[PATCH] mmc: fsl_esdhc_imx: use VENDORSPEC_FRC_SDCLK_ON to control card clock output

Bough Chen haibo.chen at nxp.com
Mon Feb 1 11:10:20 CET 2021


> -----Original Message-----
> From: ZHIZHIKIN Andrey [mailto:andrey.zhizhikin at leica-geosystems.com]
> Sent: 2021年2月1日 17:52
> To: Bough Chen <haibo.chen at nxp.com>; Peng Fan <peng.fan at nxp.com>;
> u-boot at lists.denx.de
> Cc: dl-uboot-imx <uboot-imx at nxp.com>; tharvey at gateworks.com
> Subject: RE: [PATCH] mmc: fsl_esdhc_imx: use VENDORSPEC_FRC_SDCLK_ON
> to control card clock output
> 
> Hello Haibo,
> 
> > -----Original Message-----
> > From: haibo.chen at nxp.com <haibo.chen at nxp.com>
> > Sent: Wednesday, January 27, 2021 11:47 AM
> > To: peng.fan at nxp.com; u-boot at lists.denx.de
> > Cc: haibo.chen at nxp.com; uboot-imx at nxp.com; tharvey at gateworks.com;
> > ZHIZHIKIN Andrey <andrey.zhizhikin at leica-geosystems.com>
> > Subject: [PATCH] mmc: fsl_esdhc_imx: use VENDORSPEC_FRC_SDCLK_ON to
> > control card clock output
> >
> > This email is not from Hexagon’s Office 365 instance. Please be
> > careful while clicking links, opening attachments, or replying to this email.
> >
> >
> > From: Haibo Chen <haibo.chen at nxp.com>
> >
> > For FSL_USDHC, it do not implement
> VENDORSPEC_CKEN/PEREN/HCKEN/IPGEN,
> > these are reserved bits. Instead, use VENDORSPEC_FRC_SDCLK_ON to gate
> > on/off the card clock output.
> >
> > After commit b5874b552ffa ("mmc: fsl_esdhc_imx: add wait_dat0()
> > support"), we meet SD3.0 card can't work at UHS mode,
> > mmc_switch_voltage() fail because the second mmc_wait_dat0 return
> > -ETIMEDOUT. According to SD spec, during voltage switch, need to gate
> > off/on the card clock. If not set the FRC_SDCLK_ON, after CMD11,
> > hardware will gate off the card clock automatically, so card do not
> > detect the clock off/on behavior, so will draw the data0 line low until next
> command.
> >
> > Fixes: b5874b552ffa ("mmc: fsl_esdhc_imx: add wait_dat0() support")
> 
> This patch does not fix the switch of uSDHC to 1v8...
> 
> I've applied it locally on the imx8mmevk, and had following log during the boot
> when tried to query SD Card info:
> -----------------------------------------------
> U-Boot SPL 2021.01-01004-gb852007333 (Feb 01 2021 - 09:45:42 +0100)
> Normal Boot
> WDT:   Started with servicing (60s timeout)
> Trying to boot from MMC1
> NOTICE:  BL31: v2.2(release):rel_imx_5.4.70_2.3.0-0-gf1d7187f2
> NOTICE:  BL31: Built : 22:29:05, Jan 17 2021
> 
> 
> U-Boot 2021.01-01004-gb852007333 (Feb 01 2021 - 09:45:42 +0100)
> 
> CPU:   Freescale i.MX8MMQ rev1.0 at 1200 MHz
> Reset cause: POR
> Model: FSL i.MX8MM EVK board
> DRAM:  2 GiB
> WDT:   Started with servicing (60s timeout)
> MMC:   FSL_SDHC: 1, FSL_SDHC: 2
> Loading Environment from MMC... Run CMD11 1.8V switch Card did not
> respond to voltage select! : -110

This do not align with my test result. Can you help identify which function first return the timeout on your side?
Or can you try a different SD card?

