1 files changed, 20 insertions, 3 deletions

diff --git a/drivers/gpu/nvgpu/gm20b/clk_gm20b.c b/drivers/gpu/nvgpu/gm20b/clk_gm20b.c
index 8dfc5636..b0e72552 100644
--- a/drivers/gpu/nvgpu/gm20b/clk_gm20b.c
+++ b/drivers/gpu/nvgpu/gm20b/clk_gm20b.c
@@ -454,7 +454,7 @@ static void clk_setup_dvfs_detection(struct gk20a *g, struct pll *gpll)
 /* Enable NA/DVFS mode */
 static int clk_enbale_pll_dvfs(struct gk20a *g)
 {
-        u32 data;
+        u32 data, cfg;
         int delay = gpc_pll_params.iddq_exit_delay; /* iddq & calib delay */
         struct pll_parms *p = &gpc_pll_params;
         bool calibrated = p->uvdet_slope && p->uvdet_offs;
@@ -509,6 +509,14 @@ static int clk_enbale_pll_dvfs(struct gk20a *g)
         data |= trim_sys_gpcpll_dvfs1_en_dfs_cal_m();
         gk20a_writel(g, trim_sys_gpcpll_dvfs1_r(), data);
 
+        /* C1 PLL must be enabled to read internal calibration results */
+        if (g->clk.gpc_pll.id == GM20B_GPC_PLL_C1) {
+                cfg = gk20a_readl(g, trim_sys_gpcpll_cfg_r());
+                cfg = set_field(cfg, trim_sys_gpcpll_cfg_enable_m(),
+                                trim_sys_gpcpll_cfg_enable_yes_f());
+                gk20a_writel(g, trim_sys_gpcpll_cfg_r(), cfg);
+        }
+
         /* Wait for internal calibration done (spec < 2us). */
         do {
                 data = gk20a_readl(g, trim_sys_gpcpll_dvfs1_r());
@@ -518,13 +526,22 @@ static int clk_enbale_pll_dvfs(struct gk20a *g)
                 delay--;
         } while (delay > 0);
 
+        /* Read calibration results */
+        data = gk20a_readl(g, trim_sys_gpcpll_cfg3_r());
+        data = trim_sys_gpcpll_cfg3_dfs_testout_v(data);
+
+        if (g->clk.gpc_pll.id == GM20B_GPC_PLL_C1) {
+                cfg = set_field(cfg, trim_sys_gpcpll_cfg_enable_m(),
+                                trim_sys_gpcpll_cfg_enable_no_f());
+                gk20a_writel(g, trim_sys_gpcpll_cfg_r(), cfg);
+                cfg = gk20a_readl(g, trim_sys_gpcpll_cfg_r());
+        }
+
         if (delay <= 0) {
                 nvgpu_err(g, "GPCPLL calibration timeout");
                 return -ETIMEDOUT;
         }
 
-        data = gk20a_readl(g, trim_sys_gpcpll_cfg3_r());
-        data = trim_sys_gpcpll_cfg3_dfs_testout_v(data);
         p->uvdet_offs = g->clk.pll_poweron_uv - data * ADC_SLOPE_UV;
         p->uvdet_slope = ADC_SLOPE_UV;
         return 0;