Some Arria10 boards don't have the FPGA programmed externally.
Instead barebox needs to do that. As the Arria10 has the SDRAM
controller in the FPGA, the first thing we need to do is,
configure the FPGA before the SDRAM can even be used.

It works like this:
  1. boot ROM fetches the PBL from MMC
  2. read the MBR from MMC (this depends on the setup done by the boot ROM)
  3. read the Bitstream from the MMC and program the FPGA
  4. re-read the barebox image from MMC, this time with the full barebox
     that is appended to the PBL
  5. jump into the full barebox

Only supported boot device is eMMC.

Signed-off-by: Steffen Trumtrar <s.trumtrar@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Arria10 init code resets all peripherals. Convert this to keep the bootmedium
out of reset and keep the setup done by the boot ROM.

Signed-off-by: Steffen Trumtrar <s.trumtrar@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Arria10 is a SoC + FPGA like the Cyclone5 SoCFPGA that
is already supported in barebox.
Both a the same in some parts, but totaly different in
others. Most of the hardware blocks are the same in the
SoC parts. The OCRAM is larger on the Arria10 and the
SDRAM controller is different.
The serial core only supports 32bit accesses (different to
the 8bit accesses on the Cyclone5).

As Arria10 has 256KB of OCRAM, it is possible to fit a larger
barebox (and/or use PBL) instead of the two stage bootprocess
used on the Cyclone5 and its 64KB OCRAM.

Signed-off-by: Steffen Trumtrar <s.trumtrar@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>