Best Regards
Haibo 

> *** Warning - No block device, using default environment
> 
> In:    serial
> Out:   serial
> Err:   serial
> Net:   eth0: ethernet at 30be0000
> Hit any key to stop autoboot:  0
> u-boot=> mmc dev 1
> Card did not respond to voltage select! : -110 u-boot=> mmc info MMC Device
> 0 not found no mmc device at slot 0 u-boot=> mmc dev 2 switch to partitions #0,
> OK mmc2(part 0) is current device u-boot=> mmc info
> Device: FSL_SDHC
> Manufacturer ID: 45
> OEM: 100
> Name: DG401
> Bus Speed: 200000000
> Mode: HS400ES (200MHz)
> Rd Block Len: 512
> MMC version 5.1
> High Capacity: Yes
> Capacity: 14.7 GiB
> Bus Width: 8-bit DDR
> Erase Group Size: 512 KiB
> HC WP Group Size: 8 MiB
> User Capacity: 14.7 GiB WRREL
> Boot Capacity: 4 MiB ENH
> RPMB Capacity: 4 MiB ENH
> Boot area 0 is not write protected
> Boot area 1 is not write protected
> -----------------------------------------------
> 
> Note, that eMMC is not affected and is operating in HS400ES mode without any
> issues.
> 
> Reverting patch b5874b552ffa ("mmc: fsl_esdhc_imx: add wait_dat0() support")
> with this patch applied in tree does switch the SD Card to high-speed mode,
> following log is produced:
> -----------------------------------------------
> U-Boot SPL 2021.01-01005-gb8aeb689a2 (Feb 01 2021 - 10:38:01 +0100)
> Normal Boot
> WDT:   Started with servicing (60s timeout)
> Trying to boot from MMC1
> NOTICE:  BL31: v2.2(release):rel_imx_5.4.70_2.3.0-0-gf1d7187f2
> NOTICE:  BL31: Built : 22:29:05, Jan 17 2021
> 
> 
> U-Boot 2021.01-01005-gb8aeb689a2 (Feb 01 2021 - 10:38:01 +0100)
> 
> CPU:   Freescale i.MX8MMQ rev1.0 at 1200 MHz
> Reset cause: POR
> Model: FSL i.MX8MM EVK board
> DRAM:  2 GiB
> WDT:   Started with servicing (60s timeout)
> MMC:   FSL_SDHC: 1, FSL_SDHC: 2
> Loading Environment from MMC... Run CMD11 1.8V switch
> *** Warning - bad CRC, using default environment
> 
> In:    serial
> Out:   serial
> Err:   serial
> Net:   eth0: ethernet at 30be0000
> Hit any key to stop autoboot:  0
> u-boot=> mmc dev 1
> Run CMD11 1.8V switch
> switch to partitions #0, OK
> mmc1 is current device
> u-boot=> mmc info
> Device: FSL_SDHC
> Manufacturer ID: 41
> OEM: 3432
> Name: SD32G
> Bus Speed: 200000000
> Mode: UHS SDR104 (208MHz)
> Rd Block Len: 512
> SD version 3.0
> High Capacity: Yes
> Capacity: 29.3 GiB
> Bus Width: 4-bit
> Erase Group Size: 512 Bytes
> u-boot=> mmc dev 2
> switch to partitions #0, OK
> mmc2(part 0) is current device
> u-boot=> mmc info
> Device: FSL_SDHC
> Manufacturer ID: 45
> OEM: 100
> Name: DG401
> Bus Speed: 200000000
> Mode: HS400ES (200MHz)
> Rd Block Len: 512
> MMC version 5.1
> High Capacity: Yes
> Capacity: 14.7 GiB
> Bus Width: 8-bit DDR
> Erase Group Size: 512 KiB
> HC WP Group Size: 8 MiB
> User Capacity: 14.7 GiB WRREL
> Boot Capacity: 4 MiB ENH
> RPMB Capacity: 4 MiB ENH
> Boot area 0 is not write protected
> Boot area 1 is not write protected
> -----------------------------------------------
> 
> I guess high-level modifications are also required, since the uSDHC does not
> follow the SD Specification in regards to voltage switching, which is currently
> implemented in U-Boot, this patch alone does not solve the mode switch.
