On Mon, 2014-02-24 at 14:44 +0800, Tang Yuantian-B29983 wrote: > On 2014/2/18 ζζδΊ 3:18, Scott Wood wrote: > > On Sun, 2014-02-16 at 21:35 -0600, Tang Yuantian-B29983 wrote: > >>> -----Original Message----- > >>> From: Wood Scott-B07421 > >>> To: Tang Yuantian-B29983 > >>> Cc: Sun York-R58495; Li Yang-Leo-R58472; u-boot@lists.denx.de; Kushwaha > >>> Prabhakar-B32579; Jin Zhengxiong-R64188 > >>> Subject: Re: [U-Boot,2/3] mpc85xx: Add deep sleep framework support > >>> > >>> On Thu, 2014-02-13 at 02:12 -0600, Tang Yuantian-B29983 wrote: > >>>>> Use an I/O accessor. > >>>> In_be64?? No such function. > >>> Why do you need in_be64() rather than two in_be32()s? > >>> > >> Avoid ECC error. Although, according to my test, in_be32() works too. > > Why would you get an ECC error? > > > > -Scott > DDR operation is always in 64bits. if writing a 32bits to memory, you > need to > read a 32bits first, and combine it to form a 64bits. when the new > 64bits is written > to memory, ECC occurs. > I was required to do so by hardware team.
U-Boot on PPC is a 32-bit binary (even on 64-bit hardware), so the compiler is already turning that into two 32-bit writes. -Scott _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot