Message-ID: <20250728201435.3505594-3-prabhakar.mahadev-lad.rj@bp.renesas.com>
Date: Mon, 28 Jul 2025 21:14:31 +0100
From: Prabhakar <prabhakar.csengg@...il.com>
To: Geert Uytterhoeven <geert+renesas@...der.be>,
	Andrzej Hajda <andrzej.hajda@...el.com>,
	Neil Armstrong <neil.armstrong@...aro.org>,
	Robert Foss <rfoss@...nel.org>,
	Laurent Pinchart <Laurent.pinchart@...asonboard.com>,
	Jonas Karlman <jonas@...boo.se>,
	Jernej Skrabec <jernej.skrabec@...il.com>,
	David Airlie <airlied@...il.com>,
	Simona Vetter <simona@...ll.ch>,
	Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>,
	Maxime Ripard <mripard@...nel.org>,
	Thomas Zimmermann <tzimmermann@...e.de>,
	Rob Herring <robh@...nel.org>,
	Krzysztof Kozlowski <krzk+dt@...nel.org>,
	Conor Dooley <conor+dt@...nel.org>,
	Michael Turquette <mturquette@...libre.com>,
	Stephen Boyd <sboyd@...nel.org>,
	Biju Das <biju.das.jz@...renesas.com>,
	Magnus Damm <magnus.damm@...il.com>
Cc: dri-devel@...ts.freedesktop.org,
	devicetree@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	linux-renesas-soc@...r.kernel.org,
	linux-clk@...r.kernel.org,
	Prabhakar <prabhakar.csengg@...il.com>,
	Fabrizio Castro <fabrizio.castro.jz@...esas.com>,
	Tommaso Merciai <tommaso.merciai.xr@...renesas.com>,
	Lad Prabhakar <prabhakar.mahadev-lad.rj@...renesas.com>
Subject: [PATCH v7 2/6] clk: renesas: rzv2h-cpg: Add support for DSI clocks

From: Lad Prabhakar <prabhakar.mahadev-lad.rj@...renesas.com>

Add support for PLLDSI and PLLDSI divider clocks.

Introduce the `renesas-rzv2h-cpg-pll.h` header to centralize and share
PLLDSI related data structures, limits, and algorithms between the
RZ/V2H(P) CPG and DSI drivers.

The DSI PLL is functionally similar to the CPG's PLLDSI, but has slightly
different parameter limits and omits the programmable divider present in
CPG. To ensure precise frequency calculations, especially for milliHz-level
accuracy needed by the DSI driver, the shared algorithm allows both drivers
to compute PLL parameters consistently using the same logic and input
clock.

Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@...esas.com>
Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@...esas.com>
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@...renesas.com>
---
v6->v7:
- Made struct rzv2h_pll_limits more modular also added Ffout limits
- Made the alogirithm modular and also added apis based on the
  needs for lvds and dpi

v5->v6:
- Renamed CPG_PLL_STBY_SSCGEN_WEN to CPG_PLL_STBY_SSC_EN_WEN
- Updated CPG_PLL_CLK1_DIV_K, CPG_PLL_CLK1_DIV_M, and
  CPG_PLL_CLK1_DIV_P macros to use GENMASK
- Updated req->rate in rzv2h_cpg_plldsi_div_determine_rate()
- Dropped the cast in rzv2h_cpg_plldsi_div_set_rate()
- Dropped rzv2h_cpg_plldsi_round_rate() and implemented
  rzv2h_cpg_plldsi_determine_rate() instead
- Made use of FIELD_PREP()
- Moved CPG_CSDIV1 macro in patch 2/4
- Dropped two_pow_s in rzv2h_dsi_get_pll_parameters_values()
- Used mul_u32_u32() while calculating output_m and output_k_range
- Used div_s64() instead of div64_s64() while calculating
  pll_k
- Used mul_u32_u32() while calculating fvco and fvco checks
- Rounded the final output using DIV_U64_ROUND_CLOSEST()

v4->v5:
- No changes

v3->v4:
- Corrected parameter name in rzv2h_dsi_get_pll_parameters_values()
  description freq_millihz

v2->v3:
- Update the commit message to clarify the purpose of `renesas-rzv2h-dsi.h`
  header
- Used mul_u32_u32() in rzv2h_cpg_plldsi_div_determine_rate()
- Replaced *_mhz to *_millihz for clarity
- Updated u64->u32 for fvco limits
- Initialized the members in declaration order for
  RZV2H_CPG_PLL_DSI_LIMITS() macro
- Used clk_div_mask() in rzv2h_cpg_plldsi_div_recalc_rate()
- Replaced `unsigned long long` with u64
- Dropped rzv2h_cpg_plldsi_clk_recalc_rate() and reused
  rzv2h_cpg_pll_clk_recalc_rate() instead
- In rzv2h_cpg_plldsi_div_set_rate() followed the same style
  of RMW-operation as done in the other functions
- Renamed rzv2h_cpg_plldsi_set_rate() to rzv2h_cpg_pll_set_rate()
- Dropped rzv2h_cpg_plldsi_clk_register() and reused
  rzv2h_cpg_pll_clk_register() instead
- Added a gaurd in renesas-rzv2h-dsi.h header

