Commit graph

261 commits

Author SHA1 Message Date
Yen Lin
60acde43d7 spi: tegra: clear RDY bit prior to every transfer
The RDY bit indicates that a transfer is complete. This needs to be
cleared by SW before every single HW transaction, rather than only
at the start of each SW transaction (those being made up of n HW
transactions).

It seems that earlier HW may have cleared this bit autonomously when
starting a new transfer, and hence this code was not needed in practice.
However, this is generally a good idea in all cases. In Tegra124, the
HW behaviour appears to have changed, and SW must explicitly clear this
bit. Otherwise, SW will believe that transfers have completed when they
have not, and may e.g. read stale data from the RX FIFO.

Signed-off-by: Yen Lin <yelin@nvidia.com>
[swarren, rewrote commit description, unified duplicate RDY clearing code
and moved it right before the start of the HW transaction, unconditionally
exit loop after reading RX data, rather than checking if TX FIFO is empty,
since it is guaranteed to be]
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Jagannadha Sutradharudu Teki <jaganna@xilinx.com>
2013-12-19 00:00:51 +05:30
Nobuhiro Iwamatsu
16f47c9c51 spi: Add support SH Quad SPI driver
This patch adds a driver for Renesas SoC's Quad SPI bus.
This supports with 8 bits per transfer to use with SPI flash.

Signed-off-by: Kouei Abe <kouei.abe.cp@renesas.com>
Signed-off-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Signed-off-by: Jagannadha Sutradharudu Teki <jaganna@xilinx.com>
2013-12-18 23:23:41 +05:30
Tom Rini
65b7fe28a1 Merge branch 'spi' of git://git.denx.de/u-boot-x86 2013-12-10 09:36:23 -05:00
Mike Frysinger
6122813fa2 sandbox: spi: Add SPI emulation bus
This adds a SPI framework for people to hook up simulated SPI clients.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
2013-12-09 12:22:18 -07:00
Simon Glass
0efc02499f spi_flash: Add spi_flash_probe_fdt() to locate SPI by FDT node
This allows us to put the SPI flash chip inside the SPI interface node,
with U-Boot finding the correct bus and chip select automatically.

Signed-off-by: Simon Glass <sjg@chromium.org>
2013-12-09 12:22:12 -07:00
Axel Lin
9bac8f7769 spi: bfin_spi6xx: Remove unnecessary test for bus and pins[bus]
For invalid bus number, current code returns NULL in the default case of
switch-case statements. In additional, pins[bus] is always not NULL because
it is the address of specific row of the two-dimensional array.
Thus this patch removes these unnecessary test.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Scott Jiang <scott.jiang.linux@gmail.com>
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
2013-12-06 16:06:51 +08:00
Axel Lin
727cbe14b2 spi: bfin_spi: Remove unnecessary test for bus and pins[bus]
For invalid bus number, current code returns NULL in the default case of
switch-case statements. In additional, pins[bus] is always not NULL because
it is the address of specific row of the two-dimensional array.
Thus this patch removes these unnecessary test.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Scott Jiang <scott.jiang.linux@gmail.com>
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
2013-12-06 16:06:51 +08:00
Nikita Kiryanov
5753d09b10 spi: omap3: add support for more word lengths
Current implementation only supports 8 bit word lengths, even though
omap3 can handle anything between 4 and 32.

Update the spi interface to support changing the SPI word length,
and implement it in omap3_spi driver to support the full range of
possible word lengths.
This implementation is backwards compatible by defaulting to the old
behavior of 8 bit word lengths.
Also, it required a change to the omap3_spi non static I/O functions,
but since they are not used anywhere else, no collateral changes are required.

Cc: Tom Rini <trini@ti.com>
Cc: Jagannadha Sutradharudu Teki <jagannadh.teki@gmail.com>
Cc: Igor Grinberg <grinberg@compulab.co.il>
Signed-off-by: Nikita Kiryanov <nikita@compulab.co.il>
2013-11-12 10:02:44 +01:00
Nikita Kiryanov
54a759c880 spi: omap3: remove semicolon from #define
Remove unnecessary semicolon from #define SPI_WAIT_TIMEOUT

Cc: Tom Rini <trini@ti.com>
Cc: Jagannadha Sutradharudu Teki <jagannadh.teki@gmail.com>
Cc: Igor Grinberg <grinberg@compulab.co.il>
Cc: Gerhard Sittig <gsi@denx.de>
Signed-off-by: Nikita Kiryanov <nikita@compulab.co.il>
2013-11-12 10:00:36 +01:00
Masahiro Yamada
710f1d3d5f drivers: convert makefiles to Kbuild style
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
2013-10-31 13:26:01 -04:00
Timo Herbrecher
6d5ce1bd00 spi: mxc_spi: Fix double incrementing read pointer for unaligned buffers
If dout buffer is not 32 bit-aligned or data to transmit is not multiple
of 32 bit the read data pointer is already incremented on single byte reads.

