Re: [patch v3 2/5] build configuration for AST2500 DMA UART driver

From: Greg KH
Date: Wed Jul 03 2019 - 13:50:35 EST


On Tue, Jun 25, 2019 at 04:14:33PM +0530, sudheer.v wrote:
> From: sudheer veliseti <sudheer.open@xxxxxxxxx>
>
> build config for DMA based UART driver in AST2500.
> Total Available UARTs in AST2500 are 4
>
> Signed-off-by: sudheer veliseti <sudheer.open@xxxxxxxxx>
> ---
>
> Changes in v3:
> - change logs added
>
> drivers/tty/serial/8250/Kconfig | 35 +++++++++++++++++++++++++++++++-
> drivers/tty/serial/8250/Makefile | 1 +
> 2 files changed, 35 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/tty/serial/8250/Kconfig b/drivers/tty/serial/8250/Kconfig
> index 15c2c5463835..c793466a1c47 100644
> --- a/drivers/tty/serial/8250/Kconfig
> +++ b/drivers/tty/serial/8250/Kconfig
> @@ -45,7 +45,7 @@ config SERIAL_8250_DEPRECATED_OPTIONS
> keep the 8250_core.* options around until they revert the changes
> they already did.
>
> - If 8250 is built as a module, this adds 8250_core alias instead.
> + If 8250 is built as a module, this adds 8250_core alias instead.
>
> If you did not notice yet and/or you have userspace from pre-3.7, it
> is safe (and recommended) to say N here.

Why did you change this line?

> @@ -189,6 +189,39 @@ config SERIAL_8250_RUNTIME_UARTS
> with the module parameter "nr_uarts", or boot-time parameter
> 8250.nr_uarts
>
> +config AST_SERIAL_DMA_UART
> + tristate "AST UART driver with DMA"
> + select SERIAL_CORE
> + help
> + UART driver with DMA support for Aspeed BMC AST25XX.
> + this driver supports UARTs in AST2500,AST2600. It uses
> + DMA channel of DMA engines present in these chips.
> + since this dma engine is used only by UARTs it is not
> + added as a separate DMA driver instead added as a layer
> + within UART driver.
> +
> +
> +config AST_NR_DMA_UARTS
> + int "Maximum number of uart dma serial ports"
> + depends on AST_SERIAL_DMA_UART
> + default "4"
> + help
> + Set this to the number of serial ports you want the driver
> + to support. This includes any ports discovered via ACPI or
> + PCI enumeration and any ports that may be added at run-time
> + via hot-plug, or any ISA multi-port serial cards.
> +
> +config AST_RUNTIME_DMA_UARTS
> + int "Number of uart dma serial ports to register at runtime"
> + depends on AST_SERIAL_DMA_UART
> + range 0 AST_NR_DMA_UARTS
> + default "4"
> + help
> + Set this to the maximum number of serial ports you want
> + the kernel to register at boot time. This can be overridden
> + with the module parameter "nr_uarts", or boot-time parameter
> + 8250.nr_uarts

That boot paramter is not correct, right?

Are you sure these all work like you think they work?

thanks,

greg k-h