Hi, my platform (PMC-Sierra Yosemite in big endian mode), like many others, uses ioremap() to map device registers, such as the RM9000's OCD registers. To access those registers, the return value of ioremap() is casted to a suitable pointer type and dereferenced. This of course works, but the return value of ioremap() is documented not to be a directly dereferenceable pointer value, and accesses to ioremapped addresses should be performed using the readx/writex APIs. I therefore decided to straighten this out and use those APIs throughout, but that did not work. The platform defines 'CONFIG_SWAP_IO_SPACE=y', which causes all accesses through readx/writex to be byte-swapped. That is not really appropriate, as the registers are in big endian order. I therefore tried to change that setting in yosemite_defconfig, only to find that every time I do 'make oldconfig' it returns to its original value of 'y'. So here are my questions: 1. Am I right to conclude that the platform configuration should not set CONFIG_SWAP_IO_SPACE, or am I missing something? 2. What is the mechanism that causes that setting to always revert to enabled when doing 'make oldconfig'? How do I avoid that? thanks, Thomas -- -------------------------------------------------- Thomas Koeller, Software Development Basler Vision Technologies thomas dot koeller at baslerweb dot com http://www.baslerweb.com ==============================
