gpu: nvgpu: fix gm20b round rate ops

Make the clk_round_rate ops consider the max rate supported by DVFS
while calculating the max frequency.

Bug 200233943

Change-Id: Ib36a40a29cb16231dd1442aa652a20819e0f4016
Signed-off-by: Srikar Srimath Tirumala <srikars@nvidia.com>
Reviewed-on: http://git-master/r/1281552
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

1 files changed, 6 insertions, 4 deletions

diff --git a/drivers/gpu/nvgpu/gm20b/clk_gm20b.c b/drivers/gpu/nvgpu/gm20b/clk_gm20b.c
index 7f0e3055..4f63f956 100644
--- a/drivers/gpu/nvgpu/gm20b/clk_gm20b.c
+++ b/drivers/gpu/nvgpu/gm20b/clk_gm20b.c
@@ -1266,13 +1266,16 @@ static long gm20b_round_rate(struct clk_hw *hw, unsigned long rate,
                              unsigned long *parent_rate)
 {
         struct clk_gk20a *clk = to_clk_gk20a(hw);
-        u32 freq, old_freq;
+        u32 freq;
         struct pll tmp_pll;
+        unsigned long maxrate;
+
+        maxrate = tegra_dvfs_get_maxrate(clk_get_parent(clk->tegra_clk));
+        if (rate > maxrate)
+                rate = maxrate;
 
         mutex_lock(&clk->clk_mutex);
-        old_freq = clk->gpc_pll.freq;
         freq = rate_gpu_to_gpc2clk(rate);
-
         if (freq > gpc_pll_params.max_freq)
                 freq = gpc_pll_params.max_freq;
         else if (freq < gpc_pll_params.min_freq)
@@ -1280,7 +1283,6 @@ static long gm20b_round_rate(struct clk_hw *hw, unsigned long rate,
 
         tmp_pll = clk->gpc_pll;
         clk_config_pll(clk, &tmp_pll, &gpc_pll_params, &freq, true);
-
         mutex_unlock(&clk->clk_mutex);
 
         return rate_gpc2clk_to_gpu(tmp_pll.freq);