RE: Linux v3.1-rc8 : SDHC card do not switch to high speed mode

["Subhash Jadavani" <subhashj@codeaurora.org>]

> -----Original Message-----
> From: linux-mmc-owner@vger.kernel.org [mailto:linux-mmc-
> owner@vger.kernel.org] On Behalf Of Hiremath, Vaibhav
> Sent: Tuesday, October 18, 2011 12:13 AM
> To: Nath, Arindam; Subhash Jadavani; Hebbar, Gururaja; linux-
> mmc@vger.kernel.org
> Cc: linux-omap@vger.kernel.org; prakity@marvell.com;
> prakity@marvell.com; zhangfei.gao@marvell.com; cjb@laptop.org; Saxena,
> Parth
> Subject: RE: Linux v3.1-rc8 : SDHC card do not switch to high speed
> mode
> 
> 
> > -----Original Message-----
> > From: Nath, Arindam [mailto:Arindam.Nath@amd.com]
> > Sent: Monday, October 17, 2011 8:28 PM
> > To: Subhash Jadavani; Hiremath, Vaibhav; Hebbar, Gururaja; linux-
> > mmc@vger.kernel.org
> > Cc: linux-omap@vger.kernel.org; prakity@marvell.com;
> prakity@marvell.com;
> > zhangfei.gao@marvell.com; cjb@laptop.org; Saxena, Parth
> > Subject: RE: Linux v3.1-rc8 : SDHC card do not switch to high speed
> mode
> >
> > +Subhash
> >
> > Hi Subhash,
> >
> > If I am not mistaken, there was patch by you couple of weeks back to
> fix
> > the issue. Did you not post your final version of the patch to
> community?
> >
> [Hiremath, Vaibhav] I could able to trace the patch, but not sure why
> it did not make it to the mainline -
> 
> http://www.mail-archive.com/linux-mmc@vger.kernel.org/msg09358.html
> 
> Fortunately, it is exactly same as what I did.

Arindam,
No, I had not posted the final version of the patch. Chris wanted to use
some macros instead of magic numbers.
One mentioned by Vaibhav
(http://www.mail-archive.com/linux-mmc@vger.kernel.org/msg09358.html) is the
last patch.

