clk: tegra: pll: Fix issues with rates for VCO PLLs
authorAndrew Bresticker <abrestic@chromium.org>
Thu, 18 Jun 2015 21:28:37 +0000 (17:28 -0400)
committerThierry Reding <treding@nvidia.com>
Thu, 17 Dec 2015 12:37:57 +0000 (13:37 +0100)
Without this change clk_get_rate would return the final output
rather than the VCO output as it would factor in the pdiv when
it shouldn't. This will cause problems for all dividers in the
subtree of the VCO PLL.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Reviewed-by: Benson Leung <bleung@chromium.org>
Signed-off-by: Rhyland Klein <rklein@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
drivers/clk/tegra/clk-pll.c

index d00e3289eb793cc1de7ab64edb95e434d91b5356..731c6857c895cd8739c98ef3d74af214f33fd345 100644 (file)
@@ -752,6 +752,8 @@ static int clk_pll_set_rate(struct clk_hw *hw, unsigned long rate,
                spin_lock_irqsave(pll->lock, flags);
 
        _get_pll_mnp(pll, &old_cfg);
+       if (pll->params->flags & TEGRA_PLL_VCO_OUT)
+               cfg.p = old_cfg.p;
 
        if (old_cfg.m != cfg.m || old_cfg.n != cfg.n || old_cfg.p != cfg.p ||
                old_cfg.sdm_data != cfg.sdm_data)
@@ -812,11 +814,15 @@ static unsigned long clk_pll_recalc_rate(struct clk_hw *hw,
 
        _get_pll_mnp(pll, &cfg);
 
-       pdiv = _hw_to_p_div(hw, cfg.p);
-       if (pdiv < 0) {
-               WARN(1, "Clock %s has invalid pdiv value : 0x%x\n",
-                       __clk_get_name(hw->clk), cfg.p);
+       if (pll->params->flags & TEGRA_PLL_VCO_OUT) {
                pdiv = 1;
+       } else {
+               pdiv = _hw_to_p_div(hw, cfg.p);
+               if (pdiv < 0) {
+                       WARN(1, "Clock %s has invalid pdiv value : 0x%x\n",
+                            clk_hw_get_name(hw), cfg.p);
+                       pdiv = 1;
+               }
        }
 
        if (pll->params->set_gain)
@@ -1103,6 +1109,8 @@ static int clk_pllxc_set_rate(struct clk_hw *hw, unsigned long rate,
                spin_lock_irqsave(pll->lock, flags);
 
        _get_pll_mnp(pll, &old_cfg);
+       if (pll->params->flags & TEGRA_PLL_VCO_OUT)
+               cfg.p = old_cfg.p;
 
        if (old_cfg.m != cfg.m || old_cfg.n != cfg.n || old_cfg.p != cfg.p)
                ret = _program_pll(hw, &cfg, rate);