Resource: LCE13 Name: eMMC Status and Updates Date: 11-07-2013 Speaker: Ulf Hansson Video: http://youtu.be/K-20aWveaIE

1. (e)MMC status and updates
LCE13, Dublin. 8-12 July 2013
Ulf Hansson

2. Agenda
● Power management
● Generic MMC highlights
● eMMC 4.5 status
● What's is Linaro's future focus?

3. Power Management :1
● Runtime PM for host devices
● Save power in idle by gating clocks, set pinctrls in sleep state
and release references to a power domain.
● Runtime PM for card devices
● To be used for idle power management operations.
● mmc_get|put_card functions.
● Aggressive PM policy, first proof of concept.
● Periodic BKOPS may be implemented.
● Periodic Cache CTRL may be implemented.
● Periodic HS200 re-runting
● Some more?

4. Power Management :2
● Restructure suspend/resume
● Separate suspend for cards and hosts.
● Shutdown support for cards
● Issue suspend commands.

5. Generic MMC highlights
● Card removal logics (slow card removal)
● Signal voltage switch, UHS SD-cards
● .start_signal_voltage_switch - mandatory.
● .card_busy - optional.
● Common MMC DT parser
● Common MMC regulator API
● VCC and VCCQ.

6. eMMC 4.5 status :1
● Sanitize – wipe physical unmapped regions
● An mmc ioctl for 3.11.
● MMC_CAP2_SANITIZE.
● Discard – provide garbage collection information
● MMC_CAP_ERASE.
● Power off notification – gracefully cut power
● For 3.11.
● MMC_CAP2_FULL_PWR_CYCLE needed in suspend,
otherwise we will fall-back to the SLEEP cmd.
● Data tag – mark file system meta data
● MMC_CAP_CMD23 is needed.

7. eMMC 4.5 status :2
● Cache CTRL – flush the internal eMMC cache
● At REQ_FLUSH and at suspend/shutdown.
● MMC_CAP2_CACHE_CTRL.
● Do we need a periodic a flush mechanism?
● HS200 – 200MB bandwidth
● .execute_tuning – mandatory.
● MMC_CAP2_HS200.
● Periodic re-tuning is not supported.
● Move protocol code to core layer.
● Error handling when running in HS200 mode?

8. eMMC 4.5 status :3
● Packed commands – group requests for increased performance
● MMC_CAP2_PACKED_CMD.
● Large page support
● EXT_CSD_DATA_SECTOR_SIZE bit.
● BKOPS (4.41)
● Initial support for BKOPS, acting on level 2/3.
● Period BKOPS not supported yet.
● eMMC 4.51 makes eMMC 4.5 obsolete
● Security extensions.
● Clarifications to the specification.

9. What's is Linaro's future focus
● Periodic/Idle based features
● eMMC 5.x
● Performance optimizations
● Use case profiling database
● F2FS