Regards,
Subhash

> 
> Thanks,
> Vaibhav
> 
> > Thanks,
> > Arindam
> >
> > > -----Original Message-----
> > > From: Hiremath, Vaibhav [mailto:hvaibhav@ti.com]
> > > Sent: Monday, October 17, 2011 8:19 PM
> > > To: Hebbar, Gururaja; linux-mmc@vger.kernel.org
> > > Cc: linux-omap@vger.kernel.org; Nath, Arindam; prakity@marvell.com;
> > > prakity@marvell.com; zhangfei.gao@marvell.com; cjb@laptop.org;
> Saxena,
> > > Parth
> > > Subject: RE: Linux v3.1-rc8 : SDHC card do not switch to high speed
> > > mode
> > >
> > > > -----Original Message-----
> > > > From: linux-omap-owner@vger.kernel.org [mailto:linux-omap-
> > > > owner@vger.kernel.org] On Behalf Of Hebbar, Gururaja
> > > > Sent: Thursday, October 13, 2011 8:19 PM
> > > > To: linux-mmc@vger.kernel.org
> > > > Cc: linux-omap@vger.kernel.org
> > > > Subject: Linux v3.1-rc8 : SDHC card do not switch to high speed
> mode
> > > >
> > > > Hi all,
> > > >
> > > > We are porting existing OMAP HSMMC driver (omap_hsmmc.c) to an
> > > upcoming
> > > > SOC.
> > > >
> > > > When testing the driver with SanDisk 16GB SDHC Card (SanDisk
> Extreme
> > > HD
> > > > Video 16GB 20Mb/s), we observed that the card doesn't switch to
> High
> > > Speed
> > > > mode.
> > > >
> > > > The card shows that it is compatible with SDA spec3.
> > > >
> > > > We are testing on Linux v3.1-rc8
> > > >
> > > >
> > > > In mmc_sd_init_card(), rocr received from card is 0xc0ff8000,
> (S18A
> > > bit
> > > > not set).
> > > >
> > > > During mmc_sd_setup_card() --> mmc_decode_scr(), when decoding
> scr,
> > > the
> > > > card specifies that it is sda spec3 compatible
> > > >
> > > > 	if (scr->sda_vsn == SCR_SPEC_VER_2)
> > > > 		/* Check if Physical Layer Spec v3.0 is supported */
> > > > 		scr->sda_spec3 = UNSTUFF_BITS(resp, 47, 1);
> > > 	--
> > > > > true
> > > >
> > > > Then during mmc_read_switch(), since it's a sda spec3 card, the
> code
> > > goes
> > > > to read sd3_drv_type & sd3_curr_limit and skips settings
> hs_max_dtr.
> > > >
> > > > mmc_sd_switch_hs() returns back since hs_max_dtr == 0
> > > >
> > > > 	if (card->sw_caps.hs_max_dtr == 0)
> > > > 		return 0;
> > > >
> > > > Because of this Card isn't switched to High Speed mode.
> > > >
> > > [Hiremath, Vaibhav] After doing bisect, I could able to nail down
> the
> > > commit which is leading to this issue.
> > >
> > >
> > > psplinux060:/datalocal/omap-kernel>git bisect good
> > > d6d50a15a2897d4133d536dd4343b5cf21163db3 is the first bad commit
> > > commit d6d50a15a2897d4133d536dd4343b5cf21163db3
> > > Author: Arindam Nath <arindam.nath@amd.com>
> > > Date:   Thu May 5 12:18:59 2011 +0530
> > >
> > >     mmc: sd: add support for driver type selection
> > >
> > >     This patch adds support for setting driver strength during UHS-
> I
> > >     initialization procedure. Since UHS-I cards set S18A (bit 24)
> in
> > >     response to ACMD41, we use this as a base for UHS-I
> initialization.
> > >     We modify the parameter list of mmc_sd_get_cid() so that we can
> > >     save the ROCR from ACMD41 to check whether bit 24 is set.
> > >
> > >     We decide whether the Host Controller supports A, C, or D
> driver
> > >     type depending on the Capabilities register. Driver type B is
> > >     suported by default. We then set the appropriate driver type
> for
> > >     the card using CMD6 mode 1. As per Host Controller spec v3.00,
> we
> > >     set driver type for the host only if Preset Value Enable in the
> > >     Host Control2 register is not set. SDHCI_HOST_CONTROL has been
> > >     renamed to SDHCI_HOST_CONTROL1 to conform to the spec.
> > >
> > >     Tested by Zhangfei Gao with a Toshiba uhs card and general hs
> card,
> > >     on mmp2 in SDMA mode.
> > >
> > >     Signed-off-by: Arindam Nath <arindam.nath@amd.com>
> > >     Reviewed-by: Philip Rakity <prakity@marvell.com>
> > >     Tested-by: Philip Rakity <prakity@marvell.com>
> > >     Acked-by: Zhangfei Gao <zhangfei.gao@marvell.com>
