2022-11-28 06:25:43

by Sherry Sun

Subject: [PATCH] tty: serial: fsl_lpuart: don't enable receiver/transmitter before rx/tx dma ready

lpuart32_setup_watermark_enable() will configure the UART FIFO and
watermark, also enable the receiver and transmitter, this should be done
after the rx/tx dma steup ready.

Also add lpuart32_hw_disable() to make sure the receiver/transmitter and
interrupts are disabled during the dma steup.

Signed-off-by: Sherry Sun <[email protected]>
---
drivers/tty/serial/fsl_lpuart.c | 13 ++++++++++++-
1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c
index 8918e08bb19e..bb12b328e224 100644
--- a/drivers/tty/serial/fsl_lpuart.c
+++ b/drivers/tty/serial/fsl_lpuart.c
@@ -1682,6 +1682,16 @@ static int lpuart_startup(struct uart_port *port)
return 0;
}

+static void lpuart32_hw_disable(struct lpuart_port *sport)
+{
+ unsigned long temp;
+
+ temp = lpuart32_read(&sport->port, UARTCTRL);
+ temp &= ~(UARTCTRL_RIE | UARTCTRL_ILIE | UARTCTRL_RE |
+ UARTCTRL_TIE | UARTCTRL_TE);
+ lpuart32_write(&sport->port, temp, UARTCTRL);
+}
+
static void lpuart32_configure(struct lpuart_port *sport)
{
unsigned long temp;
@@ -1706,11 +1716,12 @@ static void lpuart32_hw_setup(struct lpuart_port *sport)

spin_lock_irqsave(&sport->port.lock, flags);

- lpuart32_setup_watermark_enable(sport);
+ lpuart32_hw_disable(sport);

lpuart_rx_dma_startup(sport);
lpuart_tx_dma_startup(sport);

+ lpuart32_setup_watermark_enable(sport);
lpuart32_configure(sport);

spin_unlock_irqrestore(&sport->port.lock, flags);
--
2.17.1

2023-01-30 03:02:29

by Sherry Sun

Subject: RE: [PATCH] tty: serial: fsl_lpuart: don't enable receiver/transmitter before rx/tx dma ready

Gentle ping...

Best Regards
Sherry

> -----Original Message-----
> From: Sherry Sun
> Sent: 2022??11??28?? 13:04
> To: [email protected]; [email protected]
> Cc: [email protected]; [email protected]; dl-linux-imx
> <[email protected]>
> Subject: [PATCH] tty: serial: fsl_lpuart: don't enable receiver/transmitter
> before rx/tx dma ready
>
> lpuart32_setup_watermark_enable() will configure the UART FIFO and
> watermark, also enable the receiver and transmitter, this should be done
> after the rx/tx dma steup ready.
>
> Also add lpuart32_hw_disable() to make sure the receiver/transmitter and
> interrupts are disabled during the dma steup.
>
> Signed-off-by: Sherry Sun <[email protected]>
> ---
> drivers/tty/serial/fsl_lpuart.c | 13 ++++++++++++-
> 1 file changed, 12 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c
> index 8918e08bb19e..bb12b328e224 100644
> --- a/drivers/tty/serial/fsl_lpuart.c
> +++ b/drivers/tty/serial/fsl_lpuart.c
> @@ -1682,6 +1682,16 @@ static int lpuart_startup(struct uart_port *port)
> return 0;
> }
>
> +static void lpuart32_hw_disable(struct lpuart_port *sport) {
> + unsigned long temp;
> +
> + temp = lpuart32_read(&sport->port, UARTCTRL);
> + temp &= ~(UARTCTRL_RIE | UARTCTRL_ILIE | UARTCTRL_RE |
> + UARTCTRL_TIE | UARTCTRL_TE);
> + lpuart32_write(&sport->port, temp, UARTCTRL); }
> +
> static void lpuart32_configure(struct lpuart_port *sport) {
> unsigned long temp;
> @@ -1706,11 +1716,12 @@ static void lpuart32_hw_setup(struct
> lpuart_port *sport)
>
> spin_lock_irqsave(&sport->port.lock, flags);
>
> - lpuart32_setup_watermark_enable(sport);
> + lpuart32_hw_disable(sport);
>
> lpuart_rx_dma_startup(sport);
> lpuart_tx_dma_startup(sport);
>
> + lpuart32_setup_watermark_enable(sport);
> lpuart32_configure(sport);
>
> spin_unlock_irqrestore(&sport->port.lock, flags);
> --
> 2.17.1

2023-01-30 05:21:35

by Greg Kroah-Hartman

Subject: Re: [PATCH] tty: serial: fsl_lpuart: don't enable receiver/transmitter before rx/tx dma ready

On Mon, Jan 30, 2023 at 03:02:21AM +0000, Sherry Sun wrote:
> Gentle ping...

This is not in my queue anywhere, sorry, it must have fallen off. Can
you please resend?

thanks,

greg k-h

2023-01-30 05:36:21

by Sherry Sun

Subject: RE: [PATCH] tty: serial: fsl_lpuart: don't enable receiver/transmitter before rx/tx dma ready

> -----Original Message-----
> From: [email protected] <[email protected]>
> Sent: 2023??1??30?? 13:21
> To: Sherry Sun <[email protected]>
> Cc: [email protected]; [email protected]; linux-
> [email protected]; dl-linux-imx <[email protected]>
> Subject: Re: [PATCH] tty: serial: fsl_lpuart: don't enable receiver/transmitter
> before rx/tx dma ready
>
> On Mon, Jan 30, 2023 at 03:02:21AM +0000, Sherry Sun wrote:
> > Gentle ping...
>
> This is not in my queue anywhere, sorry, it must have fallen off. Can you
> please resend?
>

Sure, will resend it, thanks.

Best Regards
Sherry