v1->v2:
- No changes
---
 drivers/clk/renesas/rzv2h-cpg.c           | 309 ++++++++++++++++-
 drivers/clk/renesas/rzv2h-cpg.h           |  19 +-
 include/linux/clk/renesas-rzv2h-cpg-pll.h | 395 ++++++++++++++++++++++
 3 files changed, 712 insertions(+), 11 deletions(-)
 create mode 100644 include/linux/clk/renesas-rzv2h-cpg-pll.h

diff --git a/drivers/clk/renesas/rzv2h-cpg.c b/drivers/clk/renesas/rzv2h-cpg.c
index f468afbb54e2..2378cf92da5e 100644
--- a/drivers/clk/renesas/rzv2h-cpg.c
+++ b/drivers/clk/renesas/rzv2h-cpg.c
@@ -14,9 +14,13 @@
 #include <linux/bitfield.h>
 #include <linux/clk.h>
 #include <linux/clk-provider.h>
+#include <linux/clk/renesas-rzv2h-cpg-pll.h>
 #include <linux/delay.h>
 #include <linux/init.h>
 #include <linux/iopoll.h>
+#include <linux/math.h>
+#include <linux/math64.h>
+#include <linux/minmax.h>
 #include <linux/mod_devicetable.h>
 #include <linux/module.h>
 #include <linux/of.h>
@@ -26,6 +30,7 @@
 #include <linux/refcount.h>
 #include <linux/reset-controller.h>
 #include <linux/string_choices.h>
+#include <linux/units.h>
 
 #include <dt-bindings/clock/renesas-cpg-mssr.h>
 
@@ -47,13 +52,15 @@
 
 #define CPG_PLL_STBY(x)		((x))
 #define CPG_PLL_STBY_RESETB	BIT(0)
+#define CPG_PLL_STBY_SSC_EN	BIT(2)
 #define CPG_PLL_STBY_RESETB_WEN	BIT(16)
+#define CPG_PLL_STBY_SSC_EN_WEN BIT(18)
 #define CPG_PLL_CLK1(x)		((x) + 0x004)
-#define CPG_PLL_CLK1_KDIV(x)	((s16)FIELD_GET(GENMASK(31, 16), (x)))
-#define CPG_PLL_CLK1_MDIV(x)	FIELD_GET(GENMASK(15, 6), (x))
-#define CPG_PLL_CLK1_PDIV(x)	FIELD_GET(GENMASK(5, 0), (x))
+#define CPG_PLL_CLK1_KDIV	GENMASK(31, 16)
+#define CPG_PLL_CLK1_MDIV	GENMASK(15, 6)
+#define CPG_PLL_CLK1_PDIV	GENMASK(5, 0)
 #define CPG_PLL_CLK2(x)		((x) + 0x008)
-#define CPG_PLL_CLK2_SDIV(x)	FIELD_GET(GENMASK(2, 0), (x))
+#define CPG_PLL_CLK2_SDIV	GENMASK(2, 0)
 #define CPG_PLL_MON(x)		((x) + 0x010)
 #define CPG_PLL_MON_RESETB	BIT(0)
 #define CPG_PLL_MON_LOCK	BIT(4)
@@ -65,6 +72,22 @@
 
 #define CPG_CLKSTATUS0		(0x700)
 
+/* On RZ/G3E SoC we have two DSI PLLs */
+#define MAX_CPG_DSI_PLL		2
+
+/**
+ * struct rzv2h_pll_dsi_info - PLL DSI information, holds the limits and parameters
+ *
+ * @pll_dsi_limits: PLL DSI parameters limits
+ * @pll_dsi_parameters: Calculated PLL DSI parameters
+ * @req_pll_dsi_rate: Requested PLL DSI rate
+ */
+struct rzv2h_pll_dsi_info {
+	const struct rzv2h_pll_limits *pll_dsi_limits;
+	struct rzv2h_pll_div_pars pll_dsi_parameters;
+	unsigned long req_pll_dsi_rate;
+};
+
 /**
  * struct rzv2h_cpg_priv - Clock Pulse Generator Private Data
  *
@@ -80,6 +103,7 @@
  * @ff_mod_status_ops: Fixed Factor Module Status Clock operations
  * @mstop_count: Array of mstop values
  * @rcdev: Reset controller entity
+ * @pll_dsi_info: Array of PLL DSI information, holds the limits and parameters
  */
 struct rzv2h_cpg_priv {
 	struct device *dev;
@@ -98,6 +122,8 @@ struct rzv2h_cpg_priv {
 	atomic_t *mstop_count;
 
 	struct reset_controller_dev rcdev;
+
+	struct rzv2h_pll_dsi_info pll_dsi_info[MAX_CPG_DSI_PLL];
 };
 
 #define rcdev_to_priv(x)	container_of(x, struct rzv2h_cpg_priv, rcdev)
@@ -168,6 +194,253 @@ struct rzv2h_ff_mod_status_clk {
 #define to_rzv2h_ff_mod_status_clk(_hw) \
 	container_of(_hw, struct rzv2h_ff_mod_status_clk, fix.hw)
 