> > >     Signed-off-by: Chris Ball <cjb@laptop.org>
> > >
> > >
> > > I am not a MMC/SD expert, but looking at the logic I did change to
> code
> > > to something like,
> > >
> > >
> > > diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c
> > > index 0370e03..1a45059 100644
> > > --- a/drivers/mmc/core/sd.c
> > > +++ b/drivers/mmc/core/sd.c
> > > @@ -348,10 +348,9 @@ static int mmc_read_switch(struct mmc_card
> *card)
> > >                 }
> > >
> > >                 card->sw_caps.sd3_curr_limit = status[7];
> > > -       } else {
> > > -               if (status[13] & 0x02)
> > > -                       card->sw_caps.hs_max_dtr = 50000000;
> > >         }
> > > +       if (status[13] & 0x02)
> > > +               card->sw_caps.hs_max_dtr = 50000000;
> > >
> > >  out:
> > >         kfree(status);
> > >
> > >
> > > This resolves the issue, and now card is getting detected properly
> as a
> > > high speed card.
> > > May be I am wrong completely here, any pointers? Any comments?
> > >
> > > Thanks,
> > > Vaibhav
> > >
> > > > Is there any solution for this? Has anyone seen this issue.
> > > >
> > > > Thanks in advance.
> > > >
> > > >
> > > > I am also attaching the log I get from the sd dev attr
> > > >
> > > > Regards
> > > > Gururaja
> > > >
> > > > root@arago-
> > > >
> > >
> armv7:/sys/devices/platform/omap/omap_hsmmc.0/mmc_host/mmc0/mmc0:aaaa#
> > > cat
> > > > cid
> > > > 0353445344313647800c03994400ac6f
> > > >
> > > > root@arago-
> > > >
> > >
> armv7:/sys/devices/platform/omap/omap_hsmmc.0/mmc_host/mmc0/mmc0:aaaa#
> > > cat
> > > > csd
> > > > 400e00325b59000076b27f800a404013
> > > >
> > > > root@arago-
> > > >
> > >
> armv7:/sys/devices/platform/omap/omap_hsmmc.0/mmc_host/mmc0/mmc0:aaaa#
> > > cat
> > > > date
> > > > 12/2010
> > > >
> > > > root@arago-
> > > >
> > >
> armv7:/sys/devices/platform/omap/omap_hsmmc.0/mmc_host/mmc0/mmc0:aaaa#
> > > cat
> > > > erase_size
> > > > 512
> > > >
> > > > root@arago-
> > > >
> > >
> armv7:/sys/devices/platform/omap/omap_hsmmc.0/mmc_host/mmc0/mmc0:aaaa#
> > > cat
> > > > fwrev
> > > > 0x0
> > > >
> > > > root@arago-
> > > >
> > >
> armv7:/sys/devices/platform/omap/omap_hsmmc.0/mmc_host/mmc0/mmc0:aaaa#
> > > cat
> > > > hwrev
> > > > 0x8
> > > >
> > > > root@arago-
> > > >
> > >
> armv7:/sys/devices/platform/omap/omap_hsmmc.0/mmc_host/mmc0/mmc0:aaaa#
> > > cat
> > > > name
> > > > SD16G
> > > >
> > > > root@arago-
> > > >
> > >
> armv7:/sys/devices/platform/omap/omap_hsmmc.0/mmc_host/mmc0/mmc0:aaaa#
> > > cat
> > > > manfid
> > > > 0x000003
> > > >
> > > > root@arago-
> > > >
> > >
> armv7:/sys/devices/platform/omap/omap_hsmmc.0/mmc_host/mmc0/mmc0:aaaa#
> > > cat
> > > > oemid
> > > > 0x5344
> > > >
> > > > root@arago-
> > > >
> > >
> armv7:/sys/devices/platform/omap/omap_hsmmc.0/mmc_host/mmc0/mmc0:aaaa#
> > > cat
> > > > preferred_erase_size
> > > > 4194304
> > > >
> > > > root@arago-
> > > >
> > >
> armv7:/sys/devices/platform/omap/omap_hsmmc.0/mmc_host/mmc0/mmc0:aaaa#
> > > cat
> > > > scr
> > > > 0235800000000000
> > > >
> > > > root@arago-
> > > >
> > >
> armv7:/sys/devices/platform/omap/omap_hsmmc.0/mmc_host/mmc0/mmc0:aaaa#
> > > cat
> > > > serial
> > > > 0x0c039944
> > > >
> > > > root@arago-
> > > >
> > >
> armv7:/sys/devices/platform/omap/omap_hsmmc.0/mmc_host/mmc0/mmc0:aaaa#
> > > cat
> > > > type
> > > > SD
> > > >
> > > > root@arago-
> > > >
> > >
> armv7:/sys/devices/platform/omap/omap_hsmmc.0/mmc_host/mmc0/mmc0:aaaa#
> > > cat
> > > > uevent
> > > > DRIVER=mmcblk
> > > > MMC_TYPE=SD
> > > > MMC_NAME=SD16G
> > > > MODALIAS=mmc:block
> > > >
> > > >
> > > > --
> > > > To unsubscribe from this list: send the line "unsubscribe linux-
> omap"
> > > in
> > > > the body of a message to majordomo@vger.kernel.org
> > > > More majordomo info at  http://vger.kernel.org/majordomo-
> info.html
> >
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html