Signed-off-by: Timo Herbrecher <t.herbrecher@gateware.de>
Signed-off-by: Jagannadha Sutradharudu Teki <jaganna@xilinx.com>
2013-10-16 00:14:30 +05:30
Jagannadha Sutradharudu Teki
e7b1e452ff spi: Add GPL-2.0+ SPDX-License-Identifier for missing files
Added GPL-2.0+ SPDX-License-Identifier for missed spi
source files.

Signed-off-by: Jagannadha Sutradharudu Teki <jaganna@xilinx.com>
2013-10-16 00:14:01 +05:30
Wolfgang Denk
93e1459641 Coding Style cleanup: replace leading SPACEs by TABs
Signed-off-by: Wolfgang Denk <wd@denx.de>
[trini: Drop changes for PEP 4 following python tools]
Signed-off-by: Tom Rini <trini@ti.com>
2013-10-14 16:06:54 -04:00
Wolfgang Denk
3765b3e7bd Coding Style cleanup: remove trailing white space
Signed-off-by: Wolfgang Denk <wd@denx.de>
2013-10-14 16:06:53 -04:00
Rajeshwari Shinde
c4a796329d spi: exynos: Support word transfers
Since SPI register access is so expensive, it is worth transferring data
a word at a time if we can. This complicates the driver unfortunately.

Use the byte-swapping feature to avoid having to convert to/from big
endian in software.

This change increases speed from about 2MB/s to about 4.5MB/s.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Rajeshwari S Shinde <rajeshwari.s@samsung.com>
Reviewed-by: Jagannadha Sutradharudu Teki <jagannadh.teki@gmail.com>
2013-10-08 18:18:12 +05:30
Rajeshwari Shinde
120af1572a spi: exynos: Minimise access to SPI FIFO level
Accessing SPI registers is slow, but access to the FIFO level register
in particular seems to be extraordinarily expensive (I measure up to
600ns). Perhaps it is required to synchronise with the SPI byte output
logic which might run at 1/8th of the 40MHz SPI speed (just a guess).

Reduce access to this register by filling up and emptying FIFOs
more completely, rather than just one word each time around the inner
loop.

Since the rxfifo value will now likely be much greater that what we read
before we fill the txfifo, we only fill the txfifo halfway. This is
because if the txfifo is empty, but the rxfifo has data in it, then writing
too much data to the txfifo may overflow the rxfifo as data arrives.

This speeds up SPI flash reading from about 1MB/s to about 2MB/s on snow.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Rajeshwari S Shinde <rajeshwari.s@samsung.com>
Reviewed-by: Jagannadha Sutradharudu Teki <jagannadh.teki@gmail.com>
2013-10-08 18:18:11 +05:30
Rajeshwari Shinde
8d203afdd3 spi: exynos: Support a delay after deactivate
For devices that need some time to react after a spi transaction
finishes, add the ability to set a delay.

Implement this as a delay on the first/next transaction to avoid
any delay in the fairly common case where a SPI transaction is
followed by other processing.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Rajeshwari S Shinde <rajeshwari.s@samsung.com>
Reviewed-by: Jagannadha Sutradharudu Teki <jagannadh.teki@gmail.com>
2013-10-08 18:18:11 +05:30
Matt Porter
1d0933eaf9 spi: add TI QSPI driver
Adds a SPI master driver for the TI QSPI peripheral.
- Added quad read support.
- Added memory mapped support.

Signed-off-by: Matt Porter <matt.porter@linaro.org>
Signed-off-by: Sourav Poddar <sourav.poddar@ti.com>
Signed-off-by: Jagannadha Sutradharudu Teki <jaganna@xilinx.com>
2013-10-07 17:55:51 +05:30
Marek Vasut
a928a36ff9 spi: mxs_spi: Configure chipselect after block reset
The chipselect must be written into the CTRL0 register after the SSP
block is reset, otherwise the block will always use ChipSelect #0.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Fabio Estevam <fabio.estevam@freescale.com>
Cc: Jagannadha Sutradharudu Teki <jagannadh.teki@gmail.com>
Cc: Otavio Salvador <otavio@ossystems.com.br>
Cc: Stefano Babic <sbabic@denx.de>
Acked-by: Stefano Babic <sbabic@denx.de>
2013-08-27 19:39:39 +05:30
Prabhakar Kushwaha
997399fa42 powerpc: Fix CamelCase checkpatch warnings
85xx, 86xx PowerPC folders have code variables with CamelCase naming conventions.
because of this code checkpatch script generates "WARNING: Avoid CamelCase".

Convert variables name to normal naming convention and modify board, driver
files with updated the new structure.

