The at91sam9m10g45 also support WDRBT bit, add support for it
Signed-off-by: Bo Shen <voice.shen@atmel.com>
Signed-off-by: Andreas Bießmann <andreas.devel@googlemail.com>
Measuring the spi clock line on a scope shows a 'glitch' during the reset of the
spi.
Fix this by toggling only the MXC_CSPICTRL_EN bit, so that the clock line becomes
always stable.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Acked-by: Stefano Babic <sbabic@denx.de>
In decode_cs() function the polarity of the chip select must be taken into
account.
Also, for the case of low active chip select, the CS was activated too early.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
This patch adds SPI driver for EXYNOS.
Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Padmavathi Venna <padma.v@samsung.com>
Signed-off-by: Gabe Black <gabeblack@google.com>
Signed-off-by: Rajeshwari Shinde <rajeshwari.s@samsung.com>
Signed-off-by: Hatim Ali <hatim.rv@samsung.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Acked-by: Simon Glass <sjg@chromium.org>
Tested-by: jy0922.shim@samsung.com
Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
D0/D1 Swapped or not is a board property, not anything specific to
the am33xx SoC, so add a custom define for it.
At the same time correct the bit handling for the swapped mode
(DPE0 should be cleared and SI/DPE1 set).
Signed-off-by: Peter Korsgaard <peter.korsgaard@barco.com>
Current espi controller driver assumes the command length of write command is
not equal to '1', it was made based on SPANSION SPI flash, but some SPI flash
driver such as SST does use write command length as '1', so write command on
SST SPI flash will not work. And the length check for write command is not
necessary for SPANSION, though it's harmless for SPANSION, it will stop write
operation on flashes like SST, so we remove the check.
Signed-off-by: Shaohui Xie <Shaohui.Xie@freescale.com>
Signed-off-by: Andy Fleming <afleming@freescale.com>
The move is pretty straight-forward. ap20.h and tegra20.h were renamed to ap.h and tegra.h.
Some files remain in arch-tegra20 but 'include' a file in 'arch-tegra' with #defines & structs
that will be common between T20 and T30 HW. HW-specific #defines, etc. stay in the 'arch-tegra20'
'root' file.
All boards build OK w/MAKEALL -s tegra20. Checkpatch.pl runs clean. Seaboard works OK.
Signed-off-by: Tom Warren <twarren@nvidia.com>
This patch adds a driver for Freescale Colfire Queued SPI bus.
Coded to work with 8 bits per transfer to use with SPI flash.
CPOL, CPHA, and CS_ACTIVE_HIGH can be configured.
Tested with MCF5270 which have 4 chip selects.
Activate by #define CONFIG_CF_QSPI in board config.
Signed-off-by: Richard Retanubun <richardretanubun@ruggedcom.com>
The MPC8308RDB Reference Manual states that no bits in the SPMODE
register are allowed to change while the enable (EN) bit is set.
This driver changes the character length bits (LEN) while the enable
(EN) bit is set. Clearing the EN bit while changing the LEN bits makes
the driver work correctly on MPC8308RDB.
Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
Warning is:
xilinx_spi.c: In function 'spi_setup_slave':
xilinx_spi.c:81: warning: unused variable 'regs'
Signed-off-by: Stephan Linz <linz@li-pro.net>
CC: Michal Simek <monstr@monstr.eu>
Convert TEGRA20_ defines to either TEGRA_ or NV_PA_ where appropriate.
Convert tegra20_ source file and function names to tegra_, also.
Upcoming Tegra30 port will use common code/defines/names where possible.
Signed-off-by: Tom Warren <twarren@nvidia.com>
Acked-by: Stephen Warren <swarren@nvidia.com>
It turns out that in order for the SPI DMA to properly support
continuous transfers longer than 65280 bytes, there are some very
important parts that were left out from the documentation.
Firstly, the XFER_SIZE register is not written with the whole length
of a transfer, but is written by each and every chained descriptor
with the length of the descriptors data buffer.
