Re: [U-Boot] [PATCH 3/6] mmc: fsl_esdhc: Add CMD11 support to switch to 1.8V

On Sun, Jun 15, 2014 at 7:46 PM, Otavio Salvador otavio@ossystems.com.br wrote:

This adds support to switch to 1.8V in case CMD11 succeeds.

Signed-off-by: Otavio Salvador otavio@ossystems.com.br

drivers/mmc/fsl_esdhc.c | 30 +++++++++++++++++++++++------- include/fsl_esdhc.h | 2 ++ include/mmc.h | 1 + 3 files changed, 26 insertions(+), 7 deletions(-)

diff --git a/drivers/mmc/fsl_esdhc.c b/drivers/mmc/fsl_esdhc.c index 5541613..c75b38f 100644 --- a/drivers/mmc/fsl_esdhc.c +++ b/drivers/mmc/fsl_esdhc.c @@ -47,19 +47,21 @@ struct fsl_esdhc { uint fevt; /* Force event register */ uint admaes; /* ADMA error status register */ uint adsaddr; /* ADMA system address register */

•   char    reserved2[160]; /* reserved */
  

•   char    reserved2[100]; /* reserved */
  

•   uint    vendorspec;     /* Vendor Specific register */
  

•   char    reserved3[59];  /* reserved */
    uint    hostver;        /* Host controller version register */
  

•   char    reserved3[4];   /* reserved */
  

•   uint    dmaerraddr;     /* DMA error address register */
    char    reserved4[4];   /* reserved */
  

•   uint    dmaerrattr;     /* DMA error attribute register */
  

•   uint    dmaerraddr;     /* DMA error address register */
    char    reserved5[4];   /* reserved */
  

•   uint    dmaerrattr;     /* DMA error attribute register */
  

•   char    reserved6[4];   /* reserved */
    uint    hostcapblt2;    /* Host controller capabilities register 2 */
  

•   char    reserved6[8];   /* reserved */
  

•   char    reserved7[8];   /* reserved */
    uint    tcr;            /* Tuning control register */
  

•   char    reserved7[28];  /* reserved */
  

•   char    reserved8[28];  /* reserved */
    uint    sddirctl;       /* SD direction control register */
  

•   char    reserved8[712]; /* reserved */
  

•   char    reserved9[712]; /* reserved */
    uint    scr;            /* eSDHC control register */
  

};

@@ -334,6 +336,15 @@ esdhc_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd, struct mmc_data *data) goto out; }

•   /* Switch voltage to 1.8V if CMD11 succeeded */
  

•   if (cmd->cmdidx == SD_CMD_SWITCH_UHS18V) {
  

•           esdhc_setbits32(&regs->vendorspec, ESDHC_VENDORSPEC_VSELECT);
  

•           printf("Run CMD11 1.8V switch\n");
  

•           /* Sleep for 5 ms - max time for card to switch to 1.8V */
  

•           udelay(5000);
  

•   }
  

This seems like the wrong place to put this sort of change. send_cmd is meant to deal with sending a command and dealing with any errors. Voltage changes should probably be handled by set_ios. It looks like Linux actually implements a separate op for voltage change, but the operation should be:

send CMD11 deactivate clock change voltage wait 5ms reactivate clock wait 1ms check for errors

Andy