Quoting Sudeep Holla (2019-07-08 08:47:30) > CLOCK_PROTOCOL_ATTRIBUTES provides attributes to indicate the maximum > number of pending asynchronous clock rate changes supported by the > platform. If it's non-zero, then we should be able to use asynchronous > clock rate set for any clocks until the maximum limit is reached. > > Keeping the current count of pending asynchronous clock set rate > requests, we can decide if we can you asynchronous request for the
This last part of the sentence doesn't read properly. Please rewrite. > incoming/new request. > > Signed-off-by: Sudeep Holla <[email protected]> > --- > drivers/firmware/arm_scmi/clock.c | 21 ++++++++++++++++++--- > 1 file changed, 18 insertions(+), 3 deletions(-) > > diff --git a/drivers/firmware/arm_scmi/clock.c > b/drivers/firmware/arm_scmi/clock.c > index dd215bd11a58..70044b7c812e 100644 > --- a/drivers/firmware/arm_scmi/clock.c > +++ b/drivers/firmware/arm_scmi/clock.c > @@ -221,21 +222,35 @@ static int scmi_clock_rate_set(const struct scmi_handle > *handle, u32 clk_id, > u64 rate) > { > int ret; > + u32 flags = 0; > struct scmi_xfer *t; > struct scmi_clock_set_rate *cfg; > + struct clock_info *ci = handle->clk_priv; > > ret = scmi_xfer_get_init(handle, CLOCK_RATE_SET, SCMI_PROTOCOL_CLOCK, > sizeof(*cfg), 0, &t); > if (ret) > return ret; > > + if (ci->max_async_req) { > + if (atomic_inc_return(&ci->cur_async_req) < ci->max_async_req) > + flags |= CLOCK_SET_ASYNC; > + else > + atomic_dec(&ci->cur_async_req); Can this be combined with the atomic_dec() below and done after either transfer? > + } > + > cfg = t->tx.buf; > - cfg->flags = cpu_to_le32(0); > + cfg->flags = cpu_to_le32(flags); > cfg->id = cpu_to_le32(clk_id); > cfg->value_low = cpu_to_le32(rate & 0xffffffff); > cfg->value_high = cpu_to_le32(rate >> 32); > > - ret = scmi_do_xfer(handle, t); > + if (flags & CLOCK_SET_ASYNC) { > + ret = scmi_do_xfer_with_response(handle, t); > + atomic_dec(&ci->cur_async_req); > + } else { > + ret = scmi_do_xfer(handle, t); > + } I mean putting the atomic_dec() here. > > scmi_xfer_put(handle, t); > return ret;
