Hi Wolfram,
> -----Original Message-----
> From: Biju Das
> Sent: 27 February 2025 16:27
> Subject: RE: [PATCH v3 3/8] mmc: renesas_sdhi: Add support for RZ/G3E SoC
>
> Hi Wolfram,
>
> > -----Original Message-----
> > From: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
> > Sent: 27 February 2025 15:30
> > Subject: RE: [PATCH v3 3/8] mmc: renesas_sdhi: Add support for RZ/G3E
> > SoC
> >
> > Hi Wolfram,
> >
> > Thanks for the feedback.
> >
> > > -----Original Message-----
> > > From: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
> > > Sent: 27 February 2025 15:16
> > > Subject: Re: [PATCH v3 3/8] mmc: renesas_sdhi: Add support for
> > > RZ/G3E SoC
> > >
> > >
> > > > + /*
> > > > + * HW reset might have toggled the regulator state in
> > > > + * HW which regulator core might be unaware of so save
> > > > + * and restore the regulator state during HW reset.
> > > > + */
> > >
> > > Since this is a hard reset, can't we just reset the regulator to an
> > > initial state? It seems strange to preserve a value when the 'preserve' flag is explicitly not
> set.
> >
> > Assume, this happens after the card is switched to UHS state and then
> > the command won't work in UHS state if we bring the regulator initial
> > state of 3.3V ,
> >
> > In external regulator case, we don't toggle the regulator to initial state of 3.3V.
> > That is the reason it is still working even when hard reset is applied in UHS state.
> >
> > Am I missing anything please let me know? I can debug further.
>
> Previously I got an issue, where the card was unable to detect after hot removal and plug.
> Now it is working without this change.
>
> Not sure the previous issue related to delay associated with hard reset.
> I am doing more testing without this change.
I have added some debug code[1], with SDHI1 using internal regulator as it is easy to do insert/removal of SD cards:
Without the regulator register restore code hot removal/plug:
-------------------------------------------------------------
root@smarc-rzg3e:~# [ 31.400277] mmc1: card aaaa removed
[ 31.450751] renesas_sdhi_internal_dmac 15c10000.mmc: #####renesas_sdhi_reset 595 sd_status before reset=10000
[ 31.460812] renesas_sdhi_internal_dmac 15c10000.mmc: #####renesas_sdhi_reset 607 sd_status after reset=1
[ 35.811808] SDHI1-VQMMC: disabling
[ 36.526838] renesas_sdhi_internal_dmac 15c10000.mmc: #####renesas_sdhi_reset 595 sd_status before reset=0
[ 36.536642] renesas_sdhi_internal_dmac 15c10000.mmc: #####renesas_sdhi_reset 607 sd_status after reset=1
[ 39.322682] renesas_sdhi_internal_dmac 15c10000.mmc: #####renesas_sdhi_reset 607 sd_status after reset=1
[ 39.361826] mmc1: Skipping voltage switch
[ 39.610915] mmc1: new high speed SDHC card at address aaaa
[ 39.618237] mmcblk1: mmc1:aaaa SE32G 29.7 GiB
[ 39.629668] mmcblk1: p1
With the regulator register restore code hot removal/plug:
--------------------------------------------------------
root@smarc-rzg3e:~# [ 23.886933] mmc1: card aaaa removed
[ 23.937416] renesas_sdhi_internal_dmac 15c10000.mmc: #####renesas_sdhi_reset 595 sd_status before reset=10000
[ 25.581984] mmc1: new UHS-I speed SDR104 SDHC card at address aaaa
[ 25.589989] mmcblk1: mmc1:aaaa SE32G 29.7 GiB
[ 25.600507] mmcblk1: p1
root@smarc-rzg3e:~#
Please share your thoughts.
[1]
+ dev_err(&host->pdev->dev,"#####%s %d sd_status before reset=%x",__func__,__LINE__, sd_status);
reset_control_reset(priv->rstc);
/* Unknown why but without polling reset status, it will hang */
read_poll_timeout(reset_control_status, ret, ret == 0, 1, 100,
@@ -599,8 +602,13 @@ static void renesas_sdhi_reset(struct tmio_mmc_host *host, bool preserve)
/* At least SDHI_VER_GEN2_SDR50 needs manual release of reset */
sd_ctrl_write16(host, CTL_RESET_SD, 0x0001);
if (priv->rdev)
- sd_ctrl_write32(host, CTL_SD_STATUS, sd_status);
+ sd_ctrl_read32_rep(host, CTL_SD_STATUS, &sd_status, 1);
+
+ dev_err(&host->pdev->dev,"#####%s %d sd_status after reset=%x",__func__,__LINE__, sd_status);
Cheers,
Biju