Signed-off-by: Prabhakar Kushwaha <prabhakar@freescale.com>
Acked-by: York Sun <yorksun@freescale.com>
2013-08-20 09:57:51 -07:00
Jagannadha Sutradharudu Teki
1465d055f9 spi: Add zynq spi controller driver
Zynq spi controller driver supports 2 buses and
3 chipselects on each bus.

Signed-off-by: Jagannadha Sutradharudu Teki <jaganna@xilinx.com>
Acked-by: Siva Durga Prasad Paladugu <sivadur@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
2013-08-07 01:09:47 +05:30
Axel Lin
583fe6c3d8 spi: mpc8xxx_spi: Use DIV_ROUND_UP instead of open-coded
Use DIV_ROUND_UP to simplify the code.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
2013-08-06 23:58:24 +05:30
Axel Lin
a444aa7a1c spi: fsl_espi: Use DIV_ROUND_UP instead of open-coded
Use DIV_ROUND_UP to simplify the code.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
2013-08-06 23:58:09 +05:30
Axel Lin
327b5c9f7c spi: bfin_spi: Use DIV_ROUND_UP instead of open-coded
Use DIV_ROUND_UP to simplify the code.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Scott Jiang <scott.jiang.linux@gmail.com>
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
2013-07-31 16:56:04 +08:00
Wolfgang Denk
1a4596601f Add GPL-2.0+ SPDX-License-Identifier to source files
Signed-off-by: Wolfgang Denk <wd@denx.de>
[trini: Fixup common/cmd_io.c]
Signed-off-by: Tom Rini <trini@ti.com>
2013-07-24 09:44:38 -04:00
Tom Rini
fbbbc86e8e Merge branch 'master' of git://git.denx.de/u-boot-arm
Fix a trivial conflict in arch/arm/dts/exynos5250.dtsi about gpio and
serial.

Conflicts:
	arch/arm/dts/exynos5250.dtsi

Signed-off-by: Tom Rini <trini@ti.com>
2013-07-12 10:36:48 -04:00
Albert ARIBAUD
e6c7f86f03 Merge branch 'u-boot-imx/master' into 'u-boot-arm/master' 2013-06-28 17:51:13 +02:00
Dirk Behme
9a30903b44 spi: mxc_spi: Update pre and post divider algorithm
The spi clock divisor is of the form x * (2**y),  or  x  << y, where x is
1 to 16, and y is 0 to 15. Note the similarity with floating point numbers.
Convert the desired divisor to the smallest number which is >= desired divisor,
and can be represented in this form. The previous algorithm chose a divisor
which could be almost twice as large as needed.

Signed-off-by: Troy Kisky <troy.kisky@boundarydevices.com>
Signed-off-by: Dirk Behme <dirk.behme@gmail.com>
2013-06-26 16:23:30 +02:00
Dirk Behme
8d4c4ffb95 spi: mxc_spi: Fix pre and post divider calculation
Fix two issues with the calculation of pre_div and post_div:

1. pre_div: While the calculation of pre_div looks correct, to set the
CONREG[15-12] bits pre_div needs to be decremented by 1:

The i.MX 6Dual/6Quad Applications Processor Reference Manual (IMX6DQRM
Rev. 0, 11/2012) states:

CONREG[15-12]: PRE_DIVIDER
0000 Divide by 1
0001 Divide by 2
0010 Divide by 3
...
1101 Divide by 14
1110 Divide by 15
1111 Divide by 16

I.e. if we want to divide by 2, we have to write 1 to CONREG[15-12].

2. In case the post divider becomes necessary, pre_div will be divided by
16. So set pre_div to 16, too. And not 15.

Both issues above are tested using the following examples:

clk_src = 60000000 (60MHz, default i.MX6 ECSPI clock)

a) max_hz == 23000000 (23MHz, max i.MX6 ECSPI read clock)

-> pre_div =  3 (divide by 3 => CONREG[15-12] == 2)
-> post_div = 0 (divide by 1 => CONREG[11- 8] == 0)
               => 60MHz / 3 = 20MHz SPI clock

b) max_hz == 2000000 (2MHz)

-> pre_div =  16 (divide by 16 => CONREG[15-12] == 15)
-> post_div = 1  (divide by  2 => CONREG[11- 8] == 1)
               => 60MHz / 32 = 1.875MHz SPI clock

c) max_hz == 1000000 (1MHz)

-> pre_div =  16 (divide by 16 => CONREG[15-12] == 15)
-> post_div = 2  (divide by  4 => CONREG[11- 8] == 2)
               => 60MHz / 64 = 937.5kHz SPI clock

d) max_hz == 500000 (500kHz)

-> pre_div =  16 (divide by 16 => CONREG[15-12] == 15)
-> post_div = 3  (divide by  8 => CONREG[11- 8] == 3)
               => 60MHz / 128 = 468.75kHz SPI clock

Signed-off-by: Dirk Behme <dirk.behme@gmail.com>
2013-06-26 16:22:51 +02:00
Hung-ying Tyan
f3424c554c cros: exynos: add SPI support for cros_ec
This patch adds SPI support for carrying out the cros_ec protocol.

