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* [PATCH v5 0/4] Add support for DU/DSI clocks and DSI driver support for the Renesas RZ/V2H(P) SoC
@ 2025-05-12 18:42 Prabhakar
  2025-05-12 18:42 ` [PATCH v5 1/4] clk: renesas: rzv2h-cpg: Add support for DSI clocks Prabhakar
                   ` (3 more replies)
  0 siblings, 4 replies; 18+ messages in thread
From: Prabhakar @ 2025-05-12 18:42 UTC (permalink / raw)
  To: Andrzej Hajda, Neil Armstrong, Robert Foss, Laurent Pinchart,
	Jonas Karlman, Jernej Skrabec, David Airlie, Simona Vetter,
	Maarten Lankhorst, Maxime Ripard, Thomas Zimmermann, Rob Herring,
	Krzysztof Kozlowski, Conor Dooley, Geert Uytterhoeven,
	Michael Turquette, Stephen Boyd, Biju Das, Magnus Damm
  Cc: dri-devel, devicetree, linux-kernel, linux-renesas-soc, linux-clk,
	Prabhakar, Fabrizio Castro, Lad Prabhakar

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

Hi All,

This patch series adds DU/DSI clocks and provides support for the
MIPI DSI interface on the RZ/V2H(P) SoC. It was originally part of
series [0], but has now been split into 4 patches due to dependencies
on the clock driver, making it easier to review and merge.

[0] https://lore.kernel.org/all/20250430204112.342123-1-prabhakar.mahadev-lad.rj@bp.renesas.com/

Note: This patch series applies on top of the following patch series:
[1] https://lore.kernel.org/all/20250512182330.238259-1-prabhakar.mahadev-lad.rj@bp.renesas.com/

Cheers,
Prabhakar

Lad Prabhakar (4):
  clk: renesas: rzv2h-cpg: Add support for DSI clocks
  clk: renesas: r9a09g057: Add clock and reset entries for DSI and LCDC
  dt-bindings: display: bridge: renesas,dsi: Add support for RZ/V2H(P)
    SoC
  drm: renesas: rz-du: mipi_dsi: Add support for RZ/V2H(P) SoC

 .../bindings/display/bridge/renesas,dsi.yaml  | 116 ++++--
 drivers/clk/renesas/r9a09g057-cpg.c           |  63 ++++
 drivers/clk/renesas/rzv2h-cpg.c               | 237 +++++++++++-
 drivers/clk/renesas/rzv2h-cpg.h               |  17 +
 .../gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c    | 343 ++++++++++++++++++
 .../drm/renesas/rz-du/rzg2l_mipi_dsi_regs.h   |  34 ++
 include/linux/clk/renesas-rzv2h-dsi.h         | 211 +++++++++++
 7 files changed, 990 insertions(+), 31 deletions(-)
 create mode 100644 include/linux/clk/renesas-rzv2h-dsi.h

-- 
2.49.0


^ permalink raw reply	[flat|nested] 18+ messages in thread

* [PATCH v5 1/4] clk: renesas: rzv2h-cpg: Add support for DSI clocks
  2025-05-12 18:42 [PATCH v5 0/4] Add support for DU/DSI clocks and DSI driver support for the Renesas RZ/V2H(P) SoC Prabhakar
@ 2025-05-12 18:42 ` Prabhakar
  2025-05-20  6:19   ` Biju Das
  2025-05-23 14:45   ` Geert Uytterhoeven
  2025-05-12 18:43 ` [PATCH v5 2/4] clk: renesas: r9a09g057: Add clock and reset entries for DSI and LCDC Prabhakar
                   ` (2 subsequent siblings)
  3 siblings, 2 replies; 18+ messages in thread
From: Prabhakar @ 2025-05-12 18:42 UTC (permalink / raw)
  To: Andrzej Hajda, Neil Armstrong, Robert Foss, Laurent Pinchart,
	Jonas Karlman, Jernej Skrabec, David Airlie, Simona Vetter,
	Maarten Lankhorst, Maxime Ripard, Thomas Zimmermann, Rob Herring,
	Krzysztof Kozlowski, Conor Dooley, Geert Uytterhoeven,
	Michael Turquette, Stephen Boyd, Biju Das, Magnus Damm
  Cc: dri-devel, devicetree, linux-kernel, linux-renesas-soc, linux-clk,
	Prabhakar, Fabrizio Castro, Lad Prabhakar

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

Add support for PLLDSI and PLLDSI divider clocks.

Introduce the `renesas-rzv2h-dsi.h` header to centralize and share
PLLDSI-related data structures, limits, and algorithms between the RZ/V2H
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@renesas.com>
Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
---
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       | 237 +++++++++++++++++++++++++-
 drivers/clk/renesas/rzv2h-cpg.h       |  14 ++
 include/linux/clk/renesas-rzv2h-dsi.h | 211 +++++++++++++++++++++++
 3 files changed, 460 insertions(+), 2 deletions(-)
 create mode 100644 include/linux/clk/renesas-rzv2h-dsi.h

diff --git a/drivers/clk/renesas/rzv2h-cpg.c b/drivers/clk/renesas/rzv2h-cpg.c
index 882e301c2d1b..ccf6a664e71d 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-dsi.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>
 
@@ -48,6 +53,7 @@
 #define CPG_PLL_STBY(x)		((x))
 #define CPG_PLL_STBY_RESETB	BIT(0)
 #define CPG_PLL_STBY_RESETB_WEN	BIT(16)
+#define CPG_PLL_STBY_SSCGEN_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))
@@ -79,6 +85,8 @@
  * @last_dt_core_clk: ID of the last Core Clock exported to DT
  * @mstop_count: Array of mstop values
  * @rcdev: Reset controller entity
+ * @dsi_limits: PLL DSI parameters limits
+ * @plldsi_div_parameters: PLL DSI and divider parameters configuration
  */
 struct rzv2h_cpg_priv {
 	struct device *dev;
@@ -95,6 +103,9 @@ struct rzv2h_cpg_priv {
 	atomic_t *mstop_count;
 
 	struct reset_controller_dev rcdev;
+
+	const struct rzv2h_pll_div_limits *dsi_limits;
+	struct rzv2h_plldsi_parameters plldsi_div_parameters;
 };
 
 #define rcdev_to_priv(x)	container_of(x, struct rzv2h_cpg_priv, rcdev)
@@ -150,6 +161,24 @@ struct ddiv_clk {
 
 #define to_ddiv_clock(_div) container_of(_div, struct ddiv_clk, div)
 
+/**
+ * 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 int rzv2h_cpg_pll_clk_is_enabled(struct clk_hw *hw)
 {
 	struct pll_clk *pll_clk = to_pll(hw);
@@ -198,6 +227,188 @@ static int rzv2h_cpg_pll_clk_enable(struct clk_hw *hw)
 	return ret;
 }
 
+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 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_plldsi_parameters *dsi_dividers = &priv->plldsi_div_parameters;
+	u64 rate_millihz;
+
+	/*
+	 * Adjust the requested clock rate (`req->rate`) to ensure it falls within
+	 * the supported range of 5.44 MHz to 187.5 MHz.
+	 */
+	req->rate = clamp(req->rate, 5440000UL, 187500000UL);
+
+	rate_millihz = mul_u32_u32(req->rate, MILLI);
+	if (rate_millihz == dsi_dividers->error_millihz + dsi_dividers->freq_millihz)
+		goto exit_determine_rate;
+
+	if (!rzv2h_dsi_get_pll_parameters_values(priv->dsi_limits,
+						 dsi_dividers, rate_millihz)) {
+		dev_err(priv->dev,
+			"failed to determine rate for req->rate: %lu\n",
+			req->rate);
+		return -EINVAL;
+	}
+
+exit_determine_rate:
+	req->best_parent_rate = req->rate * dsi_dividers->csdiv;
+
+	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_plldsi_parameters *dsi_dividers = &priv->plldsi_div_parameters;
+	struct ddiv ddiv = dsi_div->ddiv;
+	const struct clk_div_table *clkt;
+	bool div_found = false;
+	u32 val, shift, div;
+
+	div = dsi_dividers->csdiv;
+	for (clkt = dsi_div->dtable; clkt->div; clkt++) {
+		if (clkt->div == div) {
+			div_found = true;
+			break;
+		}
+	}
+
+	if (!div_found)
+		return -EINVAL;
+
+	shift = ddiv.shift;
+	val = readl(priv->base + ddiv.offset) | DDIV_DIVCTL_WEN(shift);
+	val &= ~(clk_div_mask(ddiv.width) << shift);
+	val |= (u32)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 long rzv2h_cpg_plldsi_round_rate(struct clk_hw *hw,
+					unsigned long rate,
+					unsigned long *parent_rate)
+{
+	return clamp(rate, 25000000UL, 375000000UL);
+}
+
+static int rzv2h_cpg_pll_set_rate(struct clk_hw *hw,
+				  unsigned long rate,
+				  unsigned long parent_rate)
+{
+	struct pll_clk *pll_clk = to_pll(hw);
+	struct rzv2h_cpg_priv *priv = pll_clk->priv;
+	struct rzv2h_plldsi_parameters *dsi_dividers;
+	struct pll pll = pll_clk->pll;
+	u16 offset = 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;
+	}
+
+	dsi_dividers = &priv->plldsi_div_parameters;
+	/* Output clock setting 1 */
+	writel((dsi_dividers->k << 16) | (dsi_dividers->m << 6) | (dsi_dividers->p),
+	       priv->base + CPG_PLL_CLK1(offset));
+
+	/* Output clock setting 2 */
+	val = readl(priv->base + CPG_PLL_CLK2(offset));
+	writel((val & ~GENMASK(2, 0)) | dsi_dividers->s,
+	       priv->base + CPG_PLL_CLK2(offset));
+
+	/* Put PLL to normal mode */
+	writel(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 unsigned long rzv2h_cpg_pll_clk_recalc_rate(struct clk_hw *hw,
 						   unsigned long parent_rate)
 {
@@ -219,6 +430,12 @@ static unsigned long rzv2h_cpg_pll_clk_recalc_rate(struct clk_hw *hw,
 	return DIV_ROUND_CLOSEST_ULL(rate, CPG_PLL_CLK1_PDIV(clk1));
 }
 
+static const struct clk_ops rzv2h_cpg_plldsi_ops = {
+	.recalc_rate = rzv2h_cpg_pll_clk_recalc_rate,
+	.round_rate = rzv2h_cpg_plldsi_round_rate,
+	.set_rate = rzv2h_cpg_pll_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,
@@ -228,7 +445,8 @@ 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 turn_on)
 {
 	void __iomem *base = priv->base;
 	struct device *dev = priv->dev;
@@ -258,6 +476,13 @@ rzv2h_cpg_pll_clk_register(const struct cpg_core_clk *core,
 	pll_clk->base = base;
 	pll_clk->priv = priv;
 
+	if (turn_on) {
+		/* Disable SSC and turn on PLL clock when init */
+		writel(CPG_PLL_STBY_RESETB_WEN | CPG_PLL_STBY_RESETB |
+		       CPG_PLL_STBY_SSCGEN_WEN,
+		       base + CPG_PLL_STBY(pll_clk->pll.offset));
+	}
+
 	ret = devm_clk_hw_register(dev, &pll_clk->hw);
 	if (ret)
 		return ERR_PTR(ret);
@@ -499,7 +724,7 @@ rzv2h_cpg_register_core_clk(const struct cpg_core_clk *core,
 			clk = clk_hw->clk;
 		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);
@@ -507,6 +732,12 @@ 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;
 	}
@@ -1043,6 +1274,8 @@ static int __init rzv2h_cpg_probe(struct platform_device *pdev)
 	priv->last_dt_core_clk = info->last_dt_core_clk;
 	priv->num_resets = info->num_resets;
 
+	priv->dsi_limits = info->plldsi_limits;
+
 	for (i = 0; i < nclks; i++)
 		clks[i] = ERR_PTR(-ENOENT);
 
diff --git a/drivers/clk/renesas/rzv2h-cpg.h b/drivers/clk/renesas/rzv2h-cpg.h
index cd6bcd4f2901..6f662fa86ac4 100644
--- a/drivers/clk/renesas/rzv2h-cpg.h
+++ b/drivers/clk/renesas/rzv2h-cpg.h
@@ -100,6 +100,7 @@ struct smuxed {
 #define CPG_CDDIV3		(0x40C)
 #define CPG_CDDIV4		(0x410)
 #define CPG_CSDIV0		(0x500)
+#define CPG_CSDIV1		(0x504)
 
 #define CDDIV0_DIVCTL1	DDIV_PACK(CPG_CDDIV0, 4, 3, 1)
 #define CDDIV0_DIVCTL2	DDIV_PACK(CPG_CDDIV0, 8, 3, 2)
@@ -168,6 +169,8 @@ 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...) \
@@ -195,6 +198,14 @@ 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
@@ -295,6 +306,7 @@ struct rzv2h_reset {
  *
  * @num_mstop_bits: Maximum number of MSTOP bits supported, equivalent to the
  *		    number of CPG_BUS_m_MSTOP registers multiplied by 16.
+ * @plldsi_limits: PLL DSI parameters limits
  */
 struct rzv2h_cpg_info {
 	/* Core Clocks */
@@ -313,6 +325,8 @@ struct rzv2h_cpg_info {
 	unsigned int num_resets;
 
 	unsigned int num_mstop_bits;
+
+	const struct rzv2h_pll_div_limits *plldsi_limits;
 };
 
 extern const struct rzv2h_cpg_info r9a09g047_cpg_info;
diff --git a/include/linux/clk/renesas-rzv2h-dsi.h b/include/linux/clk/renesas-rzv2h-dsi.h
new file mode 100644
index 000000000000..faecb5d49c20
--- /dev/null
+++ b/include/linux/clk/renesas-rzv2h-dsi.h
@@ -0,0 +1,211 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Renesas RZ/V2H(P) DSI CPG helper
+ *
+ * Copyright (C) 2025 Renesas Electronics Corp.
+ */
+#ifndef __RENESAS_RZV2H_DSI_H__
+#define __RENESAS_RZV2H_DSI_H__
+
+#include <linux/limits.h>
+#include <linux/math.h>
+#include <linux/math64.h>
+#include <linux/units.h>
+
+#define OSC_CLK_IN_MEGA		(24 * MEGA)
+
+struct rzv2h_pll_div_limits {
+	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 {
+		u8 min;
+		u8 max;
+	} csdiv;
+};
+
+struct rzv2h_plldsi_parameters {
+	u64 freq_millihz;
+	s64 error_millihz;
+	u16 m;
+	s16 k;
+	u8 csdiv;
+	u8 p;
+	u8 s;
+};
+
+#define RZV2H_CPG_PLL_DSI_LIMITS(name)					\
+	static const struct rzv2h_pll_div_limits (name) = {		\
+		.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 },			\
+		.csdiv = { .min = 2, .max = 32 },			\
+	}								\
+
+/**
+ * rzv2h_dsi_get_pll_parameters_values - 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 and
+ * divider values
+ * @pars: Pointer to the structure where the best calculated PLL parameters and divider
+ * values will be stored
+ * @freq_millihz: Target output frequency in millihertz
+ *
+ * This function calculates the best set of PLL parameters (M, K, P, S) and divider
+ * value (CSDIV) to achieve the desired frequency.
+ * There is no direct formula to calculate the PLL parameters and the divider value,
+ * 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 divider values is found, false otherwise.
+ */
+static __maybe_unused bool
+rzv2h_dsi_get_pll_parameters_values(const struct rzv2h_pll_div_limits *limits,
+				    struct rzv2h_plldsi_parameters *pars,
+				    u64 freq_millihz)
+{
+	struct rzv2h_plldsi_parameters p, best;
+
+	/* Initialize best error to maximum possible value */
+	best.error_millihz = S64_MAX;
+
+	for (p.csdiv = limits->csdiv.min; p.csdiv <= limits->csdiv.max; p.csdiv += 2) {
+		for (p.p = limits->p.min; p.p <= limits->p.max; p.p++) {
+			u32 fref = OSC_CLK_IN_MEGA / p.p;
+
+			for (p.s = limits->s.min; p.s <= limits->s.max; p.s++) {
+				u16 two_pow_s = 1 << p.s;
+				u16 divider = two_pow_s * p.csdiv;
+
+				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 combination of the
+					 * PLL + divider is calculated as follows:
+					 *
+					 * Freq = Ffout / csdiv
+					 *
+					 * With:
+					 * 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) * csdiv))
+					 *      = Ffvco / divider
+					 *      = (pll_m * Ffref) / divider + ((pll_k / 65536) * Ffref) / divider
+					 *      = output_m + output_k
+					 *
+					 * Every parameter has been determined at this point, but pll_k.
+					 * Considering that:
+					 * -32768 <= pll_k <= 32767
+					 * Then:
+					 * -0.5 <= (pll_k / 65536) < 0.5
+					 * Therefore:
+					 * -Ffref / (2 * divider) <= output_k < Ffref / (2 * divider)
+					 */
+
+					/* Compute output M component (in mHz) */
+					output_m = DIV_ROUND_CLOSEST_ULL(p.m * fref * 1000ULL,
+									 divider);
+					/* Compute range for output K (in mHz) */
+					output_k_range = DIV_ROUND_CLOSEST_ULL(fref * 1000ULL,
+									       divider * 2);
+					/*
+					 * 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) / divider
+					 * Therefore:
+					 * pll_k = (output_k * 65536 * divider) / Ffref
+					 */
+					output_k = freq_millihz - output_m;
+					pll_k = div64_s64(output_k * 65536ULL * divider, fref);
+					pll_k = DIV_S64_ROUND_CLOSEST(pll_k, 1000);
+
+					/* 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 = ((p.m * 65536ULL) + p.k) * fref;
+					if ((fvco < (limits->fvco.min * 65536ULL)) ||
+					    (fvco > (limits->fvco.max * 65536ULL)))
+						continue;
+
+					/* PLL_M component of (output * 65536 * PLL_P) */
+					output = p.m * 65536ULL * OSC_CLK_IN_MEGA;
+					/* PLL_K component of (output * 65536 * PLL_P) */
+					output += p.k * OSC_CLK_IN_MEGA;
+					/* Make it in mHz */
+					output *= 1000ULL;
+					output /= 65536ULL * p.p * divider;
+
+					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;
+}
+
+#endif	/* __RENESAS_RZV2H_DSI_H__ */
-- 
2.49.0


^ permalink raw reply related	[flat|nested] 18+ messages in thread

* [PATCH v5 2/4] clk: renesas: r9a09g057: Add clock and reset entries for DSI and LCDC
  2025-05-12 18:42 [PATCH v5 0/4] Add support for DU/DSI clocks and DSI driver support for the Renesas RZ/V2H(P) SoC Prabhakar
  2025-05-12 18:42 ` [PATCH v5 1/4] clk: renesas: rzv2h-cpg: Add support for DSI clocks Prabhakar
@ 2025-05-12 18:43 ` Prabhakar
  2025-05-23 14:46   ` Geert Uytterhoeven
  2025-05-12 18:43 ` [PATCH v5 3/4] dt-bindings: display: bridge: renesas, dsi: Add support for RZ/V2H(P) SoC Prabhakar
  2025-05-12 18:43 ` [PATCH v5 4/4] drm: renesas: rz-du: mipi_dsi: " Prabhakar
  3 siblings, 1 reply; 18+ messages in thread
From: Prabhakar @ 2025-05-12 18:43 UTC (permalink / raw)
  To: Andrzej Hajda, Neil Armstrong, Robert Foss, Laurent Pinchart,
	Jonas Karlman, Jernej Skrabec, David Airlie, Simona Vetter,
	Maarten Lankhorst, Maxime Ripard, Thomas Zimmermann, Rob Herring,
	Krzysztof Kozlowski, Conor Dooley, Geert Uytterhoeven,
	Michael Turquette, Stephen Boyd, Biju Das, Magnus Damm
  Cc: dri-devel, devicetree, linux-kernel, linux-renesas-soc, linux-clk,
	Prabhakar, Fabrizio Castro, Lad Prabhakar

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

Add clock and reset entries for the DSI and LCDC peripherals.

Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
---
v4->v5:
- No changes

v3->v4:
- No changes

v2->v3:
- Reverted CSDIV0_DIVCTL2() to use DDIV_PACK()
- Renamed plleth_lpclk_div4 -> cdiv4_plleth_lpclk
- Renamed plleth_lpclk -> plleth_lpclk_gear

v1->v2:
- Changed CSDIV0_DIVCTL2 to the NO_RMW
---
 drivers/clk/renesas/r9a09g057-cpg.c | 63 +++++++++++++++++++++++++++++
 drivers/clk/renesas/rzv2h-cpg.h     |  3 ++
 2 files changed, 66 insertions(+)

diff --git a/drivers/clk/renesas/r9a09g057-cpg.c b/drivers/clk/renesas/r9a09g057-cpg.c
index da908e820950..a79b67181f11 100644
--- a/drivers/clk/renesas/r9a09g057-cpg.c
+++ b/drivers/clk/renesas/r9a09g057-cpg.c
@@ -6,6 +6,7 @@
  */
 
 #include <linux/clk-provider.h>
+#include <linux/clk/renesas-rzv2h-dsi.h>
 #include <linux/device.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
@@ -30,6 +31,7 @@ enum clk_ids {
 	CLK_PLLCA55,
 	CLK_PLLVDO,
 	CLK_PLLETH,
+	CLK_PLLDSI,
 	CLK_PLLGPU,
 
 	/* Internal Core Clocks */
@@ -58,6 +60,9 @@ enum clk_ids {
 	CLK_SMUX2_GBE0_RXCLK,
 	CLK_SMUX2_GBE1_TXCLK,
 	CLK_SMUX2_GBE1_RXCLK,
+	CLK_DIV_PLLETH_LPCLK,
+	CLK_CSDIV_PLLETH_LPCLK,
+	CLK_PLLDSI_SDIV2,
 	CLK_PLLGPU_GEAR,
 
 	/* Module Clocks */
@@ -78,6 +83,26 @@ static const struct clk_div_table dtable_2_4[] = {
 	{0, 0},
 };
 
+static const struct clk_div_table dtable_2_32[] = {
+	{0, 2},
+	{1, 4},
+	{2, 6},
+	{3, 8},
+	{4, 10},
+	{5, 12},
+	{6, 14},
+	{7, 16},
+	{8, 18},
+	{9, 20},
+	{10, 22},
+	{11, 24},
+	{12, 26},
+	{13, 28},
+	{14, 30},
+	{15, 32},
+	{0, 0},
+};
+
 static const struct clk_div_table dtable_2_64[] = {
 	{0, 2},
 	{1, 4},
@@ -94,6 +119,14 @@ static const struct clk_div_table dtable_2_100[] = {
 	{0, 0},
 };
 
+static const struct clk_div_table dtable_16_128[] = {
+	{0, 16},
+	{1, 32},
+	{2, 64},
+	{3, 128},
+	{0, 0},
+};
+
 /* Mux clock tables */
 static const char * const smux2_gbe0_rxclk[] = { ".plleth_gbe0", "et0_rxclk" };
 static const char * const smux2_gbe0_txclk[] = { ".plleth_gbe0", "et0_txclk" };
@@ -113,6 +146,7 @@ static const struct cpg_core_clk r9a09g057_core_clks[] __initconst = {
 	DEF_PLL(".pllca55", CLK_PLLCA55, CLK_QEXTAL, PLLCA55),
 	DEF_FIXED(".pllvdo", CLK_PLLVDO, CLK_QEXTAL, 105, 2),
 	DEF_FIXED(".plleth", CLK_PLLETH, CLK_QEXTAL, 125, 3),
+	DEF_PLLDSI(".plldsi", CLK_PLLDSI, CLK_QEXTAL, PLLDSI),
 	DEF_PLL(".pllgpu", CLK_PLLGPU, CLK_QEXTAL, PLLGPU),
 
 	/* Internal Core Clocks */
@@ -148,6 +182,12 @@ static const struct cpg_core_clk r9a09g057_core_clks[] __initconst = {
 	DEF_SMUX(".smux2_gbe0_rxclk", CLK_SMUX2_GBE0_RXCLK, SSEL0_SELCTL3, smux2_gbe0_rxclk),
 	DEF_SMUX(".smux2_gbe1_txclk", CLK_SMUX2_GBE1_TXCLK, SSEL1_SELCTL0, smux2_gbe1_txclk),
 	DEF_SMUX(".smux2_gbe1_rxclk", CLK_SMUX2_GBE1_RXCLK, SSEL1_SELCTL1, smux2_gbe1_rxclk),
+	DEF_FIXED(".cdiv4_plleth_lpclk", CLK_DIV_PLLETH_LPCLK, CLK_PLLETH, 1, 4),
+	DEF_CSDIV(".plleth_lpclk_gear", CLK_CSDIV_PLLETH_LPCLK, CLK_DIV_PLLETH_LPCLK,
+		  CSDIV0_DIVCTL2, dtable_16_128),
+
+	DEF_PLLDSI_DIV(".plldsi_sdiv2", CLK_PLLDSI_SDIV2, CLK_PLLDSI,
+		       CSDIV1_DIVCTL2, dtable_2_32),
 
 	DEF_DDIV(".pllgpu_gear", CLK_PLLGPU_GEAR, CLK_PLLGPU, CDDIV3_DIVCTL1, dtable_2_64),
 
@@ -319,6 +359,22 @@ static const struct rzv2h_mod_clk r9a09g057_mod_clks[] __initconst = {
 						BUS_MSTOP(9, BIT(7))),
 	DEF_MOD("cru_3_pclk",			CLK_PLLDTY_DIV16, 13, 13, 6, 29,
 						BUS_MSTOP(9, BIT(7))),
+	DEF_MOD("dsi_0_pclk",			CLK_PLLDTY_DIV16, 14, 8, 7, 8,
+						BUS_MSTOP(9, BIT(14) | BIT(15))),
+	DEF_MOD("dsi_0_aclk",			CLK_PLLDTY_ACPU_DIV2, 14, 9, 7, 9,
+						BUS_MSTOP(9, BIT(14) | BIT(15))),
+	DEF_MOD("dsi_0_vclk1",			CLK_PLLDSI_SDIV2, 14, 10, 7, 10,
+						BUS_MSTOP(9, BIT(14) | BIT(15))),
+	DEF_MOD("dsi_0_lpclk",			CLK_CSDIV_PLLETH_LPCLK, 14, 11, 7, 11,
+						BUS_MSTOP(9, BIT(14) | BIT(15))),
+	DEF_MOD("dsi_0_pllref_clk",		CLK_QEXTAL, 14, 12, 7, 12,
+						BUS_MSTOP(9, BIT(14) | BIT(15))),
+	DEF_MOD("lcdc_0_clk_a",			CLK_PLLDTY_ACPU_DIV2, 14, 13, 7, 13,
+						BUS_MSTOP(10, BIT(1) | BIT(2) | BIT(3))),
+	DEF_MOD("lcdc_0_clk_p",			CLK_PLLDTY_DIV16, 14, 14, 7, 14,
+						BUS_MSTOP(10, BIT(1) | BIT(2) | BIT(3))),
+	DEF_MOD("lcdc_0_clk_d",			CLK_PLLDSI_SDIV2, 14, 15, 7, 15,
+						BUS_MSTOP(10, BIT(1) | BIT(2) | BIT(3))),
 	DEF_MOD("gpu_0_clk",			CLK_PLLGPU_GEAR, 15, 0, 7, 16,
 						BUS_MSTOP(3, BIT(4))),
 	DEF_MOD("gpu_0_axi_clk",		CLK_PLLDTY_ACPU_DIV2, 15, 1, 7, 17,
@@ -380,11 +436,16 @@ static const struct rzv2h_reset r9a09g057_resets[] __initconst = {
 	DEF_RST(12, 14, 5, 31),		/* CRU_3_PRESETN */
 	DEF_RST(12, 15, 6, 0),		/* CRU_3_ARESETN */
 	DEF_RST(13, 0, 6, 1),		/* CRU_3_S_RESETN */
+	DEF_RST(13, 7, 6, 8),		/* DSI_0_PRESETN */
+	DEF_RST(13, 8, 6, 9),		/* DSI_0_ARESETN */
+	DEF_RST(13, 12, 6, 13),		/* LCDC_0_RESET_N */
 	DEF_RST(13, 13, 6, 14),		/* GPU_0_RESETN */
 	DEF_RST(13, 14, 6, 15),		/* GPU_0_AXI_RESETN */
 	DEF_RST(13, 15, 6, 16),		/* GPU_0_ACE_RESETN */
 };
 
+RZV2H_CPG_PLL_DSI_LIMITS(rzv2h_cpg_pll_dsi_limits);
+
 const struct rzv2h_cpg_info r9a09g057_cpg_info __initconst = {
 	/* Core Clocks */
 	.core_clks = r9a09g057_core_clks,
@@ -402,4 +463,6 @@ const struct rzv2h_cpg_info r9a09g057_cpg_info __initconst = {
 	.num_resets = ARRAY_SIZE(r9a09g057_resets),
 
 	.num_mstop_bits = 192,
+
+	.plldsi_limits = &rzv2h_cpg_pll_dsi_limits,
 };
diff --git a/drivers/clk/renesas/rzv2h-cpg.h b/drivers/clk/renesas/rzv2h-cpg.h
index 6f662fa86ac4..e7570db1ccf5 100644
--- a/drivers/clk/renesas/rzv2h-cpg.h
+++ b/drivers/clk/renesas/rzv2h-cpg.h
@@ -28,6 +28,7 @@ struct pll {
 	})
 
 #define PLLCA55		PLL_PACK(0x60, 1)
+#define PLLDSI		PLL_PACK(0xc0, 1)
 #define PLLGPU		PLL_PACK(0x120, 1)
 
 /**
@@ -122,6 +123,8 @@ struct smuxed {
 
 #define CSDIV0_DIVCTL0	DDIV_PACK(CPG_CSDIV0, 0, 2, CSDIV_NO_MON)
 #define CSDIV0_DIVCTL1	DDIV_PACK(CPG_CSDIV0, 4, 2, CSDIV_NO_MON)
+#define CSDIV0_DIVCTL2	DDIV_PACK(CPG_CSDIV0, 8, 2, CSDIV_NO_MON)
+#define CSDIV1_DIVCTL2	DDIV_PACK(CPG_CSDIV1, 8, 4, CSDIV_NO_MON)
 
 #define SSEL0_SELCTL2	SMUX_PACK(CPG_SSEL0, 8, 1)
 #define SSEL0_SELCTL3	SMUX_PACK(CPG_SSEL0, 12, 1)
-- 
2.49.0


^ permalink raw reply related	[flat|nested] 18+ messages in thread

* [PATCH v5 3/4] dt-bindings: display: bridge: renesas, dsi: Add support for RZ/V2H(P) SoC
  2025-05-12 18:42 [PATCH v5 0/4] Add support for DU/DSI clocks and DSI driver support for the Renesas RZ/V2H(P) SoC Prabhakar
  2025-05-12 18:42 ` [PATCH v5 1/4] clk: renesas: rzv2h-cpg: Add support for DSI clocks Prabhakar
  2025-05-12 18:43 ` [PATCH v5 2/4] clk: renesas: r9a09g057: Add clock and reset entries for DSI and LCDC Prabhakar
@ 2025-05-12 18:43 ` Prabhakar
  2025-05-23 14:58   ` [PATCH v5 3/4] dt-bindings: display: bridge: renesas,dsi: " Geert Uytterhoeven
  2025-05-12 18:43 ` [PATCH v5 4/4] drm: renesas: rz-du: mipi_dsi: " Prabhakar
  3 siblings, 1 reply; 18+ messages in thread
From: Prabhakar @ 2025-05-12 18:43 UTC (permalink / raw)
  To: Andrzej Hajda, Neil Armstrong, Robert Foss, Laurent Pinchart,
	Jonas Karlman, Jernej Skrabec, David Airlie, Simona Vetter,
	Maarten Lankhorst, Maxime Ripard, Thomas Zimmermann, Rob Herring,
	Krzysztof Kozlowski, Conor Dooley, Geert Uytterhoeven,
	Michael Turquette, Stephen Boyd, Biju Das, Magnus Damm
  Cc: dri-devel, devicetree, linux-kernel, linux-renesas-soc, linux-clk,
	Prabhakar, Fabrizio Castro, Lad Prabhakar, Krzysztof Kozlowski

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

The MIPI DSI interface on the RZ/V2H(P) SoC is nearly identical to that of
the RZ/G2L SoC. While the LINK registers are the same for both SoCs, the
D-PHY registers differ. Additionally, the number of resets for DSI on
RZ/V2H(P) is two compared to three on the RZ/G2L.

To accommodate these differences, a SoC-specific
`renesas,r9a09g057-mipi-dsi` compatible string has been added for the
RZ/V2H(P) SoC.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
---
v4->v5:
- No changes

v3->v4:
- No changes

v2->v3:
- Collected reviewed tag from Krzysztof

v1->v2:
- Kept the sort order for schema validation
- Added  `port@1: false` for RZ/V2H(P) SoC
---
 .../bindings/display/bridge/renesas,dsi.yaml  | 116 +++++++++++++-----
 1 file changed, 87 insertions(+), 29 deletions(-)

diff --git a/Documentation/devicetree/bindings/display/bridge/renesas,dsi.yaml b/Documentation/devicetree/bindings/display/bridge/renesas,dsi.yaml
index e08c24633926..5980df2b389b 100644
--- a/Documentation/devicetree/bindings/display/bridge/renesas,dsi.yaml
+++ b/Documentation/devicetree/bindings/display/bridge/renesas,dsi.yaml
@@ -14,16 +14,17 @@ description: |
   RZ/G2L alike family of SoC's. The encoder can operate in DSI mode, with
   up to four data lanes.
 
-allOf:
-  - $ref: /schemas/display/dsi-controller.yaml#
-
 properties:
   compatible:
-    items:
+    oneOf:
       - enum:
-          - renesas,r9a07g044-mipi-dsi # RZ/G2{L,LC}
-          - renesas,r9a07g054-mipi-dsi # RZ/V2L
-      - const: renesas,rzg2l-mipi-dsi
+          - renesas,r9a09g057-mipi-dsi # RZ/V2H(P)
+
+      - items:
+          - enum:
+              - renesas,r9a07g044-mipi-dsi # RZ/G2{L,LC}
+              - renesas,r9a07g054-mipi-dsi # RZ/V2L
+          - const: renesas,rzg2l-mipi-dsi
 
   reg:
     maxItems: 1
@@ -49,34 +50,56 @@ properties:
       - const: debug
 
   clocks:
-    items:
-      - description: DSI D-PHY PLL multiplied clock
-      - description: DSI D-PHY system clock
-      - description: DSI AXI bus clock
-      - description: DSI Register access clock
-      - description: DSI Video clock
-      - description: DSI D-PHY Escape mode transmit clock
+    oneOf:
+      - items:
+          - description: DSI D-PHY PLL multiplied clock
+          - description: DSI D-PHY system clock
+          - description: DSI AXI bus clock
+          - description: DSI Register access clock
+          - description: DSI Video clock
+          - description: DSI D-PHY Escape mode transmit clock
+      - items:
+          - description: DSI D-PHY PLL multiplied clock
+          - description: DSI AXI bus clock
+          - description: DSI Register access clock
+          - description: DSI Video clock
+          - description: DSI D-PHY Escape mode transmit clock
 
   clock-names:
-    items:
-      - const: pllclk
-      - const: sysclk
-      - const: aclk
-      - const: pclk
-      - const: vclk
-      - const: lpclk
+    oneOf:
+      - items:
+          - const: pllclk
+          - const: sysclk
+          - const: aclk
+          - const: pclk
+          - const: vclk
+          - const: lpclk
+      - items:
+          - const: pllclk
+          - const: aclk
+          - const: pclk
+          - const: vclk
+          - const: lpclk
 
   resets:
-    items:
-      - description: MIPI_DSI_CMN_RSTB
-      - description: MIPI_DSI_ARESET_N
-      - description: MIPI_DSI_PRESET_N
+    oneOf:
+      - items:
+          - description: MIPI_DSI_CMN_RSTB
+          - description: MIPI_DSI_ARESET_N
+          - description: MIPI_DSI_PRESET_N
+      - items:
+          - description: MIPI_DSI_ARESET_N
+          - description: MIPI_DSI_PRESET_N
 
   reset-names:
-    items:
-      - const: rst
-      - const: arst
-      - const: prst
+    oneOf:
+      - items:
+          - const: rst
+          - const: arst
+          - const: prst
+      - items:
+          - const: arst
+          - const: prst
 
   power-domains:
     maxItems: 1
@@ -130,6 +153,41 @@ required:
 
 additionalProperties: false
 
+allOf:
+  - $ref: ../dsi-controller.yaml#
+
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: renesas,r9a09g057-mipi-dsi
+    then:
+      properties:
+        clocks:
+          maxItems: 5
+
+        clock-names:
+          maxItems: 5
+
+        resets:
+          maxItems: 2
+
+        reset-names:
+          maxItems: 2
+    else:
+      properties:
+        clocks:
+          minItems: 6
+
+        clock-names:
+          minItems: 6
+
+        resets:
+          minItems: 3
+
+        reset-names:
+          minItems: 3
+
 examples:
   - |
     #include <dt-bindings/clock/r9a07g044-cpg.h>
-- 
2.49.0


^ permalink raw reply related	[flat|nested] 18+ messages in thread

* [PATCH v5 4/4] drm: renesas: rz-du: mipi_dsi: Add support for RZ/V2H(P) SoC
  2025-05-12 18:42 [PATCH v5 0/4] Add support for DU/DSI clocks and DSI driver support for the Renesas RZ/V2H(P) SoC Prabhakar
                   ` (2 preceding siblings ...)
  2025-05-12 18:43 ` [PATCH v5 3/4] dt-bindings: display: bridge: renesas, dsi: Add support for RZ/V2H(P) SoC Prabhakar
@ 2025-05-12 18:43 ` Prabhakar
  2025-05-23 15:18   ` Geert Uytterhoeven
  3 siblings, 1 reply; 18+ messages in thread
From: Prabhakar @ 2025-05-12 18:43 UTC (permalink / raw)
  To: Andrzej Hajda, Neil Armstrong, Robert Foss, Laurent Pinchart,
	Jonas Karlman, Jernej Skrabec, David Airlie, Simona Vetter,
	Maarten Lankhorst, Maxime Ripard, Thomas Zimmermann, Rob Herring,
	Krzysztof Kozlowski, Conor Dooley, Geert Uytterhoeven,
	Michael Turquette, Stephen Boyd, Biju Das, Magnus Damm
  Cc: dri-devel, devicetree, linux-kernel, linux-renesas-soc, linux-clk,
	Prabhakar, Fabrizio Castro, Lad Prabhakar

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

Add DSI support for Renesas RZ/V2H(P) SoC.

Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
---
v4->v5:
- No changes

v3->v4
- In rzv2h_dphy_find_ulpsexit() made the array static const.

v2->v3:
- Simplifed V2H DSI timings array to save space
- Switched to use fsleep() instead of udelay()

v1->v2:
- Dropped unused macros
- Added missing LPCLK flag to rzvv2h info
---
 .../gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c    | 343 ++++++++++++++++++
 .../drm/renesas/rz-du/rzg2l_mipi_dsi_regs.h   |  34 ++
 2 files changed, 377 insertions(+)

diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
index 98d2f30ae79d..db662d6d85c8 100644
--- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
+++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
@@ -5,6 +5,7 @@
  * Copyright (C) 2022 Renesas Electronics Corporation
  */
 #include <linux/clk.h>
+#include <linux/clk/renesas-rzv2h-dsi.h>
 #include <linux/delay.h>
 #include <linux/io.h>
 #include <linux/iopoll.h>
@@ -30,6 +31,9 @@
 
 #define RZ_MIPI_DSI_FEATURE_16BPP	BIT(0)
 
+#define RZV2H_MIPI_DPHY_FOUT_MIN_IN_MEGA	(80 * MEGA)
+#define RZV2H_MIPI_DPHY_FOUT_MAX_IN_MEGA	(1500 * MEGA)
+
 struct rzg2l_mipi_dsi;
 
 struct rzg2l_mipi_dsi_hw_info {
@@ -40,6 +44,7 @@ struct rzg2l_mipi_dsi_hw_info {
 			      u64 *hsfreq_millihz);
 	unsigned int (*dphy_mode_clk_check)(struct rzg2l_mipi_dsi *dsi,
 					    unsigned long mode_freq);
+	const struct rzv2h_pll_div_limits *cpg_dsi_limits;
 	u32 phy_reg_offset;
 	u32 link_reg_offset;
 	unsigned long max_dclk;
@@ -47,6 +52,11 @@ struct rzg2l_mipi_dsi_hw_info {
 	u8 features;
 };
 
+struct rzv2h_dsi_mode_calc {
+	unsigned long mode_freq;
+	u64 mode_freq_hz;
+};
+
 struct rzg2l_mipi_dsi {
 	struct device *dev;
 	void __iomem *mmio;
@@ -68,6 +78,18 @@ struct rzg2l_mipi_dsi {
 	unsigned int num_data_lanes;
 	unsigned int lanes;
 	unsigned long mode_flags;
+
+	struct rzv2h_dsi_mode_calc mode_calc;
+	struct rzv2h_plldsi_parameters dsi_parameters;
+};
+
+static const struct rzv2h_pll_div_limits rzv2h_plldsi_div_limits = {
+	.fvco = { .min = 1050 * MEGA, .max = 2100 * MEGA },
+	.m = { .min = 64, .max = 1023 },
+	.p = { .min = 1, .max = 4 },
+	.s = { .min = 0, .max = 5 },
+	.k = { .min = -32768, .max = 32767 },
+	.csdiv = { .min = 1, .max = 1 },
 };
 
 static inline struct rzg2l_mipi_dsi *
@@ -184,6 +206,155 @@ static const struct rzg2l_mipi_dsi_timings rzg2l_mipi_dsi_global_timings[] = {
 	},
 };
 
+struct rzv2h_mipi_dsi_timings {
+	const u8 *hsfreq;
+	u8 len;
+	u8 start_index;
+};
+
+enum {
+	TCLKPRPRCTL,
+	TCLKZEROCTL,
+	TCLKPOSTCTL,
+	TCLKTRAILCTL,
+	THSPRPRCTL,
+	THSZEROCTL,
+	THSTRAILCTL,
+	TLPXCTL,
+	THSEXITCTL,
+};
+
+static const u8 tclkprprctl[] = {
+	15, 26, 37, 47, 58, 69, 79, 90, 101, 111, 122, 133, 143, 150,
+};
+
+static const u8 tclkzeroctl[] = {
+	9, 11, 13, 15, 18, 21, 23, 24, 25, 27, 29, 31, 34, 36, 38,
+	41, 43, 45, 47, 50, 52, 54, 57, 59, 61, 63, 66, 68, 70, 73,
+	75, 77, 79, 82, 84, 86, 89, 91, 93, 95, 98, 100, 102, 105,
+	107, 109, 111, 114, 116, 118, 121, 123, 125, 127, 130, 132,
+	134, 137, 139, 141, 143, 146, 148, 150,
+};
+
+static const u8 tclkpostctl[] = {
+	8, 21, 34, 48, 61, 74, 88, 101, 114, 128, 141, 150,
+};
+
+static const u8 tclktrailctl[] = {
+	14, 25, 37, 48, 59, 71, 82, 94, 105, 117, 128, 139, 150,
+};
+
+static const u8 thsprprctl[] = {
+	11, 19, 29, 40, 50, 61, 72, 82, 93, 103, 114, 125, 135, 146, 150,
+};
+
+static const u8 thszeroctl[] = {
+	18, 24, 29, 35, 40, 46, 51, 57, 62, 68, 73, 79, 84, 90,
+	95, 101, 106, 112, 117, 123, 128, 134, 139, 145, 150,
+};
+
+static const u8 thstrailctl[] = {
+	10, 21, 32, 42, 53, 64, 75, 85, 96, 107, 118, 128, 139, 150,
+};
+
+static const u8 tlpxctl[] = {
+	13, 26, 39, 53, 66, 79, 93, 106, 119, 133, 146,	150,
+};
+
+static const u8 thsexitctl[] = {
+	15, 23, 31, 39, 47, 55, 63, 71, 79, 87,
+	95, 103, 111, 119, 127, 135, 143, 150,
+};
+
+static const struct rzv2h_mipi_dsi_timings rzv2h_dsi_timings_tables[] = {
+	[TCLKPRPRCTL] = {
+		.hsfreq = tclkprprctl,
+		.len = ARRAY_SIZE(tclkprprctl),
+		.start_index = 0,
+	},
+	[TCLKZEROCTL] = {
+		.hsfreq = tclkzeroctl,
+		.len = ARRAY_SIZE(tclkzeroctl),
+		.start_index = 2,
+	},
+	[TCLKPOSTCTL] = {
+		.hsfreq = tclkpostctl,
+		.len = ARRAY_SIZE(tclkpostctl),
+		.start_index = 6,
+	},
+	[TCLKTRAILCTL] = {
+		.hsfreq = tclktrailctl,
+		.len = ARRAY_SIZE(tclktrailctl),
+		.start_index = 1,
+	},
+	[THSPRPRCTL] = {
+		.hsfreq = thsprprctl,
+		.len = ARRAY_SIZE(thsprprctl),
+		.start_index = 0,
+	},
+	[THSZEROCTL] = {
+		.hsfreq = thszeroctl,
+		.len = ARRAY_SIZE(thszeroctl),
+		.start_index = 0,
+	},
+	[THSTRAILCTL] = {
+		.hsfreq = thstrailctl,
+		.len = ARRAY_SIZE(thstrailctl),
+		.start_index = 3,
+	},
+	[TLPXCTL] = {
+		.hsfreq = tlpxctl,
+		.len = ARRAY_SIZE(tlpxctl),
+		.start_index = 0,
+	},
+	[THSEXITCTL] = {
+		.hsfreq = thsexitctl,
+		.len = ARRAY_SIZE(thsexitctl),
+		.start_index = 1,
+	},
+};
+
+static u16 rzv2h_dphy_find_ulpsexit(unsigned long freq)
+{
+	static const unsigned long hsfreq[] = {
+		1953125UL,
+		3906250UL,
+		7812500UL,
+		15625000UL,
+	};
+	static const u16 ulpsexit[] = {49, 98, 195, 391};
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(hsfreq); i++) {
+		if (freq <= hsfreq[i])
+			break;
+	}
+
+	if (i == ARRAY_SIZE(hsfreq))
+		i -= 1;
+
+	return ulpsexit[i];
+}
+
+static u16 rzv2h_dphy_find_timings_val(unsigned long freq, u8 index)
+{
+	const struct rzv2h_mipi_dsi_timings *timings;
+	u16 i;
+
+	timings = &rzv2h_dsi_timings_tables[index];
+	for (i = 0; i < timings->len; i++) {
+		unsigned long hsfreq = timings->hsfreq[i] * 10000000UL;
+
+		if (freq <= hsfreq)
+			break;
+	}
+
+	if (i == timings->len)
+		i -= 1;
+
+	return timings->start_index + i;
+};
+
 static void rzg2l_mipi_dsi_phy_write(struct rzg2l_mipi_dsi *dsi, u32 reg, u32 data)
 {
 	iowrite32(data, dsi->mmio + dsi->info->phy_reg_offset + reg);
@@ -308,6 +479,158 @@ static int rzg2l_dphy_conf_clks(struct rzg2l_mipi_dsi *dsi, unsigned long mode_f
 	return 0;
 }
 
+static unsigned int rzv2h_dphy_mode_clk_check(struct rzg2l_mipi_dsi *dsi,
+					      unsigned long mode_freq)
+{
+	struct rzv2h_plldsi_parameters *dsi_parameters = &dsi->dsi_parameters;
+	u64 hsfreq_millihz, mode_freq_hz, mode_freq_millihz;
+	struct rzv2h_plldsi_parameters cpg_dsi_parameters;
+	unsigned int bpp, i;
+
+	bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
+
+	for (i = 0; i < 10; i += 1) {
+		unsigned long hsfreq;
+		bool parameters_found;
+
+		mode_freq_hz = mode_freq * MILLI + i;
+		mode_freq_millihz = mode_freq_hz * MILLI * 1ULL;
+		parameters_found = rzv2h_dsi_get_pll_parameters_values(dsi->info->cpg_dsi_limits,
+								       &cpg_dsi_parameters,
+								       mode_freq_millihz);
+		if (!parameters_found)
+			continue;
+
+		hsfreq_millihz = DIV_ROUND_CLOSEST_ULL(cpg_dsi_parameters.freq_millihz * bpp,
+						       dsi->lanes);
+		parameters_found = rzv2h_dsi_get_pll_parameters_values(&rzv2h_plldsi_div_limits,
+								       dsi_parameters,
+								       hsfreq_millihz);
+		if (!parameters_found)
+			continue;
+
+		if (abs(dsi_parameters->error_millihz) >= 500)
+			continue;
+
+		hsfreq = DIV_ROUND_CLOSEST_ULL(hsfreq_millihz, MILLI);
+		if (hsfreq >= RZV2H_MIPI_DPHY_FOUT_MIN_IN_MEGA &&
+		    hsfreq <= RZV2H_MIPI_DPHY_FOUT_MAX_IN_MEGA) {
+			dsi->mode_calc.mode_freq_hz = mode_freq_hz;
+			dsi->mode_calc.mode_freq = mode_freq;
+			return MODE_OK;
+		}
+	}
+
+	return MODE_CLOCK_RANGE;
+}
+
+static int rzv2h_dphy_conf_clks(struct rzg2l_mipi_dsi *dsi, unsigned long mode_freq,
+				u64 *hsfreq_millihz)
+{
+	struct rzv2h_plldsi_parameters *dsi_parameters = &dsi->dsi_parameters;
+	unsigned long status;
+
+	if (dsi->mode_calc.mode_freq != mode_freq) {
+		status = rzv2h_dphy_mode_clk_check(dsi, mode_freq);
+		if (status != MODE_OK) {
+			dev_err(dsi->dev, "No PLL parameters found for mode clk %lu\n",
+				mode_freq);
+			return -EINVAL;
+		}
+	}
+
+	clk_set_rate(dsi->vclk, dsi->mode_calc.mode_freq_hz);
+	*hsfreq_millihz = dsi_parameters->freq_millihz;
+
+	return 0;
+}
+
+static int rzv2h_mipi_dsi_dphy_init(struct rzg2l_mipi_dsi *dsi,
+				    u64 hsfreq_millihz)
+{
+	struct rzv2h_plldsi_parameters *dsi_parameters = &dsi->dsi_parameters;
+	unsigned long lpclk_rate = clk_get_rate(dsi->lpclk);
+	u32 phytclksetr, phythssetr, phytlpxsetr, phycr;
+	struct rzg2l_mipi_dsi_timings dphy_timings;
+	u16 ulpsexit;
+	u64 hsfreq;
+
+	hsfreq = DIV_ROUND_CLOSEST_ULL(hsfreq_millihz, MILLI);
+
+	if (dsi_parameters->freq_millihz == hsfreq_millihz)
+		goto parameters_found;
+
+	if (rzv2h_dsi_get_pll_parameters_values(&rzv2h_plldsi_div_limits,
+						dsi_parameters, hsfreq_millihz))
+		goto parameters_found;
+
+	dev_err(dsi->dev, "No PLL parameters found for HSFREQ %lluHz\n", hsfreq);
+	return -EINVAL;
+
+parameters_found:
+	dphy_timings.tclk_trail =
+		rzv2h_dphy_find_timings_val(hsfreq, TCLKTRAILCTL);
+	dphy_timings.tclk_post =
+		rzv2h_dphy_find_timings_val(hsfreq, TCLKPOSTCTL);
+	dphy_timings.tclk_zero =
+		rzv2h_dphy_find_timings_val(hsfreq, TCLKZEROCTL);
+	dphy_timings.tclk_prepare =
+		rzv2h_dphy_find_timings_val(hsfreq, TCLKPRPRCTL);
+	dphy_timings.ths_exit =
+		rzv2h_dphy_find_timings_val(hsfreq, THSEXITCTL);
+	dphy_timings.ths_trail =
+		rzv2h_dphy_find_timings_val(hsfreq, THSTRAILCTL);
+	dphy_timings.ths_zero =
+		rzv2h_dphy_find_timings_val(hsfreq, THSZEROCTL);
+	dphy_timings.ths_prepare =
+		rzv2h_dphy_find_timings_val(hsfreq, THSPRPRCTL);
+	dphy_timings.tlpx =
+		rzv2h_dphy_find_timings_val(hsfreq, TLPXCTL);
+	ulpsexit = rzv2h_dphy_find_ulpsexit(lpclk_rate);
+
+	phytclksetr = PHYTCLKSETR_TCLKTRAILCTL(dphy_timings.tclk_trail) |
+		      PHYTCLKSETR_TCLKPOSTCTL(dphy_timings.tclk_post) |
+		      PHYTCLKSETR_TCLKZEROCTL(dphy_timings.tclk_zero) |
+		      PHYTCLKSETR_TCLKPRPRCTL(dphy_timings.tclk_prepare);
+	phythssetr = PHYTHSSETR_THSEXITCTL(dphy_timings.ths_exit) |
+		     PHYTHSSETR_THSTRAILCTL(dphy_timings.ths_trail) |
+		     PHYTHSSETR_THSZEROCTL(dphy_timings.ths_zero) |
+		     PHYTHSSETR_THSPRPRCTL(dphy_timings.ths_prepare);
+	phytlpxsetr = rzg2l_mipi_dsi_phy_read(dsi, PHYTLPXSETR) & ~GENMASK(7, 0);
+	phytlpxsetr |= PHYTLPXSETR_TLPXCTL(dphy_timings.tlpx);
+	phycr = rzg2l_mipi_dsi_phy_read(dsi, PHYCR) & ~GENMASK(9, 0);
+	phycr |= PHYCR_ULPSEXIT(ulpsexit);
+
+	/* Setting all D-PHY Timings Registers */
+	rzg2l_mipi_dsi_phy_write(dsi, PHYTCLKSETR, phytclksetr);
+	rzg2l_mipi_dsi_phy_write(dsi, PHYTHSSETR, phythssetr);
+	rzg2l_mipi_dsi_phy_write(dsi, PHYTLPXSETR, phytlpxsetr);
+	rzg2l_mipi_dsi_phy_write(dsi, PHYCR, phycr);
+
+	rzg2l_mipi_dsi_phy_write(dsi, PLLCLKSET0R,
+				 PLLCLKSET0R_PLL_S(dsi_parameters->s) |
+				 PLLCLKSET0R_PLL_P(dsi_parameters->p) |
+				 PLLCLKSET0R_PLL_M(dsi_parameters->m));
+	rzg2l_mipi_dsi_phy_write(dsi, PLLCLKSET1R, PLLCLKSET1R_PLL_K(dsi_parameters->k));
+	fsleep(20);
+
+	rzg2l_mipi_dsi_phy_write(dsi, PLLENR, PLLENR_PLLEN);
+	fsleep(500);
+
+	return 0;
+}
+
+static void rzv2h_mipi_dsi_dphy_late_init(struct rzg2l_mipi_dsi *dsi)
+{
+	fsleep(220);
+	rzg2l_mipi_dsi_phy_write(dsi, PHYRSTR, PHYRSTR_PHYMRSTN);
+}
+
+static void rzv2h_mipi_dsi_dphy_exit(struct rzg2l_mipi_dsi *dsi)
+{
+	rzg2l_mipi_dsi_phy_write(dsi, PLLENR, 0);
+}
+
 static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
 				  const struct drm_display_mode *mode)
 {
@@ -410,6 +733,9 @@ static void rzg2l_mipi_dsi_set_display_timing(struct rzg2l_mipi_dsi *dsi,
 	case 18:
 		vich1ppsetr = VICH1PPSETR_DT_RGB18;
 		break;
+	case 16:
+		vich1ppsetr = VICH1PPSETR_DT_RGB16;
+		break;
 	}
 
 	if ((dsi->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE) &&
@@ -861,6 +1187,22 @@ static void rzg2l_mipi_dsi_remove(struct platform_device *pdev)
 	pm_runtime_disable(&pdev->dev);
 }
 
+RZV2H_CPG_PLL_DSI_LIMITS(rzv2h_cpg_pll_dsi_limits);
+
+static const struct rzg2l_mipi_dsi_hw_info rzv2h_mipi_dsi_info = {
+	.dphy_init = rzv2h_mipi_dsi_dphy_init,
+	.dphy_late_init = rzv2h_mipi_dsi_dphy_late_init,
+	.dphy_exit = rzv2h_mipi_dsi_dphy_exit,
+	.dphy_mode_clk_check = rzv2h_dphy_mode_clk_check,
+	.dphy_conf_clks = rzv2h_dphy_conf_clks,
+	.cpg_dsi_limits = &rzv2h_cpg_pll_dsi_limits,
+	.phy_reg_offset = 0x10000,
+	.link_reg_offset = 0,
+	.max_dclk = 187500,
+	.min_dclk = 5440,
+	.features = RZ_MIPI_DSI_FEATURE_16BPP,
+};
+
 static const struct rzg2l_mipi_dsi_hw_info rzg2l_mipi_dsi_info = {
 	.dphy_init = rzg2l_mipi_dsi_dphy_init,
 	.dphy_exit = rzg2l_mipi_dsi_dphy_exit,
@@ -871,6 +1213,7 @@ static const struct rzg2l_mipi_dsi_hw_info rzg2l_mipi_dsi_info = {
 };
 
 static const struct of_device_id rzg2l_mipi_dsi_of_table[] = {
+	{ .compatible = "renesas,r9a09g057-mipi-dsi", .data = &rzv2h_mipi_dsi_info, },
 	{ .compatible = "renesas,rzg2l-mipi-dsi", .data = &rzg2l_mipi_dsi_info, },
 	{ /* sentinel */ }
 };
diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi_regs.h b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi_regs.h
index 16efe4dc59f4..68165395d61c 100644
--- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi_regs.h
+++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi_regs.h
@@ -40,6 +40,39 @@
 #define DSIDPHYTIM3_THS_TRAIL(x)	((x) << 8)
 #define DSIDPHYTIM3_THS_ZERO(x)		((x) << 0)
 
+/* RZ/V2H DPHY Registers */
+#define PLLENR				0x000
+#define PLLENR_PLLEN			BIT(0)
+
+#define PHYRSTR				0x004
+#define PHYRSTR_PHYMRSTN		BIT(0)
+
+#define PLLCLKSET0R			0x010
+#define PLLCLKSET0R_PLL_S(x)		((x) << 0)
+#define PLLCLKSET0R_PLL_P(x)		((x) << 8)
+#define PLLCLKSET0R_PLL_M(x)		((x) << 16)
+
+#define PLLCLKSET1R			0x014
+#define PLLCLKSET1R_PLL_K(x)		((x) << 0)
+
+#define PHYTCLKSETR			0x020
+#define PHYTCLKSETR_TCLKTRAILCTL(x)	((x) << 0)
+#define PHYTCLKSETR_TCLKPOSTCTL(x)	((x) << 8)
+#define PHYTCLKSETR_TCLKZEROCTL(x)	((x) << 16)
+#define PHYTCLKSETR_TCLKPRPRCTL(x)	((x) << 24)
+
+#define PHYTHSSETR			0x024
+#define PHYTHSSETR_THSEXITCTL(x)	((x) << 0)
+#define PHYTHSSETR_THSTRAILCTL(x)	((x) << 8)
+#define PHYTHSSETR_THSZEROCTL(x)	((x) << 16)
+#define PHYTHSSETR_THSPRPRCTL(x)	((x) << 24)
+
+#define PHYTLPXSETR			0x028
+#define PHYTLPXSETR_TLPXCTL(x)		((x) << 0)
+
+#define PHYCR				0x030
+#define PHYCR_ULPSEXIT(x)		((x) << 0)
+
 /* --------------------------------------------------------*/
 
