lkml.org 
[lkml]   [2020]   [Jan]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    From
    SubjectRe: [PATCH v2 1/2] powerpc/hw_breakpoints: Rewrite 8xx breakpoints to allow any address range size.
    Date
    On Tue, 2019-11-26 at 17:43:29 UTC, Christophe Leroy wrote:
    > Unlike standard powerpc, Powerpc 8xx doesn't have SPRN_DABR, but
    > it has a breakpoint support based on a set of comparators which
    > allow more flexibility.
    >
    > Commit 4ad8622dc548 ("powerpc/8xx: Implement hw_breakpoint")
    > implemented breakpoints by emulating the DABR behaviour. It did
    > this by setting one comparator the match 4 bytes at breakpoint address
    > and the other comparator to match 4 bytes at breakpoint address + 4.
    >
    > Rewrite 8xx hw_breakpoint to make breakpoints match all addresses
    > defined by the breakpoint address and length by making full use of
    > comparators.
    >
    > Now, comparator E is set to match any address greater than breakpoint
    > address minus one. Comparator F is set to match any address lower than
    > breakpoint address plus breakpoint length. Addresses are aligned
    > to 32 bits.
    >
    > When the breakpoint range starts at address 0, the breakpoint is set
    > to match comparator F only. When the breakpoint range end at address
    > 0xffffffff, the breakpoint is set to match comparator E only.
    > Otherwise the breakpoint is set to match comparator E and F.
    >
    > At the same time, use registers bit names instead of hardcoded values.
    >
    > Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
    > Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>

    Series applied to powerpc next, thanks.

    https://git.kernel.org/powerpc/c/39413ae009674c6ba745850515b551bbb9d6374b

    cheers

    \
     
     \ /
      Last update: 2020-01-29 06:17    [W:5.740 / U:0.008 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site