Next, unlike the demo code supplied by FSL, which only writes one PIO
word per descriptor, this does not apply if the descriptors are chained,
since the XFER_SIZE register must be written. Therefore, it is essential
to use four PIO words, CTRL0, CMD0, CMD1, XFER_SIZE. CMD0 and CMD1 are
written with zero, since they don't apply. The DMA programs the PIO words
in an incrementing order, so four PIO words.
Finally, unlike the demo code supplied by FSL, the SSP_CTRL0_IGNORE_CRC
must not be set during the whole transfer, but it must be set only on the
last descriptor in the chain.
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: Otavio Salvador <otavio@ossystems.com.br>
Cc: Stefano Babic <sbabic@denx.de>
This patch fixes dcache-related problem. The problem manifested
when dcache was enabled and the following command issued twice:
mw 0x42000000 0 0x4000 ; sf probe ; sf read 0x42000000 0x0 0x10000 ; sha1sum 0x42000000 0x10000
The SHA1 checksum was correct during the first call. Yet with
every subsequent call of the above command, it differed and was
wrong.
It turns out this was because of a race condition. On the first
time the command was called, no cacheline contained any data from
the destination memory location. The DMA transfered data into the
location and the cache above the location was invalidated. Then the
checksum was computed, but that meant the data were loaded into data
cache.
On any subsequent call, the DMA again transfered data into the same
destination. Yet during the transfer, some of the DCache lines were
evicted and written back into the main memory. Once the DMA transfer
completed, the data cache was invalidated over the memory location as
usual. But the data that were to be loaded back into the data cache
by subsequent SHA1 checksuming were corrupted.
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: Otavio Salvador <otavio@ossystems.com.br>
Cc: Stefano Babic <sbabic@denx.de>
The computation was not correct with low clock values: setting a 1MHz
clock would result in an overlap that would then configure a 25Mhz
clock.
This patch implements a correct computation method according to the
kirkwood functionnal spec. table 600 (Serial Memory Interface
Configuration Register).
Signed-off-by: Valentin Longchamp <valentin.longchamp@keymile.com>
cc: Holger Brunck <holger.brunck@keymile.com>
cc: Prafulla Wadaskar <prafulla@marvell.com>
Acked-by: Prafulla Wadaskar <Prafulla@marvell.com>
Signed-off-by: Prafulla Wadaskar <prafulla@marvell.com>
The atmel at91sam9x5 series spi has feature to avoid receive overren
Using the patch to enable it
Signed-off-by: Bo Shen <voice.shen@atmel.com>
Acked-by: Andreas Bießmann <andreas.devel@googlemail.com>
Signed-off-by: Andreas Bießmann <andreas.devel@googlemail.com>
This change implements DMA chaining into SPI driver. This allows
the transfers to go much faster, while also fixing SF issues.
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: Otavio Salvador <otavio@ossystems.com.br>
Cc: Stefano Babic <sbabic@denx.de>
Use calloc() instead of malloc() to allocate the mxs_spi_slave structure.
Clearing the memory is necessary since most of the time this gets done
super early in boot, but on warm reboots, and when SPI probing is done
long after the init stages it could actually pick up previously used memory,
and things like the chipselect polarity and other data end up being filled
with trash data if not explicitly set by the board files.
This solves a semi-random, almost unreproducable error whereby SPI devices
act very, very strangly on boot.
Signed-off-by: Matt Sealey <matt@genesi-usa.com>
Acked-by: Stefano Babic <sbabic@denx.de>
Use calloc() instead of malloc() to allocate the mxc_spi_slave structure.
Clearing the memory is necessary since most of the time this gets done
super early in boot, but on warm reboots, and when SPI probing is done
long after the init stages it could actually pick up previously used memory,
and things like the chipselect polarity and other data end up being filled
with trash data if not explicitly set by the board files.
This solves a semi-random, almost unreproducable error whereby SPI devices
act very, very strangly on boot. Tested on Efika MX over several years..
