[PATCH v7 3/3] arm64: dts: ti: k3-j7200: Add support for higher speed modes and update delay select values for MMCSD subsystems
Aswath Govindraju
a-govindraju at ti.com
Tue Mar 23 08:15:37 GMT 2021
Hi Kishon,
On 23/03/21 11:59 am, Kishon Vijay Abraham I wrote:
> Hi Aswath,
>
> On 23/03/21 10:54 am, Aswath Govindraju wrote:
>> Hi Nishanth,
>>
>> On 22/03/21 9:05 pm, Nishanth Menon wrote:
>>> On 18:42-20210322, Aswath Govindraju wrote:
>>>> The following speed modes are now supported in J7200 SoC,
>>>> - HS200 and HS400 modes at 1.8 V card voltage, in MMCSD0 subsystem [1].
>>>> - UHS-I speed modes in MMCSD1 subsystem [1].
>>>>
>>>> Add support for UHS-I modes by adding voltage regulator device tree nodes
>>>> and corresponding pinmux details, to power cycle and voltage switch cards.
>>>> Set respective tags in sdhci0 and remove no-1-8-v tag from sdhci1
>>>> device tree nodes.
>>>>
>>>> Also update the delay values for various speed modes supported, based on
>>>> the revised january 2021 J7200 datasheet[2].
>>>>
>>>> [1] - section 12.3.6.1.1 MMCSD Features, in
>>>> https://www.ti.com/lit/ug/spruiu1a/spruiu1a.pdf,
>>>> (SPRUIU1A – JULY 2020 – REVISED JANUARY 2021)
>>>>
>>>> [2] - https://www.ti.com/lit/ds/symlink/dra821u.pdf,
>>>> (SPRSP57B – APRIL 2020 – REVISED JANUARY 2021)
>>>>
>>>> Signed-off-by: Aswath Govindraju <a-govindraju at ti.com>
>>>> ---
>>>> .../dts/ti/k3-j7200-common-proc-board.dts | 42 +++++++++++++++++++
>>>> arch/arm64/boot/dts/ti/k3-j7200-main.dtsi | 14 ++++++-
>>>> 2 files changed, 54 insertions(+), 2 deletions(-)
>>>>
>>>> diff --git a/arch/arm64/boot/dts/ti/k3-j7200-common-proc-board.dts b/arch/arm64/boot/dts/ti/k3-j7200-common-proc-board.dts
>>>> index b493f939b09a..de8c06bdc825 100644
>>>> --- a/arch/arm64/boot/dts/ti/k3-j7200-common-proc-board.dts
>>>> +++ b/arch/arm64/boot/dts/ti/k3-j7200-common-proc-board.dts
>>>> @@ -16,6 +16,29 @@
>>>> stdout-path = "serial2:115200n8";
>>>> bootargs = "console=ttyS2,115200n8 earlycon=ns16550a,mmio32,0x02800000";
>>>> };
>>>> +
>>>> + vdd_mmc1: fixedregulator-sd {
>>>> + compatible = "regulator-fixed";
>>>> + regulator-name = "vdd_mmc1";
>>>> + regulator-min-microvolt = <3300000>;
>>>> + regulator-max-microvolt = <3300000>;
>>>> + regulator-boot-on;
>>>> + enable-active-high;
>>>> + gpios = <&exp2 2 GPIO_ACTIVE_HIGH>;
>>>
>>> is that gpio ?
>>
>> Yes, that is correct. I'll correct it in the respin
>>
>>> I'd encourage to use vin-supply as well.
>>
>> Will add this in respin.
>>
>>>
>>>> + };
>>>> +
>>>> + vdd_sd_dv: gpio-regulator-vdd-sd-dv {
>>> What does this drive? TLV71033 ?
>>
>> Yes, this node models the TLV71033 voltage regulator that switches the
>> MMC IO signal voltage level between 3.3V and 1.8V.
>
> Nope. Unlike J721e SOM which uses TLV71033 for switching voltage, J7200
> SOM directly uses GPIO input to PMIC to control the output voltage. So
> this should model the gpio input to PMIC.
>
This was the case with older SoMs and on newer ones load switches are
being used[1].
[1] - https://www.ti.com/lit/zip/sprr424, PROC105E6(001)_SCH.pdf, page 24
Thanks,
Aswath
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