Hello Erwan,
On 03.02.22 18:10, Erwan Le Ray wrote:
> Add DMA configuration to UART nodes in stm32mp15x (SOC level) and
> remove it at board level to keep current PIO behavior when needed.
> For stm32-ed1 and stm32-dkx boards, UART4 (console) and UART7
> (no HW flow control pin available) are kept in PIO mode, while USART3
> is now configured in DMA mode.
> UART4 (console UART) has to be kept in irq mode, as DMA support for
> console has been removed from the driver by commit e359b4411c28
> ("serial: stm32: fix threaded interrupt handling").
Do I understand correctly that your first patch breaks consoles of
most/all boards, because they will briefly use DMA, which is refused
by the stm32-usart driver and then you add a patch for each board
to fix that breakage?
Such intermittent breakage makes bisection a hassle. /delete-property/
is a no-op when the property doesn't exist, so you could move the first
patch to the very end to avoid intermittent breakage.
I also think that the driver's behavior is a bit harsh. I think it would
be better for the UART driver to print a warning and fall back to
PIO for console instead of outright refusing and rendering the system
silent. That's not mutually exclusive with your patch series here, of course.
Cheers,
Ahmad
>
> For other stm32mp15x-based boards, current configuration is kept for
> all UART instances.
>
> Erwan Le Ray (16):
> ARM: dts: stm32: add DMA configuration to UART nodes on stm32mp151
> ARM: dts: stm32: keep uart4 behavior on stm32mp157c-ed1
> ARM: dts: stm32: keep uart4 and uart7 behavior on stm32mp15xx-dkx
> ARM: dts: stm32: keep uart4 behavior on icore-stm32mp1-ctouch2
> ARM: dts: stm32: keep uart4 behavior on icore-stm32mp1-edimm2.2
> ARM: dts: stm32: keep uart4 behavior on stm32mp157a-iot-box
> ARM: dts: stm32: keep uart nodes behavior on stm32mp1-microdev2.0-of7
> ARM: dts: stm32: keep uart nodes behavior on stm32mp1-microdev2.0
> ARM: dts: stm32: keep uart nodes behavior on stm32mp157a-stinger96
> ARM: dts: stm32: keep uart4 behavior on stm32mp157c-lxa-mc1
> ARM: dts: stm32: keep uart4 behavior on stm32mp157c-odyssey
> ARM: dts: stm32: keep uart nodes behavior on stm32mp15xx-dhcom-drc02
> ARM: dts: stm32: keep uart nodes behavior on stm32mp15xx-dhcom-pdk2
> ARM: dts: stm32: keep uart nodes behavior on stm32mp15xx-dhcom-picoitx
> ARM: dts: stm32: keep uart4 behavior on stm32mp15xx-dhcom-som
> ARM: dts: stm32: keep uart nodes behavior on
> stm32mp15xx-dhcor-avenger96
>
> arch/arm/boot/dts/stm32mp151.dtsi | 21 +++++++++++++++++++
> .../stm32mp157a-icore-stm32mp1-ctouch2.dts | 2 ++
> .../stm32mp157a-icore-stm32mp1-edimm2.2.dts | 2 ++
> arch/arm/boot/dts/stm32mp157a-iot-box.dts | 2 ++
> ...157a-microgea-stm32mp1-microdev2.0-of7.dts | 4 ++++
> ...32mp157a-microgea-stm32mp1-microdev2.0.dts | 4 ++++
> arch/arm/boot/dts/stm32mp157a-stinger96.dtsi | 6 ++++++
> arch/arm/boot/dts/stm32mp157c-ed1.dts | 2 ++
> arch/arm/boot/dts/stm32mp157c-lxa-mc1.dts | 2 ++
> arch/arm/boot/dts/stm32mp157c-odyssey.dts | 2 ++
> .../arm/boot/dts/stm32mp15xx-dhcom-drc02.dtsi | 4 ++++
> arch/arm/boot/dts/stm32mp15xx-dhcom-pdk2.dtsi | 4 ++++
> .../boot/dts/stm32mp15xx-dhcom-picoitx.dtsi | 4 ++++
> arch/arm/boot/dts/stm32mp15xx-dhcom-som.dtsi | 2 ++
> .../boot/dts/stm32mp15xx-dhcor-avenger96.dtsi | 6 ++++++
> arch/arm/boot/dts/stm32mp15xx-dkx.dtsi | 4 ++++
> 16 files changed, 71 insertions(+)
>
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