Re: [PATCH 0/6] mci: rockchip-dwcmshc: add HS200 support

Re: [PATCH 0/6] mci: rockchip-dwcmshc: add HS200 support

[Sascha Hauer]

On 2026-05-07 09:47, Ahmad Fatoum wrote:
> Hi,
> 
> On 5/7/26 9:02 AM, Sascha Hauer wrote:
> > At least on RK3588 the dwcmshc core doesn't have an internal clock
> > divider, we fully rely on the clock tree to configure the MMC clock.
> > By default the clock comes from the 24MHz oscillator. For higher MMC
> > clocks we have to reparent to a PLL clock, but if we do this once the
> > 6bit divider iss not enough to scale down to the 400kHz MMC
> > initialization clock. This means we must dynamically reparent the clock.
> > This series adds support for finding the best divider/mux combination
> > for composite clocks.
> > 
> > This series also adds some fixes to the dwcmshc driver which used to
> > timeout on writing sometimes.
> 
> \o/
> 
> How much faster was the reading now in your testing?

I now reach 120MB/s compared to 20MB/s before.

Sascha

-- 
Pengutronix e.K.                           |                             |
Steuerwalder Str. 21                       | http://www.pengutronix.de/  |
31137 Hildesheim, Germany                  | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |

[PATCH 0/6] mci: rockchip-dwcmshc: add HS200 support

[Sascha Hauer]

At least on RK3588 the dwcmshc core doesn't have an internal clock
divider, we fully rely on the clock tree to configure the MMC clock.
By default the clock comes from the 24MHz oscillator. For higher MMC
clocks we have to reparent to a PLL clock, but if we do this once the
6bit divider iss not enough to scale down to the 400kHz MMC
initialization clock. This means we must dynamically reparent the clock.
This series adds support for finding the best divider/mux combination
for composite clocks.

This series also adds some fixes to the dwcmshc driver which used to
timeout on writing sometimes.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
---
Sascha Hauer (6):
      mci: sdhci: rockchip: set hidspd before re-enabling the clock
      mci: sdhci: rockchip: disable clock while setting DLL
      mci: sdhci: rockchip: Wait for transfer complete interrupt with MMC_RSP_BUSY cmd
      mci: sdhci: rockchip: Update pre-change delay for rockchip platform
      clk: composite: pick best parent for round_rate / set_rate
      mci: sdhci: rockchip: officially support HS200

 drivers/clk/clk-composite.c          | 110 ++++++++++++++++++++++++++++++-----
 drivers/mci/rockchip-dwcmshc-sdhci.c |  51 ++++++++++------
 2 files changed, 128 insertions(+), 33 deletions(-)
---
base-commit: 019d102038a64e6b6e8f445cbfd2d15e68d0ec3f
change-id: 20260507-rockchip-emmc-0e8c5097cf33

Best regards,
-- 
Sascha Hauer <s.hauer@pengutronix.de>

Re: [PATCH 0/6] mci: rockchip-dwcmshc: add HS200 support

[Ahmad Fatoum]

Hi,

On 5/7/26 9:02 AM, Sascha Hauer wrote:
> At least on RK3588 the dwcmshc core doesn't have an internal clock
> divider, we fully rely on the clock tree to configure the MMC clock.
> By default the clock comes from the 24MHz oscillator. For higher MMC
> clocks we have to reparent to a PLL clock, but if we do this once the
> 6bit divider iss not enough to scale down to the 400kHz MMC
> initialization clock. This means we must dynamically reparent the clock.
> This series adds support for finding the best divider/mux combination
> for composite clocks.
> 
> This series also adds some fixes to the dwcmshc driver which used to
> timeout on writing sometimes.

\o/

How much faster was the reading now in your testing?

Cheers,
Ahmad

> 
> Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
> ---
> Sascha Hauer (6):
>       mci: sdhci: rockchip: set hidspd before re-enabling the clock
>       mci: sdhci: rockchip: disable clock while setting DLL
>       mci: sdhci: rockchip: Wait for transfer complete interrupt with MMC_RSP_BUSY cmd
>       mci: sdhci: rockchip: Update pre-change delay for rockchip platform
>       clk: composite: pick best parent for round_rate / set_rate
>       mci: sdhci: rockchip: officially support HS200
> 
>  drivers/clk/clk-composite.c          | 110 ++++++++++++++++++++++++++++++-----
>  drivers/mci/rockchip-dwcmshc-sdhci.c |  51 ++++++++++------
>  2 files changed, 128 insertions(+), 33 deletions(-)
> ---
> base-commit: 019d102038a64e6b6e8f445cbfd2d15e68d0ec3f
> change-id: 20260507-rockchip-emmc-0e8c5097cf33
> 
> Best regards,

-- 
Pengutronix e.K.                  |                             |
Steuerwalder Str. 21              | http://www.pengutronix.de/  |
31137 Hildesheim, Germany         | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686  | Fax:   +49-5121-206917-5555 |