Signed-off-by: Hung-ying Tyan <tyanh@chromium.org>
Signed-off-by: Randall Spangler <rspangler@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Simon Glass <sjg@chromium.org>
2013-06-26 10:13:24 -04:00
Axel Lin
9675fed474 spi: mxc_spi: Use DIV_ROUND_UP at appropriate places
This change slightly improves readability.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Reviewed-by: Jagannadha Sutradharudu Teki <jagannadh.teki@gmail.com>
2013-06-22 23:08:01 +05:30
Axel Lin
0cb8394f81 spi: cf_qspi: Use DIV_ROUND_UP at appropriate place
This change slightly improves readability.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Richard Retanubun <richardretanubun@ruggedcom.com>
Reviewed-by: Jagannadha Sutradharudu Teki <jagannadh.teki@gmail.com>
2013-06-22 23:08:01 +05:30
Tom Rini
f0df254663 Merge branch 'master' of git://git.denx.de/u-boot-spi 2013-06-13 15:18:35 -04:00
Axel Lin
ba1d1c2d9b spi: tegra20_sflash: Remove redundant code to set bus and cs of struct spi_slave
It's done in spi_alloc_slave(), thus remove the redundant code.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Marek Vasut <marex@denx.de>
Reviewed-by: Jagannadha Sutradharudu Teki <jagannadh.teki@gmail.com>
2013-06-13 22:55:30 +05:30
Axel Lin
d6f64d4a11 spi: tegra114_spi: Convert to use spi_alloc_slave()
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Marek Vasut <marex@denx.de>
Reviewed-by: Jagannadha Sutradharudu Teki <jagannadh.teki@gmail.com>
2013-06-13 22:55:24 +05:30
Axel Lin
0368292954 spi: armada100_spi: Remove unnecessary NULL test for dout and din
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Reviewed-by: Marek Vasut <marex@denx.de>
Acked-by: Ajay Bhargav <ajay.bhargav@einfochips.com>
Reviewed-by: Jagannadha Sutradharudu Teki <jagannadh.teki@gmail.com>
2013-06-13 22:55:18 +05:30
Rajeshwari Shinde
e4eaef8910 spi: exynos: Support SPI_PREAMBLE mode
Support interfaces with a preamble before each received message.

We handle this when the client has requested a SPI_XFER_END, meaning
that we must close of the transaction. In this case we read until we
see the preamble (or a timeout occurs), skipping all data before and
including the preamble. The client will receive only data bytes after
the preamble.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Rajeshwari Shinde <rajeshwari.s@samsung.com>
Reviewed-by: Jagannadha Sutradharudu Teki <jagannadh.teki@gmail.com>
2013-06-03 00:04:40 +05:30
Albert ARIBAUD
a19b0dd62d Merge branch 'u-boot/master' into 'u-boot-arm/master'
Conflicts:
	common/cmd_fpga.c
	drivers/usb/host/ohci-at91.c
2013-05-30 14:45:06 +02:00
Scott Jiang
d4d4f90377 bfin: discard invalid data and clear RXS in bf5xx spi driver
There may be dirty data in RDBR, so we should discard invalid data.
This operation also clears RXS bit in STAT register.

Signed-off-by: Scott Jiang <scott.jiang.linux@gmail.com>
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
2013-05-13 16:26:27 +08:00
Scott Jiang
e76276df74 bfin: Remove spi dma function in bf5xx.
BF5xx rx dma causes spi flash random read error.
Accually spi controller has problems both on tx and rx dma.
So remove spi dma support in u-boot.

Signed-off-by: Scott Jiang <scott.jiang.linux@gmail.com>
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
2013-05-13 16:26:27 +08:00
Bo Shen
e0d2d3bd29 spi: atmel_spi: using ip version to check whether has wdrbt
Using IP version to check whether it has wdrbt bit in mode register

Tested in at91sam9x5ek and at91sam9n12ek.

Signed-off-by: Bo Shen <voice.shen@atmel.com>
[fix warning about incompatible parameter]
Signed-off-by: Josh Wu <josh.wu@atmel.com>
Signed-off-by: Andreas Bießmann <andreas.devel@googlemail.com>
2013-05-12 16:36:11 +02:00
Stefan Roese
0499218dbc imx: Move some header files from arch-mxs to imx-common
The following headers are moved to a i.MX common location:

- regs-common.h
- regs-apbh.h
- regs-bch.h
- regs-gpmi.h
- dma.h

This way this header can be re-used also by other i.MX platforms.
For example the i.MX6 which will need it for the upcoming NAND
support.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Stefano Babic <sbabic@denx.de>
Cc: Marek Vasut <marex@denx.de>
Cc: Fabio Estevam <fabio.estevam@freescale.com>
2013-04-22 10:22:22 +02:00
Albert ARIBAUD
8dc16cf9dd Merge branch 'u-boot-imx/master' into 'u-boot-arm/master' 2013-04-14 10:38:37 +02:00
Fabio Estevam
0f1411bc8d spi: mxc_spi: Set master mode for all channels
The glitch in the SPI clock line, which commit 3cea335c34 (spi: mxc_spi: Fix spi
clock glitch durant reset) solved, is back now and itwas re-introduced by
commit d36b39bf0d (spi: mxc_spi: Fix ECSPI reset handling).