Signed-off-by: Matt Sealey <matt@genesi-usa.com>
Acked-by: Stefano Babic <sbabic@denx.de>
Since the input frequency of the API is a maximum that should not be exceeded in
order for the devices to operate properly, the SPI clock divider should be
rounded up, not truncated.
Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
Cc: Wolfgang Denk <wd@denx.de>
Cc: Stefano Babic <sbabic@denx.de>
Acked-by: Stefano Babic <sbabic@denx.de>
The sys_proto.h functions (except the boot modes) are compatible with
i.MX233 and i.MX28 so we use 'mxs' prefix for its methods.
Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
This is make naming consistent with the kernel and devicetree and in
preparation of pulling out the common tegra20 code.
Signed-off-by: Allen Martin <amartin@nvidia.com>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Tested-by: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Tom Warren <twarren@nvidia.com>
The DMA transfers happen only if the transfered data are larger
than 512 bytes. Otherwise PIO is used. This is a small speed
optimization.
The DMA transfer doesn't work if unaligned transfer is requested
due to the limitation of the DMA controller. This has to be fixed
by introducing generic bounce buffer. Therefore the DMA feature
is now disabled by default.
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: Otavio Salvador <otavio@ossystems.com.br>
Cc: Stefano Babic <sbabic@denx.de>
Cc: Wolfgang Denk <wd@denx.de>
Pull out all the PIO transfer logic into separate function,
so DMA can be added.
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: Otavio Salvador <otavio@ossystems.com.br>
Cc: Stefano Babic <sbabic@denx.de>
Cc: Wolfgang Denk <wd@denx.de>
This makes it easier to adapt for addition of DMA support.
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: Otavio Salvador <otavio@ossystems.com.br>
Cc: Stefano Babic <sbabic@denx.de>
Cc: Wolfgang Denk <wd@denx.de>
The patch "spi: tegra2: rename tegra2_spi.* to tegra_spi.*"
(sha1: edffa63d3d)
renamed tegra2_spi.c to tegra_spi.c
and the patch "Merge branch 'master' of git://git.denx.de/u-boot-microblaze"
(sha1: d978780b2e)
has wrongly resolved confict.
This patch fix it.
Signed-off-by: Michal Simek <monstr@monstr.eu>
* 'master' of git://git.denx.de/u-boot-microblaze:
microblaze: Wire up SPI driver
spi: microblaze: Adds driver for Xilinx SPI controller
microblaze: intc: Clear interrupt code
microblaze: Call serial multi initialization
microblaze: Move __udelay implementation
microblaze: Remove extern from board.c
microblaze: Wire up dts configuration
fdt: Add board specific dts inclusion
microblaze: Move individual board linker scripts to common script in cpu tree.
microblaze: Add gpio.h
microblaze: Add missing undefs for UBI and UBIFS
microblaze: Expand and correct configuration comments
microblaze: Enable ubi support
microblaze: Avoid compile error on systems without cfi flash
microblaze: Remove wrong define CONFIG_SYS_FLASH_PROTECTION
Conflicts:
drivers/spi/Makefile
Signed-off-by: Wolfgang Denk <wd@denx.de>
This is an improved version of the driver patch original
submitted by Graeme Smecher <graeme.smecher@mail.mcgill.ca>
The changes are:
- remove hard coded Xilinx BSP defines (XPAR_SPI_*) and
use CONFIG_SYS_SPI_BASE from config.h instead
- add extensive register struct definitions
- remove offset calculation for register access and
use the new register struct instead
- move default SPI controller configuration from
spi_setup_slave() to spi_claim_bus()
- add spi_set_speed()
- insert SPI controller deactivation in spi_release_bus()
- protect while loops in spi_xfer() with counter / timeouts
- support SPI mode flags: LSB_FIRST, CPHA, CPOL, LOOP
Come from:
http://patchwork.ozlabs.org/patch/71797/
Signed-off-by: Stephan Linz <linz@li-pro.net>
Tested-by: Michal Simek <monstr@monstr.eu>
MXS SSP controller may have up to three chip selects per port: SS0, SS1 and SS2.
Currently only SS0 is supported in the mxs_spi driver.
Allow all the three chip select to work by selecting the desired one
in bits 20 and 21 of the HW_SSP_CTRL0 register.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Acked-by: Marek Vasut <marex@denx.de>
Introduce spi_cs_is_valid() for validating spi bus and chip select numbers.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Acked-by: Marek Vasut <marex@denx.de>
Acked-by: Mike Frysinger <vapier@gentoo.org>
* 'master' of git://git.denx.de/u-boot-arm: (146 commits)
arm: Use common .lds file where possible
arm: add a common .lds link script
arm: Remove unneeded setting of LDCSRIPT
Define CPUDIR for the .lds link script
arm: Remove zipitz2 link script
Allow arch directory to contain .lds without requiring Makefile
OMAP: Remove omap1610inn-based boards
arch/arm/cpu/armv7/omap-common/clocks-common.c: Fix build warnings
board/ti/beagle/beagle.c: Fix build warnings
sdrc.c: Fix typo in do_sdrc_init() for SPL
tegra: i2c: Add I2C driver
tegra: fdt: i2c: Add extra I2C bindings for U-Boot
tegra: i2c: Select I2C ordering for Seaboard
tegra: i2c: Enable I2C on Seaboard
tegra: i2c: Select number of controllers for Tegra2 boards
tegra: i2c: Initialise I2C on Nvidia boards
tegra: Enhance clock support to handle 16-bit clock divisors
fdt: Add function to allow aliases to refer to multiple nodes
tegra: Rename NV_PA_PMC_BASE to TEGRA2_PMC_BASE
tegra: fdt: Enable FDT support for Ventana
tegra: fdt: Enable FDT support for Seaboard
tegra: usb: Enable USB on Seaboard
tegra: usb: Add common USB defines for tegra2 boards
tegra: usb: Add USB support to nvidia boards
arm: Check for valid FDT after console is up
fdt: Avoid early panic() when there is no FDT present
tegra: usb: Add support for Tegra USB peripheral
tegra: fdt: Add function to return peripheral/clock ID
usb: Add support for txfifo threshold
tegra: usb: fdt: Add USB definitions for Tegra2 Seaboard
tegra: usb: fdt: Add additional device tree definitions for USB ports
tegra: fdt: Add clock bindings for Tegra2 Seaboard
tegra: fdt: Add clock bindings
tegra: fdt: Add additional USB binding
fdt: Add tegra-usb bindings file from linux
fdt: Add staging area for device tree binding documentation
tegra: fdt: Add device tree file for Tegra2 Seaboard from kernel
tegra: fdt: Add Tegra2x device tree file from kernel
arm: fdt: Add skeleton device tree file from kernel
fdt: Add basic support for decoding GPIO definitions
fdt: Add functions to access phandles, arrays and bools
fdt: Tidy up a few fdtdec problems
fdt: Add tests for fdtdec
fdt: Add fdtdec_find_aliases() to deal with alias nodes
arm: Tegra2: Fix ELDK42 gcc failure with inline asm stack pointer load
net: fec_mxc: allow use with cache enabled
net: force PKTALIGN to ARCH_DMA_MINALIGN
i.MX28: Enable caches by default
i.MX28: Make use of the bounce buffer
i.MX28: Do data transfers via DMA in MMC driver
MMC: Implement generic bounce buffer
i.MX28: Add cache support to MXS NAND driver
i.MX28: Add cache support into the APBH DMA driver
ARM926EJS: Implement cache operations
board/vpac270/onenand.c: Fix build errors
nhk8815: fix build errors
atmel-boards: add missing atmel_mci.h
ARM: highbank: setup env from boot source register
ARM: highbank: change env config to use nvram
ARM: highbank: add reset support
ARM: highbank: Add boot counter support
ARM: highbank: change TEXT_BASE to 0x8000
ARM: highbank: fix us_to_tick calculation
ARM: highbank: add missing get_tbclk
ARM: highbank: fix warning for calxedaxgmac_initialize
net: calxedaxgmac: fix build due to missing __aligned definition
EXYNOS: Add structure for Exynos4 DMC
EXYNOS: SMDK5250: Support all 4 UARTs
ARM: fix s3c2410 timer code
ARM: davinci: fixes for cam_enc_4xx board
omap3_spi: receive transmit mode
calimain, enbw_cmc: Fix typo in comments
Davinci: ea20: use gpio framework to access gpios
OMAP3: mt_ventoux: sets its own mtdparts
OMAP3: mt_ventoux: updated timing for FPGA
twl4030: fix potential power supply handling issues
NAND: TI: fix warnings in omap_gpmc.c
cam_enc_4xx: Rename 'images' to 'imgs'
arm: Add Prep subcommand support to bootm
OMAP3: twister: add support to boot Linux from SPL
SPL: call cleanup_before_linux() before booting Linux
OMAP3: SPL: do not call I2C init if no I2C is set.
