clk: qcom: clk-alpha-pll: Add support for Stromer PLLs

Commit Message

Kathiravan Thirumoorthy Dec. 27, 2022, 1:21 p.m. UTC

From: Varadarajan Narayanan <[e-mail]>

Add programming sequence support for managing the Stromer
PLLs.

Co-developed-by: Sricharan R <[e-mail]>
Signed-off-by: Sricharan R <[e-mail]>
Signed-off-by: Varadarajan Narayanan <[e-mail]>
Signed-off-by: Kathiravan T <[e-mail]>
---
Changes since V2:
	- splitted this patch from IPQ5018 series[1]
	- Rebased on linux-6.2-rc1
[1]
https://lore.kernel.org/linux-arm-msm/[e-mail]/

 drivers/clk/qcom/clk-alpha-pll.c | 100 ++++++++++++++++++++++++++++++-
 drivers/clk/qcom/clk-alpha-pll.h |   7 ++-
 2 files changed, 105 insertions(+), 2 deletions(-)

Patch

diff --git a/drivers/clk/qcom/clk-alpha-pll.c b/drivers/clk/qcom/clk-alpha-pll.c
index f9e4cfd7261c..29866100df08 100644
--- a/drivers/clk/qcom/clk-alpha-pll.c
+++ b/drivers/clk/qcom/clk-alpha-pll.c
@@ -204,9 +204,24 @@  const u8 clk_alpha_pll_regs[][PLL_OFF_MAX_REGS] = {
 		[PLL_OFF_CONFIG_CTL] = 0x1C,
 		[PLL_OFF_STATUS] = 0x20,
 	},
+	[CLK_ALPHA_PLL_TYPE_STROMER] = {
+		[PLL_OFF_L_VAL] = 0x08,
+		[PLL_OFF_ALPHA_VAL] = 0x10,
+		[PLL_OFF_ALPHA_VAL_U] = 0x14,
+		[PLL_OFF_USER_CTL] = 0x18,
+		[PLL_OFF_USER_CTL_U] = 0x1c,
+		[PLL_OFF_CONFIG_CTL] = 0x20,
+		[PLL_OFF_CONFIG_CTL_U] = 0xff,
+		[PLL_OFF_TEST_CTL] = 0x30,
+		[PLL_OFF_TEST_CTL_U] = 0x34,
+		[PLL_OFF_STATUS] = 0x28,
+	},
 };
 EXPORT_SYMBOL_GPL(clk_alpha_pll_regs);
 
+static unsigned long
+alpha_pll_round_rate(unsigned long rate, unsigned long prate, u32 *l, u64 *a,
+		     u32 alpha_width);
 /*
  * Even though 40 bits are present, use only 32 for ease of calculation.
  */
@@ -215,6 +230,8 @@  EXPORT_SYMBOL_GPL(clk_alpha_pll_regs);
 #define ALPHA_BITWIDTH		32U
 #define ALPHA_SHIFT(w)		min(w, ALPHA_BITWIDTH)
 
+#define	ALPHA_PLL_STATUS_REG_SHIFT	8
+
 #define PLL_HUAYRA_M_WIDTH		8
 #define PLL_HUAYRA_M_SHIFT		8
 #define PLL_HUAYRA_M_MASK		0xff
@@ -325,7 +342,7 @@  static void clk_alpha_pll_write_config(struct regmap *regmap, unsigned int reg,
 void clk_alpha_pll_configure(struct clk_alpha_pll *pll, struct regmap *regmap,
 			     const struct alpha_pll_config *config)
 {
-	u32 val, mask;
+	u32 val, val_u, mask, mask_u;
 
 	regmap_write(regmap, PLL_L_VAL(pll), config->l);
 	regmap_write(regmap, PLL_ALPHA_VAL(pll), config->alpha);
@@ -355,14 +372,85 @@  void clk_alpha_pll_configure(struct clk_alpha_pll *pll, struct regmap *regmap,
 	mask |= config->pre_div_mask;
 	mask |= config->post_div_mask;
 	mask |= config->vco_mask;
+	mask |= config->alpha_en_mask;
+	mask |= config->alpha_mode_mask;
 
 	regmap_update_bits(regmap, PLL_USER_CTL(pll), mask, val);
 
+	/* Stromer APSS PLL does not enable LOCK_DET by default, so enable it */
+	val_u = config->status_reg_val << ALPHA_PLL_STATUS_REG_SHIFT;
+	val_u |= config->lock_det;
+
+	mask_u = config->status_reg_mask;
+	mask_u |= config->lock_det;
+
+	if (val_u)
+		regmap_update_bits(regmap, PLL_USER_CTL_U(pll), mask_u, val_u);
+
+	if (config->test_ctl_val)
+		regmap_write(regmap, PLL_TEST_CTL(pll), config->test_ctl_val);
+
+	if (config->test_ctl_hi_val)
+		regmap_write(regmap, PLL_TEST_CTL_U(pll), config->test_ctl_hi_val);
+
 	if (pll->flags & SUPPORTS_FSM_MODE)
 		qcom_pll_set_fsm_mode(regmap, PLL_MODE(pll), 6, 0);
 }
 EXPORT_SYMBOL_GPL(clk_alpha_pll_configure);
 
