Re: [PATCH v2 8/8] arm64: dts: rockchip: Enable SD-card interface on Radxa E20C

Hi Chukun,

On 2025-03-07 06:52, Yao Zi wrote:

On Fri, Mar 07, 2025 at 11:35:08AM +0800, Chukun Pan wrote:

quoted

Hi,

quoted

+&sdmmc {
+	bus-width = <4>;
+	cap-mmc-highspeed;
+	cap-sd-highspeed;
+	disable-wp;
+	no-sdio;

With 'no-sdio' property:
[  129.608986] mmc_host mmc1: Bus speed (slot 0) = 400000Hz (slot req 400000Hz, actual 400000HZ div = 0)
[  130.711168] mmc1: Card stuck being busy! __mmc_poll_for_busy
[  130.725536] mmc_host mmc1: Bus speed (slot 0) = 300000Hz (slot req 300000Hz, actual 300000HZ div = 0)
[  131.751240] mmc1: Card stuck being busy! __mmc_poll_for_busy
[  131.765608] mmc_host mmc1: Bus speed (slot 0) = 200000Hz (slot req 200000Hz, actual 200000HZ div = 0)
[  132.825083] mmc1: Card stuck being busy! __mmc_poll_for_busy
[  132.839413] mmc_host mmc1: Bus speed (slot 0) = 187500Hz (slot req 187500Hz, actual 187500HZ div = 0)
[  133.960141] mmc1: Card stuck being busy! __mmc_poll_for_busy

Without 'no-sdio' property:
[  105.224019] mmc1: error -22 whilst initialising SDIO card
[  106.290838] mmc1: Card stuck being busy! __mmc_poll_for_busy
[  106.801931] dwmmc_rockchip ffc30000.mmc: Busy; trying anyway
[  107.385835] mmc_host mmc1: Timeou sending command (cmd 0x202000 arg 0x0 status 0x80202000)
[  107.400425] mmc_host mmc1: Bus speed (slot 0) = 300000Hz (slot req 300000Hz, actual 300000HZ div = 0)
[  107.431561] mmc_host mmc1: Bus speed (slot 0) = 49800000Hz (slot req 50000000Hz, actual 49800000HZ div = 0)
[  107.433107] mmc1: new high speed SDIO card at address 0001

So it seems the sdmmc controller actually works with SDIO commands as
well? I don't expect that since the datasheet says RK3528 has only two
SDIO 3.0 controllers.

We could remove the "no-sdio" property if SDIO actually works. Will
apply it in the next version if there's no objection against this.

On the E20C the sdmmc controller is routed to a microSD card slot mainly
intended for use with microSD-cards and should normally not need SDIO.

What card/adapter do you have inserted in the microSD card slot that
requires use of SDIO instead of just SD or MMC? What is the use case you
have that requires removal of no-sdio on E20C?

Regards,
Jonas

Further tests about the capabilities of the controller are welcome.

quoted

# cat /sys/kernel/debug/mmc1/ios
clock:          50000000 Hz
vdd:            21 (3.3 ~ 3.4 V)
bus mode:       2 (push-pull)
chip select:    0 (don't care)
power mode:     2 (on)
bus width:      2 (4 bits)
timing spec:    2 (sd high-speed)
signal voltage: 0 (3.30 V)
driver type:    0 (driver type B)

Thanks,
Chukun

-- 
2.25.1

Best regards,
Yao Zi