+/**
+ * struct rzv2h_plldsi_div_clk - PLL DSI DDIV clock
+ *
+ * @dtable: divider table
+ * @priv: CPG private data
+ * @hw: divider clk
+ * @ddiv: divider configuration
+ */
+struct rzv2h_plldsi_div_clk {
+	const struct clk_div_table *dtable;
+	struct rzv2h_cpg_priv *priv;
+	struct clk_hw hw;
+	struct ddiv ddiv;
+};
+
+#define to_plldsi_div_clk(_hw) \
+	container_of(_hw, struct rzv2h_plldsi_div_clk, hw)
+
+static unsigned long rzv2h_cpg_plldsi_div_recalc_rate(struct clk_hw *hw,
+						      unsigned long parent_rate)
+{
+	struct rzv2h_plldsi_div_clk *dsi_div = to_plldsi_div_clk(hw);
+	struct rzv2h_cpg_priv *priv = dsi_div->priv;
+	struct ddiv ddiv = dsi_div->ddiv;
+	u32 div;
+
+	div = readl(priv->base + ddiv.offset);
+	div >>= ddiv.shift;
+	div &= clk_div_mask(ddiv.width);
+	div = dsi_div->dtable[div].div;
+
+	return DIV_ROUND_CLOSEST_ULL(parent_rate, div);
+}
+
+static struct rzv2h_pll_dsi_info *rzv2h_get_pll_dsi_info(struct clk_hw *pll_dsi,
+							 struct rzv2h_cpg_priv *priv)
+{
+	struct pll_clk *pll_clk = to_pll(pll_dsi);
+
+	return &priv->pll_dsi_info[pll_clk->pll.instance];
+}
+
+static int rzv2h_cpg_plldsi_div_determine_rate(struct clk_hw *hw,
+					       struct clk_rate_request *req)
+{
+	struct rzv2h_plldsi_div_clk *dsi_div = to_plldsi_div_clk(hw);
+	struct rzv2h_cpg_priv *priv = dsi_div->priv;
+	struct rzv2h_pll_div_pars *dsi_params;
+	struct rzv2h_pll_dsi_info *dsi_info;
+	u64 rate_millihz;
+
+	dsi_info = rzv2h_get_pll_dsi_info(clk_hw_get_parent(hw), priv);
+	dsi_params = &dsi_info->pll_dsi_parameters;
+
+	rate_millihz = mul_u32_u32(req->rate, MILLI);
+	if (rate_millihz == dsi_params->div.error_millihz + dsi_params->div.freq_millihz)
+		goto exit_determine_rate;
+
+	if (!rzv2h_get_pll_dtable_pars(dsi_info->pll_dsi_limits, dsi_params, dsi_div->dtable,
+				       rate_millihz)) {
+		dev_err(priv->dev,
+			"failed to determine rate for req->rate: %lu\n",
+			req->rate);
+		return -EINVAL;
+	}
+
+exit_determine_rate:
+	req->rate = DIV_ROUND_CLOSEST_ULL(dsi_params->div.freq_millihz, MILLI);
+	req->best_parent_rate = req->rate * dsi_params->div.divider_value;
+	dsi_info->req_pll_dsi_rate = req->best_parent_rate;
+
+	return 0;
+};
+
+static int rzv2h_cpg_plldsi_div_set_rate(struct clk_hw *hw,
+					 unsigned long rate,
+					 unsigned long parent_rate)
+{
+	struct rzv2h_plldsi_div_clk *dsi_div = to_plldsi_div_clk(hw);
+	struct rzv2h_cpg_priv *priv = dsi_div->priv;
+	struct rzv2h_pll_div_pars *dsi_params;
+	struct rzv2h_pll_dsi_info *dsi_info;
+	struct ddiv ddiv = dsi_div->ddiv;
+	const struct clk_div_table *clkt;
+	bool divider_found = false;
+	u32 val, shift;
+
+	dsi_info = rzv2h_get_pll_dsi_info(clk_hw_get_parent(hw), priv);
+	dsi_params = &dsi_info->pll_dsi_parameters;
+
+	for (clkt = dsi_div->dtable; clkt->div; clkt++) {
+		if (clkt->div == dsi_params->div.divider_value) {
+			divider_found = true;
+			break;
+		}
+	}
+
+	if (!divider_found)
+		return -EINVAL;
+
+	shift = ddiv.shift;
+	val = readl(priv->base + ddiv.offset) | DDIV_DIVCTL_WEN(shift);
+	val &= ~(clk_div_mask(ddiv.width) << shift);
+	val |= clkt->val << shift;
+	writel(val, priv->base + ddiv.offset);
+
+	return 0;
+};
+
+static const struct clk_ops rzv2h_cpg_plldsi_div_ops = {
+	.recalc_rate = rzv2h_cpg_plldsi_div_recalc_rate,
+	.determine_rate = rzv2h_cpg_plldsi_div_determine_rate,
+	.set_rate = rzv2h_cpg_plldsi_div_set_rate,
+};
+
+static struct clk * __init
+rzv2h_cpg_plldsi_div_clk_register(const struct cpg_core_clk *core,
+				  struct rzv2h_cpg_priv *priv)
+{
+	struct rzv2h_plldsi_div_clk *clk_hw_data;
+	struct clk **clks = priv->clks;
+	struct clk_init_data init;
+	const struct clk *parent;
+	const char *parent_name;
+	struct clk_hw *clk_hw;
+	int ret;
+
+	parent = clks[core->parent];
+	if (IS_ERR(parent))
+		return ERR_CAST(parent);
+
