Re: [PATCH v2] arm64: dts: ti: k3-am65: Add support for UHS-I modes in MMCSD1 subsystem

From: Aswath Govindraju
Date: Tue May 11 2021 - 05:55:49 EST


On 11/05/21 3:23 pm, Aswath Govindraju wrote:
> UHS-I speed modes are supported in AM65 S.R. 2.0 SoC[1].
>
> Add support by removing the no-1-8-v tag and including the voltage
> regulator device tree nodes for power cycling.
>
> However, the 4 bit interface of AM65 SR 1.0 cannot be supported at 3.3 V or
> 1.8 V because of erratas i2025 and i2026 [2]. As the SD card is the primary
> boot mode for development usecases, continue to enable SD card and disable
> UHS-I modes in it to minimize any ageing issues happening because of
> erratas.
>
> k3-am6528-iot2050-basic and k3-am6548-iot2050-advanced boards use S.R. 1.0
> version of AM65 SoC. Therefore, add no-1-8-v in sdhci1 device tree nodes
> for these boards.
>
> [1] - https://www.ti.com/lit/ug/spruid7e/spruid7e.pdf, section 12.3.6.1.1
> [2] - https://www.ti.com/lit/er/sprz452e/sprz452e.pdf
>
> Signed-off-by: Aswath Govindraju <a-govindraju@xxxxxx>
> ---

changes since v1:
- added no-1-8-v tag in sdhci1 dt nodes of k3-am6528-iot2050-basic and
k3-am6548-iot2050-advanced boards as they use S.R.1.0 version AM65 SoC.

Thanks,
Aswath

> arch/arm64/boot/dts/ti/k3-am65-main.dtsi | 1 -
> .../boot/dts/ti/k3-am6528-iot2050-basic.dts | 4 +++
> .../arm64/boot/dts/ti/k3-am654-base-board.dts | 33 +++++++++++++++++++
> .../dts/ti/k3-am6548-iot2050-advanced.dts | 4 +++
> 4 files changed, 41 insertions(+), 1 deletion(-)
>
> diff --git a/arch/arm64/boot/dts/ti/k3-am65-main.dtsi b/arch/arm64/boot/dts/ti/k3-am65-main.dtsi
> index cb340d1b401f..632f32fce4a1 100644
> --- a/arch/arm64/boot/dts/ti/k3-am65-main.dtsi
> +++ b/arch/arm64/boot/dts/ti/k3-am65-main.dtsi
> @@ -301,7 +301,6 @@
> ti,otap-del-sel = <0x2>;
> ti,trm-icp = <0x8>;
> dma-coherent;
> - no-1-8-v;
> };
>
> scm_conf: scm-conf@100000 {
> diff --git a/arch/arm64/boot/dts/ti/k3-am6528-iot2050-basic.dts b/arch/arm64/boot/dts/ti/k3-am6528-iot2050-basic.dts
> index 4f7e3f2a6265..485266960d5f 100644
> --- a/arch/arm64/boot/dts/ti/k3-am6528-iot2050-basic.dts
> +++ b/arch/arm64/boot/dts/ti/k3-am6528-iot2050-basic.dts
> @@ -40,6 +40,10 @@
> status = "disabled";
> };
>
> +&sdhci1 {
> + no-1-8-v;
> +};
> +
> &main_pmx0 {
> main_uart0_pins_default: main-uart0-pins-default {
> pinctrl-single,pins = <
> diff --git a/arch/arm64/boot/dts/ti/k3-am654-base-board.dts b/arch/arm64/boot/dts/ti/k3-am654-base-board.dts
> index 9e87fb313a54..51c594b4dddb 100644
> --- a/arch/arm64/boot/dts/ti/k3-am654-base-board.dts
> +++ b/arch/arm64/boot/dts/ti/k3-am654-base-board.dts
> @@ -91,6 +91,38 @@
> #clock-cells = <0>;
> clock-frequency = <24000000>;
> };
> +
> + evm_12v0: fixedregulator-evm12v0 {
> + /* main supply */
> + compatible = "regulator-fixed";
> + regulator-name = "evm_12v0";
> + regulator-min-microvolt = <12000000>;
> + regulator-max-microvolt = <12000000>;
> + regulator-always-on;
> + regulator-boot-on;
> + };
> +
> + vcc3v3_io: fixedregulator-vcc3v3io {
> + /* Output of TPS54334 */
> + compatible = "regulator-fixed";
> + regulator-name = "vcc3v3_io";
> + regulator-min-microvolt = <3300000>;
> + regulator-max-microvolt = <3300000>;
> + regulator-always-on;
> + regulator-boot-on;
> + vin-supply = <&evm_12v0>;
> + };
> +
> + vdd_mmc1_sd: fixedregulator-sd {
> + compatible = "regulator-fixed";
> + regulator-name = "vdd_mmc1_sd";
> + regulator-min-microvolt = <3300000>;
> + regulator-max-microvolt = <3300000>;
> + regulator-boot-on;
> + enable-active-high;
> + vin-supply = <&vcc3v3_io>;
> + gpio = <&pca9554 4 GPIO_ACTIVE_HIGH>;
> + };
> };
>
> &wkup_pmx0 {
> @@ -350,6 +382,7 @@
> * disable sdhci1
> */
> &sdhci1 {
> + vmmc-supply = <&vdd_mmc1_sd>;
> pinctrl-names = "default";
> pinctrl-0 = <&main_mmc1_pins_default>;
> ti,driver-strength-ohm = <50>;
> diff --git a/arch/arm64/boot/dts/ti/k3-am6548-iot2050-advanced.dts b/arch/arm64/boot/dts/ti/k3-am6548-iot2050-advanced.dts
> index ec9617c13cdb..3643a19b5f33 100644
> --- a/arch/arm64/boot/dts/ti/k3-am6548-iot2050-advanced.dts
> +++ b/arch/arm64/boot/dts/ti/k3-am6548-iot2050-advanced.dts
> @@ -55,6 +55,10 @@
> disable-wp;
> };
>
> +&sdhci1 {
> + no-1-8-v;
> +};
> +
> &main_uart0 {
> status = "disabled";
> };
>