To Lauri: Please try this patch set. thanks. >> >> >> v2 --> v3: >> [1] fix a multi-open issue found by Lauri. >> >> v1 --> v2: >> [1] use the inline function, not a macro, to distinguish the SOCs. >> [2] remove the "inline" for mxs_auart_tx_chars(). >> [3] use the `pio`, not the `pio[1]` to fill the DMA descriptor. >> [4] use bit operation to serialize the DMA TX. >> [5] use the RX/TX DMA channel to enable the DMA support, remove >> the >> "fsl,auart-enable-dma". >> >> Huang Shijie (3): >> serial: mxs-auart: distinguish the different SOCs >> serial: mxs-auart: add the DMA support for mx28 >> ARM: dts: enable dma support for auart0 in mx28 >> >> .../bindings/tty/serial/fsl-mxs-auart.txt | 8 + >> arch/arm/boot/dts/imx28.dtsi | 1 + >> drivers/tty/serial/mxs-auart.c | 364 >> +++++++++++++++++++- >> 3 files changed, 362 insertions(+), 11 deletions(-) >> >> > -- > To unsubscribe from this list: send the line "unsubscribe linux-serial" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