+	clk_hw_data = devm_kzalloc(priv->dev, sizeof(*clk_hw_data), GFP_KERNEL);
+	if (!clk_hw_data)
+		return ERR_PTR(-ENOMEM);
+
+	clk_hw_data->priv = priv;
+	clk_hw_data->ddiv = core->cfg.ddiv;
+	clk_hw_data->dtable = core->dtable;
+
+	parent_name = __clk_get_name(parent);
+	init.name = core->name;
+	init.ops = &rzv2h_cpg_plldsi_div_ops;
+	init.flags = core->flag;
+	init.parent_names = &parent_name;
+	init.num_parents = 1;
+
+	clk_hw = &clk_hw_data->hw;
+	clk_hw->init = &init;
+
+	ret = devm_clk_hw_register(priv->dev, clk_hw);
+	if (ret)
+		return ERR_PTR(ret);
+
+	return clk_hw->clk;
+}
+
+static int rzv2h_cpg_plldsi_determine_rate(struct clk_hw *hw,
+					   struct clk_rate_request *req)
+{
+	struct pll_clk *pll_clk = to_pll(hw);
+	struct rzv2h_cpg_priv *priv = pll_clk->priv;
+	struct rzv2h_pll_dsi_info *dsi_info;
+	u64 rate_millihz;
+
+	dsi_info = &priv->pll_dsi_info[pll_clk->pll.instance];
+	/* check if the divider has already invoked the algorithm */
+	if (req->rate == dsi_info->req_pll_dsi_rate)
+		return 0;
+
+	/* If the req->rate doesn't match we do the calculation assuming there is no divider */
+	rate_millihz = mul_u32_u32(req->rate, MILLI);
+	if (!rzv2h_get_pll_pars(dsi_info->pll_dsi_limits,
+				&dsi_info->pll_dsi_parameters.pll, rate_millihz)) {
+		dev_err(priv->dev,
+			"failed to determine rate for req->rate: %lu\n",
+			req->rate);
+		return -EINVAL;
+	}
+
+	req->rate = DIV_ROUND_CLOSEST_ULL(dsi_info->pll_dsi_parameters.pll.freq_millihz, MILLI);
+	dsi_info->req_pll_dsi_rate = req->rate;
+
+	return 0;
+}
+
+static int rzv2h_cpg_pll_set_rate(struct pll_clk *pll_clk,
+				  struct rzv2h_pll_pars *params,
+				  bool ssc_disable)
+{
+	struct rzv2h_cpg_priv *priv = pll_clk->priv;
+	u16 offset = pll_clk->pll.offset;
+	u32 val;
+	int ret;
+
+	/* Put PLL into standby mode */
+	writel(CPG_PLL_STBY_RESETB_WEN, priv->base + CPG_PLL_STBY(offset));
+	ret = readl_poll_timeout_atomic(priv->base + CPG_PLL_MON(offset),
+					val, !(val & CPG_PLL_MON_LOCK),
+					100, 2000);
+	if (ret) {
+		dev_err(priv->dev, "Failed to put PLLDSI into standby mode");
+		return ret;
+	}
+
+	/* Output clock setting 1 */
+	writel(FIELD_PREP(CPG_PLL_CLK1_KDIV, (u16)params->k) |
+	       FIELD_PREP(CPG_PLL_CLK1_MDIV, params->m) |
+	       FIELD_PREP(CPG_PLL_CLK1_PDIV, params->p),
+	       priv->base + CPG_PLL_CLK1(offset));
+
+	/* Output clock setting 2 */
+	val = readl(priv->base + CPG_PLL_CLK2(offset));
+	writel((val & ~CPG_PLL_CLK2_SDIV) | FIELD_PREP(CPG_PLL_CLK2_SDIV, params->s),
+	       priv->base + CPG_PLL_CLK2(offset));
+
+	/* Put PLL to normal mode */
+	if (ssc_disable)
+		val = CPG_PLL_STBY_SSC_EN_WEN;
+	else
+		val = CPG_PLL_STBY_SSC_EN_WEN | CPG_PLL_STBY_SSC_EN;
+	writel(val | CPG_PLL_STBY_RESETB_WEN | CPG_PLL_STBY_RESETB,
+	       priv->base + CPG_PLL_STBY(offset));
+
+	/* PLL normal mode transition, output clock stability check */
+	ret = readl_poll_timeout_atomic(priv->base + CPG_PLL_MON(offset),
+					val, (val & CPG_PLL_MON_LOCK),
+					100, 2000);
+	if (ret) {
+		dev_err(priv->dev, "Failed to put PLLDSI into normal mode");
+		return ret;
+	}
+
+	return 0;
+};
+
+static int rzv2h_cpg_plldsi_set_rate(struct clk_hw *hw, unsigned long rate,
+				     unsigned long parent_rate)
+{
+	struct pll_clk *pll_clk = to_pll(hw);
+	struct rzv2h_pll_dsi_info *dsi_info;
+	struct rzv2h_cpg_priv *priv = pll_clk->priv;
+
+	dsi_info = &priv->pll_dsi_info[pll_clk->pll.instance];
+
+	return rzv2h_cpg_pll_set_rate(pll_clk, &dsi_info->pll_dsi_parameters.pll, true);
+};
+
 static int rzv2h_cpg_pll_clk_is_enabled(struct clk_hw *hw)
 {
 	struct pll_clk *pll_clk = to_pll(hw);
@@ -231,12 +504,19 @@ static unsigned long rzv2h_cpg_pll_clk_recalc_rate(struct clk_hw *hw,
 	clk1 = readl(priv->base + CPG_PLL_CLK1(pll.offset));
 	clk2 = readl(priv->base + CPG_PLL_CLK2(pll.offset));
 
