soc/imgtec/pistachio: Add IMGTEC SPI controller driver

The Serial Peripheral Flash Interface (SPFI) block allows
communication with various devices over the SPI bus.

It uses a configurable transaction interface and it clocks
the bus according to the configured command, address, gap (aka
dummy) and data lengths.

This controller requires the SPI_ATOMIC_SEQUENCING flag set
(write and read done in the same transaction) as it cannot
directly control CS and will assert/de-assert CS at the
beginning/end of a transaction itself.

Note that the size of any transfer cannot be greater than
64KB - 1, as this is configured in a 16-bit field.

The SOC has 2 SPFI interfaces each of them providing 5 slave select
lines. SPFI 0 supports single and dual modes, SPFI 1 supports
single, dual and quad modes.

For SPFI interface 0:
 - The block needs the system PLL and the following top level
   SPI clock registers to be set:
   - CR_cr_top_spi0clkinternal_CTRL[2:0] with division value
   - CR_MIPS_CLOCK_GATE[19]: bit cr_top_SPI0CLKOUT_MIPS set
   - CR_cr_top_SPI0CLKOUT_CTRL[6:0] with division value
 - The following MFIO configuration parameters are also required:
   Signal name		Pad name        MFIO mode
   spim0_d0_txd		MFIO_MIPS_10	0
   spim0_d1_rxd		MFIO_MIPS_9	0
   spim0_mclk		MFIO_MIPS_8	0
   spim0_cs0		MFIO_MIPS_2	1
   spim0_cs1		MFIO_MIPS_1	1
   spim0_cs2		MFIO_MIPS_55	1
			MFIO_MIPS_28	1
   spim0_cs3		MFIO_MIPS_56	1
			MFIO_MIPS_29	1
   spim0_cs4		MFIO_MIPS_57	1
			MFIO_MIMPS_30	1

For SPFI interface 1:
 - The block needs the system PLL and the following top level
   SPI clock registers to be set:
   - CR_cr_top_spi1clkinternal_CTRL[2:0] with division value
   - CR_MIPS_CLOCK_GATE[20]: bit cr_top_SPI1CLKOUT_MIPS set
   - CR_cr_top_SPI1CLKOUT_CTRL[6:0] with division value
 - The following MFIO configuration parameters are also required:
   Signal name		Pad name	MFIO mode
   spim1_d0_txd		MFIO_MIPS_5	0
   spim1_d1_rxd		MFIO_MIPS_4	0
   spim1_mclk		MFIO_MIPS_3	0
   spim1_d2		MFIO_MIPS_6	0
   spim1_d3		MFIO_MIPS_7	0
   spim1_cs0		MFIO_MIPS_0	0
   spim1_cs1		MFIO_MIPS_1	0
   			MFIO_MIPS_58	1
   spim1_cs2		MFIO_MIPS_2	0
   			MFIO_MIPS_55	2
   			MFIO_MIPS_31	1
   spim1_cs3		MFIO_MIPS_56	2
   spim1_cs4		MFIO_MIPS_57	2

BUG=chrome-os-partner:31438, chrome-os-partner:32441
TEST=Tested as bare-metal driver on Pistachio FPGA

Change-Id: I3b3e4475976e6fba58cef93b12d997ec5cb26341
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: 621849942e27f7d6cf2c8ade7f2c4d18d2318b91
Original-Change-Id: Ib257eb6236bd2895281175871b4ab979660f1239
Original-Signed-off-by: Ionela Voinescu <ionela.voinescu@imgtec.com>
Original-Reviewed-on: https://chromium-review.googlesource.com/217320
Original-Reviewed-by: Vadim Bendebury <vbendeb@chromium.org>
Reviewed-on: http://review.coreboot.org/9049
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
5 files changed