>>>>> "Peter" == Peter Allworth <linsol at zeta.org.au> writes:
Peter> duncanp at research.canon.com.au wrote: >> Dan, >> >> On 1 Feb, Dan Malek wrote: > I have already incorporated most of >> these into 2.3.xx > kernel, and a 2.2.13 version that I will update >> as a tar file > on a server. >> >> would you mind posting a diff against the current 2.2.13 kernel on >> the ftp server when you do this as well? we've got a kernel in CVS >> here (i imagine plently of others are doing this too), and it would >> be easier for us if we can patch it. >> >> Dunk. Peter> Dunk, Peter> If you need the MMU patches straight-away, I've put them on Peter> http://www.zeta.org.au/~linsol Peter> They only work against cllf-2.2.13 for now. Marcus Sundberg has Peter> sent me a revised patch which should work for other 2.2 kernels Peter> (caveat emptor). I'll try to add that asap. Peter and Duncan, The 2.2.13 patch you posted was slightly (but critically) wrong, if I'm not mistaken. The value updated in memory was not reloaded into r21 which is where the code below this snipped expects to find the value. This patch should do the trick. At least my kernel seems to work. --- head.S.orig Sat Oct 23 00:18:03 1999 +++ head.S Tue Feb 8 10:34:02 2000 @@ -1024,6 +1024,18 @@ ori r21, r21, 1 /* Set valid bit in physical L2 page */ mtspr MD_TWC, r21 /* Load pte table base address */ mfspr r21, MD_TWC /* ....and get the pte address */ + lwz r20, 0(r21) /* Get the pte */ + andi. r20, r20, _PAGE_PRESENT /* Set cr0 if it's invalid */ + beq 4f /* Skip update if invalid */ + mfspr r20, DSISR /* Check for store op */ + andis. r20, r20, 0x0200 /* If set, indicates store */ + lwz r20, 0(r21) /* Get the pte again */ + beq 3f + ori r20, r20, _PAGE_DIRTY|_PAGE_HWWRITE /* Set the dirty flags */ +3: + ori r20, r20, _PAGE_ACCESSED /* Set the accessed flag */ + stw r20, 0(r21) /* Update the pte */ +4: lwz r21, 0(r21) /* Get the pte */ /* Set four subpage valid bits (24, 25, 26, and 27). An alternative and slighly faster implementation might be to skip the _PAGE_PRESENT check. Any reason something like this wouldn't work? ori r21, r21, 1 /* Set valid bit in physical L2 page */ mtspr MD_TWC, r21 /* Load pte table base address */ mfspr r21, MD_TWC /* ....and get the pte address */ mfspr r20, DSISR /* Check for store op */ andis. r20, r20, 0x0200 /* If set, indicates store */ lwz r20, 0(r21) /* Get the pte again */ beq 3f ori r20, r20, _PAGE_DIRTY|_PAGE_HWWRITE /* Set the dirty flags */ 3: ori r20, r20, _PAGE_ACCESSED /* Set the accessed flag */ stw r20, 0(r21) /* Update the pte */ mr r21, r20 /* Get the pte */ Cheers, Jesper ** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/
