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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using the --spi_sf paramter when starting U-Boot.
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For example:
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$ make O=sandbox sandbox_config
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$ make O=sandbox
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$ ./sandbox/u-boot --spi_sf 0:0:W25Q128:b/chromeos_peach/out/image.bin
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The four parameters to spi_sf are:
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SPI bus number (typically 0)
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SPI chip select number (typically 0)
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SPI chip to emulate
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File containing emulated data
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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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$ ./b/sandbox/u-boot --spi_sf 0:0:W25Q128:b/chromeos_peach/out/image.bin \
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-c "sf probe; sf test 0 100000; sf read 0 1000 1000; \
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sf erase 1000 1000; sf write 0 1000 1000"
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U-Boot 2013.10-00237-gd4e0fdb (Nov 07 2013 - 20:08:15)
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DRAM: 128 MiB
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Using default environment
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In: serial
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Out: serial
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Err: serial
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SF: Detected W25Q128BV with page size 256 Bytes, erase size 4 KiB, total 16 MiB
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SPI flash test:
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0 erase: 1 ticks, 1024000 KiB/s 8192.000 Mbps
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1 check: 2 ticks, 512000 KiB/s 4096.000 Mbps
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2 write: 6 ticks, 170666 KiB/s 1365.328 Mbps
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3 read: 0 ticks, 1048576000 KiB/s -201326.-592 Mbps
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Test passed
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0 erase: 1 ticks, 1024000 KiB/s 8192.000 Mbps
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1 check: 2 ticks, 512000 KiB/s 4096.000 Mbps
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2 write: 6 ticks, 170666 KiB/s 1365.328 Mbps
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3 read: 0 ticks, 1048576000 KiB/s -201326.-592 Mbps
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SF: 4096 bytes @ 0x1000 Read: OK
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SF: 4096 bytes @ 0x1000 Erased: OK
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SF: 4096 bytes @ 0x1000 Written: OK
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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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FFEF4018
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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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