Actually the glitch is happening due to always toggling between slave mode
and master mode by configuring the CHANNEL_MODE bits in this reset function.

Since the spi driver only supports master mode, set the mode for all channels
always to master mode in order to have a stable, "glitch-free" SPI clock line.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
2013-04-13 17:46:42 +02:00
Albert ARIBAUD
1812201997 Merge branch 'u-boot/master' into 'u-boot-arm/master'
Conflicts:
	drivers/video/exynos_fb.c
2013-04-12 22:07:57 +02:00
Albert ARIBAUD
fed029f3c3 Merge branch 'u-boot-samsung/master' into 'u-boot-arm/master' 2013-04-04 15:44:57 +02:00
Albert ARIBAUD
be08abc242 Merge branch 'u-boot-imx/master' into 'u-boot-arm/master' 2013-04-04 11:49:32 +02:00
Dirk Behme
d36b39bf0d spi: mxc_spi: Fix ECSPI reset handling
Reviewing the ECSPI reset handling shows two issues:

1. For the enable/reset bit (MXC_CSPICTRL_EN) in the control reg
   (ECSPIx_CONGREG) the i.MX6 technical reference manual states:

   -- cut --
   ECSPIx_CONREG[0]: EN: Writing zero to this bit disables the block
   and resets the internal logic with the exception of the ECSPI_CONREG.
   -- cut --

   Note the exception mentioned: The CONREG itself isn't reset.

   Fix this by manually writing the reset value 0 to the whole register.
   This sets the EN bit to zero, too (i.e. includes the old
   ~MXC_CSPICTRL_EN).

2. We want to reset the whole SPI block here. So it makes no sense
   to first read the old value of the CONREG and write it back, later.
   This will give us the old (historic/random) value of the CONREG back.
   And doesn't reset the CONREG.

   To get a clean CONREG after the reset of the block, too, don't use
   the old (historic/random) value of the CONREG while doing the reset.
   And read the clean CONREG after the reset.

This was found while working on a SPI boot device where the i.MX6 boot
ROM has already initialized the SPI block. The initialization by the
boot ROM might be different to what the U-Boot driver wants to configure.
I.e. we need a clean reset of SPI block, including the CONREG.

Signed-off-by: Dirk Behme <dirk.behme@de.bosch.com>
CC: Stefano Babic <sbabic@denx.de>
CC: Fabio Estevam <fabio.estevam@freescale.com>
2013-04-04 10:23:09 +02:00
York Sun
472d546054 Consolidate bool type
'bool' is defined in random places. This patch consolidates them into a
single header file include/linux/types.h, using stdbool.h introduced in C99.

All other #define, typedef and enum are removed. They are all consistent with
true = 1, false = 0.

Replace FALSE, False with false. Replace TRUE, True with true.
Skip *.py, *.php, lib/* files.

Signed-off-by: York Sun <yorksun@freescale.com>
2013-04-01 16:33:52 -04:00
Vivek Gautam
7d17958408 spi: exynos: Fix compiler warnings for non-dt systems
Enclosing process_nodes() and spi_get_config() inside
CONFIG_OF_CONTROL, since they are compiled only for DT systems.

This fixes following warning:
exynos_spi.c:391:12: warning: 'process_nodes' defined but not used [-Wunused-function]

Signed-off-by: Vivek Gautam <gautam.vivek@samsung.com>
Acked-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
2013-03-29 11:16:25 +09:00
Albert ARIBAUD
009d75ccc1 Merge branch 'u-boot/master' into 'u-boot-arm/master'
Conflicts:
	drivers/spi/tegra20_sflash.c
	include/fdtdec.h
	lib/fdtdec.c
2013-03-28 18:50:01 +01:00
Allen Martin
77c42e80b9 tegra114: add SPI driver
Add driver for tegra114 SPI controller.  This controller is not
compatible with either the tegra20 or tegra30 controllers, so it
requires a new driver.

Signed-off-by: Allen Martin <amartin@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
2013-03-25 09:56:07 -07:00
Allen Martin
78f47b7353 spi: add common fdt SPI driver interface
Add a common interface to fdt based SPI drivers.  Each driver is
represented by a table entry in fdt_spi_drivers[].  If there are
multiple SPI drivers in the table, the first driver to return success
from spi_init() will be registered as the SPI driver.

