1 files changed, 29 insertions, 17 deletions

diff --git a/drivers/gpu/nvgpu/clk/clk_arb.c b/drivers/gpu/nvgpu/clk/clk_arb.c
index 1b974d17..f3d6cfab 100644
--- a/drivers/gpu/nvgpu/clk/clk_arb.c
+++ b/drivers/gpu/nvgpu/clk/clk_arb.c
@@ -83,6 +83,7 @@ struct nvgpu_clk_arb {
         struct llist_head requests;
 
         struct gk20a *g;
+        int status;
 
         struct nvgpu_clk_arb_target actual_pool[2];
         struct nvgpu_clk_arb_target *actual;
@@ -269,7 +270,8 @@ int nvgpu_clk_arb_init_arbiter(struct gk20a *g)
                         atomic_read(&arb->req_nr));
         } while (!atomic_read(&arb->req_nr));
 
-        return 0;
+
+        return arb->status;
 
 init_fail:
 
@@ -533,6 +535,7 @@ static int nvgpu_clk_arb_update_vf_table(struct nvgpu_clk_arb *arb)
                         clk_cur = table->mclk_points[j].mhz;
                         j++;
                         num_points++;
+
                 }
         }
         table->mclk_num_points = num_points;
@@ -605,7 +608,7 @@ static void nvgpu_clk_arb_run_vf_table_cb(struct work_struct *work)
         err = clk_vf_point_cache(g);
         if (err) {
                 gk20a_err(dev_from_gk20a(g),
-                        "failed to get GPC2CLK SRAM voltage");
+                        "failed to cache VF table");
                 return;
         }
         nvgpu_clk_arb_update_vf_table(arb);
@@ -625,7 +628,7 @@ static void nvgpu_clk_arb_run_arbiter_cb(struct work_struct *work)
         u32 voltuv, voltuv_sram;
         bool mclk_set, gpc2clk_set;
 
-        int status;
+        int status = 0;
 
         /* Temporary variables for checking target frequency */
         u16 gpc2clk_target, mclk_target;
@@ -742,15 +745,21 @@ static void nvgpu_clk_arb_run_arbiter_cb(struct work_struct *work)
         actual->gpc2clk = gpc2clk_target;
         actual->mclk = mclk_target;
         arb->voltuv_actual = voltuv;
+        arb->status = status;
 
         /* Make changes visible to other threads */
         smp_wmb();
         xchg(&arb->actual, actual);
 
+        /* status must be visible before atomic inc */
+        smp_wmb();
         atomic_inc(&arb->req_nr);
 
         wake_up_interruptible(&arb->request_wq);
 
+        if (status < 0)
+                gk20a_err(dev_from_gk20a(g),
+                        "Error in arbiter update");
 
 #ifdef CONFIG_DEBUG_FS
         g->ops.read_ptimer(g, &t1);
@@ -1016,20 +1025,23 @@ static void nvgpu_clk_arb_find_vf_point(struct nvgpu_clk_arb *arb,
         struct nvgpu_clk_vf_table *table;
         u32 index;
 
-        gpc2clk_target = *gpc2clk;
-        mclk_target = *mclk;
-        gpc2clk_voltuv = 0;
-        gpc2clk_voltuv_sram = 0;
-        mclk_voltuv = 0;
-        mclk_voltuv_sram = 0;
-
         do {
+                gpc2clk_target = *gpc2clk;
+                mclk_target = *mclk;
+                gpc2clk_voltuv = 0;
+                gpc2clk_voltuv_sram = 0;
+                mclk_voltuv = 0;
+                mclk_voltuv_sram = 0;
+
                 table = ACCESS_ONCE(arb->current_vf_table);
                 /* pointer to table can be updated by callback */
                 smp_rmb();
 
                 if (!table)
                         continue;
+                if ((!table->gpc2clk_num_points) || (!table->mclk_num_points))
+                        goto find_exit;
+
                 /* round up the freq requests */
                 for (index = 0; index < table->gpc2clk_num_points; index++) {
                         if (table->gpc2clk_points[index].mhz >=
@@ -1045,10 +1057,10 @@ static void nvgpu_clk_arb_find_vf_point(struct nvgpu_clk_arb *arb,
                 }
 
                 if (index == table->gpc2clk_num_points) {
-                        gpc2clk_target = table->gpc2clk_points[index].mhz;
-                        gpc2clk_voltuv = table->gpc2clk_points[index].uvolt;
+                        gpc2clk_target = table->gpc2clk_points[index-1].mhz;
+                        gpc2clk_voltuv = table->gpc2clk_points[index-1].uvolt;
                         gpc2clk_voltuv_sram =
-                                table->gpc2clk_points[index].uvolt_sram;
+                                table->gpc2clk_points[index-1].uvolt_sram;
                 }
 
                 for (index = 0; index < table->mclk_num_points; index++) {
@@ -1061,14 +1073,15 @@ static void nvgpu_clk_arb_find_vf_point(struct nvgpu_clk_arb *arb,
                         }
                 }
                 if (index == table->mclk_num_points) {
-                        mclk_target = table->mclk_points[index].mhz;
-                        mclk_voltuv = table->mclk_points[index].uvolt;
+                        mclk_target = table->mclk_points[index-1].mhz;
+                        mclk_voltuv = table->mclk_points[index-1].uvolt;
                         mclk_voltuv_sram =
-                                table->mclk_points[index].uvolt_sram;
+                                table->mclk_points[index-1].uvolt_sram;
                 }
         } while (!table ||
                 (ACCESS_ONCE(arb->current_vf_table) != table));
 
+find_exit:
         *voltuv = gpc2clk_voltuv > mclk_voltuv ? gpc2clk_voltuv : mclk_voltuv;
         *voltuv_sram = gpc2clk_voltuv_sram > mclk_voltuv_sram ?
                 gpc2clk_voltuv_sram : mclk_voltuv_sram;
@@ -1136,7 +1149,6 @@ static int nvgpu_clk_arb_change_vf_point(struct gk20a *g, u16 gpc2clk_target,
                 status = clk_program_fll_clks(g, &fllclk);
                 if (status < 0)
                         return status;
-
         }
 
         return 0;