u-boot.git/include/mmc.h, branch v2020.01

mmc: add a driver callback for power-cycle

2019-10-10T02:59:48+00:00

Some MMC peripherals require specific power cycle sequence, where some
registers need to be written between the regulator is turned off and then
back on. This is the case for the MMC IP embedded in STM32MP1 SoC.

In STM32MP157 reference manual [1], the power cycle sequence is:
1. Reset the SDMMC with the RCC.SDMMCxRST register bit. This will reset
the SDMMC to the reset state and the CPSM and DPSM to the Idle state.
2. Disable the Vcc power to the card.
3. Set the SDMMC in power-cycle state. This will make that the
SDMMC_D[7:0], SDMMC_CMD and SDMMC_CK are driven low, to prevent the card
from being supplied through the signal lines.
4. After minimum 1ms enable the Vcc power to the card.
5. After the power ramp period set the SDMMC to the power-off state for
minimum 1ms. The SDMMC_D[7:0], SDMMC_CMD and SDMMC_CK are set to
drive “1”.
6. After the 1ms delay set the SDMMC to power-on state in which the
SDMMC_CK clock will be enabled.
7. After 74 SDMMC_CK cycles the first command can be sent to the card.

The step 3. cannot be handled by the current framework implementation.
A new callback (host_power_cycle) is created, and called in
mmc_power_cycle(), after mmc_power_off().

The incorrect power cycle sequence has shown some boot failures on
STM32MP1 with some SD-cards, especially on cold boots when the input
frequency is low (<= 25MHz).
Those failures are no more seen with this correct power cycle sequence.

[1] https://www.st.com/resource/en/reference_manual/DM00327659.pdf

Signed-off-by: Yann Gautier

spl: dm_mmc: Initialize only the required mmc device

2019-10-10T02:59:48+00:00

In SPL, all the available mmc devices gets initialized during boot.
This might not work in cases where clocks are not available for
certain mmc devices(other than boot device) and the support for
enabling device might not be ready.

Texas Instruments' K3 J721E device having a central system controller
(dmsc) is one such example falling in this category. Below is the
sequence for the failing scenario:
- ROM comes up in SD mode and loads SPL by just initialing SD card.
- SPL loads dmsc firmware from SD Card.
Since ROM has enabled SD, SPL need not enable the SD, just need
to re initialize the card. But SPL is trying to initialize other MMC
instances which are in disabled state. Since dmsc firmware is not yet
available, devices cannot be enabled. So in SPL, initialize only the
mmc device that is needed.

Signed-off-by: Lokesh Vutla 
Reviewed-by: Peng Fan

mmc: Rename timeout parameters for clarification

2019-09-05T07:27:31+00:00

It's quite hard to figure out time units for various function that have
timeout parameters. This leads to possible errors when one forgets to
convert ms to us, for example. Let's rename those parameters
correspondingly to 'timeout_us' and 'timeout_ms' to prevent such issues
further.

While at it, add time units info as comments to struct mmc fields.

This commit doesn't change the behavior, only renames parameters names.
Buildman should report no changes at all.

Signed-off-by: Sam Protsenko 
Reviewed-by: Peng Fan 
Reviewed-by: Igor Opaniuk

mmc: support hs400 enhanced strobe mode

2019-07-15T02:30:08+00:00

eMMC 5.1+ supports HS400 Enhances Strobe mode without the need for
tuning procedure.
The flow is as following:
 - set HS_TIMIMG (Highspeed)
 - Host change freq to <= 52Mhz
 - set the bus width to Enhanced strobe and DDR8Bit(CMD6),
   EXT_CSD[183] = 0x86 instead of 0x80
 - set HS_TIMING to 0x3 (HS400)
 - Host change freq to <= 200Mhz
 - Host select HS400 enhanced strobe complete

Signed-off-by: Peng Fan

cmd: Remove mmc_spi command

2019-07-15T02:30:08+00:00

The mmc_spi command was added to manually setup MMC over SPI bus
using command. This was required by the legacy non-DM MMC_SPI driver.

With DM based MMC_SPI driver in-place, we can now use all general
storge commands and mmc command for MMC over SPI bus hence we remove
the mmc_spi command all it's references.

Suggested-by: Bin Meng 
Signed-off-by: Anup Patel 
Reviewed-by: Bin Meng

mmc: When switching partition, use the timeout specified in the ext_csd

2019-07-15T02:16:49+00:00

The e-MMC spec allows the e-MMC to specify a timeout for the partition
switch command. It can take up to 2550 ms. There is no lower limit to this
value in the spec, but do as the the linux driver does and force it to be
at least 300ms.

Signed-off-by: Jean-Jacques Hiblot

mmc: use the generic timeout for cmd6 (SWITCH) provided in the ext_csd

2019-07-15T02:16:49+00:00

Starting with rev 4.5, the eMMC can define a generic timeout for the
SWITCH command.

Following Linux Kernel code, the timeout also changed from 1000 -> 500

Signed-off-by: Jean-Jacques Hiblot

mmc: if possible, poll the busy state using DAT0

2019-07-15T02:16:49+00:00

Using the DAT0 line as a rdy/busy line is an alternative to reading the
status register of the card. It especially useful in situation where the
bus is not in a good shape, like when modes are switched.
This is also how the linux driver behaves.

Note of warning: As per the specification, while polling on DAT0 the CLK
must not turned off: "[...] Without a clock edge the Device (unless
previously disconnected by a deselect command (CMD7)) will force the DAT0
line down, forever. [...]"

Signed-off-by: Jean-Jacques Hiblot

Revert "mmc: Add a new callback function to perform the 74 clocks cycle sequence"

2019-07-15T02:16:49+00:00

This reverts commit 318a7a576bc49aa8b4207e694d3fbd48c663d6ac.

The last and only user of this callback had been the omap_hsmmc driver.
It is not used anymore. Removing the callback.

Signed-off-by: Jean-Jacques Hiblot

mmc: Read sd card detect properties from DT

2019-07-15T02:16:49+00:00

This patch reads card detect properties from device tree &
added mmc capability macros in mmc.h.

Signed-off-by: T Karthik Reddy 
Signed-off-by: Michal Simek