Re: [RFC PATCH 02/10] ppc/pnv: Move timebase state into PnvCore

[Nicholas Piggin]

On Tue May 28, 2024 at 5:52 PM AEST, Cédric Le Goater wrote:
> On 5/28/24 08:28, Harsh Prateek Bora wrote:
> > 
> > 
> > On 5/26/24 17:56, Nicholas Piggin wrote:
> >> The timebase state machine is per per-core state and can be driven
> >> by any thread in the core. It is currently implemented as a hack
> >> where the state is in a CPU structure and only thread 0's state is
> >> accessed by the chiptod, which limits programming the timebase
> >> side of the state machine to thread 0 of a core.
> >>
> >> Move the state out into PnvCore and share it among all threads.
> >>
> >> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
> >> ---
> >>   include/hw/ppc/pnv_core.h    | 17 ++++++++++++
> >>   target/ppc/cpu.h             | 20 --------------
> >>   hw/ppc/pnv_chiptod.c         |  6 ++--
> >>   target/ppc/timebase_helper.c | 53 ++++++++++++++++++++----------------
> >>   4 files changed, 49 insertions(+), 47 deletions(-)
> >>
> >> diff --git a/include/hw/ppc/pnv_core.h b/include/hw/ppc/pnv_core.h
> >> index 30c1e5b1a3..f434c71547 100644
> >> --- a/include/hw/ppc/pnv_core.h
> >> +++ b/include/hw/ppc/pnv_core.h
> >> @@ -25,6 +25,20 @@
> >>   #include "hw/ppc/pnv.h"
> >>   #include "qom/object.h"
> >> +/* ChipTOD and TimeBase State Machine */
> >> +struct pnv_tod_tbst {
> >> +    int tb_ready_for_tod; /* core TB ready to receive TOD from chiptod */
> >> +    int tod_sent_to_tb;   /* chiptod sent TOD to the core TB */
> >> +
> >> +    /*
> >> +     * "Timers" for async TBST events are simulated by mfTFAC because TFAC
> >> +     * is polled for such events. These are just used to ensure firmware
> >> +     * performs the polling at least a few times.
> >> +     */
> >> +    int tb_state_timer;
> >> +    int tb_sync_pulse_timer;
> >> +};
> >> +
> >>   #define TYPE_PNV_CORE "powernv-cpu-core"
> >>   OBJECT_DECLARE_TYPE(PnvCore, PnvCoreClass,
> >>                       PNV_CORE)
> >> @@ -38,6 +52,9 @@ struct PnvCore {
> >>       uint32_t pir;
> >>       uint32_t hwid;
> >>       uint64_t hrmor;
> >> +
> >> +    struct pnv_tod_tbst pnv_tod_tbst;
> >> +
> > 
> > Now that it is part of struct PnvCore itself, we can drop pnv_ prefix
> > and just call the member variable as tod_tbst ?
>
> yes and rename pnv_tod_tbst using CamelCase please.

Okay will do. That'll look nicer.

Thanks,
Nick