-	rate = mul_u64_u32_shr(parent_rate, (CPG_PLL_CLK1_MDIV(clk1) << 16) +
-			       CPG_PLL_CLK1_KDIV(clk1), 16 + CPG_PLL_CLK2_SDIV(clk2));
+	rate = mul_u64_u32_shr(parent_rate, (FIELD_GET(CPG_PLL_CLK1_MDIV, clk1) << 16) +
+			       (s16)FIELD_GET(CPG_PLL_CLK1_KDIV, clk1),
+			       16 + FIELD_GET(CPG_PLL_CLK2_SDIV, clk2));
 
-	return DIV_ROUND_CLOSEST_ULL(rate, CPG_PLL_CLK1_PDIV(clk1));
+	return DIV_ROUND_CLOSEST_ULL(rate, FIELD_GET(CPG_PLL_CLK1_PDIV, clk1));
 }
 
+static const struct clk_ops rzv2h_cpg_plldsi_ops = {
+	.recalc_rate = rzv2h_cpg_pll_clk_recalc_rate,
+	.determine_rate = rzv2h_cpg_plldsi_determine_rate,
+	.set_rate = rzv2h_cpg_plldsi_set_rate,
+};
+
 static const struct clk_ops rzv2h_cpg_pll_ops = {
 	.is_enabled = rzv2h_cpg_pll_clk_is_enabled,
 	.enable = rzv2h_cpg_pll_clk_enable,
@@ -246,7 +526,8 @@ static const struct clk_ops rzv2h_cpg_pll_ops = {
 static struct clk * __init
 rzv2h_cpg_pll_clk_register(const struct cpg_core_clk *core,
 			   struct rzv2h_cpg_priv *priv,
-			   const struct clk_ops *ops)
+			   const struct clk_ops *ops,
+			   bool is_plldsi)
 {
 	struct device *dev = priv->dev;
 	struct clk_init_data init;
@@ -263,6 +544,10 @@ rzv2h_cpg_pll_clk_register(const struct cpg_core_clk *core,
 	if (!pll_clk)
 		return ERR_PTR(-ENOMEM);
 
+	if (is_plldsi)
+		priv->pll_dsi_info[core->cfg.pll.instance].pll_dsi_limits =
+			core->cfg.pll.limits;
+
 	parent_name = __clk_get_name(parent);
 	init.name = core->name;
 	init.ops = ops;
@@ -589,7 +874,7 @@ rzv2h_cpg_register_core_clk(const struct cpg_core_clk *core,
 		clk = rzv2h_cpg_fixed_mod_status_clk_register(core, priv);
 		break;
 	case CLK_TYPE_PLL:
-		clk = rzv2h_cpg_pll_clk_register(core, priv, &rzv2h_cpg_pll_ops);
+		clk = rzv2h_cpg_pll_clk_register(core, priv, &rzv2h_cpg_pll_ops, false);
 		break;
 	case CLK_TYPE_DDIV:
 		clk = rzv2h_cpg_ddiv_clk_register(core, priv);
@@ -597,6 +882,12 @@ rzv2h_cpg_register_core_clk(const struct cpg_core_clk *core,
 	case CLK_TYPE_SMUX:
 		clk = rzv2h_cpg_mux_clk_register(core, priv);
 		break;
+	case CLK_TYPE_PLLDSI:
+		clk = rzv2h_cpg_pll_clk_register(core, priv, &rzv2h_cpg_plldsi_ops, true);
+		break;
+	case CLK_TYPE_PLLDSI_DIV:
+		clk = rzv2h_cpg_plldsi_div_clk_register(core, priv);
+		break;
 	default:
 		goto fail;
 	}
diff --git a/drivers/clk/renesas/rzv2h-cpg.h b/drivers/clk/renesas/rzv2h-cpg.h
index e2053049c299..637803bc1e89 100644
--- a/drivers/clk/renesas/rzv2h-cpg.h
+++ b/drivers/clk/renesas/rzv2h-cpg.h
@@ -22,15 +22,20 @@ struct pll {
 	unsigned int offset:9;
 	unsigned int has_clkn:1;
 	unsigned int instance:2;
+	const struct rzv2h_pll_limits *limits;
 };
 
-#define PLL_PACK(_offset, _has_clkn, _instance) \
+#define PLL_PACK_LIMITS(_offset, _has_clkn, _instance, _limits) \
 	((struct pll){ \
 		.offset = _offset, \
 		.has_clkn = _has_clkn, \
-		.instance = _instance \
+		.instance = _instance, \
+		.limits = _limits \
 	})
 
+#define PLL_PACK(_offset, _has_clkn, _instance) \
+	PLL_PACK_LIMITS(_offset, _has_clkn, _instance, NULL)
+
 #define PLLCA55		PLL_PACK(0x60, 1, 0)
 #define PLLGPU		PLL_PACK(0x120, 1, 0)
 
@@ -191,6 +196,8 @@ enum clk_types {
 	CLK_TYPE_PLL,
 	CLK_TYPE_DDIV,		/* Dynamic Switching Divider */
 	CLK_TYPE_SMUX,		/* Static Mux */
+	CLK_TYPE_PLLDSI,	/* PLLDSI */
+	CLK_TYPE_PLLDSI_DIV,	/* PLLDSI divider */
 };
 