Add cache functions to SPL for armv7
devkit8000: Implement and activate direct OS boot
omap/spl: change output of spl_parse_image_header
omap-common/spl: Add linux boot to SPL
devkit8000/spl: init GPMC for dm9000 in SPL
omap-common: Add NAND SPL linux booting
devkit8000: add config for spl command
Add cmd_spl command
mx53ard: Initialize return code with error
mx53: Make PLL2 to be the parent of UART clock
configs: imx: Use CONFIG_SF_DEFAULT_CS
mx28evk: Provide default values for SPI bus and chip select
USB: ehci-mx6: Add proper IO accessors
mx6: Read silicon revision from register
i.MX28: Drop __naked function from spl_mem_init
mxs_spi: Return proper timeout error
i.MX28: Make the stabilization delays shorter
pmic_i2c: Return error in case of invalid pmic_i2c_tx_num
mx6: Remove duplicate definition of ANATOP_BASE_ADDR
mx6: Fix reset cause for Power On Reset case
i.MX6: mx6qsabrelite: add MACH_TYPE_MX6Q_SABRELITE
i.MX6: mx6q_sabrelite: add CONFIG_REVISION_TAG
i.MX28: Enable additional DRAM address bits
mx6q: mx6qsabrelite: setup_spi() should be called in board_init to allow use for environment
mx31: add "ARM11P power gating" to get_reset_cause
mx31pdk: Fix CONFIG_SYS_MEMTEST_END
efikamx: Fix CONFIG_SYS_MEMTEST_END
mx53smd: Fix CONFIG_SYS_MEMTEST_END
mx53evk: Fix CONFIG_SYS_MEMTEST_END
mx51evk: Fix CONFIG_SYS_MEMTEST_END
i.MX6: mx6qsabrelite: add ext2 support
imximage: Remove overwriting of flash_offset
IXP: Fix GPIO_INT_ACT_LOW_SET()
IXP: Fix NAND build warning on PDNB3 and SCPU
IXP: Move PDNB3 and SCPU from Makefile to boards.cfg
IXP: Squash warnings in IXP NPE
IXP: Fix missing MACH_TYPE_{ACTUX?,PNB3,DVLHOST}
IXP: Make IXP buildable with arm-linux- toolchains
Examples: Properly append LDFLAGS to LD command
SPL: Enable YMODEM support on BeagleBone and AM335x EVM
SPL: Add YMODEM over UART load support
SPL: Add README.omap3
README: document more SPL config options
spl.c: Use __noreturn decorator
config.mk: Check for -fstack-usage support
config.mk: Make cc-option create a file under include/generated
...
Implementation of receive-transmit mode for
omap3 MCSPI.
Introduces full duplex communication, needed by
some spi devices (such as enc28j60).
Signed-off-by: jacopo mondi <mondi@cs.unibo.it> <j.mondi@voltaelectronics.com>
Instead of returning -1, it is preferred to return -ETIMEDOUT in case of timeouts.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Acked-by: Marek Vasut <marex@denx.de>
The module has 4 chip select signals. This patch supports it.
