Let's cc the suitable people. On Tue, 28 Apr 2009 18:23:42 -0700 "Jeff Haran" <[email protected]> wrote:
> Hi, > > Recent versions of this function contain the following snippets: > > if (err_detect & DDR_EDE_SBE) > edac_mc_handle_ce(mci, pfn, err_addr & PAGE_MASK, > syndrome, row_index, 0, mci->ctl_name); > > if (err_detect & DDR_EDE_MBE) > edac_mc_handle_ue(mci, pfn, err_addr & PAGE_MASK, > row_index, mci->ctl_name); > > I am pretty sure the references to PAGE_MASK should be proceeded by a > tilda, as in: > > if (err_detect & DDR_EDE_SBE) > edac_mc_handle_ce(mci, pfn, err_addr & ~PAGE_MASK, > syndrome, row_index, 0, mci->ctl_name); > > if (err_detect & DDR_EDE_MBE) > edac_mc_handle_ue(mci, pfn, err_addr & ~PAGE_MASK, > row_index, mci->ctl_name); > Could well be. PAGE_MASK is very easy to get wrong. I've _never_ trusted my own memory of it and I always have to go back to the definition when reviewing code :( > Much as I would like to submit a tested patch like the rest of the > world, I find myself in the situation where the only Freescale target > system I have to test on is running a 3 year old kernel (2.6.14), which > preceeds the introduction of EDAC driver support, at least for > Freescale. So the best I can do is borrow from the new EDAC driver and > backport it to the old kernel. > > But I have learned a few things in this process and can thus share what > I've learned as it may be of help to the EDAC driver developers: > > 1) Before you read the Freescale 8548 CAPTURE_ADDRESS register, you want > to read CAPTURE_ATTRIBUTES first and make sure the VLD bit (least > significant bit in the register) is set or else the data in > CAPTURE_ADDRESS may not be yet valid. > > 2) When you are done scrubbing the memory with the single bit error, you > want to write 0 to CAPTURE_ATTRIBUTES so as to clear VLD and thus setup > the ECC capture logic to capture the next single bit error. > _______________________________________________ Linuxppc-dev mailing list [email protected] https://ozlabs.org/mailman/listinfo/linuxppc-dev
