Re: [PATCH v3 13/18] target/arm: Update contiguous first-fault and no-fault loads

2020-04-28 Thread Richard Henderson
On 4/27/20 11:38 AM, Peter Maydell wrote: > I would suggest something like: > > + * From this point on, all memory operations are MemSingleNF. > + * > + * Per the MemSingleNF pseudocode, a no-fault load from Device memory > + * must not actually hit the bus -- it returns (UNKNOWN,

Re: [PATCH v3 13/18] target/arm: Update contiguous first-fault and no-fault loads

2020-04-27 Thread Peter Maydell
On Mon, 27 Apr 2020 at 17:45, Richard Henderson wrote: > We *can* indicate fault from MemSingleNF for any reason whatsoever, or no > reason whatsoever. > > > // Implementation may suppress NF load for any reason > > if ConstrainUnpredictableBool(Unpredictable_NONFAULT) then > > return (bits(8*si

Re: [PATCH v3 13/18] target/arm: Update contiguous first-fault and no-fault loads

2020-04-27 Thread Richard Henderson
On 4/27/20 9:32 AM, Peter Maydell wrote: + * From this point on, all memory operations are MemSingleNF. + * + * Per the MemSingleNF pseudocode, a no-fault load from Device memory + * must not actually hit the bus -- it returns (UNKNOWN, FAULT) instead.

Re: [PATCH v3 13/18] target/arm: Update contiguous first-fault and no-fault loads

2020-04-27 Thread Peter Maydell
On Mon, 27 Apr 2020 at 17:16, Richard Henderson wrote: > > On 4/27/20 4:03 AM, Peter Maydell wrote: > > On Wed, 22 Apr 2020 at 05:33, Richard Henderson > > wrote: > >> > >> With sve_cont_ldst_pages, the differences between first-fault and no-fault > >> are minimal, so unify the routines. With cp

Re: [PATCH v3 13/18] target/arm: Update contiguous first-fault and no-fault loads

2020-04-27 Thread Richard Henderson
On 4/27/20 4:03 AM, Peter Maydell wrote: > On Wed, 22 Apr 2020 at 05:33, Richard Henderson > wrote: >> >> With sve_cont_ldst_pages, the differences between first-fault and no-fault >> are minimal, so unify the routines. With cpu_probe_watchpoint, we are able >> to make progress through pages with

Re: [PATCH v3 13/18] target/arm: Update contiguous first-fault and no-fault loads

2020-04-27 Thread Peter Maydell
On Wed, 22 Apr 2020 at 05:33, Richard Henderson wrote: > > With sve_cont_ldst_pages, the differences between first-fault and no-fault > are minimal, so unify the routines. With cpu_probe_watchpoint, we are able > to make progress through pages with TLB_WATCHPOINT set when the watchpoint > does no

[PATCH v3 13/18] target/arm: Update contiguous first-fault and no-fault loads

2020-04-21 Thread Richard Henderson
With sve_cont_ldst_pages, the differences between first-fault and no-fault are minimal, so unify the routines. With cpu_probe_watchpoint, we are able to make progress through pages with TLB_WATCHPOINT set when the watchpoint does not actually fire. Signed-off-by: Richard Henderson --- target/ar