clk: tegra: pll: Add logic for SS
Add some logic for Spread Spectrum control. It is used in conjuncture
with SDM fractional dividers. SSC has to be disabled when we configure
the divider settings.
Signed-off-by: Bill Huang <bilhuang@nvidia.com>
Signed-off-by: Rhyland Klein <rklein@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
diff --git a/drivers/clk/tegra/clk-pll.c b/drivers/clk/tegra/clk-pll.c
index 8901004..7ef0886 100644
--- a/drivers/clk/tegra/clk-pll.c
+++ b/drivers/clk/tegra/clk-pll.c
@@ -658,6 +658,26 @@
pll_writel_misc(val, pll);
}
+static void pll_clk_start_ss(struct tegra_clk_pll *pll)
+{
+ if (pll->params->defaults_set && pll->params->ssc_ctrl_reg) {
+ u32 val = pll_readl(pll->params->ssc_ctrl_reg, pll);
+
+ val |= pll->params->ssc_ctrl_en_mask;
+ pll_writel(val, pll->params->ssc_ctrl_reg, pll);
+ }
+}
+
+static void pll_clk_stop_ss(struct tegra_clk_pll *pll)
+{
+ if (pll->params->defaults_set && pll->params->ssc_ctrl_reg) {
+ u32 val = pll_readl(pll->params->ssc_ctrl_reg, pll);
+
+ val &= ~pll->params->ssc_ctrl_en_mask;
+ pll_writel(val, pll->params->ssc_ctrl_reg, pll);
+ }
+}
+
static int _program_pll(struct clk_hw *hw, struct tegra_clk_pll_freq_table *cfg,
unsigned long rate)
{
@@ -676,8 +696,10 @@
return 0;
}
- if (state)
+ if (state) {
+ pll_clk_stop_ss(pll);
_clk_pll_disable(hw);
+ }
if (!pll->params->defaults_set && pll->params->set_defaults)
pll->params->set_defaults(pll);
@@ -690,6 +712,7 @@
if (state) {
_clk_pll_enable(hw);
ret = clk_pll_wait_for_lock(pll);
+ pll_clk_start_ss(pll);
}
return ret;
diff --git a/drivers/clk/tegra/clk.h b/drivers/clk/tegra/clk.h
index 8dac213..4883507 100644
--- a/drivers/clk/tegra/clk.h
+++ b/drivers/clk/tegra/clk.h
@@ -184,6 +184,8 @@
* @sdm_din_mask: Mask of SDM divider bits
* @sdm_ctrl_reg: Register offset where SDM enable is
* @sdm_ctrl_en_mask: Mask of SDM enable bit
+ * @ssc_ctrl_reg: Register offset where SSC settings are
+ * @ssc_ctrl_en_mask: Mask of SSC enable bit
* @aux_reg: AUX register offset
* @dyn_ramp_reg: Dynamic ramp control register offset
* @ext_misc_reg: Miscellaneous control register offsets
@@ -262,6 +264,8 @@
u32 sdm_din_mask;
u32 sdm_ctrl_reg;
u32 sdm_ctrl_en_mask;
+ u32 ssc_ctrl_reg;
+ u32 ssc_ctrl_en_mask;
u32 aux_reg;
u32 dyn_ramp_reg;
u32 ext_misc_reg[MAX_PLL_MISC_REG_COUNT];