[Nouveau] [RFC PATCH 18/29] clk: Only do partial reclocks as required

[Karol Herbst]

Signed-off-by: Karol Herbst <karolherbst at gmail.com>
---
 drm/nouveau/nvkm/subdev/clk/base.c  | 26 ++++++++++++++++++--------
 drm/nouveau/nvkm/subdev/volt/base.c |  3 +++
 2 files changed, 21 insertions(+), 8 deletions(-)

diff --git a/drm/nouveau/nvkm/subdev/clk/base.c b/drm/nouveau/nvkm/subdev/clk/base.c
index 72ca5e0c..a154a425 100644
--- a/drm/nouveau/nvkm/subdev/clk/base.c
+++ b/drm/nouveau/nvkm/subdev/clk/base.c
@@ -171,7 +171,7 @@ nvkm_cstate_prog(struct nvkm_clk *clk, struct nvkm_pstate *pstate, int cstatei)
 	struct nvkm_therm *therm = device->therm;
 	struct nvkm_volt *volt = device->volt;
 	struct nvkm_cstate *cstate;
-	int ret;
+	int ret = 0;
 
 	if (cstatei == NVKM_CLK_CSTATE_DEFAULT)
 		return 0;
@@ -183,6 +183,12 @@ nvkm_cstate_prog(struct nvkm_clk *clk, struct nvkm_pstate *pstate, int cstatei)
 		cstate = &pstate->base;
 	}
 
+	// if the cstate matches, just update the voltage
+	if (clk->cstate && clk->cstate == cstate)
+		return nvkm_volt_set_id(volt, clk->cstate->voltage,
+					clk->pstate->base.voltage, clk->temp,
+					0);
+
 	if (therm) {
 		ret = nvkm_therm_cstate(therm, pstate->fanspeed, +1);
 		if (ret && ret != -ENODEV) {
@@ -284,6 +290,11 @@ nvkm_pstate_prog(struct nvkm_clk *clk, int pstateid)
 	if (pstateid == NVKM_CLK_PSTATE_DEFAULT)
 		return 0;
 
+	if (clk->pstate && clk->pstate->pstate == pstateid) {
+		pstate = clk->pstate;
+		goto cstate;
+	}
+
 	list_for_each_entry(pstate, &clk->states, head) {
 		if (pstate->pstate == pstateid)
 			break;
@@ -308,6 +319,7 @@ nvkm_pstate_prog(struct nvkm_clk *clk, int pstateid)
 		ram->func->tidy(ram);
 	}
 
+cstate:
 	if (clk->throttled)
 		cstate = list_first_entry(&pstate->list, struct nvkm_cstate, head)->id;
 	else
@@ -321,7 +333,7 @@ nvkm_clk_update_work(struct work_struct *work)
 {
 	struct nvkm_clk *clk = container_of(work, typeof(*clk), work);
 	struct nvkm_subdev *subdev = &clk->subdev;
-	int pstate;
+	int pstate, ret;
 
 	if (!atomic_xchg(&clk->waiting, 0))
 		return;
@@ -341,12 +353,10 @@ nvkm_clk_update_work(struct work_struct *work)
 		   clk->pwrsrc, clk->ustate_ac, clk->ustate_dc,
 		   clk->astate, clk->exp_cstateid, clk->temp);
 
-	if (!clk->pstate || pstate != clk->pstate->pstate) {
-		int ret = nvkm_pstate_prog(clk, pstate);
-		if (ret) {
-			nvkm_error(subdev, "error setting pstate %d: %d\n",
-				   pstate, ret);
-		}
+	ret = nvkm_pstate_prog(clk, pstate);
+	if (ret) {
+		nvkm_error(subdev, "error setting pstate %d: %d\n",
+			   pstate, ret);
 	}
 
 	wake_up_all(&clk->wait);
diff --git a/drm/nouveau/nvkm/subdev/volt/base.c b/drm/nouveau/nvkm/subdev/volt/base.c
index e344901c..56a0f379 100644
--- a/drm/nouveau/nvkm/subdev/volt/base.c
+++ b/drm/nouveau/nvkm/subdev/volt/base.c
@@ -162,6 +162,9 @@ nvkm_volt_set_id(struct nvkm_volt *volt, u8 id, u8 min_id, u8 temp,
 {
 	int ret;
 
+	if (!volt)
+		return -ENODEV;
+
 	if (volt->func->set_id)
 		return volt->func->set_id(volt, id, condition);
 
-- 
2.14.1