[Nouveau] [PATCH v4 27/37] clk: make pstate a pointer to nvkm_pstate

[Martin Peres]

On 18/04/16 22:14, Karol Herbst wrote:
> we will access the current set cstate at least every second and this safes us
saves
> some CPU cycles looking them up every second.
>
> Signed-off-by: Karol Herbst <nouveau at karolherbst.de>
> ---
>   drm/nouveau/include/nvkm/subdev/clk.h |  2 +-
>   drm/nouveau/nvkm/engine/device/ctrl.c |  5 ++++-
>   drm/nouveau/nvkm/subdev/clk/base.c    | 12 ++++++++----
>   drm/nouveau/nvkm/subdev/pmu/gk20a.c   | 23 +++++++----------------
>   4 files changed, 20 insertions(+), 22 deletions(-)
>
> diff --git a/drm/nouveau/include/nvkm/subdev/clk.h b/drm/nouveau/include/nvkm/subdev/clk.h
> index db52e65..4fb2c1b 100644
> --- a/drm/nouveau/include/nvkm/subdev/clk.h
> +++ b/drm/nouveau/include/nvkm/subdev/clk.h
> @@ -91,7 +91,7 @@ struct nvkm_clk {
>   
>   	struct nvkm_notify pwrsrc_ntfy;
>   	int pwrsrc;
> -	int pstate; /* current */
> +	struct nvkm_pstate *pstate; /* current */
>   	int ustate_ac; /* user-requested (-1 disabled, -2 perfmon) */
>   	int ustate_dc; /* user-requested (-1 disabled, -2 perfmon) */
>   	int astate; /* perfmon adjustment (base) */
> diff --git a/drm/nouveau/nvkm/engine/device/ctrl.c b/drm/nouveau/nvkm/engine/device/ctrl.c
> index 039e8a4..cb85266 100644
> --- a/drm/nouveau/nvkm/engine/device/ctrl.c
> +++ b/drm/nouveau/nvkm/engine/device/ctrl.c
> @@ -52,7 +52,10 @@ nvkm_control_mthd_pstate_info(struct nvkm_control *ctrl, void *data, u32 size)
>   		args->v0.ustate_ac = clk->ustate_ac;
>   		args->v0.ustate_dc = clk->ustate_dc;
>   		args->v0.pwrsrc = clk->pwrsrc;
> -		args->v0.pstate = clk->pstate;
> +		if (clk->pstate)
> +			args->v0.pstate = clk->pstate->pstate;
> +		else
> +			args->v0.pstate = -1;
>   	} else {
>   		args->v0.count = 0;
>   		args->v0.ustate_ac = NVIF_CONTROL_PSTATE_INFO_V0_USTATE_DISABLE;
> diff --git a/drm/nouveau/nvkm/subdev/clk/base.c b/drm/nouveau/nvkm/subdev/clk/base.c
> index 3867ab7..762dfe2 100644
> --- a/drm/nouveau/nvkm/subdev/clk/base.c
> +++ b/drm/nouveau/nvkm/subdev/clk/base.c
> @@ -288,7 +288,7 @@ nvkm_pstate_prog(struct nvkm_clk *clk, int pstatei)
>   	}
>   
>   	nvkm_debug(subdev, "setting performance state %d\n", pstatei);
> -	clk->pstate = pstatei;
> +	clk->pstate = pstate;
>   
>   	nvkm_pcie_set_link(pci, pstate->pcie_speed, pstate->pcie_width);
>   
> @@ -317,15 +317,19 @@ nvkm_clk_update_work(struct work_struct *work)
>   		return;
>   	clk->pwrsrc = power_supply_is_system_supplied();
>   
> +	if (clk->pstate)
> +		pstate = clk->pstate->pstate;
> +	else
> +		pstate = -1;
>   	nvkm_trace(subdev, "P %d PWR %d U(AC) %d U(DC) %d A %d\n",
> -		   clk->pstate, clk->pwrsrc, clk->ustate_ac, clk->ustate_dc,
> +		   pstate, clk->pwrsrc, clk->ustate_ac, clk->ustate_dc,
>   		   clk->astate);
>   
>   	pstate = clk->pwrsrc ? clk->ustate_ac : clk->ustate_dc;
>   	if (clk->state_nr && pstate != -1) {
>   		pstate = (pstate < 0) ? clk->astate : pstate;
>   	} else {
> -		pstate = clk->pstate = -1;
> +		pstate = -1;

Isn't "clk->pstate = NULL;" missing here? Why did you change this code otherwise?

>   	}
>   
>   	nvkm_trace(subdev, "-> %d\n", pstate);
> @@ -609,7 +613,7 @@ nvkm_clk_init(struct nvkm_subdev *subdev)
>   		return clk->func->init(clk);
>   
>   	clk->astate = clk->state_nr - 1;
> -	clk->pstate = -1;
> +	clk->pstate = NULL;
>   	nvkm_clk_update(clk, true);
>   	return 0;
>   }
> diff --git a/drm/nouveau/nvkm/subdev/pmu/gk20a.c b/drm/nouveau/nvkm/subdev/pmu/gk20a.c
> index f996d90..6f0d290 100644
> --- a/drm/nouveau/nvkm/subdev/pmu/gk20a.c
> +++ b/drm/nouveau/nvkm/subdev/pmu/gk20a.c
> @@ -57,24 +57,21 @@ gk20a_pmu_dvfs_target(struct gk20a_pmu *pmu, int *state)
>   }
>   
>   static int
> -gk20a_pmu_dvfs_get_cur_state(struct gk20a_pmu *pmu, int *state)
> -{
> -	struct nvkm_clk *clk = pmu->base.subdev.device->clk;
> -
> -	*state = clk->pstate;
> -	return 0;
> -}
> -
> -static int
>   gk20a_pmu_dvfs_get_target_state(struct gk20a_pmu *pmu,
>   				int *state, int load)
>   {
>   	struct gk20a_pmu_dvfs_data *data = pmu->data;
>   	struct nvkm_clk *clk = pmu->base.subdev.device->clk;
> +	struct nvkm_pstate *pstate = clk->pstate;
>   	int cur_level, level;
>   
> +	if (!pstate) {
> +		*state = 0;
> +		return 1;
> +	}
> +
>   	/* For GK20A, the performance level is directly mapped to pstate */
> -	level = cur_level = clk->pstate;
> +	level = cur_level = clk->pstate->pstate;
>   
>   	if (load > data->p_load_max) {
>   		level = min(clk->state_nr - 1, level + (clk->state_nr / 3));
> @@ -150,12 +147,6 @@ gk20a_pmu_dvfs_work(struct nvkm_alarm *alarm)
>   	nvkm_trace(subdev, "utilization = %d %%, avg_load = %d %%\n",
>   		   utilization, data->avg_load);
>   
> -	ret = gk20a_pmu_dvfs_get_cur_state(pmu, &state);
> -	if (ret) {
> -		nvkm_warn(subdev, "failed to get current state\n");
> -		goto resched;
> -	}
> -
>   	if (gk20a_pmu_dvfs_get_target_state(pmu, &state, data->avg_load)) {
>   		nvkm_trace(subdev, "set new state to %d\n", state);
>   		gk20a_pmu_dvfs_target(pmu, &state);