Signed-off-by: Allen Martin <amartin@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
2013-03-25 09:56:06 -07:00
Allen Martin
6b3a03e112 tegra20: spi: move fdt probe to spi_init
Make the tegra20 SPI driver similar to the tegra30 (and soon to be
tegra114) SPI drivers in preparation of common fdt SPI driver front
end.

Signed-off-by: Allen Martin <amartin@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
2013-03-25 09:56:06 -07:00
Allen Martin
7a49ba6e5b tegra: spi: pull register structs out of headers
Move register structs from headers into .c files and use common name.
This is in preparation of making common fdt front end for SPI
drivers.

Signed-off-by: Allen Martin <amartin@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
2013-03-25 09:56:05 -07:00
Allen Martin
2a3c5bc29c tegra: spi: remove non fdt support
Remove non fdt support from tegra20 and tegra30 SPI drivers in
preparation of new common fdt based SPI driver front end.

Signed-off-by: Allen Martin <amartin@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
2013-03-25 09:56:05 -07:00
Allen Martin
ff1da6fb5f tegra: spi: rename tegra SPI drivers
Rename tegra SPI drivers to tegra20_flash and tegra20_slink in
preparation for commonization and addition of tegra114_spi.

Signed-off-by: Allen Martin <amartin@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
2013-03-25 09:56:05 -07:00
Allen Martin
9000652da0 tegra: remove support for UART SPI switch
This feature was only used for tegra20 seaboard that had a pinmux
conflict on the SPI pins.  These boards were never manufactured, so
remove this support to clean up SPI driver.

Signed-off-by: Allen Martin <amartin@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
2013-03-25 09:56:05 -07:00
Simon Glass
5e6fb69778 x86: spi: Set maximum write size for ICH
This SPI controller can only write 64 bytes at a time. Add this restriction
in so that 'sf write' works correct for blocks larger than 64 bytes.

Signed-off-by: Simon Glass <sjg@chromium.org>
2013-03-19 08:45:37 -07:00
Simon Glass
1853030e21 x86: spi: Add Intel ICH driver
This supports Intel ICH7/9. The Intel controller is a little unusual in
that it is mostly intended for use with SPI flash, and has some
optimisations and features specifically for that application. In
particular it is not possible to support ongoing transactions that
continue over many calls with SPI_XFER_BEGIN and SPI_XFER_END.

This driver supports writes of up to 64 bytes at a time, the limit
for the controller. Future work will improve this.

Signed-off-by: Bernie Thompson <bhthompson@chromium.org>
Signed-off-by: Duncan Laurie <dlaurie@chromium.org>
Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Signed-off-by: Vadim Bendebury <vbendeb@chromium.org>
Signed-off-by: Gabe Black <gabeblack@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
2013-03-19 08:45:36 -07:00
Simon Glass
d3504fee73 spi: Use spi_alloc_slave() in each SPI driver
Rather than each driver having its own way to allocate a SPI slave,
use the new allocation function everywhere. This will make it easier
to extend the interface without breaking drivers.

Signed-off-by: Simon Glass <sjg@chromium.org>
2013-03-19 08:45:36 -07:00
Simon Glass
ba6c3ce9bd spi: Add function to allocate a new SPI slave
At present it is difficult to extend the SPI structure since all
drivers allocate it themselves, and few of them zero all fields. Add
a new function spi_alloc_slave() which can be used by SPI drivers
to perform this allocation, and thus ensure that all drivers can
better cope with SPI structure changes.

Signed-off-by: Simon Glass <sjg@chromium.org>
2013-03-19 08:45:36 -07:00
Albert ARIBAUD
6579d15c58 Merge branch 'u-boot-imx/master' into 'u-boot-arm/master' 2013-03-15 15:18:31 +01:00
Marek Vasut
d3f26a2700 mxs: spi: Remove CONFIG_MXS_SPI_DMA_ENABLE
The CONFIG_MXS_SPI_DMA_ENABLE is no longer relevant as the SPI DMA
has proven to work correctly. Remove this configuration option.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Fabio Estevam <fabio.estevam@freescale.com>
Cc: Otavio Salvador <otavio@ossystems.com.br>
Cc: Stefano Babic <sbabic@denx.de>
2013-03-07 17:22:56 +01:00
Marek Vasut
c96e78ccfe mxs: spi: Fix the MXS SPI for mx23
The MX23 has slightly different register layout. Adjust the SPI
driver to match the layout, both the PIO and DMA part.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Fabio Estevam <fabio.estevam@freescale.com>
Cc: Otavio Salvador <otavio@ossystems.com.br>
Cc: Stefano Babic <sbabic@denx.de>
2013-03-07 17:22:56 +01:00
Marek Vasut
3430e0bd2a mxs: mmc: spi: dma: Better wrap the MXS differences
This patch streamlines the differences between the MX23 and MX28 by
implementing a few helper functions to handle different DMA channel
mapping, different clock domain for SSP block and fixes a few minor
bugs.

