Hi Krzysztof,
On 4/25/25 2:48 AM, Krzysztof Kozlowski wrote:
On Tue, Apr 22, 2025 at 05:05:10PM GMT, Judith Mendez wrote:
Some Microcenter/Patriot SD cards and Kingston eMMC are failing init across Sitara K3 boards. Init failure is due to the sequence when V1P8_SIGNAL_ENA is set. The V1P8_SIGNAL_ENA has a timing component tied to it where if set, switch to full-cycle timing happens. The failing cards do not like change to full-cycle timing before changing bus width, so add flag to sdhci-am654 binding to suppress V1P8_SIGNAL_ENA before changing bus width. The switch to full-cycle timing should happen with HIGH_SPEED_ENA after change of bus width.
Signed-off-by: Judith Mendez jm@ti.com
Documentation/devicetree/bindings/mmc/sdhci-am654.yaml | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/Documentation/devicetree/bindings/mmc/sdhci-am654.yaml b/Documentation/devicetree/bindings/mmc/sdhci-am654.yaml index 676a74695389..0f92bbf8e13b 100644 --- a/Documentation/devicetree/bindings/mmc/sdhci-am654.yaml +++ b/Documentation/devicetree/bindings/mmc/sdhci-am654.yaml @@ -201,6 +201,11 @@ properties: and the controller is required to be forced into Test mode to set the TESTCD bit.
- ti,suppress-v1p8-ena:
Do not tell what the drivers should do, but tell what is the issue with the hardware, e.g. some cards do not like full-cycle.... and this will also hint you that it should be most likely generic, not specific to this device.
Thanks for your review, but this patch has been dropped in v4 since we adopted a new implementation [0] using compatible string.
[0] https://lore.kernel.org/linux-devicetree/20250423180809.l3l6sfbwquaaazar@shr...
~ Judith