On 01/26/16 20:27, Stephen Warren wrote:

On 01/26/2016 09:59 AM, Ralf Ramsauer wrote:

quoted

This patch enables the APB DMA high speed UARTs of the Jetson TK1. So
far, they were only enabled in NVidia's official BSP.

Those additional UARTs are exposed on the expansion connector J3A2:

  UART1:
   Pin 41: BR_UART1_TXD
   Pin 44: BR_UART1_RXD

  UART2:
   Pin 65: UART2_RXD
   Pin 68: UART2_TXD
   Pin 71: UART2_CTS_L
   Pin 74: UART2_RTS_L

The series,
Acked-by: Stephen Warren <redacted>


As an aside, this is perfectly OK, but I wonder why you chose to use
compatible=nvidia,tegra124-hsuart rather than
compatible=nvidia,tegra124-uart. The -hsuart driver has had less
testing upstream, whereas the regular -uart driver is heavily used for
the main serial console. I assume you tested the new driver when
enabling the ports:-)

Let me explain it, this is how I found the typos :-)

tegra124.dtsi states:
    /*
     * There are two serial driver i.e. 8250 based simple serial
     * driver and APB DMA based serial driver for higher baudrate
     * and performace. To enable the 8250 based driver, the compatible
     * is "nvidia,tegra124-uart", "nvidia,tegra20-uart" and to enable
     * the APB DMA based serial driver, the compatible is
     * "nvidia,tegra124-hsuart", "nvidia,tegra30-hsuart".
     */

There's nothing written about the upstream stability of the hsuart
driver. So I didn't even try to use the non-hs uart driver. Nevertheless
I successfully tested both additional uarts using the hsuart driver
against 4.5-rc1 and some uart-speaking device.

  Ralf

-- 
Ralf Ramsauer
GPG: 0x8F10049B