> 
> > Signed-off-by: Haibo Chen <haibo.chen at nxp.com>
> > ---
> >  drivers/mmc/fsl_esdhc_imx.c | 29 +++++++++++++++++++++--------
> >  include/fsl_esdhc_imx.h     |  2 ++
> >  2 files changed, 23 insertions(+), 8 deletions(-)
> >
> > diff --git a/drivers/mmc/fsl_esdhc_imx.c b/drivers/mmc/fsl_esdhc_imx.c
> > index
> > 8ac859797f..da33ee8253 100644
> > --- a/drivers/mmc/fsl_esdhc_imx.c
> > +++ b/drivers/mmc/fsl_esdhc_imx.c
> > @@ -653,7 +653,10 @@ static void set_sysctl(struct fsl_esdhc_priv
> > *priv, struct mmc *mmc, uint clock)
> >         clk = (pre_div << 8) | (div << 4);
> >
> >  #ifdef CONFIG_FSL_USDHC
> > -       esdhc_clrbits32(&regs->vendorspec, VENDORSPEC_CKEN);
> > +       esdhc_clrbits32(&regs->vendorspec,
> VENDORSPEC_FRC_SDCLK_ON);
> > +       ret = readx_poll_timeout(esdhc_read32, &regs->prsstat, tmp,
> > + tmp &
> > PRSSTAT_SDOFF, 100);
> > +       if (ret)
> > +               pr_warn("fsl_esdhc_imx: Internal clock never gate
> > + off.\n");
> >  #else
> >         esdhc_clrbits32(&regs->sysctl, SYSCTL_CKEN);  #endif @@
> -665,7
> > +668,7 @@ static void set_sysctl(struct fsl_esdhc_priv *priv, struct mmc
> *mmc, uint clock)
> >                 pr_warn("fsl_esdhc_imx: Internal clock never
> > stabilised.\n");
> >
> >  #ifdef CONFIG_FSL_USDHC
> > -       esdhc_setbits32(&regs->vendorspec, VENDORSPEC_PEREN |
> > VENDORSPEC_CKEN);
> > +       esdhc_setbits32(&regs->vendorspec,
> VENDORSPEC_FRC_SDCLK_ON);
> >  #else
> >         esdhc_setbits32(&regs->sysctl, SYSCTL_PEREN | SYSCTL_CKEN);
> > #endif @@ -
> > 720,8 +723,14 @@ static void esdhc_set_strobe_dll(struct mmc *mmc)
> >         struct fsl_esdhc_priv *priv = dev_get_priv(mmc->dev);
> >         struct fsl_esdhc *regs = priv->esdhc_regs;
> >         u32 val;
> > +       u32 tmp;
> > +       int ret;
> >
> >         if (priv->clock > ESDHC_STROBE_DLL_CLK_FREQ) {
> > +               esdhc_clrbits32(&regs->vendorspec,
> VENDORSPEC_FRC_SDCLK_ON);
> > +               ret = readx_poll_timeout(esdhc_read32, &regs->prsstat,
> > + tmp, tmp &
> > PRSSTAT_SDOFF, 100);
> > +               if (ret)
> > +                       pr_warn("fsl_esdhc_imx: Internal clock never
> > + gate off.\n");
> >                 esdhc_write32(&regs->strobe_dllctrl,
> > ESDHC_STROBE_DLL_CTRL_RESET);
> >
> >                 /*
> > @@ -739,6 +748,7 @@ static void esdhc_set_strobe_dll(struct mmc *mmc)
> >                         pr_warn("HS400 strobe DLL status REF not
> lock!\n");
> >                 if (!(val & ESDHC_STROBE_DLL_STS_SLV_LOCK))
> >                         pr_warn("HS400 strobe DLL status SLV not
> > lock!\n");
> > +               esdhc_setbits32(&regs->vendorspec,
> > + VENDORSPEC_FRC_SDCLK_ON);
> >         }
> >  }
> >
> > @@ -962,14 +972,18 @@ static int esdhc_set_ios_common(struct
> > fsl_esdhc_priv *priv, struct mmc *mmc)  #ifdef MMC_SUPPORTS_TUNING
