mirror of
https://github.com/AsahiLinux/u-boot
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5e61c4e89d
Since the commit 1289e96797 ("sandbox: spi: Drop command-line SPI
option"), "--spi_sf" command line option is no longer supported.
So update the following documents to sync them up with the change.
doc/arch/sandbox.rst
doc/SPI/README.sandbox-spi
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
42 lines
1.1 KiB
Text
42 lines
1.1 KiB
Text
Sandbox SPI/SPI Flash Implementation
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====================================
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U-Boot supports SPI and SPI flash emulation in sandbox. This must be enabled
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via a device tree.
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For example:
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spi@0 {
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#address-cells = <1>;
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#size-cells = <0>;
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reg = <0 1>;
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compatible = "sandbox,spi";
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cs-gpios = <0>, <&gpio_a 0>;
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spi.bin@0 {
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reg = <0>;
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compatible = "spansion,m25p16", "jedec,spi-nor";
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spi-max-frequency = <40000000>;
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sandbox,filename = "spi.bin";
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};
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};
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Supported chips are W25Q16 (2MB), W25Q32 (4MB) and W25Q128 (16MB). Once
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U-Boot it started you can use 'sf' commands as normal. For example:
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$ dd if=/dev/zero of=spi.bin bs=1M count=2
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$ u-boot -T
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Since the SPI bus is fully implemented as well as the SPI flash connected to
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it, you can also use low-level SPI commands to access the flash. For example
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this reads the device ID from the emulated chip:
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=> sspi 0 32 9f
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SF: Detected m25p16 with page size 256 Bytes, erase size 64 KiB, total 2 MiB
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FF202015
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Simon Glass
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sjg@chromium.org
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7/11/2013
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Note that the sandbox SPI implementation was written by Mike Frysinger
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<vapier@gentoo.org>.
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