 /* Link Status Register */
@@ -116,6 +149,7 @@
 
 /* Video-Input Channel 1 Pixel Packet Set Register */
 #define VICH1PPSETR			0x420
+#define VICH1PPSETR_DT_RGB16		(0x0e << 16)
 #define VICH1PPSETR_DT_RGB18		(0x1e << 16)
 #define VICH1PPSETR_DT_RGB18_LS		(0x2e << 16)
 #define VICH1PPSETR_DT_RGB24		(0x3e << 16)
-- 
2.49.0


^ permalink raw reply related	[flat|nested] 18+ messages in thread

* RE: [PATCH v5 1/4] clk: renesas: rzv2h-cpg: Add support for DSI clocks
  2025-05-12 18:42 ` [PATCH v5 1/4] clk: renesas: rzv2h-cpg: Add support for DSI clocks Prabhakar
@ 2025-05-20  6:19   ` Biju Das
  2025-05-23 14:45   ` Geert Uytterhoeven
  1 sibling, 0 replies; 18+ messages in thread
From: Biju Das @ 2025-05-20  6:19 UTC (permalink / raw)
  To: Prabhakar, Andrzej Hajda, Neil Armstrong, Robert Foss,
	laurent.pinchart, Jonas Karlman, Jernej Skrabec, David Airlie,
	Simona Vetter, Maarten Lankhorst, Maxime Ripard,
	Thomas Zimmermann, Rob Herring, Krzysztof Kozlowski, Conor Dooley,
	Geert Uytterhoeven, Michael Turquette, Stephen Boyd, Magnus Damm
  Cc: dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org,
	linux-kernel@vger.kernel.org, linux-renesas-soc@vger.kernel.org,
	linux-clk@vger.kernel.org, Fabrizio Castro, Prabhakar Mahadev Lad

Hi Geert, Stephen,

> -----Original Message-----
> From: Prabhakar <prabhakar.csengg@gmail.com>
> Sent: 12 May 2025 19:43
> Subject: [PATCH v5 1/4] clk: renesas: rzv2h-cpg: Add support for DSI clocks
> 
> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> 
> Add support for PLLDSI and PLLDSI divider clocks.
> 
> Introduce the `renesas-rzv2h-dsi.h` header to centralize and share PLLDSI-related data structures,
> limits, and algorithms between the RZ/V2H 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@renesas.com>
> Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> ---
> 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       | 237 +++++++++++++++++++++++++-
>  drivers/clk/renesas/rzv2h-cpg.h       |  14 ++
>  include/linux/clk/renesas-rzv2h-dsi.h | 211 +++++++++++++++++++++++
>  3 files changed, 460 insertions(+), 2 deletions(-)  create mode 100644 include/linux/clk/renesas-
> rzv2h-dsi.h
> 
> diff --git a/drivers/clk/renesas/rzv2h-cpg.c b/drivers/clk/renesas/rzv2h-cpg.c index
> 882e301c2d1b..ccf6a664e71d 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-dsi.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>
> 
> @@ -48,6 +53,7 @@
>  #define CPG_PLL_STBY(x)		((x))
>  #define CPG_PLL_STBY_RESETB	BIT(0)
>  #define CPG_PLL_STBY_RESETB_WEN	BIT(16)
> +#define CPG_PLL_STBY_SSCGEN_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))
> @@ -79,6 +85,8 @@
>   * @last_dt_core_clk: ID of the last Core Clock exported to DT
>   * @mstop_count: Array of mstop values
>   * @rcdev: Reset controller entity
> + * @dsi_limits: PLL DSI parameters limits
> + * @plldsi_div_parameters: PLL DSI and divider parameters configuration
>   */
>  struct rzv2h_cpg_priv {
>  	struct device *dev;
> @@ -95,6 +103,9 @@ struct rzv2h_cpg_priv {
>  	atomic_t *mstop_count;
> 
>  	struct reset_controller_dev rcdev;
> +
> +	const struct rzv2h_pll_div_limits *dsi_limits;
> +	struct rzv2h_plldsi_parameters plldsi_div_parameters;
>  };
> 
>  #define rcdev_to_priv(x)	container_of(x, struct rzv2h_cpg_priv, rcdev)
> @@ -150,6 +161,24 @@ struct ddiv_clk {
> 
>  #define to_ddiv_clock(_div) container_of(_div, struct ddiv_clk, div)
> 
> +/**
> + * 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 int rzv2h_cpg_pll_clk_is_enabled(struct clk_hw *hw)  {
>  	struct pll_clk *pll_clk = to_pll(hw);
> @@ -198,6 +227,188 @@ static int rzv2h_cpg_pll_clk_enable(struct clk_hw *hw)
>  	return ret;
>  }
> 
> +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 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_plldsi_parameters *dsi_dividers = &priv->plldsi_div_parameters;
> +	u64 rate_millihz;
> +
> +	/*
> +	 * Adjust the requested clock rate (`req->rate`) to ensure it falls within
> +	 * the supported range of 5.44 MHz to 187.5 MHz.
> +	 */
> +	req->rate = clamp(req->rate, 5440000UL, 187500000UL);
> +
> +	rate_millihz = mul_u32_u32(req->rate, MILLI);
> +	if (rate_millihz == dsi_dividers->error_millihz + dsi_dividers->freq_millihz)
> +		goto exit_determine_rate;
> +
> +	if (!rzv2h_dsi_get_pll_parameters_values(priv->dsi_limits,
> +						 dsi_dividers, rate_millihz)) {
> +		dev_err(priv->dev,
> +			"failed to determine rate for req->rate: %lu\n",
> +			req->rate);
> +		return -EINVAL;
> +	}
> +
> +exit_determine_rate:
> +	req->best_parent_rate = req->rate * dsi_dividers->csdiv;
> +
> +	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_plldsi_parameters *dsi_dividers = &priv->plldsi_div_parameters;
> +	struct ddiv ddiv = dsi_div->ddiv;
> +	const struct clk_div_table *clkt;
> +	bool div_found = false;
> +	u32 val, shift, div;
> +
> +	div = dsi_dividers->csdiv;
> +	for (clkt = dsi_div->dtable; clkt->div; clkt++) {
> +		if (clkt->div == div) {
> +			div_found = true;
> +			break;
> +		}
> +	}
> +
> +	if (!div_found)
> +		return -EINVAL;
> +
> +	shift = ddiv.shift;
> +	val = readl(priv->base + ddiv.offset) | DDIV_DIVCTL_WEN(shift);
> +	val &= ~(clk_div_mask(ddiv.width) << shift);
> +	val |= (u32)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 long rzv2h_cpg_plldsi_round_rate(struct clk_hw *hw,
> +					unsigned long rate,
> +					unsigned long *parent_rate)
> +{
> +	return clamp(rate, 25000000UL, 375000000UL); }
> +
> +static int rzv2h_cpg_pll_set_rate(struct clk_hw *hw,
> +				  unsigned long rate,
> +				  unsigned long parent_rate)
> +{
> +	struct pll_clk *pll_clk = to_pll(hw);
> +	struct rzv2h_cpg_priv *priv = pll_clk->priv;
> +	struct rzv2h_plldsi_parameters *dsi_dividers;
> +	struct pll pll = pll_clk->pll;
> +	u16 offset = 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;
> +	}
> +
> +	dsi_dividers = &priv->plldsi_div_parameters;
> +	/* Output clock setting 1 */
> +	writel((dsi_dividers->k << 16) | (dsi_dividers->m << 6) | (dsi_dividers->p),
> +	       priv->base + CPG_PLL_CLK1(offset));
> +
> +	/* Output clock setting 2 */
> +	val = readl(priv->base + CPG_PLL_CLK2(offset));
> +	writel((val & ~GENMASK(2, 0)) | dsi_dividers->s,
> +	       priv->base + CPG_PLL_CLK2(offset));
> +
> +	/* Put PLL to normal mode */
> +	writel(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 unsigned long rzv2h_cpg_pll_clk_recalc_rate(struct clk_hw *hw,
>  						   unsigned long parent_rate)
>  {
> @@ -219,6 +430,12 @@ static unsigned long rzv2h_cpg_pll_clk_recalc_rate(struct clk_hw *hw,
>  	return DIV_ROUND_CLOSEST_ULL(rate, CPG_PLL_CLK1_PDIV(clk1));  }
> 
> +static const struct clk_ops rzv2h_cpg_plldsi_ops = {
> +	.recalc_rate = rzv2h_cpg_pll_clk_recalc_rate,
> +	.round_rate = rzv2h_cpg_plldsi_round_rate,
> +	.set_rate = rzv2h_cpg_pll_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,
> @@ -228,7 +445,8 @@ 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 turn_on)
>  {
>  	void __iomem *base = priv->base;
>  	struct device *dev = priv->dev;
> @@ -258,6 +476,13 @@ rzv2h_cpg_pll_clk_register(const struct cpg_core_clk *core,
>  	pll_clk->base = base;
>  	pll_clk->priv = priv;
> 
> +	if (turn_on) {
> +		/* Disable SSC and turn on PLL clock when init */
> +		writel(CPG_PLL_STBY_RESETB_WEN | CPG_PLL_STBY_RESETB |
> +		       CPG_PLL_STBY_SSCGEN_WEN,
> +		       base + CPG_PLL_STBY(pll_clk->pll.offset));
> +	}
> +
>  	ret = devm_clk_hw_register(dev, &pll_clk->hw);
>  	if (ret)
>  		return ERR_PTR(ret);
> @@ -499,7 +724,7 @@ rzv2h_cpg_register_core_clk(const struct cpg_core_clk *core,
>  			clk = clk_hw->clk;
>  		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); @@ -507,6 +732,12 @@
> 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;
>  	}
> @@ -1043,6 +1274,8 @@ static int __init rzv2h_cpg_probe(struct platform_device *pdev)
>  	priv->last_dt_core_clk = info->last_dt_core_clk;
>  	priv->num_resets = info->num_resets;
> 
> +	priv->dsi_limits = info->plldsi_limits;
> +
>  	for (i = 0; i < nclks; i++)
>  		clks[i] = ERR_PTR(-ENOENT);
> 
> diff --git a/drivers/clk/renesas/rzv2h-cpg.h b/drivers/clk/renesas/rzv2h-cpg.h index
> cd6bcd4f2901..6f662fa86ac4 100644
> --- a/drivers/clk/renesas/rzv2h-cpg.h
> +++ b/drivers/clk/renesas/rzv2h-cpg.h
> @@ -100,6 +100,7 @@ struct smuxed {
>  #define CPG_CDDIV3		(0x40C)
>  #define CPG_CDDIV4		(0x410)
>  #define CPG_CSDIV0		(0x500)
> +#define CPG_CSDIV1		(0x504)
> 
>  #define CDDIV0_DIVCTL1	DDIV_PACK(CPG_CDDIV0, 4, 3, 1)
>  #define CDDIV0_DIVCTL2	DDIV_PACK(CPG_CDDIV0, 8, 3, 2)
> @@ -168,6 +169,8 @@ 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...) \ @@ -195,6 +198,14 @@ 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 @@ -295,6 +306,7 @@ struct rzv2h_reset {
>   *
>   * @num_mstop_bits: Maximum number of MSTOP bits supported, equivalent to the
>   *		    number of CPG_BUS_m_MSTOP registers multiplied by 16.
> + * @plldsi_limits: PLL DSI parameters limits
>   */
>  struct rzv2h_cpg_info {
>  	/* Core Clocks */
> @@ -313,6 +325,8 @@ struct rzv2h_cpg_info {
>  	unsigned int num_resets;
> 
>  	unsigned int num_mstop_bits;
> +
> +	const struct rzv2h_pll_div_limits *plldsi_limits;
>  };
> 
>  extern const struct rzv2h_cpg_info r9a09g047_cpg_info; diff --git a/include/linux/clk/renesas-rzv2h-
> dsi.h b/include/linux/clk/renesas-rzv2h-dsi.h
> new file mode 100644
> index 000000000000..faecb5d49c20
> --- /dev/null
> +++ b/include/linux/clk/renesas-rzv2h-dsi.h
> @@ -0,0 +1,211 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Renesas RZ/V2H(P) DSI CPG helper
> + *
> + * Copyright (C) 2025 Renesas Electronics Corp.
> + */
> +#ifndef __RENESAS_RZV2H_DSI_H__
> +#define __RENESAS_RZV2H_DSI_H__
> +
> +#include <linux/limits.h>
> +#include <linux/math.h>
> +#include <linux/math64.h>
> +#include <linux/units.h>
> +
> +#define OSC_CLK_IN_MEGA		(24 * MEGA)
> +
> +struct rzv2h_pll_div_limits {
> +	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 {
> +		u8 min;
> +		u8 max;
> +	} csdiv;
> +};
> +
> +struct rzv2h_plldsi_parameters {
> +	u64 freq_millihz;
> +	s64 error_millihz;
> +	u16 m;
> +	s16 k;
> +	u8 csdiv;
> +	u8 p;
> +	u8 s;
> +};
> +
> +#define RZV2H_CPG_PLL_DSI_LIMITS(name)					\
> +	static const struct rzv2h_pll_div_limits (name) = {		\
> +		.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 },			\
> +		.csdiv = { .min = 2, .max = 32 },			\
> +	}								\
> +
> +/**
> + * rzv2h_dsi_get_pll_parameters_values - 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 and
> + * divider values
> + * @pars: Pointer to the structure where the best calculated PLL
> +parameters and divider
> + * values will be stored
> + * @freq_millihz: Target output frequency in millihertz
> + *
> + * This function calculates the best set of PLL parameters (M, K, P, S)
> +and divider
> + * value (CSDIV) to achieve the desired frequency.
> + * There is no direct formula to calculate the PLL parameters and the
> +divider value,
> + * 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 divider values is found, false otherwise.
> + */
> +static __maybe_unused bool
> +rzv2h_dsi_get_pll_parameters_values(const struct rzv2h_pll_div_limits *limits,
> +				    struct rzv2h_plldsi_parameters *pars,
> +				    u64 freq_millihz)
> +{
> +	struct rzv2h_plldsi_parameters p, best;
> +
> +	/* Initialize best error to maximum possible value */
> +	best.error_millihz = S64_MAX;
> +
> +	for (p.csdiv = limits->csdiv.min; p.csdiv <= limits->csdiv.max; p.csdiv += 2) {
> +		for (p.p = limits->p.min; p.p <= limits->p.max; p.p++) {
> +			u32 fref = OSC_CLK_IN_MEGA / p.p;
> +
> +			for (p.s = limits->s.min; p.s <= limits->s.max; p.s++) {
> +				u16 two_pow_s = 1 << p.s;
> +				u16 divider = two_pow_s * p.csdiv;
> +
> +				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 combination of the
> +					 * PLL + divider is calculated as follows:
> +					 *
> +					 * Freq = Ffout / csdiv
> +					 *
> +					 * With:
> +					 * 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) * csdiv))
> +					 *      = Ffvco / divider
> +					 *      = (pll_m * Ffref) / divider + ((pll_k / 65536) * Ffref) /
> divider
> +					 *      = output_m + output_k
> +					 *
> +					 * Every parameter has been determined at this point, but pll_k.
> +					 * Considering that:
> +					 * -32768 <= pll_k <= 32767
> +					 * Then:
> +					 * -0.5 <= (pll_k / 65536) < 0.5
> +					 * Therefore:
> +					 * -Ffref / (2 * divider) <= output_k < Ffref / (2 * divider)
> +					 */
> +
> +					/* Compute output M component (in mHz) */
> +					output_m = DIV_ROUND_CLOSEST_ULL(p.m * fref * 1000ULL,
> +									 divider);
> +					/* Compute range for output K (in mHz) */
> +					output_k_range = DIV_ROUND_CLOSEST_ULL(fref * 1000ULL,
> +									       divider * 2);
> +					/*
> +					 * 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) / divider
> +					 * Therefore:
> +					 * pll_k = (output_k * 65536 * divider) / Ffref
> +					 */
> +					output_k = freq_millihz - output_m;
> +					pll_k = div64_s64(output_k * 65536ULL * divider, fref);
> +					pll_k = DIV_S64_ROUND_CLOSEST(pll_k, 1000);
> +
> +					/* 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 = ((p.m * 65536ULL) + p.k) * fref;
> +					if ((fvco < (limits->fvco.min * 65536ULL)) ||
> +					    (fvco > (limits->fvco.max * 65536ULL)))
> +						continue;
> +
> +					/* PLL_M component of (output * 65536 * PLL_P) */
> +					output = p.m * 65536ULL * OSC_CLK_IN_MEGA;
> +					/* PLL_K component of (output * 65536 * PLL_P) */
> +					output += p.k * OSC_CLK_IN_MEGA;
> +					/* Make it in mHz */
> +					output *= 1000ULL;
> +					output /= 65536ULL * p.p * divider;
> +
> +					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;
> +}

Are you ok with this approach? or some other generic method in clock Framework to handle the milli Hertz ??

for eg: Maybe like introducing get and set to retrieve
the fractional part in clock Framework to handle the milli Hertz?

Cheers,
Biju

> +
> +#endif	/* __RENESAS_RZV2H_DSI_H__ */
> --
> 2.49.0


^ permalink raw reply	[flat|nested] 18+ messages in thread

* Re: [PATCH v5 1/4] clk: renesas: rzv2h-cpg: Add support for DSI clocks
  2025-05-12 18:42 ` [PATCH v5 1/4] clk: renesas: rzv2h-cpg: Add support for DSI clocks Prabhakar
  2025-05-20  6:19   ` Biju Das
@ 2025-05-23 14:45   ` Geert Uytterhoeven
  2025-05-27 21:50     ` Lad, Prabhakar
  1 sibling, 1 reply; 18+ messages in thread
From: Geert Uytterhoeven @ 2025-05-23 14:45 UTC (permalink / raw)
  To: Prabhakar, Fabrizio Castro
  Cc: Andrzej Hajda, Neil Armstrong, Robert Foss, Laurent Pinchart,
	Jonas Karlman, Jernej Skrabec, David Airlie, Simona Vetter,
	Maarten Lankhorst, Maxime Ripard, Thomas Zimmermann, Rob Herring,
	Krzysztof Kozlowski, Conor Dooley, Michael Turquette,
	Stephen Boyd, Biju Das, Magnus Damm, dri-devel, devicetree,
	linux-kernel, linux-renesas-soc, linux-clk, Lad Prabhakar

Hi Prabhakar, Fabrizio,

On Mon, 12 May 2025 at 20:43, Prabhakar <prabhakar.csengg@gmail.com> wrote:
> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
>
> Add support for PLLDSI and PLLDSI divider clocks.
>
> Introduce the `renesas-rzv2h-dsi.h` header to centralize and share
> PLLDSI-related data structures, limits, and algorithms between the RZ/V2H
> 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@renesas.com>
> Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

Thanks for your patch!

> --- a/drivers/clk/renesas/rzv2h-cpg.c
> +++ b/drivers/clk/renesas/rzv2h-cpg.c
> @@ -48,6 +53,7 @@
>  #define CPG_PLL_STBY(x)                ((x))
>  #define CPG_PLL_STBY_RESETB    BIT(0)
>  #define CPG_PLL_STBY_RESETB_WEN        BIT(16)
> +#define CPG_PLL_STBY_SSCGEN_WEN BIT(18)

CPG_PLL_STBY_SSC_EN_WEN?

