[PATCH v4 01/20] clk: renesas: rzv2h: Add PLLDSI clk mux support
From: Tommaso Merciai <tommaso.merciai.xr@bp.renesas.com>
Date: 2026-02-02 11:58:46
Also in:
dri-devel, linux-clk, linux-renesas-soc, lkml
Subsystem:
common clk framework, renesas clock drivers, the rest · Maintainers:
Michael Turquette, Stephen Boyd, Geert Uytterhoeven, Linus Torvalds
Add PLLDSI clk mux support to select PLLDSI clock from different clock
sources.
Introduce the DEF_PLLDSI_SMUX() macro to define these muxes and register
them in the clock driver.
Extend the determine_rate callback to calculate and propagate PLL
parameters via rzv2h_get_pll_dtable_pars() when LVDS output is selected,
using a new helper function rzv2h_cpg_plldsi_smux_lvds_determine_rate().
The CLK_SMUX2_DSI{0,1}_CLK clock multiplexers select between two paths
with different duty cycles:
- CDIV7_DSIx_CLK (LVDS path, parent index 0): asymmetric H/L=4/3 duty (4/7)
- CSDIV_DSIx (DSI/RGB path, parent index 1): symmetric 50% duty (1/2)
Implement rzv2h_cpg_plldsi_smux_{get,set}_duty_cycle clock operations to
allow the DRM driver to query and configure the appropriate clock path
based on the required output duty cycle.
Signed-off-by: Tommaso Merciai <tommaso.merciai.xr@bp.renesas.com>
---
v1->v2:
- Added rzv2h_cpg_plldsi_smux_{get,set}_duty_cycle clock operations to
allow the DRM driver to query and configure the appropriate clock path
based on the required output duty cycle.
- Updated commit message accordingly.
v2->v3:
- Added missing defines for duty num/den
v3->v4:
- Fixed build error using temporary variable mask
into rzv2h_cpg_plldsi_smux_clk_register().
drivers/clk/renesas/rzv2h-cpg.c | 184 ++++++++++++++++++++++++++++++++
drivers/clk/renesas/rzv2h-cpg.h | 8 ++
2 files changed, 192 insertions(+)
diff --git a/drivers/clk/renesas/rzv2h-cpg.c b/drivers/clk/renesas/rzv2h-cpg.c
index f6c47fb89bca..4a245dfff27c 100644
--- a/drivers/clk/renesas/rzv2h-cpg.c
+++ b/drivers/clk/renesas/rzv2h-cpg.c@@ -76,6 +76,11 @@ /* On RZ/G3E SoC we have two DSI PLLs */ #define MAX_CPG_DSI_PLL 2 +#define CPG_PLLDSI_SMUX_LVDS_DUTY_NUM 4 +#define CPG_PLLDSI_SMUX_LVDS_DUTY_DEN 7 +#define CPG_PLLDSI_SMUX_DSI_RGB_DUTY_NUM 1 +#define CPG_PLLDSI_SMUX_DSI_RGB_DUTY_DEN 2 + /** * struct rzv2h_pll_dsi_info - PLL DSI information, holds the limits and parameters *
@@ -418,6 +423,20 @@ bool rzv2h_get_pll_divs_pars(const struct rzv2h_pll_limits *limits, } EXPORT_SYMBOL_NS_GPL(rzv2h_get_pll_divs_pars, "RZV2H_CPG"); +/** + * struct rzv2h_plldsi_mux_clk - PLL DSI MUX clock + * + * @priv: CPG private data + * @mux: mux clk + */ +struct rzv2h_plldsi_mux_clk { + struct rzv2h_cpg_priv *priv; + struct clk_mux mux; +}; + +#define to_plldsi_clk_mux(_mux) \ + container_of(_mux, struct rzv2h_plldsi_mux_clk, mux) + static unsigned long rzv2h_cpg_plldsi_div_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) {
