ARM: Layerscape: don't generate second-stage 2nd.image ...

For layerscape images, barebox currently generates a second stage
barebox that lacks the RCW and PBI and as such can be bootm'd as
any other barebox ARM image. A previous commit implemented bootm
handlers for the RCW and PBI prefixed images and thus the 2nd.image
no longer serves a real purpose. Drop it.

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

ARM: Layerscape: TQMLS1046a: Support booting from QSPI ...

We have to build correct images suitable for QSPI, thus have to call
lspbl_spi_image instead of lspbl_image. In lowlevel code call the
xload function which detects the bootsource rather than hardcoding
SD/MMC.

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

ARM: Layerscape: TQMLS1046a: unify pbi files ...

This unifies the two different pbi files. With our approach for QSPI
booting differences in the pbi files are not necessary:

- We do not do execute in place for QSPI, so we do not need different
  image execution addresses
- Setting up the QSPI clock doesn't hurt even for SD boot

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

ARM: Layerscape: Add QSPI boot support ...

Booting Layerscape from QSPI is a bit tricky and the approach we take is
different from the one U-Boot has taken, so it's worth writing and
reading the following explanation.

The QSPI controller can map the Flash contents into the memory space (On
LS1046a at 0x40000000). The PBL unit uses this to read the RCW from this
memory window. The Layerscape SoCs have a PowerPC history, so it seemed
appropriate for the designers to let the QSPI controller operate in
big endian mode by default. To let the SoC see the correct RCW we have
to write the RCW and PBI data with be64 endianess. Our PBL image tool
pokes the initial binary into the SoC internal SRAM using PBI data as
done with SD/MMC boot aswell. barebox then changes the QSPI controller
endianess to le64 to properly read the barebox binary (placed at an
flash offset of 128KiB, so found in memory at 0x40020000) into SDRAM and
jumps to it.

U-Boot has another approach. Here the initial binary is executed in
place directly at 0x40100000. This means the QSPI controller endianess
must be swapped inside the PBI data. This has the effect that the whole
RCW/PBI data must be 64bit endianess swapped *except* the very last word
of the PBI data which contains the CRC command and is read already with
changed endianess. As a conclusion when porting QSPI PBI files from U-Boot
to barebox skip commands changing the endianess in the QSPI controller
and make sure the image is executed in internal SRAM and not in the
Flash memory window.

Lines like this should be removed:

09550000 000f400c

This sets the binary execution address:

09570604 40100000

For barebox it should be changed to 0x10000000.

As a result the PBI files can probably be unified between SD and QSPI
boot.

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

ARM: Layerscape: TQMLS1046a: Unify SD and eMMC images ...

TQ has unified SD and eMMC images in their U-Boot. Do the same in
barebox aswell.

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

ARM: Layerscape: Add TQ TQMLS1046a board support ...

This adds support for the TQ TQMLS1046a board. Currently supported:

- UART
- SD/MMC
- Network on eth3, eth2 currently not working for unknown reasons

First stage support exists but is currently untested. Serdes ports are
not yet supported.

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

ARM: Layerscape: Add LS1046a RDB board support ...

The RDB is the Freescale LS1046a reference board. This patch adds
support for it. Currently supported:

- DDR4 RAM as read from SPD EEPROM
- UART
- SD/MMC
- RGMII network ports

The Serdes ports are currently not supported.

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

ARM: Add basic Layerscape support ...

This adds basic Layerscape support:

- Makefile/Kconfig
- Register maps
- errata workarounds

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