[PATCH] arm64: defconfig: Modify number of usable 8250 uart ports

[PATCH] arm64: defconfig: Modify number of usable 8250 uart ports

[Bhavya Kapoor]

Jacinto SoCs have a total of 12 serial uart ports. But only 8 out
of these 12 uarts can be used at a time.

Thus, Modify maximum number of 8250 serial uart ports which can be
supported as well as modify how many 8250 serial uart ports which
we can use in the runtime to 12 for all the SoCs.

Signed-off-by: Bhavya Kapoor <b-kapoor@ti.com>
---
 arch/arm64/configs/defconfig | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/configs/defconfig b/arch/arm64/configs/defconfig
index 57a9abe78ee4..c693736909bc 100644
--- a/arch/arm64/configs/defconfig
+++ b/arch/arm64/configs/defconfig
@@ -454,7 +454,8 @@ CONFIG_SERIO_AMBAKMI=y
 CONFIG_LEGACY_PTY_COUNT=16
 CONFIG_SERIAL_8250=y
 CONFIG_SERIAL_8250_CONSOLE=y
-CONFIG_SERIAL_8250_NR_UARTS=8
+CONFIG_SERIAL_8250_NR_UARTS=12
+CONFIG_SERIAL_8250_RUNTIME_UARTS=12
 CONFIG_SERIAL_8250_EXTENDED=y
 CONFIG_SERIAL_8250_SHARE_IRQ=y
 CONFIG_SERIAL_8250_BCM2835AUX=y
-- 
2.34.1

Re: [PATCH] arm64: defconfig: Modify number of usable 8250 uart ports

[Bhavya Kapoor]

On 16/05/24 3:27 pm, Bhavya Kapoor wrote:
> Jacinto SoCs have a total of 12 serial uart ports. But only 8 out
> of these 12 uarts can be used at a time.
>
> Thus, Modify maximum number of 8250 serial uart ports which can be
> supported as well as modify how many 8250 serial uart ports which
> we can use in the runtime to 12 for all the SoCs.
>
> Signed-off-by: Bhavya Kapoor <b-kapoor@ti.com>
> ---

rebased to next-20240516

>   arch/arm64/configs/defconfig | 3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/arch/arm64/configs/defconfig b/arch/arm64/configs/defconfig
> index 57a9abe78ee4..c693736909bc 100644
> --- a/arch/arm64/configs/defconfig
> +++ b/arch/arm64/configs/defconfig
> @@ -454,7 +454,8 @@ CONFIG_SERIO_AMBAKMI=y
>   CONFIG_LEGACY_PTY_COUNT=16
>   CONFIG_SERIAL_8250=y
>   CONFIG_SERIAL_8250_CONSOLE=y
> -CONFIG_SERIAL_8250_NR_UARTS=8
> +CONFIG_SERIAL_8250_NR_UARTS=12
> +CONFIG_SERIAL_8250_RUNTIME_UARTS=12
>   CONFIG_SERIAL_8250_EXTENDED=y
>   CONFIG_SERIAL_8250_SHARE_IRQ=y
>   CONFIG_SERIAL_8250_BCM2835AUX=y

Re: [PATCH] arm64: defconfig: Modify number of usable 8250 uart ports

[Arnd Bergmann]

On Thu, May 16, 2024, at 09:57, Bhavya Kapoor wrote:
> Jacinto SoCs have a total of 12 serial uart ports. But only 8 out
> of these 12 uarts can be used at a time.
>
> Thus, Modify maximum number of 8250 serial uart ports which can be
> supported as well as modify how many 8250 serial uart ports which
> we can use in the runtime to 12 for all the SoCs.
>
> Signed-off-by: Bhavya Kapoor <b-kapoor@ti.com>

I forget what we had already discussed here. To clarify from my
side: it's ok to raise the limit if there are any known boards that
connect more than 8 8250 style uarts to external devices or
populated connectors.

On the other hand, I don't see any dts file at the moment that
has more than the maximum of 8 in k3-am642-tqma64xxl-mbax4xxl.dts.

If you are adding another board that has more, it helps to
clarify in the patch description that this is indeed a board
requirement, and not just done because the chip has additional
unused uarts.

     Arnd

Re: [PATCH] arm64: defconfig: Modify number of usable 8250 uart ports

[Bhavya Kapoor]

Hi Arnd, our most boards have 6 uarts that can be used in the runtime

but overall our SoC has 12 uarts. And some of our customers have this

requirements that on their custom boards they use more than 8 uarts on their

boards. Thus, we need to enable this to 12 uarts.

Regards

~B-Kapoor

On 17/05/24 12:19 pm, Arnd Bergmann wrote:
> On Thu, May 16, 2024, at 09:57, Bhavya Kapoor wrote:
>> Jacinto SoCs have a total of 12 serial uart ports. But only 8 out
>> of these 12 uarts can be used at a time.
>>
>> Thus, Modify maximum number of 8250 serial uart ports which can be
>> supported as well as modify how many 8250 serial uart ports which
>> we can use in the runtime to 12 for all the SoCs.
>>
>> Signed-off-by: Bhavya Kapoor <b-kapoor@ti.com>
> I forget what we had already discussed here. To clarify from my
> side: it's ok to raise the limit if there are any known boards that
> connect more than 8 8250 style uarts to external devices or
> populated connectors.
>
> On the other hand, I don't see any dts file at the moment that
> has more than the maximum of 8 in k3-am642-tqma64xxl-mbax4xxl.dts.
>
> If you are adding another board that has more, it helps to
> clarify in the patch description that this is indeed a board
> requirement, and not just done because the chip has additional
> unused uarts.
>
>       Arnd

Re: [PATCH] arm64: defconfig: Modify number of usable 8250 uart ports

[Krzysztof Kozlowski]

On 28/05/2024 08:26, Bhavya Kapoor wrote:
> Hi Arnd, our most boards have 6 uarts that can be used in the runtime
> 
> but overall our SoC has 12 uarts. And some of our customers have this
> 
> requirements that on their custom boards they use more than 8 uarts on their
> 
> boards. Thus, we need to enable this to 12 uarts.

defconfig is for boards in tree, for developers, not for customers.
Argument that some out-of-tree user has more uarts does not mean much
for defconfig. If they have some weird hardware, shall we enable it? Or
if they want DEBUG_KOBJECT? Or anything else?

You mistake kernel development defconfig with a distro or product config.

Best regards,
Krzysztof