8148 add spi driver
http://blog.csdn.net/zouwen198317/article/details/8452209
http://e2e.ti.com/support/dsp/davinci_digital_media_processors/f/716/t/366275
http://e2e.ti.com/support/dsp/davinci_digital_media_processors/f/716/t/382636
http://e2e.ti.com/support/dsp/davinci_digital_media_processors/f/716/t/382636
http://processors.wiki.ti.com/index.php/TI81XX_PSP_McSPI_Driver_User_Guide
http://blog.csdn.net/droidphone/article/details/23932447
http://processors.wiki.ti.com/index.php/Category:DaVinci_Linux
http://processors.wiki.ti.com/index.php/DM814x_AM387x_PSP_User_Guide
http://processors.wiki.ti.com/index.php?title=TI81XX_PSP_McSPI_Driver_User_Guide&redirect=no
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