>  #define CPG_PLL_CLK1(x)                ((x) + 0x004)
>  #define CPG_PLL_CLK1_KDIV(x)   ((s16)FIELD_GET(GENMASK(31, 16), (x)))

You are already using FIELD_GET() for extracting the K, M, P, and
S fields, but are still still open-coding shifts for writing in
rzv2h_cpg_pll_set_rate().

What about replacing CPG_PLL_CLK1_KDIV() by:

    #define CPG_PLL_CLK1_DIV_K    GENMASK(31,16)

Then the code can use:

    (s16)FIELD_GET(CPG_PLL_CLK1_DIV_K, clk1)

for reading and:

    FIELD_PREP(CPG_PLL_CLK1_DIV_K, (u16)k) | ...

for writing?

Same for the M, P, and S fields (but without the s16/u16 casts, as
they are unsigned, unlike K).

>  #define CPG_PLL_CLK1_MDIV(x)   FIELD_GET(GENMASK(15, 6), (x))

> @@ -198,6 +227,188 @@ static int rzv2h_cpg_pll_clk_enable(struct clk_hw *hw)
>         return ret;
>  }
>
> +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 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_plldsi_parameters *dsi_dividers = &priv->plldsi_div_parameters;
> +       u64 rate_millihz;
> +
> +       /*
> +        * Adjust the requested clock rate (`req->rate`) to ensure it falls within
> +        * the supported range of 5.44 MHz to 187.5 MHz.
> +        */
> +       req->rate = clamp(req->rate, 5440000UL, 187500000UL);
> +
> +       rate_millihz = mul_u32_u32(req->rate, MILLI);
> +       if (rate_millihz == dsi_dividers->error_millihz + dsi_dividers->freq_millihz)
> +               goto exit_determine_rate;
> +
> +       if (!rzv2h_dsi_get_pll_parameters_values(priv->dsi_limits,
> +                                                dsi_dividers, rate_millihz)) {
> +               dev_err(priv->dev,
> +                       "failed to determine rate for req->rate: %lu\n",
> +                       req->rate);
> +               return -EINVAL;
> +       }
> +
> +exit_determine_rate:
> +       req->best_parent_rate = req->rate * dsi_dividers->csdiv;

Shouldn't this also update req->rate with the actual rate?

    req->rate = DIV_ROUND_CLOSEST_ULL(dsi_dividers->freq_millihz, MILLI);

Would it help the DSI driver if this clock would provide a
.recalc_accuracy() callback that takes into account the difference
between req->rate and dsi_dividers->freq_millihz?
Or would that be considered abuse of the accuracy concept?

> +
> +       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_plldsi_parameters *dsi_dividers = &priv->plldsi_div_parameters;
> +       struct ddiv ddiv = dsi_div->ddiv;
> +       const struct clk_div_table *clkt;
> +       bool div_found = false;
> +       u32 val, shift, div;
> +
> +       div = dsi_dividers->csdiv;
> +       for (clkt = dsi_div->dtable; clkt->div; clkt++) {
> +               if (clkt->div == div) {
> +                       div_found = true;
> +                       break;
> +               }
> +       }
> +
> +       if (!div_found)
> +               return -EINVAL;
> +
> +       shift = ddiv.shift;
> +       val = readl(priv->base + ddiv.offset) | DDIV_DIVCTL_WEN(shift);
> +       val &= ~(clk_div_mask(ddiv.width) << shift);
> +       val |= (u32)clkt->val << shift;

No need for the cast.

> +       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 long rzv2h_cpg_plldsi_round_rate(struct clk_hw *hw,
> +                                       unsigned long rate,
> +                                       unsigned long *parent_rate)
> +{
> +       return clamp(rate, 25000000UL, 375000000UL);

This only brings the desired rate into the supported range, but does
not round it to the nearest rate that is actually supported.

> +}
> +
> +static int rzv2h_cpg_pll_set_rate(struct clk_hw *hw,
> +                                 unsigned long rate,
> +                                 unsigned long parent_rate)
> +{
> +       struct pll_clk *pll_clk = to_pll(hw);
> +       struct rzv2h_cpg_priv *priv = pll_clk->priv;
> +       struct rzv2h_plldsi_parameters *dsi_dividers;
> +       struct pll pll = pll_clk->pll;
> +       u16 offset = 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;
> +       }
> +
> +       dsi_dividers = &priv->plldsi_div_parameters;
> +       /* Output clock setting 1 */
> +       writel((dsi_dividers->k << 16) | (dsi_dividers->m << 6) | (dsi_dividers->p),

This is where you want to use FIELD_PREP().

> +              priv->base + CPG_PLL_CLK1(offset));
> +
> +       /* Output clock setting 2 */
> +       val = readl(priv->base + CPG_PLL_CLK2(offset));
> +       writel((val & ~GENMASK(2, 0)) | dsi_dividers->s,

(val & ~CPG_PLL_CLK2_DIV_S) | FIELD_PREP(...)

> +              priv->base + CPG_PLL_CLK2(offset));
> +
> +       /* Put PLL to normal mode */
> +       writel(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 unsigned long rzv2h_cpg_pll_clk_recalc_rate(struct clk_hw *hw,
>                                                    unsigned long parent_rate)
>  {

> --- a/drivers/clk/renesas/rzv2h-cpg.h
> +++ b/drivers/clk/renesas/rzv2h-cpg.h
> @@ -100,6 +100,7 @@ struct smuxed {
>  #define CPG_CDDIV3             (0x40C)
>  #define CPG_CDDIV4             (0x410)
>  #define CPG_CSDIV0             (0x500)
> +#define CPG_CSDIV1             (0x504)

Unused until [PATCH v5 2/4], so please move it there.

>
>  #define CDDIV0_DIVCTL1 DDIV_PACK(CPG_CDDIV0, 4, 3, 1)
>  #define CDDIV0_DIVCTL2 DDIV_PACK(CPG_CDDIV0, 8, 3, 2)

> --- /dev/null
> +++ b/include/linux/clk/renesas-rzv2h-dsi.h
> @@ -0,0 +1,211 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Renesas RZ/V2H(P) DSI CPG helper
> + *
> + * Copyright (C) 2025 Renesas Electronics Corp.
> + */
> +#ifndef __RENESAS_RZV2H_DSI_H__
> +#define __RENESAS_RZV2H_DSI_H__
> +
> +#include <linux/limits.h>
> +#include <linux/math.h>
> +#include <linux/math64.h>
> +#include <linux/units.h>
> +
> +#define OSC_CLK_IN_MEGA                (24 * MEGA)
> +
> +struct rzv2h_pll_div_limits {
> +       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 {
> +               u8 min;
> +               u8 max;
> +       } csdiv;
> +};
> +
> +struct rzv2h_plldsi_parameters {
> +       u64 freq_millihz;
> +       s64 error_millihz;
> +       u16 m;
> +       s16 k;
> +       u8 csdiv;
> +       u8 p;
> +       u8 s;
> +};
> +
> +#define RZV2H_CPG_PLL_DSI_LIMITS(name)                                 \
> +       static const struct rzv2h_pll_div_limits (name) = {             \
> +               .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 },                   \
> +               .csdiv = { .min = 2, .max = 32 },                       \
> +       }                                                               \
> +
> +/**
> + * rzv2h_dsi_get_pll_parameters_values - 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 and
> + * divider values
> + * @pars: Pointer to the structure where the best calculated PLL parameters and divider
> + * values will be stored
> + * @freq_millihz: Target output frequency in millihertz
> + *
> + * This function calculates the best set of PLL parameters (M, K, P, S) and divider
> + * value (CSDIV) to achieve the desired frequency.
> + * There is no direct formula to calculate the PLL parameters and the divider value,
> + * 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 divider values is found, false otherwise.
> + */
> +static __maybe_unused bool
> +rzv2h_dsi_get_pll_parameters_values(const struct rzv2h_pll_div_limits *limits,
> +                                   struct rzv2h_plldsi_parameters *pars,
> +                                   u64 freq_millihz)
> +{
> +       struct rzv2h_plldsi_parameters p, best;
> +
> +       /* Initialize best error to maximum possible value */
> +       best.error_millihz = S64_MAX;
> +
> +       for (p.csdiv = limits->csdiv.min; p.csdiv <= limits->csdiv.max; p.csdiv += 2) {
> +               for (p.p = limits->p.min; p.p <= limits->p.max; p.p++) {
> +                       u32 fref = OSC_CLK_IN_MEGA / p.p;
> +
> +                       for (p.s = limits->s.min; p.s <= limits->s.max; p.s++) {
> +                               u16 two_pow_s = 1 << p.s;
> +                               u16 divider = two_pow_s * p.csdiv;

No need for two_pow_s.  You can initialize divider = p.csdiv << s.min
at the start of the loop, and multiply by two after each iteration.

> +
> +                               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 combination of the
> +                                        * PLL + divider is calculated as follows:
> +                                        *
> +                                        * Freq = Ffout / csdiv
> +                                        *
> +                                        * With:
> +                                        * 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) * csdiv))
> +                                        *      = Ffvco / divider
> +                                        *      = (pll_m * Ffref) / divider + ((pll_k / 65536) * Ffref) / divider
> +                                        *      = output_m + output_k
> +                                        *
> +                                        * Every parameter has been determined at this point, but pll_k.
> +                                        * Considering that:
> +                                        * -32768 <= pll_k <= 32767
> +                                        * Then:
> +                                        * -0.5 <= (pll_k / 65536) < 0.5
> +                                        * Therefore:
> +                                        * -Ffref / (2 * divider) <= output_k < Ffref / (2 * divider)
> +                                        */
> +
> +                                       /* Compute output M component (in mHz) */
> +                                       output_m = DIV_ROUND_CLOSEST_ULL(p.m * fref * 1000ULL,

"p.m * fref" may overflow => mul_u32_u32(p.m, fref) * MILLI;

> +                                                                        divider);
> +                                       /* Compute range for output K (in mHz) */
> +                                       output_k_range = DIV_ROUND_CLOSEST_ULL(fref * 1000ULL,

mul_u32_u32(fref, MILLI)

> +                                                                              divider * 2);
> +                                       /*
> +                                        * 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) / divider
> +                                        * Therefore:
> +                                        * pll_k = (output_k * 65536 * divider) / Ffref
> +                                        */
> +                                       output_k = freq_millihz - output_m;
> +                                       pll_k = div64_s64(output_k * 65536ULL * divider, fref);

div_s64(), as fref is 32-bit.

> +                                       pll_k = DIV_S64_ROUND_CLOSEST(pll_k, 1000);

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 = ((p.m * 65536ULL) + p.k) * fref;

mul_u32(p.m * 65536 + p.k, fref)

I guess the compiler is sufficiently smart to turn that into a shift.
The alternative would be to use a cast (I try to avoid them) and a shift:

mul_u32((u64)p.m << 16 + p.k, fref)

> +                                       if ((fvco < (limits->fvco.min * 65536ULL)) ||
> +                                           (fvco > (limits->fvco.max * 65536ULL)))

mul_u32_u32(..., 65536) for both

> +                                               continue;
> +
> +                                       /* PLL_M component of (output * 65536 * PLL_P) */
> +                                       output = p.m * 65536ULL * OSC_CLK_IN_MEGA;

mul_u32(p.m * 65536, OSC_CLK_IN_MEGA)

> +                                       /* PLL_K component of (output * 65536 * PLL_P) */
> +                                       output += p.k * OSC_CLK_IN_MEGA;
> +                                       /* Make it in mHz */
> +                                       output *= 1000ULL;

No need for the ULL => MILLI

> +                                       output /= 65536ULL * p.p * divider;

mul_u32()

No rounding for the division?

> +
> +                                       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;
> +}
> +
> +#endif /* __RENESAS_RZV2H_DSI_H__ */

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

^ permalink raw reply	[flat|nested] 18+ messages in thread

* Re: [PATCH v5 2/4] clk: renesas: r9a09g057: Add clock and reset entries for DSI and LCDC
  2025-05-12 18:43 ` [PATCH v5 2/4] clk: renesas: r9a09g057: Add clock and reset entries for DSI and LCDC Prabhakar
@ 2025-05-23 14:46   ` Geert Uytterhoeven
  2025-05-27 22:01     ` Lad, Prabhakar
  0 siblings, 1 reply; 18+ messages in thread
From: Geert Uytterhoeven @ 2025-05-23 14:46 UTC (permalink / raw)
  To: Prabhakar, Fabrizio Castro
  Cc: Andrzej Hajda, Neil Armstrong, Robert Foss, Laurent Pinchart,
	Jonas Karlman, Jernej Skrabec, David Airlie, Simona Vetter,
	Maarten Lankhorst, Maxime Ripard, Thomas Zimmermann, Rob Herring,
	Krzysztof Kozlowski, Conor Dooley, Michael Turquette,
	Stephen Boyd, Biju Das, Magnus Damm, dri-devel, devicetree,
	linux-kernel, linux-renesas-soc, linux-clk, Lad Prabhakar

Hi Prabhakar, Fabrizio,

On Mon, 12 May 2025 at 20:43, Prabhakar <prabhakar.csengg@gmail.com> wrote:
> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
>
> Add clock and reset entries for the DSI and LCDC peripherals.
>
> Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

Thanks for your patch!

> --- a/drivers/clk/renesas/r9a09g057-cpg.c
> +++ b/drivers/clk/renesas/r9a09g057-cpg.c

> @@ -58,6 +60,9 @@ enum clk_ids {
>         CLK_SMUX2_GBE0_RXCLK,
>         CLK_SMUX2_GBE1_TXCLK,
>         CLK_SMUX2_GBE1_RXCLK,
> +       CLK_DIV_PLLETH_LPCLK,

CLK_CDIV4_PLLETH_LPCLK?

> +       CLK_CSDIV_PLLETH_LPCLK,

CLK_PLLETH_LPCLK_GEAR?

> +       CLK_PLLDSI_SDIV2,

CLK_PLLDSI_GEAR?

>         CLK_PLLGPU_GEAR,
>
>         /* Module Clocks */

> @@ -148,6 +182,12 @@ static const struct cpg_core_clk r9a09g057_core_clks[] __initconst = {
>         DEF_SMUX(".smux2_gbe0_rxclk", CLK_SMUX2_GBE0_RXCLK, SSEL0_SELCTL3, smux2_gbe0_rxclk),
>         DEF_SMUX(".smux2_gbe1_txclk", CLK_SMUX2_GBE1_TXCLK, SSEL1_SELCTL0, smux2_gbe1_txclk),
>         DEF_SMUX(".smux2_gbe1_rxclk", CLK_SMUX2_GBE1_RXCLK, SSEL1_SELCTL1, smux2_gbe1_rxclk),
> +       DEF_FIXED(".cdiv4_plleth_lpclk", CLK_DIV_PLLETH_LPCLK, CLK_PLLETH, 1, 4),
> +       DEF_CSDIV(".plleth_lpclk_gear", CLK_CSDIV_PLLETH_LPCLK, CLK_DIV_PLLETH_LPCLK,
> +                 CSDIV0_DIVCTL2, dtable_16_128),
> +
> +       DEF_PLLDSI_DIV(".plldsi_sdiv2", CLK_PLLDSI_SDIV2, CLK_PLLDSI,

".plldsi_gear", CLK_PLLDSI_GEAR ...


> +                      CSDIV1_DIVCTL2, dtable_2_32),
>
>         DEF_DDIV(".pllgpu_gear", CLK_PLLGPU_GEAR, CLK_PLLGPU, CDDIV3_DIVCTL1, dtable_2_64),
>

The rest LGTM.

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

^ permalink raw reply	[flat|nested] 18+ messages in thread

* Re: [PATCH v5 3/4] dt-bindings: display: bridge: renesas,dsi: Add support for RZ/V2H(P) SoC
  2025-05-12 18:43 ` [PATCH v5 3/4] dt-bindings: display: bridge: renesas, dsi: Add support for RZ/V2H(P) SoC Prabhakar
@ 2025-05-23 14:58   ` Geert Uytterhoeven
  2025-05-27 22:04     ` Lad, Prabhakar
  0 siblings, 1 reply; 18+ messages in thread
From: Geert Uytterhoeven @ 2025-05-23 14:58 UTC (permalink / raw)
  To: Prabhakar
  Cc: Andrzej Hajda, Neil Armstrong, Robert Foss, Laurent Pinchart,
	Jonas Karlman, Jernej Skrabec, David Airlie, Simona Vetter,
	Maarten Lankhorst, Maxime Ripard, Thomas Zimmermann, Rob Herring,
	Krzysztof Kozlowski, Conor Dooley, Michael Turquette,
	Stephen Boyd, Biju Das, Magnus Damm, dri-devel, devicetree,
	linux-kernel, linux-renesas-soc, linux-clk, Fabrizio Castro,
	Lad Prabhakar, Krzysztof Kozlowski

Hi Prabhakar,

On Mon, 12 May 2025 at 20:43, Prabhakar <prabhakar.csengg@gmail.com> wrote:
> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
>
> The MIPI DSI interface on the RZ/V2H(P) SoC is nearly identical to that of
> the RZ/G2L SoC. While the LINK registers are the same for both SoCs, the
> D-PHY registers differ. Additionally, the number of resets for DSI on
> RZ/V2H(P) is two compared to three on the RZ/G2L.
>
> To accommodate these differences, a SoC-specific
> `renesas,r9a09g057-mipi-dsi` compatible string has been added for the
> RZ/V2H(P) SoC.
>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

Thanks for your patch!

> --- a/Documentation/devicetree/bindings/display/bridge/renesas,dsi.yaml
> +++ b/Documentation/devicetree/bindings/display/bridge/renesas,dsi.yaml
> @@ -14,16 +14,17 @@ description: |
>    RZ/G2L alike family of SoC's. The encoder can operate in DSI mode, with
>    up to four data lanes.
>
> -allOf:
> -  - $ref: /schemas/display/dsi-controller.yaml#
> -
>  properties:
>    compatible:
> -    items:
> +    oneOf:
>        - enum:
> -          - renesas,r9a07g044-mipi-dsi # RZ/G2{L,LC}
> -          - renesas,r9a07g054-mipi-dsi # RZ/V2L
> -      - const: renesas,rzg2l-mipi-dsi
> +          - renesas,r9a09g057-mipi-dsi # RZ/V2H(P)

Nit: I would add the new entry after all the old entries, to preserve
sort order (by part number).

> +
> +      - items:
> +          - enum:
> +              - renesas,r9a07g044-mipi-dsi # RZ/G2{L,LC}
> +              - renesas,r9a07g054-mipi-dsi # RZ/V2L
> +          - const: renesas,rzg2l-mipi-dsi
>
>    reg:
>      maxItems: 1

The rest LGTM, so
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

^ permalink raw reply	[flat|nested] 18+ messages in thread

* Re: [PATCH v5 4/4] drm: renesas: rz-du: mipi_dsi: Add support for RZ/V2H(P) SoC
  2025-05-12 18:43 ` [PATCH v5 4/4] drm: renesas: rz-du: mipi_dsi: " Prabhakar
@ 2025-05-23 15:18   ` Geert Uytterhoeven
  2025-05-28  9:48     ` Lad, Prabhakar
  0 siblings, 1 reply; 18+ messages in thread
From: Geert Uytterhoeven @ 2025-05-23 15:18 UTC (permalink / raw)
  To: Prabhakar, Fabrizio Castro
  Cc: Andrzej Hajda, Neil Armstrong, Robert Foss, Laurent Pinchart,
	Jonas Karlman, Jernej Skrabec, David Airlie, Simona Vetter,
	Maarten Lankhorst, Maxime Ripard, Thomas Zimmermann, Rob Herring,
	Krzysztof Kozlowski, Conor Dooley, Michael Turquette,
	Stephen Boyd, Biju Das, Magnus Damm, dri-devel, devicetree,
	linux-kernel, linux-renesas-soc, linux-clk, Lad Prabhakar

Hi Prabhakar, Fabrizio,

On Mon, 12 May 2025 at 20:43, Prabhakar <prabhakar.csengg@gmail.com> wrote:
> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
>
> Add DSI support for Renesas RZ/V2H(P) SoC.
>
> Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

Thanks for your patch!