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
Move (E)CSPI register declarations into the imx-regs.h files for each supported CPU
Introduce two new macros to control conditional setup
MXC_CSPI - Used for processors with the Configurable Serial Peripheral Interface (MX3x)
MXC_ECSPI - For processors with Enhanced Configurable... (MX5x, MX6x)
Signed-off-by: Eric Nelson <eric.nelson@boundarydevices.com>
Acked-by: Dirk Behme <dirk.behme@de.bosch.com>
Acked-by: Stefano Babic <sbabic@denx.de>
Acked-by: Jason Liu <jason.hui@linaro.org>
Tested-by: Jason Liu <jason.hui@linaro.org>
Problem appears to have been present since day one but masked because alignment
aborts were not enabled. ca4b55800e "arm, arm926ejs: always do cpu critical
inits" turned on alignment aborts and uncovered this latent problem.
Signed-off-by: Ian Campbell <ijc@hellion.org.uk>
Acked-By: Jason Cooper <u-boot@lakedaemon.net>
Tested-By: Holger Brunck <holger.brunck@keymile.com>
Cc: Prafulla Wadaskar <prafulla@marvell.com>
Cc: Albert ARIBAUD <albert.u.boot@aribaud.net>
The generic spi flash driver (drivers/mtd/spi/spi_flash.c) uses the
spi low level driver's spi_xfer() function with len=0 to deassert the
SPI flash' chip select. But the i.MX28 spi driver rejects this call
due to len=0.
This patch implements an exception for len=0 with the SPI_XFER_END
flag set. This results in an extra read with the chip select being
deasserted afterwards. There seems to be no way to deassert the signal
by hand.
Signed-off-by: Matthias Fuchs <matthias.fuchs@esd.eu>
Tested-by: Fabio Estevam <fabio.estevam@freescale.com>
This allows a final, board specific, step in the claim/relase_bus
function for the SPI controller, which may be needed for some hardware
designs.
Signed-off-by: Valentin Longchamp <valentin.longchamp@keymile.com>
cc: Holger Brunck <holger.brunck@keymile.com>
cc: Prafulla Wadaskar <prafulla@marvell.com>
These two function nows ensure that the MPP is configured correctly for
the SPI controller before any SPI access, and restore the initial
configuration when the access is over.
Since the used pins for the SPI controller can differ (2 possibilities
for each signal), the used pins are configured with CONFIG_SYS_KW_SPI_MPP.
Signed-off-by: Valentin Longchamp <valentin.longchamp@keymile.com>
cc: Holger Brunck <holger.brunck@keymile.com>
cc: Prafulla Wadaskar <prafulla@marvell.com>
This was not done before, and in the case of a shared pin (for MPP0
between NF_IO[2] and CSn) this could lead to problems.
Signed-off-by: Valentin Longchamp <valentin.longchamp@keymile.com>
cc: Holger Brunck <holger.brunck@keymile.com>
cc: Prafulla Wadaskar <prafulla@marvell.com>
In anticipation of Tegra3 support, start removing/renaming
Tegra2-specific files. No functional changes (yet).
Also updated copyright to 2012.
Signed-off-by: Tom Warren <twarren@nvidia.com>
Simon Glass's proposal to fix this on Seaboard was NAK'd, so I
removed his NS16550 references and added a small delay before
SPI/UART muxing. Tested on my Seaboard with large SPI reads/writes
and saw no corruption (crc's matched) and no spurious comm chars.
Signed-off-by: Tom Warren <twarren@nvidia.com>
Acked-by: Simon Glass <sjg@chromium.org>
Tested-by: Jimmy Zhang <jimmzhang@nvidia.com>
Add the SPI / UART switch logic into the Tegra2 SPI driver so that it
can co-exist with the NS16550 UART.
We need the ns16550.h header for NS16550_t for now.
Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Warren <twarren@nvidia.com>