> >         if (mmc->clk_disable) {
> >  #ifdef CONFIG_FSL_USDHC
> > -               esdhc_clrbits32(&regs->vendorspec,
> VENDORSPEC_CKEN);
> > +               u32 tmp;
> > +
> > +               esdhc_clrbits32(&regs->vendorspec,
> VENDORSPEC_FRC_SDCLK_ON);
> > +               ret = readx_poll_timeout(esdhc_read32, &regs->prsstat,
> > + tmp, tmp &
> > PRSSTAT_SDOFF, 100);
> > +               if (ret)
> > +                       pr_warn("fsl_esdhc_imx: Internal clock never
> > + gate off.\n");
> >  #else
> >                 esdhc_clrbits32(&regs->sysctl, SYSCTL_CKEN);  #endif
> >         } else {
> >  #ifdef CONFIG_FSL_USDHC
> > -               esdhc_setbits32(&regs->vendorspec,
> VENDORSPEC_PEREN |
> > -                               VENDORSPEC_CKEN);
> > +               esdhc_setbits32(&regs->vendorspec,
> > + VENDORSPEC_FRC_SDCLK_ON);
> >  #else
> >                 esdhc_setbits32(&regs->sysctl, SYSCTL_PEREN |
> > SYSCTL_CKEN);  #endif @@ -1045,7 +1059,7 @@ static int
> > esdhc_init_common(struct fsl_esdhc_priv *priv, struct mmc *mmc)  #ifndef
> CONFIG_FSL_USDHC
> >         esdhc_setbits32(&regs->sysctl, SYSCTL_HCKEN | SYSCTL_IPGEN);
> #else
> > -       esdhc_setbits32(&regs->vendorspec, VENDORSPEC_HCKEN |
> > VENDORSPEC_IPGEN);
> > +       esdhc_setbits32(&regs->vendorspec,
> VENDORSPEC_FRC_SDCLK_ON);
> >  #endif
> >
> >         /* Set the initial clock speed */ @@ -1183,8 +1197,7 @@ static
> > int fsl_esdhc_init(struct fsl_esdhc_priv *priv,
> >         esdhc_write32(&regs->autoc12err, 0);
> >         esdhc_write32(&regs->clktunectrlstatus, 0);  #else
> > -       esdhc_setbits32(&regs->vendorspec, VENDORSPEC_PEREN |
> > -                       VENDORSPEC_HCKEN | VENDORSPEC_IPGEN |
> VENDORSPEC_CKEN);
> > +       esdhc_setbits32(&regs->vendorspec,
> VENDORSPEC_FRC_SDCLK_ON);
> >  #endif
> >
> >         if (priv->vs18_enable)
> > diff --git a/include/fsl_esdhc_imx.h b/include/fsl_esdhc_imx.h index
> > 45ed635a77..b092034464 100644
> > --- a/include/fsl_esdhc_imx.h
> > +++ b/include/fsl_esdhc_imx.h
> > @@ -39,6 +39,7 @@
> >  #define VENDORSPEC_HCKEN       0x00001000
> >  #define VENDORSPEC_IPGEN       0x00000800
> >  #define VENDORSPEC_INIT                0x20007809
> > +#define VENDORSPEC_FRC_SDCLK_ON 0x00000100
> >
> >  #define IRQSTAT                        0x0002e030
> >  #define IRQSTAT_DMAE           (0x10000000)
> > @@ -96,6 +97,7 @@
> >  #define PRSSTAT_CINS           (0x00010000)
> >  #define PRSSTAT_BREN           (0x00000800)
> >  #define PRSSTAT_BWEN           (0x00000400)
> > +#define PRSSTAT_SDOFF          (0x00000080)
> >  #define PRSSTAT_SDSTB          (0X00000008)
> >  #define PRSSTAT_DLA            (0x00000004)
> >  #define PRSSTAT_CICHB          (0x00000002)
> > --
> > 2.17.1



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