1 Sandbox SPI/SPI Flash Implementation 2 ==================================== 3 4 U-Boot supports SPI and SPI flash emulation in sandbox. This must be enabled 5 using the --spi_sf paramter when starting U-Boot. 6 7 For example: 8 9 $ make O=sandbox sandbox_config 10 $ make O=sandbox 11 $ ./sandbox/u-boot --spi_sf 0:0:W25Q128:b/chromeos_peach/out/image.bin 12 13 The four parameters to spi_sf are: 14 15 SPI bus number (typically 0) 16 SPI chip select number (typically 0) 17 SPI chip to emulate 18 File containing emulated data 19 20 Supported chips are W25Q16 (2MB), W25Q32 (4MB) and W25Q128 (16MB). Once 21 U-Boot it started you can use 'sf' commands as normal. For example: 22 23 $ ./b/sandbox/u-boot --spi_sf 0:0:W25Q128:b/chromeos_peach/out/image.bin \ 24 -c "sf probe; sf test 0 100000; sf read 0 1000 1000; \ 25 sf erase 1000 1000; sf write 0 1000 1000" 26 27 28 U-Boot 2013.10-00237-gd4e0fdb (Nov 07 2013 - 20:08:15) 29 30 DRAM: 128 MiB 31 Using default environment 32 33 In: serial 34 Out: serial 35 Err: serial 36 SF: Detected W25Q128BV with page size 256 Bytes, erase size 4 KiB, total 16 MiB 37 SPI flash test: 38 0 erase: 1 ticks, 1024000 KiB/s 8192.000 Mbps 39 1 check: 2 ticks, 512000 KiB/s 4096.000 Mbps 40 2 write: 6 ticks, 170666 KiB/s 1365.328 Mbps 41 3 read: 0 ticks, 1048576000 KiB/s -201326.-592 Mbps 42 Test passed 43 0 erase: 1 ticks, 1024000 KiB/s 8192.000 Mbps 44 1 check: 2 ticks, 512000 KiB/s 4096.000 Mbps 45 2 write: 6 ticks, 170666 KiB/s 1365.328 Mbps 46 3 read: 0 ticks, 1048576000 KiB/s -201326.-592 Mbps 47 SF: 4096 bytes @ 0x1000 Read: OK 48 SF: 4096 bytes @ 0x1000 Erased: OK 49 SF: 4096 bytes @ 0x1000 Written: OK 50 51 52 Since the SPI bus is fully implemented as well as the SPI flash connected to 53 it, you can also use low-level SPI commands to access the flash. For example 54 this reads the device ID from the emulated chip: 55 56 => sspi 0 32 9f 57 FFEF4018 58 59 60 Simon Glass 61 sjg (a] chromium.org 62 7/11/2013 63 Note that the sandbox SPI implementation was written by Mike Frysinger 64 <vapier (a] gentoo.org>. 65