@@ -649,6 +668,168 @@ static int rzv2h_cpg_plldsi_set_rate(struct clk_hw *hw, unsigned long rate, return rzv2h_cpg_pll_set_rate(pll_clk, &dsi_info->pll_dsi_parameters.pll, true); } +static u8 rzv2h_cpg_plldsi_smux_get_parent(struct clk_hw *hw) +{ + return clk_mux_ops.get_parent(hw); +} + +static int rzv2h_cpg_plldsi_smux_set_parent(struct clk_hw *hw, u8 index) +{ + return clk_mux_ops.set_parent(hw, index); +} + +static int rzv2h_cpg_plldsi_smux_lvds_determine_rate(struct rzv2h_cpg_priv *priv, + struct pll_clk *pll_clk, + struct clk_rate_request *req) +{ + struct rzv2h_pll_div_pars *dsi_params; + struct rzv2h_pll_dsi_info *dsi_info; + u8 lvds_table[] = { 7 }; + u64 rate_millihz; + + dsi_info = &priv->pll_dsi_info[pll_clk->pll.instance]; + dsi_params = &dsi_info->pll_dsi_parameters; + + rate_millihz = mul_u32_u32(req->rate, MILLI); + if (!rzv2h_get_pll_divs_pars(dsi_info->pll_dsi_limits, dsi_params, + lvds_table, ARRAY_SIZE(lvds_table), rate_millihz)) { + dev_err(priv->dev, "failed to determine rate for req->rate: %lu\n", + req->rate); + return -EINVAL; + } + + req->rate = DIV_ROUND_CLOSEST_ULL(dsi_params->div.freq_millihz, MILLI); + req->best_parent_rate = req->rate; + dsi_info->req_pll_dsi_rate = req->best_parent_rate * dsi_params->div.divider_value; + + return 0; +} + +static int rzv2h_cpg_plldsi_smux_determine_rate(struct clk_hw *hw, + struct clk_rate_request *req) +{ + struct clk_mux *mux = to_clk_mux(hw); + struct rzv2h_plldsi_mux_clk *dsi_mux = to_plldsi_clk_mux(mux); + struct pll_clk *pll_clk = to_pll(clk_hw_get_parent(hw)); + struct rzv2h_cpg_priv *priv = dsi_mux->priv; + + /* + * For LVDS output (parent index 0), calculate PLL parameters with + * fixed divider value of 7. For DSI/RGB output (parent index 1) skip + * PLL calculation here as it's handled by determine_rate of the + * divider (up one level). + */ + if (!clk_mux_ops.get_parent(hw)) + return rzv2h_cpg_plldsi_smux_lvds_determine_rate(priv, pll_clk, req); + + req->best_parent_rate = req->rate; + return 0; +} + +static int rzv2h_cpg_plldsi_smux_get_duty_cycle(struct clk_hw *hw, + struct clk_duty *duty) +{ + u8 parent = clk_mux_ops.get_parent(hw); + + /* + * CDIV7_DSIx_CLK - LVDS path (div7) - duty 4/7. + * CSDIV_DSIx - DSI/RGB path (csdiv) - duty 1/2. + */ + if (parent == 0) { + duty->num = CPG_PLLDSI_SMUX_LVDS_DUTY_NUM; + duty->den = CPG_PLLDSI_SMUX_LVDS_DUTY_DEN; + } else { + duty->num = CPG_PLLDSI_SMUX_DSI_RGB_DUTY_NUM; + duty->den = CPG_PLLDSI_SMUX_DSI_RGB_DUTY_DEN; + } + + return 0; +} + +static int rzv2h_cpg_plldsi_smux_set_duty_cycle(struct clk_hw *hw, + struct clk_duty *duty) +{ + struct clk_hw *parent_hw; + u8 parent_idx; + + /* + * Select parent based on requested duty cycle: + * - If duty > 50% (num/den > 1/2), select LVDS path (parent 0) + * - Otherwise, select DSI/RGB path (parent 1) + */ + if (duty->num * CPG_PLLDSI_SMUX_DSI_RGB_DUTY_DEN > + duty->den * CPG_PLLDSI_SMUX_DSI_RGB_DUTY_NUM) + parent_idx = 0; + else + parent_idx = 1; + + if (parent_idx >= clk_hw_get_num_parents(hw)) + return -EINVAL; + + parent_hw = clk_hw_get_parent_by_index(hw, parent_idx); + if (!parent_hw) + return -EINVAL; + + return clk_hw_set_parent(hw, parent_hw); +} + +static const struct clk_ops rzv2h_cpg_plldsi_smux_ops = { + .determine_rate = rzv2h_cpg_plldsi_smux_determine_rate, + .get_parent = rzv2h_cpg_plldsi_smux_get_parent, + .set_parent = rzv2h_cpg_plldsi_smux_set_parent, + .get_duty_cycle = rzv2h_cpg_plldsi_smux_get_duty_cycle, + .set_duty_cycle = rzv2h_cpg_plldsi_smux_set_duty_cycle, +}; + +static struct clk * __init +rzv2h_cpg_plldsi_smux_clk_register(const struct cpg_core_clk *core, + struct rzv2h_cpg_priv *priv) +{ + struct rzv2h_plldsi_mux_clk *clk_hw_data; + struct clk_init_data init; + struct clk_hw *clk_hw; + struct smuxed smux; + u8 width, mask; + int ret; + + smux = core->cfg.smux; + mask = smux.width; + width = fls(mask) - ffs(mask) + 1; + + if (width + smux.width > 16) { + dev_err(priv->dev, "mux value exceeds LOWORD field\n"); + return ERR_PTR(-EINVAL); + } + + 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; + + init.name = core->name; + init.ops = &rzv2h_cpg_plldsi_smux_ops; + init.flags = core->flag; + init.parent_names = core->parent_names; + init.num_parents = core->num_parents; + + clk_hw_data->mux.reg = priv->base + smux.offset; + + clk_hw_data->mux.shift = smux.shift; + clk_hw_data->mux.mask = smux.width; + clk_hw_data->mux.flags = core->mux_flags; + clk_hw_data->mux.lock = &priv->rmw_lock; + + clk_hw = &clk_hw_data->mux.hw; + clk_hw->init = &init; + + ret = devm_clk_hw_register(priv->dev, clk_hw); + if (ret) + return ERR_PTR(ret); + + return clk_hw->clk; +} + static int rzv2h_cpg_pll_clk_is_enabled(struct clk_hw *hw) { struct pll_clk *pll_clk = to_pll(hw);
@@ -1085,6 +1266,9 @@ rzv2h_cpg_register_core_clk(const struct cpg_core_clk *core, case CLK_TYPE_PLLDSI_DIV: clk = rzv2h_cpg_plldsi_div_clk_register(core, priv); break; + case CLK_TYPE_PLLDSI_SMUX: + clk = rzv2h_cpg_plldsi_smux_clk_register(core, priv); + break; default: goto fail; }
diff --git a/drivers/clk/renesas/rzv2h-cpg.h b/drivers/clk/renesas/rzv2h-cpg.h
index dc957bdaf5e9..74a3824d605e 100644
--- a/drivers/clk/renesas/rzv2h-cpg.h
+++ b/drivers/clk/renesas/rzv2h-cpg.h@@ -203,6 +203,7 @@ enum clk_types { CLK_TYPE_SMUX, /* Static Mux */ CLK_TYPE_PLLDSI, /* PLLDSI */ CLK_TYPE_PLLDSI_DIV, /* PLLDSI divider */ + CLK_TYPE_PLLDSI_SMUX, /* PLLDSI Static Mux */ }; #define DEF_TYPE(_name, _id, _type...) \
@@ -241,6 +242,13 @@ enum clk_types { .dtable = _dtable, \ .parent = _parent, \ .flag = CLK_SET_RATE_PARENT) +#define DEF_PLLDSI_SMUX(_name, _id, _smux_packed, _parent_names) \ + DEF_TYPE(_name, _id, CLK_TYPE_PLLDSI_SMUX, \ + .cfg.smux = _smux_packed, \ + .parent_names = _parent_names, \ + .num_parents = ARRAY_SIZE(_parent_names), \ + .flag = CLK_SET_RATE_PARENT, \ + .mux_flags = CLK_MUX_HIWORD_MASK) /** * struct rzv2h_mod_clk - Module Clocks definitions
--
2.43.0