> --- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> +++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> @@ -5,6 +5,7 @@
>   * Copyright (C) 2022 Renesas Electronics Corporation
>   */
>  #include <linux/clk.h>
> +#include <linux/clk/renesas-rzv2h-dsi.h>
>  #include <linux/delay.h>
>  #include <linux/io.h>
>  #include <linux/iopoll.h>
> @@ -30,6 +31,9 @@
>
>  #define RZ_MIPI_DSI_FEATURE_16BPP      BIT(0)
>
> +#define RZV2H_MIPI_DPHY_FOUT_MIN_IN_MEGA       (80 * MEGA)
> +#define RZV2H_MIPI_DPHY_FOUT_MAX_IN_MEGA       (1500 * MEGA)

RZV2H_MIPI_DPHY_FOUT_M{IN,AX}_IN_MHZ?

> +
>  struct rzg2l_mipi_dsi;
>
>  struct rzg2l_mipi_dsi_hw_info {
> @@ -40,6 +44,7 @@ struct rzg2l_mipi_dsi_hw_info {
>                               u64 *hsfreq_millihz);
>         unsigned int (*dphy_mode_clk_check)(struct rzg2l_mipi_dsi *dsi,
>                                             unsigned long mode_freq);
> +       const struct rzv2h_pll_div_limits *cpg_dsi_limits;
>         u32 phy_reg_offset;
>         u32 link_reg_offset;
>         unsigned long max_dclk;
> @@ -47,6 +52,11 @@ struct rzg2l_mipi_dsi_hw_info {
>         u8 features;
>  };
>
> +struct rzv2h_dsi_mode_calc {
> +       unsigned long mode_freq;
> +       u64 mode_freq_hz;

Interesting... I guess mode_freq is not in Hz?

> +};
> +
>  struct rzg2l_mipi_dsi {
>         struct device *dev;
>         void __iomem *mmio;

> +static u16 rzv2h_dphy_find_ulpsexit(unsigned long freq)
> +{
> +       static const unsigned long hsfreq[] = {
> +               1953125UL,
> +               3906250UL,
> +               7812500UL,
> +               15625000UL,
> +       };
> +       static const u16 ulpsexit[] = {49, 98, 195, 391};
> +       unsigned int i;
> +
> +       for (i = 0; i < ARRAY_SIZE(hsfreq); i++) {
> +               if (freq <= hsfreq[i])
> +                       break;
> +       }
> +
> +       if (i == ARRAY_SIZE(hsfreq))
> +               i -= 1;

i--

> +
> +       return ulpsexit[i];
> +}
> +
> +static u16 rzv2h_dphy_find_timings_val(unsigned long freq, u8 index)
> +{
> +       const struct rzv2h_mipi_dsi_timings *timings;
> +       u16 i;
> +
> +       timings = &rzv2h_dsi_timings_tables[index];
> +       for (i = 0; i < timings->len; i++) {
> +               unsigned long hsfreq = timings->hsfreq[i] * 10000000UL;

(I wanted to say "MEGA", but then I noticed the 7th zero ;-)

10 * MEGA?

> +
> +               if (freq <= hsfreq)
> +                       break;
> +       }
> +
> +       if (i == timings->len)
> +               i -= 1;

i--

> +
> +       return timings->start_index + i;
> +};
> +
>  static void rzg2l_mipi_dsi_phy_write(struct rzg2l_mipi_dsi *dsi, u32 reg, u32 data)
>  {
>         iowrite32(data, dsi->mmio + dsi->info->phy_reg_offset + reg);
> @@ -308,6 +479,158 @@ static int rzg2l_dphy_conf_clks(struct rzg2l_mipi_dsi *dsi, unsigned long mode_f
>         return 0;
>  }
>
> +static unsigned int rzv2h_dphy_mode_clk_check(struct rzg2l_mipi_dsi *dsi,
> +                                             unsigned long mode_freq)
> +{
> +       struct rzv2h_plldsi_parameters *dsi_parameters = &dsi->dsi_parameters;
> +       u64 hsfreq_millihz, mode_freq_hz, mode_freq_millihz;
> +       struct rzv2h_plldsi_parameters cpg_dsi_parameters;
> +       unsigned int bpp, i;
> +
> +       bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
> +
> +       for (i = 0; i < 10; i += 1) {
> +               unsigned long hsfreq;
> +               bool parameters_found;
> +
> +               mode_freq_hz = mode_freq * MILLI + i;

KILO?

And I guess you want to use mul_u32_u32(), as mode_freq_hz is u64?

> +               mode_freq_millihz = mode_freq_hz * MILLI * 1ULL;

Why * 1ULL?

> +               parameters_found = rzv2h_dsi_get_pll_parameters_values(dsi->info->cpg_dsi_limits,
> +                                                                      &cpg_dsi_parameters,
> +                                                                      mode_freq_millihz);
> +               if (!parameters_found)
> +                       continue;
> +
> +               hsfreq_millihz = DIV_ROUND_CLOSEST_ULL(cpg_dsi_parameters.freq_millihz * bpp,
> +                                                      dsi->lanes);
> +               parameters_found = rzv2h_dsi_get_pll_parameters_values(&rzv2h_plldsi_div_limits,
> +                                                                      dsi_parameters,
> +                                                                      hsfreq_millihz);
> +               if (!parameters_found)
> +                       continue;
> +
> +               if (abs(dsi_parameters->error_millihz) >= 500)
> +                       continue;
> +
> +               hsfreq = DIV_ROUND_CLOSEST_ULL(hsfreq_millihz, MILLI);
> +               if (hsfreq >= RZV2H_MIPI_DPHY_FOUT_MIN_IN_MEGA &&
> +                   hsfreq <= RZV2H_MIPI_DPHY_FOUT_MAX_IN_MEGA) {
> +                       dsi->mode_calc.mode_freq_hz = mode_freq_hz;
> +                       dsi->mode_calc.mode_freq = mode_freq;
> +                       return MODE_OK;
> +               }
> +       }
> +
> +       return MODE_CLOCK_RANGE;
> +}

> --- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi_regs.h
> +++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi_regs.h
> @@ -40,6 +40,39 @@
>  #define DSIDPHYTIM3_THS_TRAIL(x)       ((x) << 8)
>  #define DSIDPHYTIM3_THS_ZERO(x)                ((x) << 0)
>
> +/* RZ/V2H DPHY Registers */
> +#define PLLENR                         0x000
> +#define PLLENR_PLLEN                   BIT(0)
> +
> +#define PHYRSTR                                0x004
> +#define PHYRSTR_PHYMRSTN               BIT(0)
> +
> +#define PLLCLKSET0R                    0x010
> +#define PLLCLKSET0R_PLL_S(x)           ((x) << 0)

 #define PLLCLKSET0R_PLL_S GENMASK(2, 0)

and after that you can use FIELD_PREP(PLLCLKSET0R_PLL_S, x) in the code.
More opportunities for masks below...

> +#define PLLCLKSET0R_PLL_P(x)           ((x) << 8)
> +#define PLLCLKSET0R_PLL_M(x)           ((x) << 16)
> +
> +#define PLLCLKSET1R                    0x014
> +#define PLLCLKSET1R_PLL_K(x)           ((x) << 0)
> +
> +#define PHYTCLKSETR                    0x020
> +#define PHYTCLKSETR_TCLKTRAILCTL(x)    ((x) << 0)
> +#define PHYTCLKSETR_TCLKPOSTCTL(x)     ((x) << 8)
> +#define PHYTCLKSETR_TCLKZEROCTL(x)     ((x) << 16)
> +#define PHYTCLKSETR_TCLKPRPRCTL(x)     ((x) << 24)
> +
> +#define PHYTHSSETR                     0x024
> +#define PHYTHSSETR_THSEXITCTL(x)       ((x) << 0)
> +#define PHYTHSSETR_THSTRAILCTL(x)      ((x) << 8)
> +#define PHYTHSSETR_THSZEROCTL(x)       ((x) << 16)
> +#define PHYTHSSETR_THSPRPRCTL(x)       ((x) << 24)
> +
> +#define PHYTLPXSETR                    0x028
> +#define PHYTLPXSETR_TLPXCTL(x)         ((x) << 0)
> +
> +#define PHYCR                          0x030
> +#define PHYCR_ULPSEXIT(x)              ((x) << 0)
> +
>  /* --------------------------------------------------------*/
>
>  /* Link Status Register */

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

^ permalink raw reply	[flat|nested] 18+ messages in thread

* Re: [PATCH v5 1/4] clk: renesas: rzv2h-cpg: Add support for DSI clocks
  2025-05-23 14:45   ` Geert Uytterhoeven
@ 2025-05-27 21:50     ` Lad, Prabhakar
  2025-05-28  7:09       ` Geert Uytterhoeven
  0 siblings, 1 reply; 18+ messages in thread
From: Lad, Prabhakar @ 2025-05-27 21:50 UTC (permalink / raw)
  To: Geert Uytterhoeven
  Cc: Fabrizio Castro, Andrzej Hajda, Neil Armstrong, Robert Foss,
	Laurent Pinchart, Jonas Karlman, Jernej Skrabec, David Airlie,
	Simona Vetter, Maarten Lankhorst, Maxime Ripard,
	Thomas Zimmermann, Rob Herring, Krzysztof Kozlowski, Conor Dooley,
	Michael Turquette, Stephen Boyd, Biju Das, Magnus Damm, dri-devel,
	devicetree, linux-kernel, linux-renesas-soc, linux-clk,
	Lad Prabhakar

Hi Geert,

Thank you for the review.

On Fri, May 23, 2025 at 3:45 PM Geert Uytterhoeven <geert@linux-m68k.org> wrote:
>
> Hi Prabhakar, Fabrizio,
>
> On Mon, 12 May 2025 at 20:43, Prabhakar <prabhakar.csengg@gmail.com> wrote:
> > From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> >
> > Add support for PLLDSI and PLLDSI divider clocks.
> >
> > Introduce the `renesas-rzv2h-dsi.h` header to centralize and share
> > PLLDSI-related data structures, limits, and algorithms between the RZ/V2H
> > 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@renesas.com>
> > Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
>
> Thanks for your patch!
>
> > --- a/drivers/clk/renesas/rzv2h-cpg.c
> > +++ b/drivers/clk/renesas/rzv2h-cpg.c
> > @@ -48,6 +53,7 @@
> >  #define CPG_PLL_STBY(x)                ((x))
> >  #define CPG_PLL_STBY_RESETB    BIT(0)
> >  #define CPG_PLL_STBY_RESETB_WEN        BIT(16)
> > +#define CPG_PLL_STBY_SSCGEN_WEN BIT(18)
>
> CPG_PLL_STBY_SSC_EN_WEN?
>
OK, I will rename it as above.

> >  #define CPG_PLL_CLK1(x)                ((x) + 0x004)
> >  #define CPG_PLL_CLK1_KDIV(x)   ((s16)FIELD_GET(GENMASK(31, 16), (x)))
>
> You are already using FIELD_GET() for extracting the K, M, P, and
> S fields, but are still still open-coding shifts for writing in
> rzv2h_cpg_pll_set_rate().
>
> What about replacing CPG_PLL_CLK1_KDIV() by:
>
>     #define CPG_PLL_CLK1_DIV_K    GENMASK(31,16)
>
> Then the code can use:
>
>     (s16)FIELD_GET(CPG_PLL_CLK1_DIV_K, clk1)
>
> for reading and:
>
>     FIELD_PREP(CPG_PLL_CLK1_DIV_K, (u16)k) | ...
>
> for writing?
>
> Same for the M, P, and S fields (but without the s16/u16 casts, as
> they are unsigned, unlike K).
>
Ok, I will update the macros as below:
#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_SDIV      GENMASK(2, 0)

> >  #define CPG_PLL_CLK1_MDIV(x)   FIELD_GET(GENMASK(15, 6), (x))
>
> > @@ -198,6 +227,188 @@ static int rzv2h_cpg_pll_clk_enable(struct clk_hw *hw)
> >         return ret;
> >  }
> >
> > +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 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_plldsi_parameters *dsi_dividers = &priv->plldsi_div_parameters;
> > +       u64 rate_millihz;
> > +
> > +       /*
> > +        * Adjust the requested clock rate (`req->rate`) to ensure it falls within
> > +        * the supported range of 5.44 MHz to 187.5 MHz.
> > +        */
> > +       req->rate = clamp(req->rate, 5440000UL, 187500000UL);
> > +
> > +       rate_millihz = mul_u32_u32(req->rate, MILLI);
> > +       if (rate_millihz == dsi_dividers->error_millihz + dsi_dividers->freq_millihz)
> > +               goto exit_determine_rate;
> > +
> > +       if (!rzv2h_dsi_get_pll_parameters_values(priv->dsi_limits,
> > +                                                dsi_dividers, rate_millihz)) {
> > +               dev_err(priv->dev,
> > +                       "failed to determine rate for req->rate: %lu\n",
> > +                       req->rate);
> > +               return -EINVAL;
> > +       }
> > +
> > +exit_determine_rate:
> > +       req->best_parent_rate = req->rate * dsi_dividers->csdiv;
>
> Shouldn't this also update req->rate with the actual rate?
>
>     req->rate = DIV_ROUND_CLOSEST_ULL(dsi_dividers->freq_millihz, MILLI);
>
Agreed, I will update it.

> Would it help the DSI driver if this clock would provide a
> .recalc_accuracy() callback that takes into account the difference
> between req->rate and dsi_dividers->freq_millihz?
> Or would that be considered abuse of the accuracy concept?
>
Our understanding is that this describes how precisely a clock keeps
time. A clock with 1 ppb accuracy will gain or lose one second in
approximately 31.5 million seconds (1 year). In our case the meaning
is completely different.

> > +
> > +       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_plldsi_parameters *dsi_dividers = &priv->plldsi_div_parameters;
> > +       struct ddiv ddiv = dsi_div->ddiv;
> > +       const struct clk_div_table *clkt;
> > +       bool div_found = false;
> > +       u32 val, shift, div;
> > +
> > +       div = dsi_dividers->csdiv;
> > +       for (clkt = dsi_div->dtable; clkt->div; clkt++) {
> > +               if (clkt->div == div) {
> > +                       div_found = true;
> > +                       break;
> > +               }
> > +       }
> > +
> > +       if (!div_found)
> > +               return -EINVAL;
> > +
> > +       shift = ddiv.shift;
> > +       val = readl(priv->base + ddiv.offset) | DDIV_DIVCTL_WEN(shift);
> > +       val &= ~(clk_div_mask(ddiv.width) << shift);
> > +       val |= (u32)clkt->val << shift;
>
> No need for the cast.
>
Agreed, I will drop it.

> > +       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 long rzv2h_cpg_plldsi_round_rate(struct clk_hw *hw,
> > +                                       unsigned long rate,
> > +                                       unsigned long *parent_rate)
> > +{
> > +       return clamp(rate, 25000000UL, 375000000UL);
>
> This only brings the desired rate into the supported range, but does
> not round it to the nearest rate that is actually supported.
>
Agreed. Actually I'll replace round rate with .determine_rate() for
the next iteration.

> > +}
> > +
> > +static int rzv2h_cpg_pll_set_rate(struct clk_hw *hw,
> > +                                 unsigned long rate,
> > +                                 unsigned long parent_rate)
> > +{
> > +       struct pll_clk *pll_clk = to_pll(hw);
> > +       struct rzv2h_cpg_priv *priv = pll_clk->priv;
> > +       struct rzv2h_plldsi_parameters *dsi_dividers;
> > +       struct pll pll = pll_clk->pll;
> > +       u16 offset = 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;
> > +       }
> > +
> > +       dsi_dividers = &priv->plldsi_div_parameters;
> > +       /* Output clock setting 1 */
> > +       writel((dsi_dividers->k << 16) | (dsi_dividers->m << 6) | (dsi_dividers->p),
>
> This is where you want to use FIELD_PREP().
>
Ok, I'll replace it with below:
       writel(FIELD_PREP(CPG_PLL_CLK1_KDIV, (u16)dsi_dividers->k) |
             FIELD_PREP(CPG_PLL_CLK1_MDIV, dsi_dividers->m) |
             FIELD_PREP(CPG_PLL_CLK1_PDIV, dsi_dividers->p),
             priv->base + CPG_PLL_CLK1(offset));

> > +              priv->base + CPG_PLL_CLK1(offset));
> > +
> > +       /* Output clock setting 2 */
> > +       val = readl(priv->base + CPG_PLL_CLK2(offset));
> > +       writel((val & ~GENMASK(2, 0)) | dsi_dividers->s,
>
> (val & ~CPG_PLL_CLK2_DIV_S) | FIELD_PREP(...)
>
Agreed, I will replace it with `writel((val & ~CPG_PLL_CLK2_SDIV) |
FIELD_PREP(CPG_PLL_CLK2_SDIV, dsi_dividers->s),`

> > +              priv->base + CPG_PLL_CLK2(offset));
> > +
> > +       /* Put PLL to normal mode */
> > +       writel(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 unsigned long rzv2h_cpg_pll_clk_recalc_rate(struct clk_hw *hw,
> >                                                    unsigned long parent_rate)
> >  {
>
> > --- a/drivers/clk/renesas/rzv2h-cpg.h
> > +++ b/drivers/clk/renesas/rzv2h-cpg.h
> > @@ -100,6 +100,7 @@ struct smuxed {
> >  #define CPG_CDDIV3             (0x40C)
> >  #define CPG_CDDIV4             (0x410)
> >  #define CPG_CSDIV0             (0x500)
> > +#define CPG_CSDIV1             (0x504)
>
> Unused until [PATCH v5 2/4], so please move it there.
>
I'll move this patch 2/4

