NAME
sdhci —
PCI SD Host Controller bridge
driver
SYNOPSIS
To compile this driver into the kernel, place the following lines in your kernel configuration file:
device mmc
device mmcsd
device sdhciAlternatively, to load the driver as a module at boot time, place the following lines in loader.conf(5):
mmc_load="YES" mmcsd_load="YES" sdhci_load="YES"
DESCRIPTION
Thesdhci driver supports PCI devices with class 8 and
subclass 5 according to SD Host Controller Specification. Driver supports up
to six high speed 4bit MMC/SD slots per controller. Driver attaches mmc bus to
the respective slot on card insertion and detaches it on card removing.
HARDWARE
The sdhci driver supports different
specification compatible chips. The following chips have been verified to
work:
- ENE CB712
- ENE CB714
- RICOH R5C822
- RICOH R5CE823
- TI PCIXX21/XX11/XX12
SEE ALSO
SD Specifications, Part 2, SD Host Controller, Simplified Specification.
AUTHORS
Alexander Motin <mav@FreeBSD.org>
BUGS
Many of existing SD controller chips have some nonstandard requirements, proprietary registers and hardware bugs, requiring additional handling. ENE chips are handled to work fine, while some revisions of RICOH and TI controllers still do not see cards without some additional initialization.