Hi Tom, On Tue, 5 Feb 2013 09:58:52 -0500, Tom Rini <[email protected]> wrote:
> On Mon, Feb 04, 2013 at 03:19:56PM +0100, Albert ARIBAUD wrote: > > Hi Nikita, > > > > On Mon, 04 Feb 2013 14:37:06 +0200, Nikita Kiryanov > > <[email protected]> wrote: > > > > > Hi Albert, > > > > > > On 02/04/2013 01:57 PM, Albert ARIBAUD wrote: > > > > > > > > IIRC, you has submitted a fix so that BMP loads would result in > > > > correctly aligned fields and thus no need for accessors. Why this > > > > change of mind? > > > > > > > > > > I did mention that I consider that fix as temporary. I believe this fix > > > is better because it addresses the issue everywhere and does so in a > > > more maintainable way (does not require the address fix to be duplicated > > > everywhere there is a problem). > > > > I actually like the new fix less, as it adds an API where there is no > > need of one -- it's not like the implementation of BMP is at risk of > > changing. What is the problem in fixing the load address at load time > > and then passing this fixed address around? > > OK, so I'm wondering. Isn't this an example of where our idea that > unaligned accesses are a software problem to fix, rather than an area to > let the hardware fixup for us, when able, is wrong? > > In other words, a real life example of why we should go with > -munaligned-access being set for v7, set the HW bit and let things go? I feel this is addressed to me. :) And no, I don't think the BMP issue should be solved by relaxing HW constraints. BMP is not a HW-enforced or protocol format. Anyway, as I said, even if we really could not avoid misaligned fields (and we know at least two ways we could), then the solution would not be to flip a general HW switch controlling all accesses, since only the BMP accesses are a problem! We could just make sure we access the poorly aligned fields through dedicated unaligned accessors, e.g. readl_u(&field) / writel_u(&field). Amicalement, -- Albert. _______________________________________________ U-Boot mailing list [email protected] http://lists.denx.de/mailman/listinfo/u-boot
