mci: sdhci: atmel: extend driver for PBL usage ...

The BootROM resets both the SD/MMC host controller and the pin controller,
but the card itself remains in transfer mode. If we redo host-side
setup, we can directly read new blocks off the card.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

mci: sdhci: atmel: use dev_printf instead of pr_print in common code ...

On boards like the sama5d27 som1 ek, we have two SD card slots, so error
messages are more useful if they refer to the SDHCI instance. We didn't
do this at first, because the common code is compiled for PBL as well.
With a sprinkle of preprocessor ifdeffery, we can have both.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

mci: sdhci: atmel: don't print errors on command timeouts ...

Time outs can be expected, e.g. when probing whether a card is a MMC
one. The core handles it, so don't have the driver print an error.

While at it, simplify the error handling. We don't need to read the
status more than once and returning -EPERM on non-timeout is what the
other drivers are doing.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

mci: sdhci: Fix swapped argument for sdhci_write32 ...

sdhci_write32 accepts the register as second argument, not third.
Fix this up.

Fixes: 075179763a ("mci: sdhci: add Atmel SDHCI (sama5d2, sam9x60) support")
Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

mci: sdhci: add Atmel SDHCI (sama5d2, sam9x60) support ...

We already support Ethernet and QSPI on the SAMA5D2, but MMC was so far
missing. Port over the at91bootstrap driver to barebox. Some parts are
based on the U-Boot and Linux implementations.

To support future use in PBL, the driver model and driver implementation
parts are split into separate files with the latter being compilable for PBL
as well.

Registers, which are found in the common Linux sdhci.h have been added
to the barebox sdhci.h. Registers which appear to be Atmel specific have
been added to atmel-sdhci-common.c instead.

The driver still misses some parts, which will follow later:

  - ADMA is unsupported, PIO only for now
  - Only the SD/MMC controller already enabled by the first stage
    bootloader is supported. Further clocking changes appear
    to be necessary to enable another

Both can be retrofitted later on and don't hold us back from booting
from MMC.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>