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Subject[PATCH 1/5] clk: qcom: Add support for SR2 PLLs
Date
Add support for SR2 type pll operations. SR2 is optimized for Time Interval
Error (TIE) or absolute jitter.

Signed-off-by: Georgi Djakov <georgi.djakov@linaro.org>
---
drivers/clk/qcom/clk-pll.c | 75 ++++++++++++++++++++++++++++++++++++++++++++
drivers/clk/qcom/clk-pll.h | 1 +
2 files changed, 76 insertions(+)

diff --git a/drivers/clk/qcom/clk-pll.c b/drivers/clk/qcom/clk-pll.c
index 245d5063a385..017eede87237 100644
--- a/drivers/clk/qcom/clk-pll.c
+++ b/drivers/clk/qcom/clk-pll.c
@@ -292,3 +292,78 @@ void clk_pll_configure_sr_hpm_lp(struct clk_pll *pll, struct regmap *regmap,
clk_pll_set_fsm_mode(pll, regmap, 0);
}
EXPORT_SYMBOL_GPL(clk_pll_configure_sr_hpm_lp);
+
+static int clk_pll_sr2_enable(struct clk_hw *hw)
+{
+ struct clk_pll *pll = to_clk_pll(hw);
+ int ret;
+ u32 mode;
+
+ ret = regmap_read(pll->clkr.regmap, pll->mode_reg, &mode);
+ if (ret)
+ return ret;
+
+ /* Disable PLL bypass mode. */
+ ret = regmap_update_bits(pll->clkr.regmap, pll->mode_reg, PLL_BYPASSNL,
+ PLL_BYPASSNL);
+ if (ret)
+ return ret;
+
+ /*
+ * H/W requires a 5us delay between disabling the bypass and
+ * de-asserting the reset. Delay 10us just to be safe.
+ */
+ udelay(10);
+
+ /* De-assert active-low PLL reset. */
+ ret = regmap_update_bits(pll->clkr.regmap, pll->mode_reg, PLL_RESET_N,
+ PLL_RESET_N);
+ if (ret)
+ return ret;
+
+ ret = wait_for_pll(pll);
+ if (ret)
+ return ret;
+
+ /* Enable PLL output. */
+ return regmap_update_bits(pll->clkr.regmap, pll->mode_reg, PLL_OUTCTRL,
+ PLL_OUTCTRL);
+}
+
+static int
+clk_pll_sr2_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long prate)
+{
+ struct clk_pll *pll = to_clk_pll(hw);
+ const struct pll_freq_tbl *f;
+ bool enabled;
+ u32 mode;
+ u32 enable_mask = PLL_OUTCTRL | PLL_BYPASSNL | PLL_RESET_N;
+
+ f = find_freq(pll->freq_tbl, rate);
+ if (!f)
+ return -EINVAL;
+
+ regmap_read(pll->clkr.regmap, pll->mode_reg, &mode);
+ enabled = (mode & enable_mask) == enable_mask;
+
+ if (enabled)
+ clk_pll_disable(hw);
+
+ regmap_update_bits(pll->clkr.regmap, pll->l_reg, 0x3ff, f->l);
+ regmap_update_bits(pll->clkr.regmap, pll->m_reg, 0x7ffff, f->m);
+ regmap_update_bits(pll->clkr.regmap, pll->n_reg, 0x7ffff, f->n);
+
+ if (enabled)
+ clk_pll_sr2_enable(hw);
+
+ return 0;
+}
+
+const struct clk_ops clk_pll_sr2_ops = {
+ .enable = clk_pll_sr2_enable,
+ .disable = clk_pll_disable,
+ .set_rate = clk_pll_sr2_set_rate,
+ .recalc_rate = clk_pll_recalc_rate,
+ .determine_rate = clk_pll_determine_rate,
+};
+EXPORT_SYMBOL_GPL(clk_pll_sr2_ops);
diff --git a/drivers/clk/qcom/clk-pll.h b/drivers/clk/qcom/clk-pll.h
index c9c0cda306d0..ffd0c63bddbc 100644
--- a/drivers/clk/qcom/clk-pll.h
+++ b/drivers/clk/qcom/clk-pll.h
@@ -62,6 +62,7 @@ struct clk_pll {

extern const struct clk_ops clk_pll_ops;
extern const struct clk_ops clk_pll_vote_ops;
+extern const struct clk_ops clk_pll_sr2_ops;

#define to_clk_pll(_hw) container_of(to_clk_regmap(_hw), struct clk_pll, clkr)


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