> >
> >  #define CDDIV0_DIVCTL1 DDIV_PACK(CPG_CDDIV0, 4, 3, 1)
> >  #define CDDIV0_DIVCTL2 DDIV_PACK(CPG_CDDIV0, 8, 3, 2)
>
> > --- /dev/null
> > +++ b/include/linux/clk/renesas-rzv2h-dsi.h
> > @@ -0,0 +1,211 @@
> > +/* SPDX-License-Identifier: GPL-2.0 */
> > +/*
> > + * Renesas RZ/V2H(P) DSI CPG helper
> > + *
> > + * Copyright (C) 2025 Renesas Electronics Corp.
> > + */
> > +#ifndef __RENESAS_RZV2H_DSI_H__
> > +#define __RENESAS_RZV2H_DSI_H__
> > +
> > +#include <linux/limits.h>
> > +#include <linux/math.h>
> > +#include <linux/math64.h>
> > +#include <linux/units.h>
> > +
> > +#define OSC_CLK_IN_MEGA                (24 * MEGA)
> > +
> > +struct rzv2h_pll_div_limits {
> > +       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 {
> > +               u8 min;
> > +               u8 max;
> > +       } csdiv;
> > +};
> > +
> > +struct rzv2h_plldsi_parameters {
> > +       u64 freq_millihz;
> > +       s64 error_millihz;
> > +       u16 m;
> > +       s16 k;
> > +       u8 csdiv;
> > +       u8 p;
> > +       u8 s;
> > +};
> > +
> > +#define RZV2H_CPG_PLL_DSI_LIMITS(name)                                 \
> > +       static const struct rzv2h_pll_div_limits (name) = {             \
> > +               .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 },                   \
> > +               .csdiv = { .min = 2, .max = 32 },                       \
> > +       }                                                               \
> > +
> > +/**
> > + * rzv2h_dsi_get_pll_parameters_values - 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 and
> > + * divider values
> > + * @pars: Pointer to the structure where the best calculated PLL parameters and divider
> > + * values will be stored
> > + * @freq_millihz: Target output frequency in millihertz
> > + *
> > + * This function calculates the best set of PLL parameters (M, K, P, S) and divider
> > + * value (CSDIV) to achieve the desired frequency.
> > + * There is no direct formula to calculate the PLL parameters and the divider value,
> > + * 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 divider values is found, false otherwise.
> > + */
> > +static __maybe_unused bool
> > +rzv2h_dsi_get_pll_parameters_values(const struct rzv2h_pll_div_limits *limits,
> > +                                   struct rzv2h_plldsi_parameters *pars,
> > +                                   u64 freq_millihz)
> > +{
> > +       struct rzv2h_plldsi_parameters p, best;
> > +
> > +       /* Initialize best error to maximum possible value */
> > +       best.error_millihz = S64_MAX;
> > +
> > +       for (p.csdiv = limits->csdiv.min; p.csdiv <= limits->csdiv.max; p.csdiv += 2) {
> > +               for (p.p = limits->p.min; p.p <= limits->p.max; p.p++) {
> > +                       u32 fref = OSC_CLK_IN_MEGA / p.p;
> > +
> > +                       for (p.s = limits->s.min; p.s <= limits->s.max; p.s++) {
> > +                               u16 two_pow_s = 1 << p.s;
> > +                               u16 divider = two_pow_s * p.csdiv;
>
> No need for two_pow_s.  You can initialize divider = p.csdiv << s.min
> at the start of the loop, and multiply by two after each iteration.
>
Agreed, I'll replace it with something like below:

                       for (divider = p.csdiv << limits->s.min, p.s =
limits->s.min;
                            p.s <= limits->s.max; p.s++, divider *= 2) {

> > +
> > +                               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 combination of the
> > +                                        * PLL + divider is calculated as follows:
> > +                                        *
> > +                                        * Freq = Ffout / csdiv
> > +                                        *
> > +                                        * With:
> > +                                        * 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) * csdiv))
> > +                                        *      = Ffvco / divider
> > +                                        *      = (pll_m * Ffref) / divider + ((pll_k / 65536) * Ffref) / divider
> > +                                        *      = output_m + output_k
> > +                                        *
> > +                                        * Every parameter has been determined at this point, but pll_k.
> > +                                        * Considering that:
> > +                                        * -32768 <= pll_k <= 32767
> > +                                        * Then:
> > +                                        * -0.5 <= (pll_k / 65536) < 0.5
> > +                                        * Therefore:
> > +                                        * -Ffref / (2 * divider) <= output_k < Ffref / (2 * divider)
> > +                                        */
> > +
> > +                                       /* Compute output M component (in mHz) */
> > +                                       output_m = DIV_ROUND_CLOSEST_ULL(p.m * fref * 1000ULL,
>
> "p.m * fref" may overflow => mul_u32_u32(p.m, fref) * MILLI;
>
Agreed, I'll switch to mul_u32_u32().

> > +                                                                        divider);
> > +                                       /* Compute range for output K (in mHz) */
> > +                                       output_k_range = DIV_ROUND_CLOSEST_ULL(fref * 1000ULL,
>
> mul_u32_u32(fref, MILLI)
>
OK.

> > +                                                                              divider * 2);
> > +                                       /*
> > +                                        * 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) / divider
> > +                                        * Therefore:
> > +                                        * pll_k = (output_k * 65536 * divider) / Ffref
> > +                                        */
> > +                                       output_k = freq_millihz - output_m;
> > +                                       pll_k = div64_s64(output_k * 65536ULL * divider, fref);
>
> div_s64(), as fref is 32-bit.
>
OK.

> > +                                       pll_k = DIV_S64_ROUND_CLOSEST(pll_k, 1000);
>
> MILLI
>
OK.

> > +
> > +                                       /* 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 = ((p.m * 65536ULL) + p.k) * fref;
>
> mul_u32(p.m * 65536 + p.k, fref)
>
OK, I'll switch to the above.

> I guess the compiler is sufficiently smart to turn that into a shift.
> The alternative would be to use a cast (I try to avoid them) and a shift:
>
> mul_u32((u64)p.m << 16 + p.k, fref)
>
> > +                                       if ((fvco < (limits->fvco.min * 65536ULL)) ||
> > +                                           (fvco > (limits->fvco.max * 65536ULL)))
>
> mul_u32_u32(..., 65536) for both
>
Agreed.

> > +                                               continue;
> > +
> > +                                       /* PLL_M component of (output * 65536 * PLL_P) */
> > +                                       output = p.m * 65536ULL * OSC_CLK_IN_MEGA;
>
> mul_u32(p.m * 65536, OSC_CLK_IN_MEGA)
>
OK, I'll switch to mul_u32_u32().

> > +                                       /* PLL_K component of (output * 65536 * PLL_P) */
> > +                                       output += p.k * OSC_CLK_IN_MEGA;
> > +                                       /* Make it in mHz */
> > +                                       output *= 1000ULL;
>
> No need for the ULL => MILLI
Agreed, I will drop it.

>
> > +                                       output /= 65536ULL * p.p * divider;
>
> mul_u32()
>
> No rounding for the division?
>
Indeed, we missed it. Actually I drop the mul_u32_u32() suggestion
just use the below:

output = DIV_U64_ROUND_CLOSEST(output, 65536 * p.p * divider);

Cheers,
Prabhakar

^ permalink raw reply	[flat|nested] 18+ messages in thread

* Re: [PATCH v5 2/4] clk: renesas: r9a09g057: Add clock and reset entries for DSI and LCDC
  2025-05-23 14:46   ` Geert Uytterhoeven
@ 2025-05-27 22:01     ` Lad, Prabhakar
  0 siblings, 0 replies; 18+ messages in thread
From: Lad, Prabhakar @ 2025-05-27 22:01 UTC (permalink / raw)
  To: Geert Uytterhoeven
  Cc: Fabrizio Castro, Andrzej Hajda, Neil Armstrong, Robert Foss,
	Laurent Pinchart, Jonas Karlman, Jernej Skrabec, David Airlie,
	Simona Vetter, Maarten Lankhorst, Maxime Ripard,
	Thomas Zimmermann, Rob Herring, Krzysztof Kozlowski, Conor Dooley,
	Michael Turquette, Stephen Boyd, Biju Das, Magnus Damm, dri-devel,
	devicetree, linux-kernel, linux-renesas-soc, linux-clk,
	Lad Prabhakar

Hi Geert,

Thank you for the review.

On Fri, May 23, 2025 at 3:46 PM Geert Uytterhoeven <geert@linux-m68k.org> wrote:
>
> Hi Prabhakar, Fabrizio,
>
> On Mon, 12 May 2025 at 20:43, Prabhakar <prabhakar.csengg@gmail.com> wrote:
> > From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> >
> > Add clock and reset entries for the DSI and LCDC peripherals.
> >
> > Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> > Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
>
> Thanks for your patch!
>
> > --- a/drivers/clk/renesas/r9a09g057-cpg.c
> > +++ b/drivers/clk/renesas/r9a09g057-cpg.c
>
> > @@ -58,6 +60,9 @@ enum clk_ids {
> >         CLK_SMUX2_GBE0_RXCLK,
> >         CLK_SMUX2_GBE1_TXCLK,
> >         CLK_SMUX2_GBE1_RXCLK,
> > +       CLK_DIV_PLLETH_LPCLK,
>
> CLK_CDIV4_PLLETH_LPCLK?
>
Agreed, I'll rename it as above.

> > +       CLK_CSDIV_PLLETH_LPCLK,
>
> CLK_PLLETH_LPCLK_GEAR?
>
Agreed, I'll rename it as above.

> > +       CLK_PLLDSI_SDIV2,
>
> CLK_PLLDSI_GEAR?
>
Agreed, I'll rename it as above.

> >         CLK_PLLGPU_GEAR,
> >
> >         /* Module Clocks */
>
> > @@ -148,6 +182,12 @@ static const struct cpg_core_clk r9a09g057_core_clks[] __initconst = {
> >         DEF_SMUX(".smux2_gbe0_rxclk", CLK_SMUX2_GBE0_RXCLK, SSEL0_SELCTL3, smux2_gbe0_rxclk),
> >         DEF_SMUX(".smux2_gbe1_txclk", CLK_SMUX2_GBE1_TXCLK, SSEL1_SELCTL0, smux2_gbe1_txclk),
> >         DEF_SMUX(".smux2_gbe1_rxclk", CLK_SMUX2_GBE1_RXCLK, SSEL1_SELCTL1, smux2_gbe1_rxclk),
> > +       DEF_FIXED(".cdiv4_plleth_lpclk", CLK_DIV_PLLETH_LPCLK, CLK_PLLETH, 1, 4),
> > +       DEF_CSDIV(".plleth_lpclk_gear", CLK_CSDIV_PLLETH_LPCLK, CLK_DIV_PLLETH_LPCLK,
> > +                 CSDIV0_DIVCTL2, dtable_16_128),
> > +
> > +       DEF_PLLDSI_DIV(".plldsi_sdiv2", CLK_PLLDSI_SDIV2, CLK_PLLDSI,
>
> ".plldsi_gear", CLK_PLLDSI_GEAR ...
>
Agreed, I'll rename it as above.

Cheers,
Prabhakar

>
> > +                      CSDIV1_DIVCTL2, dtable_2_32),
> >
> >         DEF_DDIV(".pllgpu_gear", CLK_PLLGPU_GEAR, CLK_PLLGPU, CDDIV3_DIVCTL1, dtable_2_64),
> >
>
> The rest LGTM.
>
> Gr{oetje,eeting}s,
>
>                         Geert
>
> --
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
>
> In personal conversations with technical people, I call myself a hacker. But
> when I'm talking to journalists I just say "programmer" or something like that.
>                                 -- Linus Torvalds

^ permalink raw reply	[flat|nested] 18+ messages in thread

* Re: [PATCH v5 3/4] dt-bindings: display: bridge: renesas,dsi: Add support for RZ/V2H(P) SoC
  2025-05-23 14:58   ` [PATCH v5 3/4] dt-bindings: display: bridge: renesas,dsi: " Geert Uytterhoeven
@ 2025-05-27 22:04     ` Lad, Prabhakar
  0 siblings, 0 replies; 18+ messages in thread
From: Lad, Prabhakar @ 2025-05-27 22:04 UTC (permalink / raw)
  To: Geert Uytterhoeven
  Cc: Andrzej Hajda, Neil Armstrong, Robert Foss, Laurent Pinchart,
	Jonas Karlman, Jernej Skrabec, David Airlie, Simona Vetter,
	Maarten Lankhorst, Maxime Ripard, Thomas Zimmermann, Rob Herring,
	Krzysztof Kozlowski, Conor Dooley, Michael Turquette,
	Stephen Boyd, Biju Das, Magnus Damm, dri-devel, devicetree,
	linux-kernel, linux-renesas-soc, linux-clk, Fabrizio Castro,
	Lad Prabhakar, Krzysztof Kozlowski

Hi Geert,

Thank you for the review.

On Fri, May 23, 2025 at 3:58 PM Geert Uytterhoeven <geert@linux-m68k.org> wrote:
>
> Hi Prabhakar,
>
> On Mon, 12 May 2025 at 20:43, Prabhakar <prabhakar.csengg@gmail.com> wrote:
> > From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> >
> > The MIPI DSI interface on the RZ/V2H(P) SoC is nearly identical to that of
> > the RZ/G2L SoC. While the LINK registers are the same for both SoCs, the
> > D-PHY registers differ. Additionally, the number of resets for DSI on
> > RZ/V2H(P) is two compared to three on the RZ/G2L.
> >
> > To accommodate these differences, a SoC-specific
> > `renesas,r9a09g057-mipi-dsi` compatible string has been added for the
> > RZ/V2H(P) SoC.
> >
> > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> > Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
>
> Thanks for your patch!
>
> > --- a/Documentation/devicetree/bindings/display/bridge/renesas,dsi.yaml
> > +++ b/Documentation/devicetree/bindings/display/bridge/renesas,dsi.yaml
> > @@ -14,16 +14,17 @@ description: |
> >    RZ/G2L alike family of SoC's. The encoder can operate in DSI mode, with
> >    up to four data lanes.
> >
> > -allOf:
> > -  - $ref: /schemas/display/dsi-controller.yaml#
> > -
> >  properties:
> >    compatible:
> > -    items:
> > +    oneOf:
> >        - enum:
> > -          - renesas,r9a07g044-mipi-dsi # RZ/G2{L,LC}
> > -          - renesas,r9a07g054-mipi-dsi # RZ/V2L
> > -      - const: renesas,rzg2l-mipi-dsi
> > +          - renesas,r9a09g057-mipi-dsi # RZ/V2H(P)
>
> Nit: I would add the new entry after all the old entries, to preserve
> sort order (by part number).
>
I'll move that later to preserve the sort order in the next version.

Cheers,
Prabhakar

> > +
> > +      - items:
> > +          - enum:
> > +              - renesas,r9a07g044-mipi-dsi # RZ/G2{L,LC}
> > +              - renesas,r9a07g054-mipi-dsi # RZ/V2L
> > +          - const: renesas,rzg2l-mipi-dsi
> >
> >    reg:
> >      maxItems: 1
>
> The rest LGTM, so
> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
>
> Gr{oetje,eeting}s,
>
>                         Geert
>
> --
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
>
> In personal conversations with technical people, I call myself a hacker. But
> when I'm talking to journalists I just say "programmer" or something like that.
>                                 -- Linus Torvalds

^ permalink raw reply	[flat|nested] 18+ messages in thread

* Re: [PATCH v5 1/4] clk: renesas: rzv2h-cpg: Add support for DSI clocks
  2025-05-27 21:50     ` Lad, Prabhakar
@ 2025-05-28  7:09       ` Geert Uytterhoeven
  2025-05-28 14:13         ` Lad, Prabhakar
  0 siblings, 1 reply; 18+ messages in thread
From: Geert Uytterhoeven @ 2025-05-28  7:09 UTC (permalink / raw)
  To: Lad, Prabhakar
  Cc: Fabrizio Castro, Andrzej Hajda, Neil Armstrong, Robert Foss,
	Laurent Pinchart, Jonas Karlman, Jernej Skrabec, David Airlie,
	Simona Vetter, Maarten Lankhorst, Maxime Ripard,
	Thomas Zimmermann, Rob Herring, Krzysztof Kozlowski, Conor Dooley,
	Michael Turquette, Stephen Boyd, Biju Das, Magnus Damm, dri-devel,
	devicetree, linux-kernel, linux-renesas-soc, linux-clk,
	Lad Prabhakar

Hi Prabhakar,

On Tue, 27 May 2025 at 23:51, Lad, Prabhakar <prabhakar.csengg@gmail.com> wrote:
> On Fri, May 23, 2025 at 3:45 PM Geert Uytterhoeven <geert@linux-m68k.org> wrote:
> > On Mon, 12 May 2025 at 20:43, Prabhakar <prabhakar.csengg@gmail.com> wrote:
> > > From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> > >
> > > Add support for PLLDSI and PLLDSI divider clocks.
> > >
> > > Introduce the `renesas-rzv2h-dsi.h` header to centralize and share
> > > PLLDSI-related data structures, limits, and algorithms between the RZ/V2H
> > > 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@renesas.com>
> > > Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> > > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

> > > +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_plldsi_parameters *dsi_dividers = &priv->plldsi_div_parameters;
> > > +       u64 rate_millihz;
> > > +
> > > +       /*
> > > +        * Adjust the requested clock rate (`req->rate`) to ensure it falls within
> > > +        * the supported range of 5.44 MHz to 187.5 MHz.
> > > +        */
> > > +       req->rate = clamp(req->rate, 5440000UL, 187500000UL);
> > > +
> > > +       rate_millihz = mul_u32_u32(req->rate, MILLI);
> > > +       if (rate_millihz == dsi_dividers->error_millihz + dsi_dividers->freq_millihz)
> > > +               goto exit_determine_rate;
> > > +
> > > +       if (!rzv2h_dsi_get_pll_parameters_values(priv->dsi_limits,
> > > +                                                dsi_dividers, rate_millihz)) {
> > > +               dev_err(priv->dev,
> > > +                       "failed to determine rate for req->rate: %lu\n",
> > > +                       req->rate);
> > > +               return -EINVAL;
> > > +       }
> > > +
> > > +exit_determine_rate:
> > > +       req->best_parent_rate = req->rate * dsi_dividers->csdiv;
> >
> > Shouldn't this also update req->rate with the actual rate?
> >
> >     req->rate = DIV_ROUND_CLOSEST_ULL(dsi_dividers->freq_millihz, MILLI);
> >
> Agreed, I will update it.

I think not updating req->rate may cause clk_get_rate() to return
an incorrect value (can error_millihz > 1000?).  Any chance this fix
can simplify the clock handling in the DSI driver?

> > Would it help the DSI driver if this clock would provide a
> > .recalc_accuracy() callback that takes into account the difference
> > between req->rate and dsi_dividers->freq_millihz?
> > Or would that be considered abuse of the accuracy concept?
> >
> Our understanding is that this describes how precisely a clock keeps
> time. A clock with 1 ppb accuracy will gain or lose one second in
> approximately 31.5 million seconds (1 year). In our case the meaning
> is completely different.

Yeah, I know...

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

^ permalink raw reply	[flat|nested] 18+ messages in thread

* Re: [PATCH v5 4/4] drm: renesas: rz-du: mipi_dsi: Add support for RZ/V2H(P) SoC
  2025-05-23 15:18   ` Geert Uytterhoeven
@ 2025-05-28  9:48     ` Lad, Prabhakar
  2025-05-28 12:31       ` Geert Uytterhoeven
  0 siblings, 1 reply; 18+ messages in thread
From: Lad, Prabhakar @ 2025-05-28  9:48 UTC (permalink / raw)
  To: Geert Uytterhoeven
  Cc: Fabrizio Castro, Andrzej Hajda, Neil Armstrong, Robert Foss,
	Laurent Pinchart, Jonas Karlman, Jernej Skrabec, David Airlie,
	Simona Vetter, Maarten Lankhorst, Maxime Ripard,
	Thomas Zimmermann, Rob Herring, Krzysztof Kozlowski, Conor Dooley,
	Michael Turquette, Stephen Boyd, Biju Das, Magnus Damm, dri-devel,
	devicetree, linux-kernel, linux-renesas-soc, linux-clk,
	Lad Prabhakar

Hi Geert,

Thank you for the review.

On Fri, May 23, 2025 at 4:19 PM Geert Uytterhoeven <geert@linux-m68k.org> wrote:
>
> Hi Prabhakar, Fabrizio,
>
> On Mon, 12 May 2025 at 20:43, Prabhakar <prabhakar.csengg@gmail.com> wrote:
> > From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> >
> > Add DSI support for Renesas RZ/V2H(P) SoC.
> >
> > Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> > Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
>
> Thanks for your patch!
>
> > --- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> > +++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> > @@ -5,6 +5,7 @@
> >   * Copyright (C) 2022 Renesas Electronics Corporation
> >   */
> >  #include <linux/clk.h>
> > +#include <linux/clk/renesas-rzv2h-dsi.h>
> >  #include <linux/delay.h>
> >  #include <linux/io.h>
> >  #include <linux/iopoll.h>
> > @@ -30,6 +31,9 @@
> >
> >  #define RZ_MIPI_DSI_FEATURE_16BPP      BIT(0)
> >
> > +#define RZV2H_MIPI_DPHY_FOUT_MIN_IN_MEGA       (80 * MEGA)
> > +#define RZV2H_MIPI_DPHY_FOUT_MAX_IN_MEGA       (1500 * MEGA)
>
> RZV2H_MIPI_DPHY_FOUT_M{IN,AX}_IN_MHZ?
>
Ok, I'll rename them as above.

