the default partition, eMMC v4.41 and later devices can additionally provide up to: 1 enhanced user data area partition 2 boot partitions 1 RPMB (Replay Protected Memory Block) partition 4 general purpose partitions (optionally with a enhanced or extended attribute) Of these "partitions", only the enhanced user data area one actually slices the user data area partition and, thus, gets handled with the help of geom_flashmap(4). The other types of partitions have address space independent from the default partition and need to be switched to via CMD6 (SWITCH), i. e. constitute a set of additional "disks". The second kind of these "partitions" doesn't fit that well into the design of mmc(4) and mmcsd(4). I've decided to let mmcsd(4) hook all of these "partitions" up as disk(9)'s (except for the RPMB partition as it didn't seem to make much sense to be able to put a file-system there and may require authentication; therefore, RPMB partitions are solely accessible via the newly added IOCTL interface currently; see also below). This approach for one resulted in cleaner code. Second, it retains the notion of mmcsd(4) children corresponding to a single physical device each. With the addition of some layering violations, it also would have been possible for mmc(4) to add separate mmcsd(4) instances with one disk each for all of these "partitions", however. Still, both mmc(4) and mmcsd(4) share some common code now e. g. for issuing CMD6, which has been factored out into mmc_subr.c. Besides simply subdividing eMMC devices, some Intel NUCs having UEFI code in the boot partitions etc., another use case for the partition support is the activation of pseudo-SLC mode, which manufacturers of eMMC chips typically associate with the enhanced user data area and/ or the enhanced attribute of general purpose partitions. CAVEAT EMPTOR: Partitioning eMMC devices is a one-time operation. - Now that properly issuing CMD6 is crucial (so data isn't written to the wrong partition for example), make a step into the direction of correctly handling the timeout for these commands in the MMC layer. Also, do a SEND_STATUS when CMD6 is invoked with an R1B response as recommended by relevant specifications. However, quite some work is left to be done in this regard; all other R1B-type commands done by the MMC layer also should be followed by a SEND_STATUS (CMD13), the erase timeout calculations/handling as documented in specifications are entirely ignored so far, the MMC layer doesn't provide timeouts applicable up to the bridge drivers and at least sdhci(4) currently is hardcoding 1 s as timeout for all command types unconditionally. Let alone already available return codes often not being checked in the MMC layer ... - Add an IOCTL interface to mmcsd(4); this is sufficiently compatible with Linux so that the GNU mmc-utils can be ported to and used with FreeBSD (note that due to the remaining deficiencies outlined above SANITIZE operations issued by/with `mmc` currently most likely will fail). These latter will be added to ports as sysutils/mmc-utils in a bit. Among others, the `mmc` tool of the GNU mmc-utils allows for partitioning eMMC devices (tested working). - For devices following the eMMC specification v4.41 or later, year 0 is 2013 rather than 1997; so correct this for assembling the device ID string properly. - Let mmcsd.ko depend on mmc.ko. Additionally, bump MMC_VERSION as at least for some of the above a matching pair is required. - In the ACPI front-end of sdhci(4) describe the Intel eMMC and SDXC controllers as such in order to match the PCI one. Additionally, in the entry for the 80860F14 SDXC controller remove the eMMC-only SDHCI_QUIRK_INTEL_POWER_UP_RESET. OKed by: imp Submitted by: ian (mmc_switch_status() implementation) |
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bin | ||
cddl | ||
contrib | ||
crypto | ||
etc | ||
gnu | ||
include | ||
kerberos5 | ||
lib | ||
libexec | ||
release | ||
rescue | ||
sbin | ||
secure | ||
share | ||
sys | ||
targets | ||
tests | ||
tools | ||
usr.bin | ||
usr.sbin | ||
.arcconfig | ||
.arclint | ||
COPYRIGHT | ||
LOCKS | ||
MAINTAINERS | ||
Makefile | ||
Makefile.inc1 | ||
Makefile.libcompat | ||
ObsoleteFiles.inc | ||
README | ||
README.md | ||
UPDATING |
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