69b921acae
The MPC8309 has a dedicated signal, SPISEL_BOOT, usually used as chip select for the flash device from which the bootloader is loaded. It is not an ordinary gpio, but is simply controlled via the SPI_CS register in the system configuration. To allow accessing such a spi slave, we need to teach fsl_spi_cs_control() how to control the SPISEL_BOOT signal. To distinguish the gpio-controlled slaves, continue to have those use chip_select values of 0..ngpios-1, and use chip_select == ngpios for the boot flash. I'm not too happy with all the ifdeffery, but it seems to be necessary for guarding the sysdev/fsl_soc.h and use of get_immrbase() (spi-fsl-lib.c already contains similar ifdeffery). Googling suggests that the MPC8306 is similar, with the SPI_CS register at the same offset. Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk> Signed-off-by: Mark Brown <broonie@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.