 #define DEF_TYPE(_name, _id, _type...) \
@@ -221,6 +228,14 @@ enum clk_types {
 		 .num_parents = ARRAY_SIZE(_parent_names), \
 		 .flag = CLK_SET_RATE_PARENT, \
 		 .mux_flags = CLK_MUX_HIWORD_MASK)
+#define DEF_PLLDSI(_name, _id, _parent, _pll_packed) \
+	DEF_TYPE(_name, _id, CLK_TYPE_PLLDSI, .parent = _parent, .cfg.pll = _pll_packed)
+#define DEF_PLLDSI_DIV(_name, _id, _parent, _ddiv_packed, _dtable) \
+	DEF_TYPE(_name, _id, CLK_TYPE_PLLDSI_DIV, \
+		 .cfg.ddiv = _ddiv_packed, \
+		 .dtable = _dtable, \
+		 .parent = _parent, \
+		 .flag = CLK_SET_RATE_PARENT)
 
 /**
  * struct rzv2h_mod_clk - Module Clocks definitions
diff --git a/include/linux/clk/renesas-rzv2h-cpg-pll.h b/include/linux/clk/renesas-rzv2h-cpg-pll.h
new file mode 100644
index 000000000000..f34904cba8de
--- /dev/null
+++ b/include/linux/clk/renesas-rzv2h-cpg-pll.h
@@ -0,0 +1,395 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Renesas RZ/V2H(P) CPG PLL helper
+ *
+ * Copyright (C) 2025 Renesas Electronics Corp.
+ */
+#ifndef __RENESAS_RZV2H_CPG_PLL_H__
+#define __RENESAS_RZV2H_CPG_PLL_H__
+
+#include <linux/clk-provider.h>
+#include <linux/limits.h>
+#include <linux/math.h>
+#include <linux/math64.h>
+#include <linux/units.h>
+
+#define RZ_V2H_OSC_CLK_IN_MEGA		(24 * MEGA)
+#define RZV2H_MAX_DIV_TABLES		(16)
+
+/**
+ * struct rzv2h_pll_limits - PLL parameter constraints
+ *
+ * This structure defines the minimum and maximum allowed values for
+ * various parameters used to configure a PLL. These limits ensure
+ * the PLL operates within valid and stable ranges.
+ *
+ * @fout: Output frequency range (in MHz)
+ * @fout.min: Minimum allowed output frequency
+ * @fout.max: Maximum allowed output frequency
+ *
+ * @fvco: PLL oscillation frequency range (in MHz)
+ * @fvco.min: Minimum allowed VCO frequency
+ * @fvco.max: Maximum allowed VCO frequency
+ *
+ * @m: Main-divider range
+ * @m.min: Minimum main-divider value
+ * @m.max: Maximum main-divider value
+ *
+ * @p: Pre-divider range
+ * @p.min: Minimum pre-divider value
+ * @p.max: Maximum pre-divider value
+ *
+ * @s: Divider range
+ * @s.min: Minimum divider value
+ * @s.max: Maximum divider value
+ *
+ * @k: Delta-sigma modulator range (signed)
+ * @k.min: Minimum delta-sigma value
+ * @k.max: Maximum delta-sigma value
+ */
+struct rzv2h_pll_limits {
+	struct {
+		u32 min;
+		u32 max;
+	} fout;
+
+	struct {
+		u32 min;
+		u32 max;
+	} fvco;
+
+	struct {
+		u16 min;
+		u16 max;
+	} m;
+
+	struct {
+		u8 min;
+		u8 max;
+	} p;
+
+	struct {
+		u8 min;
+		u8 max;
+	} s;
+
+	struct {
+		s16 min;
+		s16 max;
+	} k;
+};
+
+/**
+ * struct rzv2h_pll_pars - PLL configuration parameters
+ *
+ * This structure contains the configuration parameters for the
+ * Phase-Locked Loop (PLL), used to achieve a specific output frequency.
+ *
+ * @m: Main divider value
+ * @p: Pre-divider value
+ * @s: Output divider value
+ * @k: Delta-sigma modulation value
+ * @freq_millihz: Calculated PLL output frequency in millihertz
+ * @error_millihz: Frequency error from target in millihertz (signed)
+ */
+struct rzv2h_pll_pars {
+	u16 m;
+	u8 p;
+	u8 s;
+	s16 k;
+	u64 freq_millihz;
+	s64 error_millihz;
+};
+
+/**
+ * struct rzv2h_pll_div_pars - PLL parameters with post-divider
+ *
+ * This structure is used for PLLs that include an additional post-divider
+ * stage after the main PLL block. It contains both the PLL configuration
+ * parameters and the resulting frequency/error values after the divider.
+ *
+ * @pll: Main PLL configuration parameters (see struct rzv2h_pll_pars)
+ *
+ * @div: Post-divider configuration and result
+ * @div.divider_value: Divider applied to the PLL output
+ * @div.freq_millihz: Output frequency after divider in millihertz
+ * @div.error_millihz: Frequency error from target in millihertz (signed)
+ */
+struct rzv2h_pll_div_pars {
+	struct rzv2h_pll_pars pll;
+	struct {
+		u8 divider_value;
+		u64 freq_millihz;
+		s64 error_millihz;
+	} div;
+};
+
+#define RZV2H_CPG_PLL_DSI_LIMITS(name)					\
+	static const struct rzv2h_pll_limits (name) = {			\
+		.fout = { .min = 25 * MEGA, .max = 375 * MEGA },	\
+		.fvco = { .min = 1600 * MEGA, .max = 3200 * MEGA },	\
+		.m = { .min = 64, .max = 533 },				\
+		.p = { .min = 1, .max = 4 },				\
+		.s = { .min = 0, .max = 6 },				\
+		.k = { .min = -32768, .max = 32767 },			\
+	}								\
+
