Am Montag, 19. Januar 2026, 15:05:16 Mitteleuropäische Normalzeit schrieb Alexey Charkov:

On Mon, Jan 19, 2026 at 5:58 PM Quentin Schulz [off-list ref] wrote:

quoted

Hi Alexey,

On 1/19/26 2:43 PM, Alexey Charkov wrote:

quoted

Hi Quentin,

On Mon, Jan 19, 2026 at 3:08 PM Quentin Schulz [off-list ref] wrote:

quoted

Hi Alexey,

On 1/19/26 10:22 AM, Alexey Charkov wrote:

quoted

Rockchip RK3576 UFS controller uses a dedicated pin to reset the connected
UFS device, which can operate either in a hardware controlled mode or as a
GPIO pin.

Power-on default is GPIO mode, but the boot ROM reconfigures it to a
hardware controlled mode if it uses UFS to load the next boot stage.

Given that existing bindings (and rk3576.dtsi) expect a GPIO-controlled
device reset, request the required pin config explicitly.

This doesn't appear to affect Linux, but it does affect U-boot:

Before:
=> md.l 0x2604b398
2604b398: 00000011 00000000 00000000 00000000  ................
< ... snip ... >
=> ufs init
ufshcd-rockchip ufshc@2a2d0000: [RX, TX]: gear=[3, 3], lane[2, 2], pwr[FASTAUTO_MODE, FASTAUTO_MODE], rate = 2
=> md.l 0x2604b398
2604b398: 00000011 00000000 00000000 00000000  ................

After:
=> md.l 0x2604b398
2604b398: 00000011 00000000 00000000 00000000  ................
< ... snip ...>
=> ufs init
ufshcd-rockchip ufshc@2a2d0000: [RX, TX]: gear=[3, 3], lane[2, 2], pwr[FASTAUTO_MODE, FASTAUTO_MODE], rate = 2
=> md.l 0x2604b398
2604b398: 00000010 00000000 00000000 00000000  ................

(0x2604b398 is the respective pin mux register, with its BIT0 driving the
mode of UFS_RST: unset = GPIO, set = hardware controlled UFS_RST)

This helps ensure that GPIO-driven device reset actually fires when the
system requests it, not when whatever black box magic inside the UFSHC
decides to reset the flash chip.

Cc: stable@vger.kernel.org
Fixes: c75e5e010fef ("scsi: arm64: dts: rockchip: Add UFS support for RK3576 SoC")
Reported-by: Quentin Schulz <redacted>
Signed-off-by: Alexey Charkov <alchark@gmail.com>
---
This has originally surfaced during the review of UFS patches for U-boot
at [1], where it was found that the UFS reset line is not requested to be
configured as GPIO but used as such. This leads in some cases to the UFS
driver appearing to control device resets, while in fact it is the
internal controller logic that drives the reset line (perhaps in
unexpected ways).

Thanks Quentin Schulz for spotting this issue.

[1] https://lore.kernel.org/u-boot/259fc358-f72b-4a24-9a71-ad90f2081335@cherry.de/ (local)
---
   arch/arm64/boot/dts/rockchip/rk3576-pinctrl.dtsi | 7 +++++++
   arch/arm64/boot/dts/rockchip/rk3576.dtsi         | 2 +-
   2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/boot/dts/rockchip/rk3576-pinctrl.dtsi b/arch/arm64/boot/dts/rockchip/rk3576-pinctrl.dtsi
index 0b0851a7e4ea..20cfd3393a75 100644
--- a/arch/arm64/boot/dts/rockchip/rk3576-pinctrl.dtsi
+++ b/arch/arm64/boot/dts/rockchip/rk3576-pinctrl.dtsi

@@ -5228,6 +5228,13 @@ ufs_rst: ufs-rst {
                               /* ufs_rstn */
                               <4 RK_PD0 1 &pcfg_pull_none>;
               };
+
+             /omit-if-no-ref/
+             ufs_rst_gpio: ufs-rst-gpio {
+                     rockchip,pins =
+                             /* ufs_rstn */
+                             <4 RK_PD0 RK_FUNC_GPIO &pcfg_pull_none>;

The SoC default is pull-down according to the TRM. Can you check please?
For example, the Rock 4D doesn't seem to have a hardware pull-up or
pull-down on the line and the UFS module only seems to have a debouncer
(capacitor between the line and ground). So except if the chip itself
has a PU/PD, this may be an issue?

The SoC default is indeed pull-down (as stated both in the TRM and in
the reference schematic from RK3576 EVB1). Which I believe means that
the attached device should be held in a reset state until the driver
takes over the control of the GPIO line (which, in turn, is consistent
with the observed behavior when reset handling is not enabled in the
driver but the reset pin is in GPIO mode).

Are you concerned that the chip might unintentionally go in or out of
reset between the moment the pinctrl subsystem claims the pin and the
moment the driver starts outputting a state it desires? This hasn't

Exactly that.

Imagine for some reason the driver EPROBE_DEFER, there can be a lot of
time between the original pinconf/pinmux and the time the GPIO is
actually driven.

At the same time.. I guess it may not matter much if the UFS chip gets
out of reset temporarily as (I assume) when the UFS controller probes
properly, it'll do a full reset of the UFS chip via the reset GPIO.
Don't know anything about UFS, so maybe there could be damage if the UFS
chip gets out of reset if its supplies or IO lines are in an illegal state?

quoted

caused any observable issues in my testing, but I guess we could
explicitly set it to &pcfg_pull_down for more predictable behavior in
line with what's printed on the schematic.

s/schematics/TRM/

I'll let Heiko decide but I would personally go for a PD to match the
default state of the SoC according to the TRM.

Happy to make a v2 with an explicit pull-down. Will wait a bit for any
other potential feedback though.

I'd side with Quentin here, having the pin firmly on one state, when no-one
(board nor driver) is caring would be my preference.
Especially as Quentin said, this is the hardware-default too.

Heiko