First of all, the DMA channel mapping is now fixed in dma.h by defining
the actual channel map for both MX23 and MX28. Thus, MX23 now does no
longer use MX28 channel map which was wrong. Also, there is a fix for
MX28 DMA channel map, where the last four channels were incorrect.

Next, because correct DMA channel map is in place, the mxs_dma_init_channel()
call now bases the channel ID starting from SSP port #0. This removes the
need for DMA channel offset being added and cleans up the code. For the
same reason, the SSP0 offset can now be used in mxs_dma_desc_append(), thus
no need to adjust dma channel number in the driver either.

Lastly, the SSP clock ID is now retrieved by calling mxs_ssp_clock_by_bus()
which handles the fact that MX23 has shared SSP clock for both ports, while
MX28 has per-port SSP clock.

Finally, the mxs_ssp_bus_id_valid() pulls out two implementations of the
same functionality from MMC and SPI driver into common code.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Fabio Estevam <fabio.estevam@freescale.com>
Cc: Otavio Salvador <otavio@ossystems.com.br>
Cc: Stefano Babic <sbabic@denx.de>
2013-03-07 17:22:56 +01:00
Scott Jiang
4a207e8b9a blackfin: add bf6xx spi driver
Spi driver for bf60x is different from old one, so implement a new
driver for it.

Signed-off-by: Scott Jiang <scott.jiang.linux@gmail.com>
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Bob Liu <lliubbo@gmail.com>
Signed-off-by: Sonic Zhang <sonic.adi@gmail.com>
2013-03-04 13:42:07 +08:00
Tom Rini
951c6baaf4 Merge branch 'master' of git://git.denx.de/u-boot-arm 2013-02-12 10:18:31 -05:00
Allen Martin
b19f57491a tegra: add SPI SLINK driver
Add driver for tegra SPI "SLINK" style driver.  This controller is
similar to the tegra20 SPI "SFLASH" controller.  The difference is
that the SLINK controller is a genernal purpose SPI controller and the
SFLASH controller is special purpose and can only talk to FLASH
devices.  In addition there are potentially many instances of an SLINK
controller on tegra and only a single instance of SFLASH.  Tegra20 is
currently ths only version of tegra that instantiates an SFLASH
controller.

This driver supports basic PIO mode of operation and is configurable
(CONFIG_OF_CONTROL) to be driven off devicetree bindings.  Up to 4
devices per controller may be attached, although typically only a
single chip select line is exposed from tegra per controller so in
reality this is usually limited to 1.

To enable this driver, use CONFIG_TEGRA_SLINK

Signed-off-by: Allen Martin <amartin@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>
2013-02-11 10:35:25 -07:00
Allen Martin
8f1b46b104 tegra: spi: add fdt support to tegra SPI SFLASH driver
Add support for configuring tegra SPI driver from devicetree.
Support is keyed off CONFIG_OF_CONTROL.  Add entry in seaboard dts
file for spi controller to describe seaboard spi.

Signed-off-by: Allen Martin <amartin@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>
2013-02-11 10:35:24 -07:00
Jason Wu
85e9c65f8a spi: xilinx_spi: Perform software reset during slave setup
to make sure it is in the clear state.

Signed-off-by: Jason Wu <huanyu@xilinx.com>
2013-02-04 12:09:49 +01:00
Otavio Salvador
bf48fcb61b mxs: clock: Use 'mxs' prefix for methods
Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
Cc: Fabio Estevam <fabio.estevam@freescale.com>
Cc: Marek Vasut <marex@denx.de>
Cc: Stefano Babic <sbabic@denx.de>
2013-01-21 12:05:20 +01:00
Marek Vasut
14e26bcfa7 mxs: ssp: Pull out the SSP bus to regs conversion
Create function which converts SSP bus number to SSP register pointer.
This functionality is reimplemented multiple times in the code, thus
make one common implementation. Moreover, make it a switch(), since the
SSP ports are not mapped in such nice linear fashion on MX23, therefore
having it a switch will simplify things there.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Andy Fleming <afleming@freescale.com>
Cc: Fabio Estevam <fabio.estevam@freescale.com>
Cc: Stefano Babic <sbabic@denx.de>
2013-01-21 12:05:19 +01:00
Albert ARIBAUD
1199c377cf Merge branch 'u-boot-samsung/master' into 'u-boot-arm/master' 2013-01-14 15:21:00 +01:00
Albert ARIBAUD
612404c28a Merge 'u-boot-atmel/master' into 'u-boot-arm/master' 2013-01-09 20:01:48 +01:00
Albert ARIBAUD
9d86f0c30b kirkwood: make MPP arrays static const
This saves stack and code memory for local copy, and
consumes initialized data memory. For 22 of the 29
kirkwood-based boards, this results in a global saving
of about 30 bytes. For 7 of them, it results in an
increase of 6 to 14 bytes.