+/**
+ * rzv2h_get_pll_pars - Finds the best combination of PLL parameters
+ * for a given frequency.
+ *
+ * @limits: Pointer to the structure containing the limits for the PLL parameters
+ * @pars: Pointer to the structure where the best calculated PLL parameters values
+ * will be stored
+ * @freq_millihz: Target output frequency in millihertz
+ *
+ * This function calculates the best set of PLL parameters (M, K, P, S) to achieve
+ * the desired frequency.
+ * There is no direct formula to calculate the PLL parameters, as it's an open
+ * system of equations, therefore this function uses an iterative approach to
+ * determine the best solution. The best solution is one that minimizes the error
+ * (desired frequency - actual frequency).
+ *
+ * Return: true if a valid set of parameters values is found, false otherwise.
+ */
+static __maybe_unused bool
+rzv2h_get_pll_pars(const struct rzv2h_pll_limits *limits,
+		   struct rzv2h_pll_pars *pars, u64 freq_millihz)
+{
+	u64 fout_min_millihz = mul_u32_u32(limits->fout.min, MILLI);
+	u64 fout_max_millihz = mul_u32_u32(limits->fout.max, MILLI);
+	struct rzv2h_pll_pars p, best;
+
+	if (freq_millihz > fout_max_millihz ||
+	    freq_millihz < fout_min_millihz)
+		return false;
+
+	/* Initialize best error to maximum possible value */
+	best.error_millihz = S64_MAX;
+
+	for (p.p = limits->p.min; p.p <= limits->p.max; p.p++) {
+		u32 fref = RZ_V2H_OSC_CLK_IN_MEGA / p.p;
+		u16 divider;
+
+		for (divider = 1 << limits->s.min, p.s = limits->s.min;
+			p.s <= limits->s.max; p.s++, divider <<= 1) {
+			for (p.m = limits->m.min; p.m <= limits->m.max; p.m++) {
+				u64 output_m, output_k_range;
+				s64 pll_k, output_k;
+				u64 fvco, output;
+
+				/*
+				 * The frequency generated by the PLL + divider
+				 * is calculated as follows:
+				 *
+				 * With:
+				 * Freq = Ffout = Ffvco / 2^(pll_s)
+				 * Ffvco = (pll_m + (pll_k / 65536)) * Ffref
+				 * Ffref = 24MHz / pll_p
+				 *
+				 * Freq can also be rewritten as:
+				 * Freq = Ffvco / 2^(pll_s)
+				 *      = ((pll_m + (pll_k / 65536)) * Ffref) / 2^(pll_s)
+				 *      = (pll_m * Ffref) / 2^(pll_s) + ((pll_k / 65536) * Ffref) / 2^(pll_s)
+				 *      = output_m + output_k
+				 *
+				 * Every parameter has been determined at this
+				 * point, but pll_k.
+				 *
+				 * Considering that:
+				 * limits->k.min <= pll_k <= limits->k.max
+				 * Then:
+				 * -0.5 <= (pll_k / 65536) < 0.5
+				 * Therefore:
+				 * -Ffref / (2 * 2^(pll_s)) <= output_k < Ffref / (2 * 2^(pll_s))
+				 */
+
+				/* Compute output M component (in mHz) */
+				output_m = DIV_ROUND_CLOSEST_ULL(mul_u32_u32(p.m, fref) * MILLI,
+								 divider);
+				/* Compute range for output K (in mHz) */
+				output_k_range = DIV_ROUND_CLOSEST_ULL(mul_u32_u32(fref, MILLI),
+								       2 * divider);
+				/*
+				 * No point in continuing if we can't achieve
+				 * the desired frequency
+				 */
+				if (freq_millihz <  (output_m - output_k_range) ||
+				    freq_millihz >= (output_m + output_k_range)) {
+					continue;
+				}
+
+				/*
+				 * Compute the K component
+				 *
+				 * Since:
+				 * Freq = output_m + output_k
+				 * Then:
+				 * output_k = Freq - output_m
+				 *          = ((pll_k / 65536) * Ffref) / 2^(pll_s)
+				 * Therefore:
+				 * pll_k = (output_k * 65536 * 2^(pll_s)) / Ffref
+				 */
+				output_k = freq_millihz - output_m;
+				pll_k = div_s64(output_k * 65536ULL * divider,
+						fref);
+				pll_k = DIV_S64_ROUND_CLOSEST(pll_k, MILLI);
+
+				/* Validate K value within allowed limits */
+				if (pll_k < limits->k.min ||
+				    pll_k > limits->k.max)
+					continue;
+
+				p.k = pll_k;
+
+				/* Compute (Ffvco * 65536) */
+				fvco = mul_u32_u32(p.m * 65536 + p.k, fref);
+				if (fvco < mul_u32_u32(limits->fvco.min, 65536) ||
+				    fvco > mul_u32_u32(limits->fvco.max, 65536))
+					continue;
+
+				/* PLL_M component of (output * 65536 * PLL_P) */
+				output = mul_u32_u32(p.m * 65536, RZ_V2H_OSC_CLK_IN_MEGA);
+				/* PLL_K component of (output * 65536 * PLL_P) */
+				output += p.k * RZ_V2H_OSC_CLK_IN_MEGA;
+				/* Make it in mHz */
+				output *= MILLI;
+				output = DIV_U64_ROUND_CLOSEST(output, 65536 * p.p * divider);
+
+				/* Check output frequency against limits */
+				if (output < fout_min_millihz ||
+				    output > fout_max_millihz)
