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why imx6's usdhc hasn't the SDHCI_HOST_VERSION register?

Question asked by senix senix on May 30, 2013
Latest reply on Jun 13, 2013 by senix senix
Branched to a new discussion

in the linux sd driver


#define   SDHCI_SPEC_3002


the linux will read the SDHCI_HOST_VERSION(offset 0xFE), and compare with the SDHCI_SPEC_300:


host->version = sdhci_readw(host, SDHCI_HOST_VERSION);

  host->version = (host->version & SDHCI_SPEC_VER_MASK)


  if (host->version > SDHCI_SPEC_300) {

  printk(KERN_ERR "%s: Unknown controller version (%d). "

  "You may experience problems.\n", mmc_hostname(mmc),




but in the imx6XXXrm.pdf , there isn't the SDHCI_HOST_VERSION register.

so, every boot time ,we'll see the "mmc0: Unknown controller version (3). You may experience problems.."

where is the SDHCI_HOST_VERSION register,what it means?