> > +
> >  struct rzg2l_mipi_dsi;
> >
> >  struct rzg2l_mipi_dsi_hw_info {
> > @@ -40,6 +44,7 @@ struct rzg2l_mipi_dsi_hw_info {
> >                               u64 *hsfreq_millihz);
> >         unsigned int (*dphy_mode_clk_check)(struct rzg2l_mipi_dsi *dsi,
> >                                             unsigned long mode_freq);
> > +       const struct rzv2h_pll_div_limits *cpg_dsi_limits;
> >         u32 phy_reg_offset;
> >         u32 link_reg_offset;
> >         unsigned long max_dclk;
> > @@ -47,6 +52,11 @@ struct rzg2l_mipi_dsi_hw_info {
> >         u8 features;
> >  };
> >
> > +struct rzv2h_dsi_mode_calc {
> > +       unsigned long mode_freq;
> > +       u64 mode_freq_hz;
>
> Interesting... I guess mode_freq is not in Hz?
>
Actually it is int Hz, I will make it unsigned long.

> > +};
> > +
> >  struct rzg2l_mipi_dsi {
> >         struct device *dev;
> >         void __iomem *mmio;
>
> > +static u16 rzv2h_dphy_find_ulpsexit(unsigned long freq)
> > +{
> > +       static const unsigned long hsfreq[] = {
> > +               1953125UL,
> > +               3906250UL,
> > +               7812500UL,
> > +               15625000UL,
> > +       };
> > +       static const u16 ulpsexit[] = {49, 98, 195, 391};
> > +       unsigned int i;
> > +
> > +       for (i = 0; i < ARRAY_SIZE(hsfreq); i++) {
> > +               if (freq <= hsfreq[i])
> > +                       break;
> > +       }
> > +
> > +       if (i == ARRAY_SIZE(hsfreq))
> > +               i -= 1;
>
> i--
>
OK.

> > +
> > +       return ulpsexit[i];
> > +}
> > +
> > +static u16 rzv2h_dphy_find_timings_val(unsigned long freq, u8 index)
> > +{
> > +       const struct rzv2h_mipi_dsi_timings *timings;
> > +       u16 i;
> > +
> > +       timings = &rzv2h_dsi_timings_tables[index];
> > +       for (i = 0; i < timings->len; i++) {
> > +               unsigned long hsfreq = timings->hsfreq[i] * 10000000UL;
>
> (I wanted to say "MEGA", but then I noticed the 7th zero ;-)
>
> 10 * MEGA?
>
Agreed, I will update it as above.

> > +
> > +               if (freq <= hsfreq)
> > +                       break;
> > +       }
> > +
> > +       if (i == timings->len)
> > +               i -= 1;
>
> i--
>
> > +
> > +       return timings->start_index + i;
> > +};
> > +
> >  static void rzg2l_mipi_dsi_phy_write(struct rzg2l_mipi_dsi *dsi, u32 reg, u32 data)
> >  {
> >         iowrite32(data, dsi->mmio + dsi->info->phy_reg_offset + reg);
> > @@ -308,6 +479,158 @@ static int rzg2l_dphy_conf_clks(struct rzg2l_mipi_dsi *dsi, unsigned long mode_f
> >         return 0;
> >  }
> >
> > +static unsigned int rzv2h_dphy_mode_clk_check(struct rzg2l_mipi_dsi *dsi,
> > +                                             unsigned long mode_freq)
> > +{
> > +       struct rzv2h_plldsi_parameters *dsi_parameters = &dsi->dsi_parameters;
> > +       u64 hsfreq_millihz, mode_freq_hz, mode_freq_millihz;
> > +       struct rzv2h_plldsi_parameters cpg_dsi_parameters;
> > +       unsigned int bpp, i;
> > +
> > +       bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
> > +
> > +       for (i = 0; i < 10; i += 1) {
> > +               unsigned long hsfreq;
> > +               bool parameters_found;
> > +
> > +               mode_freq_hz = mode_freq * MILLI + i;
>
> KILO?
>
OK, as mode_freq_hz is in Hz I'll make it unsigned long.

> And I guess you want to use mul_u32_u32(), as mode_freq_hz is u64?
>
and use mul_u32_u32() below...
> > +               mode_freq_millihz = mode_freq_hz * MILLI * 1ULL;
>
> Why * 1ULL?
>
Agreed, not needed, I will use mul_u32_u32() here.

> > +               parameters_found = rzv2h_dsi_get_pll_parameters_values(dsi->info->cpg_dsi_limits,
> > +                                                                      &cpg_dsi_parameters,
> > +                                                                      mode_freq_millihz);
> > +               if (!parameters_found)
> > +                       continue;
> > +
> > +               hsfreq_millihz = DIV_ROUND_CLOSEST_ULL(cpg_dsi_parameters.freq_millihz * bpp,
> > +                                                      dsi->lanes);
> > +               parameters_found = rzv2h_dsi_get_pll_parameters_values(&rzv2h_plldsi_div_limits,
> > +                                                                      dsi_parameters,
> > +                                                                      hsfreq_millihz);
> > +               if (!parameters_found)
> > +                       continue;
> > +
> > +               if (abs(dsi_parameters->error_millihz) >= 500)
> > +                       continue;
> > +
> > +               hsfreq = DIV_ROUND_CLOSEST_ULL(hsfreq_millihz, MILLI);
> > +               if (hsfreq >= RZV2H_MIPI_DPHY_FOUT_MIN_IN_MEGA &&
> > +                   hsfreq <= RZV2H_MIPI_DPHY_FOUT_MAX_IN_MEGA) {
> > +                       dsi->mode_calc.mode_freq_hz = mode_freq_hz;
> > +                       dsi->mode_calc.mode_freq = mode_freq;
> > +                       return MODE_OK;
> > +               }
> > +       }
> > +
> > +       return MODE_CLOCK_RANGE;
> > +}
>
> > --- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi_regs.h
> > +++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi_regs.h
> > @@ -40,6 +40,39 @@
> >  #define DSIDPHYTIM3_THS_TRAIL(x)       ((x) << 8)
> >  #define DSIDPHYTIM3_THS_ZERO(x)                ((x) << 0)
> >
> > +/* RZ/V2H DPHY Registers */
> > +#define PLLENR                         0x000
> > +#define PLLENR_PLLEN                   BIT(0)
> > +
> > +#define PHYRSTR                                0x004
> > +#define PHYRSTR_PHYMRSTN               BIT(0)
> > +
> > +#define PLLCLKSET0R                    0x010
> > +#define PLLCLKSET0R_PLL_S(x)           ((x) << 0)
>
>  #define PLLCLKSET0R_PLL_S GENMASK(2, 0)
>
> and after that you can use FIELD_PREP(PLLCLKSET0R_PLL_S, x) in the code.
> More opportunities for masks below...
>
Thanks, I will make use of GENMASK/FIELD_PREP macros.

Cheers,
Prabhakar

^ permalink raw reply	[flat|nested] 18+ messages in thread

* Re: [PATCH v5 4/4] drm: renesas: rz-du: mipi_dsi: Add support for RZ/V2H(P) SoC
  2025-05-28  9:48     ` Lad, Prabhakar
@ 2025-05-28 12:31       ` Geert Uytterhoeven
  2025-05-28 17:43         ` Lad, Prabhakar
  0 siblings, 1 reply; 18+ messages in thread
From: Geert Uytterhoeven @ 2025-05-28 12:31 UTC (permalink / raw)
  To: Lad, Prabhakar
  Cc: Fabrizio Castro, Andrzej Hajda, Neil Armstrong, Robert Foss,
	Laurent Pinchart, Jonas Karlman, Jernej Skrabec, David Airlie,
	Simona Vetter, Maarten Lankhorst, Maxime Ripard,
	Thomas Zimmermann, Rob Herring, Krzysztof Kozlowski, Conor Dooley,
	Michael Turquette, Stephen Boyd, Biju Das, Magnus Damm, dri-devel,
	devicetree, linux-kernel, linux-renesas-soc, linux-clk,
	Lad Prabhakar

Hi Prabhakar,

On Wed, 28 May 2025 at 11:48, Lad, Prabhakar <prabhakar.csengg@gmail.com> wrote:
> On Fri, May 23, 2025 at 4:19 PM Geert Uytterhoeven <geert@linux-m68k.org> wrote:
> > On Mon, 12 May 2025 at 20:43, Prabhakar <prabhakar.csengg@gmail.com> wrote:
> > > From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> > >
> > > Add DSI support for Renesas RZ/V2H(P) SoC.
> > >
> > > Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> > > Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> > > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> >
> > Thanks for your patch!
> >
> > > --- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> > > +++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c

> > > @@ -47,6 +52,11 @@ struct rzg2l_mipi_dsi_hw_info {
> > >         u8 features;
> > >  };
> > >
> > > +struct rzv2h_dsi_mode_calc {
> > > +       unsigned long mode_freq;
> > > +       u64 mode_freq_hz;
> >
> > Interesting... I guess mode_freq is not in Hz?
> >
> Actually it is int Hz, I will make it unsigned long.

I really meant the first member.
As rzv2h_dphy_mode_clk_check() does "mode_freq_hz = mode_freq * MILLI",
mode_freq may be in kHz?

> > > +};

> > > @@ -308,6 +479,158 @@ static int rzg2l_dphy_conf_clks(struct rzg2l_mipi_dsi *dsi, unsigned long mode_f
> > >         return 0;
> > >  }
> > >
> > > +static unsigned int rzv2h_dphy_mode_clk_check(struct rzg2l_mipi_dsi *dsi,
> > > +                                             unsigned long mode_freq)
> > > +{
> > > +       struct rzv2h_plldsi_parameters *dsi_parameters = &dsi->dsi_parameters;
> > > +       u64 hsfreq_millihz, mode_freq_hz, mode_freq_millihz;
> > > +       struct rzv2h_plldsi_parameters cpg_dsi_parameters;
> > > +       unsigned int bpp, i;
> > > +
> > > +       bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
> > > +
> > > +       for (i = 0; i < 10; i += 1) {
> > > +               unsigned long hsfreq;
> > > +               bool parameters_found;
> > > +
> > > +               mode_freq_hz = mode_freq * MILLI + i;
> >
> > KILO?
> >
> OK, as mode_freq_hz is in Hz I'll make it unsigned long.

I am not sure if "unsigned long" is OK. Is mode_freq in kHz?
What is its largest value?

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

^ permalink raw reply	[flat|nested] 18+ messages in thread

* Re: [PATCH v5 1/4] clk: renesas: rzv2h-cpg: Add support for DSI clocks
  2025-05-28  7:09       ` Geert Uytterhoeven
@ 2025-05-28 14:13         ` Lad, Prabhakar
  0 siblings, 0 replies; 18+ messages in thread
From: Lad, Prabhakar @ 2025-05-28 14:13 UTC (permalink / raw)
  To: Geert Uytterhoeven
  Cc: Fabrizio Castro, Andrzej Hajda, Neil Armstrong, Robert Foss,
	Laurent Pinchart, Jonas Karlman, Jernej Skrabec, David Airlie,
	Simona Vetter, Maarten Lankhorst, Maxime Ripard,
	Thomas Zimmermann, Rob Herring, Krzysztof Kozlowski, Conor Dooley,
	Michael Turquette, Stephen Boyd, Biju Das, Magnus Damm, dri-devel,
	devicetree, linux-kernel, linux-renesas-soc, linux-clk,
	Lad Prabhakar

Hi Geert,

On Wed, May 28, 2025 at 8:09 AM Geert Uytterhoeven <geert@linux-m68k.org> wrote:
>
> Hi Prabhakar,
>
> On Tue, 27 May 2025 at 23:51, Lad, Prabhakar <prabhakar.csengg@gmail.com> wrote:
> > On Fri, May 23, 2025 at 3:45 PM Geert Uytterhoeven <geert@linux-m68k.org> wrote:
> > > On Mon, 12 May 2025 at 20:43, Prabhakar <prabhakar.csengg@gmail.com> wrote:
> > > > From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> > > >
> > > > Add support for PLLDSI and PLLDSI divider clocks.
> > > >
> > > > Introduce the `renesas-rzv2h-dsi.h` header to centralize and share
> > > > PLLDSI-related data structures, limits, and algorithms between the RZ/V2H
> > > > 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@renesas.com>
> > > > Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> > > > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
>
> > > > +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_plldsi_parameters *dsi_dividers = &priv->plldsi_div_parameters;
> > > > +       u64 rate_millihz;
> > > > +
> > > > +       /*
> > > > +        * Adjust the requested clock rate (`req->rate`) to ensure it falls within
> > > > +        * the supported range of 5.44 MHz to 187.5 MHz.
> > > > +        */
> > > > +       req->rate = clamp(req->rate, 5440000UL, 187500000UL);
> > > > +
> > > > +       rate_millihz = mul_u32_u32(req->rate, MILLI);
> > > > +       if (rate_millihz == dsi_dividers->error_millihz + dsi_dividers->freq_millihz)
> > > > +               goto exit_determine_rate;
> > > > +
> > > > +       if (!rzv2h_dsi_get_pll_parameters_values(priv->dsi_limits,
> > > > +                                                dsi_dividers, rate_millihz)) {
> > > > +               dev_err(priv->dev,
> > > > +                       "failed to determine rate for req->rate: %lu\n",
> > > > +                       req->rate);
> > > > +               return -EINVAL;
> > > > +       }
> > > > +
> > > > +exit_determine_rate:
> > > > +       req->best_parent_rate = req->rate * dsi_dividers->csdiv;
> > >
> > > Shouldn't this also update req->rate with the actual rate?
> > >
> > >     req->rate = DIV_ROUND_CLOSEST_ULL(dsi_dividers->freq_millihz, MILLI);
> > >
> > Agreed, I will update it.
>
> I think not updating req->rate may cause clk_get_rate() to return
> an incorrect value (can error_millihz > 1000?).  Any chance this fix
> can simplify the clock handling in the DSI driver?
>
Yes, error_millihz can be greater than 1000, as result the DSI driver
does check this (>= 500) and proceeds to try the next one.

Cheers,
Prabhaar

^ permalink raw reply	[flat|nested] 18+ messages in thread

* Re: [PATCH v5 4/4] drm: renesas: rz-du: mipi_dsi: Add support for RZ/V2H(P) SoC
  2025-05-28 12:31       ` Geert Uytterhoeven
@ 2025-05-28 17:43         ` Lad, Prabhakar
  0 siblings, 0 replies; 18+ messages in thread
From: Lad, Prabhakar @ 2025-05-28 17:43 UTC (permalink / raw)
  To: Geert Uytterhoeven
  Cc: Fabrizio Castro, Andrzej Hajda, Neil Armstrong, Robert Foss,
	Laurent Pinchart, Jonas Karlman, Jernej Skrabec, David Airlie,
	Simona Vetter, Maarten Lankhorst, Maxime Ripard,
	Thomas Zimmermann, Rob Herring, Krzysztof Kozlowski, Conor Dooley,
	Michael Turquette, Stephen Boyd, Biju Das, Magnus Damm, dri-devel,
	devicetree, linux-kernel, linux-renesas-soc, linux-clk,
	Lad Prabhakar

Hi Geert,

On Wed, May 28, 2025 at 1:32 PM Geert Uytterhoeven <geert@linux-m68k.org> wrote:
>
> Hi Prabhakar,
>
> On Wed, 28 May 2025 at 11:48, Lad, Prabhakar <prabhakar.csengg@gmail.com> wrote:
> > On Fri, May 23, 2025 at 4:19 PM Geert Uytterhoeven <geert@linux-m68k.org> wrote:
> > > On Mon, 12 May 2025 at 20:43, Prabhakar <prabhakar.csengg@gmail.com> wrote:
> > > > From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> > > >
> > > > Add DSI support for Renesas RZ/V2H(P) SoC.
> > > >
> > > > Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> > > > Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> > > > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> > >
> > > Thanks for your patch!
> > >
> > > > --- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> > > > +++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
>
> > > > @@ -47,6 +52,11 @@ struct rzg2l_mipi_dsi_hw_info {
> > > >         u8 features;
> > > >  };
> > > >
> > > > +struct rzv2h_dsi_mode_calc {
> > > > +       unsigned long mode_freq;
> > > > +       u64 mode_freq_hz;
> > >
> > > Interesting... I guess mode_freq is not in Hz?
> > >
> > Actually it is int Hz, I will make it unsigned long.
>
> I really meant the first member.
> As rzv2h_dphy_mode_clk_check() does "mode_freq_hz = mode_freq * MILLI",
> mode_freq may be in kHz?
>
Sorry, I got confused. mode_freq is in kHz probably I'll rename this
to make it clear.

> > > > +};
>
> > > > @@ -308,6 +479,158 @@ static int rzg2l_dphy_conf_clks(struct rzg2l_mipi_dsi *dsi, unsigned long mode_f
> > > >         return 0;
> > > >  }
> > > >
> > > > +static unsigned int rzv2h_dphy_mode_clk_check(struct rzg2l_mipi_dsi *dsi,
> > > > +                                             unsigned long mode_freq)
> > > > +{
> > > > +       struct rzv2h_plldsi_parameters *dsi_parameters = &dsi->dsi_parameters;
> > > > +       u64 hsfreq_millihz, mode_freq_hz, mode_freq_millihz;
> > > > +       struct rzv2h_plldsi_parameters cpg_dsi_parameters;
> > > > +       unsigned int bpp, i;
> > > > +
> > > > +       bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
> > > > +
> > > > +       for (i = 0; i < 10; i += 1) {
> > > > +               unsigned long hsfreq;
> > > > +               bool parameters_found;
> > > > +
> > > > +               mode_freq_hz = mode_freq * MILLI + i;
> > >
> > > KILO?
> > >
> > OK, as mode_freq_hz is in Hz I'll make it unsigned long.
>
> I am not sure if "unsigned long" is OK. Is mode_freq in kHz?
> What is its largest value?
>
Sorry I got confused, I will reinstate mode_freq_hz to be u64. The
largest value can depend on the max resolution by the display.

Cheers,
Prabhakar

^ permalink raw reply	[flat|nested] 18+ messages in thread

end of thread, other threads:[~2025-05-28 17:44 UTC | newest]

Thread overview: 18+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2025-05-12 18:42 [PATCH v5 0/4] Add support for DU/DSI clocks and DSI driver support for the Renesas RZ/V2H(P) SoC Prabhakar
2025-05-12 18:42 ` [PATCH v5 1/4] clk: renesas: rzv2h-cpg: Add support for DSI clocks Prabhakar
2025-05-20  6:19   ` Biju Das
2025-05-23 14:45   ` Geert Uytterhoeven
2025-05-27 21:50     ` Lad, Prabhakar
2025-05-28  7:09       ` Geert Uytterhoeven
2025-05-28 14:13         ` Lad, Prabhakar
2025-05-12 18:43 ` [PATCH v5 2/4] clk: renesas: r9a09g057: Add clock and reset entries for DSI and LCDC Prabhakar
2025-05-23 14:46   ` Geert Uytterhoeven
2025-05-27 22:01     ` Lad, Prabhakar
2025-05-12 18:43 ` [PATCH v5 3/4] dt-bindings: display: bridge: renesas, dsi: Add support for RZ/V2H(P) SoC Prabhakar
2025-05-23 14:58   ` [PATCH v5 3/4] dt-bindings: display: bridge: renesas,dsi: " Geert Uytterhoeven
2025-05-27 22:04     ` Lad, Prabhakar
2025-05-12 18:43 ` [PATCH v5 4/4] drm: renesas: rz-du: mipi_dsi: " Prabhakar
2025-05-23 15:18   ` Geert Uytterhoeven
2025-05-28  9:48     ` Lad, Prabhakar
2025-05-28 12:31       ` Geert Uytterhoeven
2025-05-28 17:43         ` Lad, Prabhakar

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