+					continue;
+
+				p.error_millihz = freq_millihz - output;
+				p.freq_millihz = output;
+
+				/* If an exact match is found, return immediately */
+				if (p.error_millihz == 0) {
+					*pars = p;
+					return true;
+				}
+
+				/* Update best match if error is smaller */
+				if (abs(best.error_millihz) > abs(p.error_millihz))
+					best = p;
+			}
+		}
+	}
+
+	/* If no valid parameters were found, return false */
+	if (best.error_millihz == S64_MAX)
+		return false;
+
+	*pars = best;
+	return true;
+}
+
+/*
+ * rzv2h_get_pll_div_pars - Finds the best combination of PLL parameters
+ * and divider value for a given frequency.
+ *
+ * @limits: Pointer to the structure containing the limits for the PLL parameters
+ * @pars: Pointer to the structure where the best calculated PLL parameters and
+ * divider values will be stored
+ * @divider: Divider value to be applied to the PLL output
+ * @freq_millihz: Target output frequency in millihertz
+ *
+ * This function calculates the best set of PLL parameters (M, K, P, S) where
+ * the divider value is already known. See rzv2h_get_pll_pars() for more details
+ * on how the PLL parameters are calculated.
+ */
+static __maybe_unused bool
+rzv2h_get_pll_div_pars(const struct rzv2h_pll_limits *limits,
+		       struct rzv2h_pll_div_pars *pars, u8 divider,
+		       u64 freq_millihz)
+{
+	if (!rzv2h_get_pll_pars(limits, &pars->pll, freq_millihz * divider))
+		return false;
+
+	pars->div.divider_value = divider;
+	pars->div.freq_millihz = DIV_U64_ROUND_CLOSEST(pars->pll.freq_millihz, divider);
+	pars->div.error_millihz = freq_millihz - pars->div.freq_millihz;
+
+	return true;
+}
+
+/*
+ * rzv2h_get_pll_divs_pars - Finds the best combination of PLL parameters
+ * and divider value for a given frequency.
+ *
+ * @limits: Pointer to the structure containing the limits for the PLL parameters
+ * @pars: Pointer to the structure where the best calculated PLL parameters and
+ * divider values will be stored
+ * @table: Pointer to the array of valid divider values
+ * @table_size: Size of the divider values array
+ * @freq_millihz: Target output frequency in millihertz
+ *
+ * This function calculates the best set of PLL parameters (M, K, P, S) and divider
+ * value to achieve the desired frequency. See rzv2h_get_pll_pars() for more details
+ * on how the PLL parameters are calculated.
+ *
+ * freq_millihz is the desired frequency generated by the PLL followed by a
+ * a gear.
+ */
+static __maybe_unused bool
+rzv2h_get_pll_divs_pars(const struct rzv2h_pll_limits *limits,
+			struct rzv2h_pll_div_pars *pars,
+			const u8 *table, u8 table_size, u64 freq_millihz)
+{
+	struct rzv2h_pll_div_pars p, best;
+
+	best.div.error_millihz = S64_MAX;
+	p.div.error_millihz = S64_MAX;
+	for (unsigned int i = 0; i < table_size; i++) {
+		if (!rzv2h_get_pll_div_pars(limits, &p, table[i], freq_millihz))
+			continue;
+
+		if (p.div.error_millihz == 0) {
+			*pars = p;
+			return true;
+		}
+
+		if (abs(best.div.error_millihz) > abs(p.div.error_millihz))
+			best = p;
+	}
+
+	if (best.div.error_millihz == S64_MAX)
+		return false;
+
+	*pars = best;
+	return true;
+}
+
+/*
+ * rzv2h_get_pll_dtable_pars - Finds the best combination of PLL parameters
+ * and divider value for a given frequency using a divider table.
+ *
+ * @limits: Pointer to the structure containing the limits for the PLL parameters
+ * @pars: Pointer to the structure where the best calculated PLL parameters and
+ * divider values will be stored
+ * @dtable: Pointer to the array of valid divider values
+ * @freq_millihz: Target output frequency in millihertz
+ *
+ * See rzv2h_get_pll_divs_pars() for more details on how the PLL
+ * parameters and divider values are calculated.
+ */
+static __maybe_unused bool
+rzv2h_get_pll_dtable_pars(const struct rzv2h_pll_limits *limits,
+			  struct rzv2h_pll_div_pars *pars,
+			  const struct clk_div_table *dtable, u64 freq_millihz)
+{
+	const struct clk_div_table *div = dtable;
+	u8 table[RZV2H_MAX_DIV_TABLES] = { 0 };
+	unsigned int i = 0;
+
+	for (; div->div; div++) {
+		if (i >= RZV2H_MAX_DIV_TABLES)
+			return false;
+		table[i++] = div->div;
+	}
+
+	return rzv2h_get_pll_divs_pars(limits, pars, table, i, freq_millihz);
+}
+
+#endif	/* __RENESAS_RZV2H_CPG_PLL_H__ */
-- 
2.50.1

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