On Mon, 11 Aug 2008, Wolfgang Denk wrote:
Dear Guennadi Liakhovetski,
In message Pine.LNX.4.64.0808111737330.30591@axis700.grange you wrote:
As I remarked in the opening email to the SMDK6400 patch-series, I've got a strange problem, I cannot understand.
What exactly is your problem?
Right, sorry, the problem is simple: it doesn't work with the byte access.
which converts all accesses to the structure to 8-bit... Ideas? Toolchain eldk-4.1. U-Boot from nand/testing git with the patches I just sent to the list, configured for smdk6400_config.
Note that you did not exactly ask a question, you just describe your observations so we have to guess what might be puzzeling you. I think that some people with more ARM experience than me will simply not understand what you are asking about, because they are used to GCC turning perfectly valid looking 32 bit accesses into a sequence of four 8 bit accesses.
They consider this "normal".
I cannot think of any such examples... I know access-types can be changed on the hardware, say, on a 16-bit bus a 32-bit access can be split into two 16-bit accesses, but I currently cannot think of any examples of the compiler doing such things. But, I think, I can imagine _why_ the compiler might decide to do that - it cannot guarantee, that the structure is 32-bit aligned, so, it is opting for the "safe" variant... So, the question is: is the compiler right and the c-code was wrong, or the other way round?
Thanks Guennadi --- Guennadi Liakhovetski, Ph.D.
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