ron minnich wrote:
On Wed, Jun 4, 2008 at 9:46 AM, Marc Jones Marc.Jones@amd.com wrote:
ron minnich wrote:
This change adds some debug prints, and a comment warning to dts on cs5536.
Most importantly it fixes a simple programming error which made it so most of the sets on the USB were not doing anything. The bug is also in V2.
/* the /sizeof(u32) is to convert byte offsets into u32 offsets */ #define HCCPARAMS (0x08/sizeof(u32))
I don't understand this change. This is standard MMIO. The memory mapped registers are defined 0h, 04h, 08h, 0Ah...
You could *(bar + 08h) |= 1 << 9; or *(bar + 09h) |= 1 << 1;
This is an old C gotcha. Offsets are scaled by the pointer size. bar is a u32 *. So you see this: *(bar + HCCPARAMS)
And it's easy to think that it is this: *(bar + 0xc)
but actually, because bar is a u32 *, it will actually dereference this: *(bar + 0xc*4) i.e. the sizeof a u32 ...
It has to work this way, because when you do bar++, it increments bar by 4, not 1.
This is one of the reasons why, for mmio, we ought to be using structs.
thanks
ron
Doh! I see. It should be a byte pointer and then use the readl() abd writel() etc from io.h. I'll post a patch for v2 in a few minutes.
A struct for the entire device seems overkill for a couple of registers. Marc