Signed-off-by: Albert ARIBAUD <albert.u.boot@aribaud.net>
2013-01-09 04:12:10 +05:30
Rajeshwari Shinde
4d3acb9df3 SPI: EXYNOS: Add FDT support to driver.
This patch adds FDT support to the SPI driver.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Rajeshwari Shinde <rajeshwari.s@samsung.com>
Acked-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
2013-01-08 10:54:34 +09:00
ajoy
cc1182beea OMAP3 SPI : Fixed bugs related to SPI transfer
Added posted writes (read after writes) to effect the
change immediately for channel confiuration and channel
enable register

Disable the channel to purge receieve data in TX_ONLY
mode transfer otherwise rx data will get affected by
the next immediate RX_ONLY mode transfer

Wait for the EOT bit to be set after last byte has been
loaded to TX shift register in the the TX_ONLY mode.This
ensures TX data has been completely shifted out

Disable the channel in RX_ONLY mode before reading the
last data from  RXX register to prevent the SPI slave
to transmit next word

Signed-off-by: Ajoy Kumar Das <akdas75@yahoo.in>
Cc: Tom Rini <trini@ti.com>
Cc: jacopo mondi <j.mondi@voltaelectronics.com>
2012-12-10 08:55:25 -07:00
Bo Shen
ac81e1ccf7 spi: atmel: sam9m10g45 also support WDRBT bit
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>
2012-12-09 22:40:13 +01:00
Albert ARIBAUD
b8a7c46796 Merge branch 'u-boot-imx/master' into 'u-boot-arm/master' 2012-11-25 13:01:58 +01:00
Fabio Estevam
3cea335c34 spi: mxc_spi: Fix spi clock glitch durant reset
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>
2012-11-19 08:49:00 +01:00
Fabio Estevam
de5bf02cb1 spi: mxc_spi: Fix handling of chip select
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>
2012-11-19 08:49:00 +01:00
Rajeshwari Shinde
1bf43b829e SPI: Add SPI Driver for EXYNOS.
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>
2012-11-15 21:08:21 +09:00
Albert ARIBAUD
c68436fa42 Merge remote-tracking branch 'u-boot-ti/master' 2012-10-26 07:00:28 +02:00
Peter Korsgaard
22cbeed454 omap3_spi: introduce CONFIG_OMAP3_SPI_D0_D1_SWAPPED
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>
2012-10-25 11:30:50 -07:00
Shaohui Xie
9905757e29 powerpc/espi: remove write command length check
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>
2012-10-22 15:52:46 -05:00
Tom Warren
150c24936b Tegra20: Move some include files to arch-tegra for sharing with Tegra30
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>
2012-10-15 11:54:06 -07:00
Tom Rini
495dbd72dd Merge branch 'master' of git://git.denx.de/u-boot-arm 2012-09-21 14:53:13 -07:00
Albert ARIBAUD
d193c1b6eb Merge remote-tracking branch 'u-boot-imx/master' 2012-09-21 00:26:19 +02:00
Richard Retanubun
59d0612252 ColdFire: Queued SPI driver
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>
2012-09-20 20:39:27 +08:00
Ira W. Snyder
f138ca1373 mpc8xxx_spi: fix SPI support on MPC8308RDB
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>
2012-09-18 16:16:44 -05:00
Stephan Linz
03afad2fc9 spi: xilinx: Remove unused variable
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>
2012-09-11 09:24:56 +02:00
Tom Warren
29f3e3f248 Tegra: Change Tegra20 to Tegra in common code, prep for T30
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>
2012-09-10 13:01:24 -07:00
Marek Vasut
e9f7eafd3c MX28: SPI: Fix the DMA chaining
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>
2012-09-06 14:17:55 +02:00
Marek Vasut
88d1555968 MX28: SPI: Fix the DMA DCache race condition
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>
2012-09-06 14:17:55 +02:00
Valentin Longchamp
8203b201ea kw_spi: fix clock prescaler computation
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>
2012-09-03 17:28:51 +05:30
Bo Shen
65c575506d spi: atmel: add WDRBT bit to avoid receive overrun
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>
2012-09-01 17:06:14 +02:00
Marek Vasut
2c4321444a MX28: SPI: Supercharge the SPI driver
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>
2012-09-01 14:58:29 +02:00
Matt Sealey
c6b52c4927 spi: fix mxs_spi_slave structure allocation to clear memory
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>
2012-09-01 14:58:27 +02:00
Matt Sealey
784097ae5a spi: fix mxc_spi_slave structure allocation to clear memory
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>
2012-09-01 14:58:27 +02:00