+static int clk_alpha_pll_stromer_determine_rate(struct clk_hw *hw,
+						struct clk_rate_request *req)
+{
+	u32 l;
+	u64 a;
+
+	req->rate = alpha_pll_round_rate(req->rate, req->best_parent_rate,
+					 &l, &a, ALPHA_REG_BITWIDTH);
+
+	return 0;
+}
+
+static int clk_alpha_pll_stromer_set_rate(struct clk_hw *hw, unsigned long rate,
+					  unsigned long prate)
+{
+	struct clk_alpha_pll *pll = to_clk_alpha_pll(hw);
+	u32 l;
+	int ret;
+	u64 a;
+
+	rate = alpha_pll_round_rate(rate, prate, &l, &a, ALPHA_REG_BITWIDTH);
+
+	regmap_write(pll->clkr.regmap, PLL_L_VAL(pll), l);
+	regmap_write(pll->clkr.regmap, PLL_ALPHA_VAL(pll), a);
+	regmap_write(pll->clkr.regmap, PLL_ALPHA_VAL_U(pll),
+		     a >> ALPHA_BITWIDTH);
+
+	regmap_update_bits(pll->clkr.regmap, PLL_USER_CTL(pll),
+			   PLL_ALPHA_EN, PLL_ALPHA_EN);
+
+	if (!clk_hw_is_enabled(hw))
+		return 0;
+
+	/*
+	 * Stromer PLL supports Dynamic programming.
+	 * It allows the PLL frequency to be changed on-the-fly without first
+	 * execution of a shutdown procedure followed by a bring up procedure.
+	 */
+
+	regmap_update_bits(pll->clkr.regmap, PLL_MODE(pll), PLL_UPDATE,
+			   PLL_UPDATE);
+
+	ret = wait_for_pll_update(pll);
+	if (ret)
+		return ret;
+
+	ret = wait_for_pll_enable_lock(pll);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
 static int clk_alpha_pll_hwfsm_enable(struct clk_hw *hw)
 {
 	int ret;
@@ -1013,6 +1101,16 @@  const struct clk_ops clk_alpha_pll_hwfsm_ops = {
 };
 EXPORT_SYMBOL_GPL(clk_alpha_pll_hwfsm_ops);
 
+const struct clk_ops clk_alpha_pll_stromer_ops = {
+	.enable = clk_alpha_pll_enable,
+	.disable = clk_alpha_pll_disable,
+	.is_enabled = clk_alpha_pll_is_enabled,
+	.recalc_rate = clk_alpha_pll_recalc_rate,
+	.determine_rate = clk_alpha_pll_stromer_determine_rate,
+	.set_rate = clk_alpha_pll_stromer_set_rate,
+};
+EXPORT_SYMBOL_GPL(clk_alpha_pll_stromer_ops);
+
 const struct clk_ops clk_alpha_pll_fixed_trion_ops = {
 	.enable = clk_trion_pll_enable,
 	.disable = clk_trion_pll_disable,
diff --git a/drivers/clk/qcom/clk-alpha-pll.h b/drivers/clk/qcom/clk-alpha-pll.h
index 2bdae362c827..1d122919e275 100644
--- a/drivers/clk/qcom/clk-alpha-pll.h
+++ b/drivers/clk/qcom/clk-alpha-pll.h
@@ -1,5 +1,5 @@ 
 /* SPDX-License-Identifier: GPL-2.0 */
-/* Copyright (c) 2015, 2018, The Linux Foundation. All rights reserved. */
+/* Copyright (c) 2015, 2018, 2021 The Linux Foundation. All rights reserved. */
 
 #ifndef __QCOM_CLK_ALPHA_PLL_H__
 #define __QCOM_CLK_ALPHA_PLL_H__
@@ -22,6 +22,7 @@  enum {
 	CLK_ALPHA_PLL_TYPE_RIVIAN_EVO,
 	CLK_ALPHA_PLL_TYPE_DEFAULT_EVO,
 	CLK_ALPHA_PLL_TYPE_BRAMMO_EVO,
+	CLK_ALPHA_PLL_TYPE_STROMER,
 	CLK_ALPHA_PLL_TYPE_MAX,
 };
 
@@ -131,6 +132,9 @@  struct alpha_pll_config {
 	u32 post_div_mask;
 	u32 vco_val;
 	u32 vco_mask;
+	u32 status_reg_val;
+	u32 status_reg_mask;
+	u32 lock_det;
 };
 
 extern const struct clk_ops clk_alpha_pll_ops;
@@ -139,6 +143,7 @@  extern const struct clk_ops clk_alpha_pll_hwfsm_ops;
 extern const struct clk_ops clk_alpha_pll_postdiv_ops;
 extern const struct clk_ops clk_alpha_pll_huayra_ops;
 extern const struct clk_ops clk_alpha_pll_postdiv_ro_ops;
+extern const struct clk_ops clk_alpha_pll_stromer_ops;
 
 extern const struct clk_ops clk_alpha_pll_fabia_ops;
 extern const struct clk_ops clk_alpha_pll_fixed_fabia_ops;