netdev - Re: [PATCH 2/5] arm64: dts: qcom: lemans: Add SDHC controller and SDC pin configuration

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <53aac104-76fb-42b8-9e0d-0e8a3f59b2da@oss.qualcomm.com>
Date: Fri, 5 Sep 2025 14:04:47 +0200
From: Konrad Dybcio <konrad.dybcio@....qualcomm.com>
To: Dmitry Baryshkov <dmitry.baryshkov@....qualcomm.com>
Cc: Wasim Nazir <wasim.nazir@....qualcomm.com>,
        Ulf Hansson <ulf.hansson@...aro.org>, Rob Herring <robh@...nel.org>,
        Krzysztof Kozlowski <krzk+dt@...nel.org>,
        Conor Dooley
 <conor+dt@...nel.org>,
        Bjorn Andersson <andersson@...nel.org>,
        Konrad Dybcio <konradybcio@...nel.org>,
        Richard Cochran <richardcochran@...il.com>, kernel@....qualcomm.com,
        linux-mmc@...r.kernel.org, devicetree@...r.kernel.org,
        linux-kernel@...r.kernel.org, linux-arm-msm@...r.kernel.org,
        netdev@...r.kernel.org, Monish Chunara <quic_mchunara@...cinc.com>
Subject: Re: [PATCH 2/5] arm64: dts: qcom: lemans: Add SDHC controller and SDC
 pin configuration

On 9/5/25 1:45 PM, Dmitry Baryshkov wrote:
> On Fri, Sep 05, 2025 at 01:14:29PM +0200, Konrad Dybcio wrote:
>> On 9/4/25 7:32 PM, Dmitry Baryshkov wrote:
>>> On Thu, Sep 04, 2025 at 04:34:05PM +0200, Konrad Dybcio wrote:
>>>> On 9/4/25 3:35 PM, Dmitry Baryshkov wrote:
>>>>> On Wed, Sep 03, 2025 at 09:58:33PM +0530, Wasim Nazir wrote:
>>>>>> On Wed, Sep 03, 2025 at 06:12:59PM +0200, Konrad Dybcio wrote:
>>>>>>> On 8/27/25 3:20 AM, Dmitry Baryshkov wrote:
>>>>>>>> On Tue, Aug 26, 2025 at 11:51:01PM +0530, Wasim Nazir wrote:
>>>>>>>>> From: Monish Chunara <quic_mchunara@...cinc.com>
>>>>>>>>>
>>>>>>>>> Introduce the SDHC v5 controller node for the Lemans platform.
>>>>>>>>> This controller supports either eMMC or SD-card, but only one
>>>>>>>>> can be active at a time. SD-card is the preferred configuration
>>>>>>>>> on Lemans targets, so describe this controller.
>>>>>>>>>
>>>>>>>>> Define the SDC interface pins including clk, cmd, and data lines
>>>>>>>>> to enable proper communication with the SDHC controller.
>>>>>>>>>
>>>>>>>>> Signed-off-by: Monish Chunara <quic_mchunara@...cinc.com>
>>>>>>>>> Co-developed-by: Wasim Nazir <wasim.nazir@....qualcomm.com>
>>>>>>>>> Signed-off-by: Wasim Nazir <wasim.nazir@....qualcomm.com>
>>>>>>>>> ---
>>>>>>>>>  arch/arm64/boot/dts/qcom/lemans.dtsi | 70 ++++++++++++++++++++++++++++++++++++
>>>>>>>>>  1 file changed, 70 insertions(+)
>>>>>>>>>
>>>>>>>>> diff --git a/arch/arm64/boot/dts/qcom/lemans.dtsi b/arch/arm64/boot/dts/qcom/lemans.dtsi
>>>>>>>>> index 99a566b42ef2..a5a3cdba47f3 100644
>>>>>>>>> --- a/arch/arm64/boot/dts/qcom/lemans.dtsi
>>>>>>>>> +++ b/arch/arm64/boot/dts/qcom/lemans.dtsi
>>>>>>>>> @@ -3834,6 +3834,36 @@ apss_tpdm2_out: endpoint {
>>>>>>>>>  			};
>>>>>>>>>  		};
>>>>>>>>>  
>>>>>>>>> +		sdhc: mmc@...4000 {
>>>>>>>>> +			compatible = "qcom,sa8775p-sdhci", "qcom,sdhci-msm-v5";
>>>>>>>>> +			reg = <0x0 0x087c4000 0x0 0x1000>;
>>>>>>>>> +
>>>>>>>>> +			interrupts = <GIC_SPI 383 IRQ_TYPE_LEVEL_HIGH>,
>>>>>>>>> +				     <GIC_SPI 521 IRQ_TYPE_LEVEL_HIGH>;
>>>>>>>>> +			interrupt-names = "hc_irq", "pwr_irq";
>>>>>>>>> +
>>>>>>>>> +			clocks = <&gcc GCC_SDCC1_AHB_CLK>,
>>>>>>>>> +				 <&gcc GCC_SDCC1_APPS_CLK>;
>>>>>>>>> +			clock-names = "iface", "core";
>>>>>>>>> +
>>>>>>>>> +			interconnects = <&aggre1_noc MASTER_SDC 0 &mc_virt SLAVE_EBI1 0>,
>>>>>>>>> +					<&gem_noc MASTER_APPSS_PROC 0 &config_noc SLAVE_SDC1 0>;
>>>>>>>>> +			interconnect-names = "sdhc-ddr", "cpu-sdhc";
>>>>>>>>> +
>>>>>>>>> +			iommus = <&apps_smmu 0x0 0x0>;
>>>>>>>>> +			dma-coherent;
>>>>>>>>> +
>>>>>>>>> +			resets = <&gcc GCC_SDCC1_BCR>;
>>>>>>>>> +
>>>>>>>>> +			no-sdio;
>>>>>>>>> +			no-mmc;
>>>>>>>>> +			bus-width = <4>;
>>>>>>>>
>>>>>>>> This is the board configuration, it should be defined in the EVK DTS.
>>>>>>>
>>>>>>> Unless the controller is actually incapable of doing non-SDCards
>>>>>>>
>>>>>>> But from the limited information I can find, this one should be able
>>>>>>> to do both
>>>>>>>
>>>>>>
>>>>>> It’s doable, but the bus width differs when this controller is used for
>>>>>> eMMC, which is supported on the Mezz board. So, it’s cleaner to define
>>>>>> only what’s needed for each specific usecase on the board.
>>>>>
>>>>> `git grep no-sdio arch/arm64/boot/dts/qcom/` shows that we have those
>>>>> properties inside the board DT. I don't see a reason to deviate.
>>>>
>>>> Just to make sure we're clear
>>>>
>>>> I want the author to keep bus-width in SoC dt and move the other
>>>> properties to the board dt
>>>
>>> I think bus-width is also a property of the board. In the end, it's a
>>> question of schematics whether we route 1 wire or all 4 wires. git-log
>>> shows that bus-width is being sent in both files (and probalby we should
>>> sort that out).
>>
>> Actually this is the controller capability, so if it can do 8, it should
>> be 8 and the MMC core will do whatever it pleases (the not-super-sure
>> docs that I have say 8 for this platform)
> 
> Isn't it a physical width of the bus between the controller and the slot
> or eMMC chip?

No, that's matched against reported (sd/mmc) card capabilities IIUC

Konrad