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Release 4.17 drivers/gpu/drm/sun4i/sun4i_hdmi_tmds_clk.c

/*
 * Copyright (C) 2016 Free Electrons
 * Copyright (C) 2016 NextThing Co
 *
 * Maxime Ripard <maxime.ripard@free-electrons.com>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of
 * the License, or (at your option) any later version.
 */

#include <linux/clk-provider.h>

#include "sun4i_hdmi.h"


struct sun4i_tmds {
	
struct clk_hw		hw;
	
struct sun4i_hdmi	*hdmi;

	
u8			div_offset;
};


static inline struct sun4i_tmds *hw_to_tmds(struct clk_hw *hw) { return container_of(hw, struct sun4i_tmds, hw); }

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Maxime Ripard25100.00%1100.00%
Total25100.00%1100.00%


static unsigned long sun4i_tmds_calc_divider(unsigned long rate, unsigned long parent_rate, u8 div_offset, u8 *div, bool *half) { unsigned long best_rate = 0; u8 best_m = 0, m; bool is_double; for (m = div_offset ?: 1; m < (16 + div_offset); m++) { u8 d; for (d = 1; d < 3; d++) { unsigned long tmp_rate; tmp_rate = parent_rate / m / d; if (tmp_rate > rate) continue; if (!best_rate || (rate - tmp_rate) < (rate - best_rate)) { best_rate = tmp_rate; best_m = m; is_double = d; } } } if (div && half) { *div = best_m; *half = is_double; } return best_rate; }

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PersonTokensPropCommitsCommitProp
Maxime Ripard14393.46%150.00%
Chen-Yu Tsai106.54%150.00%
Total153100.00%2100.00%


static int sun4i_tmds_determine_rate(struct clk_hw *hw, struct clk_rate_request *req) { struct sun4i_tmds *tmds = hw_to_tmds(hw); struct clk_hw *parent = NULL; unsigned long best_parent = 0; unsigned long rate = req->rate; int best_div = 1, best_half = 1; int i, j, p; /* * We only consider PLL3, since the TCON is very likely to be * clocked from it, and to have the same rate than our HDMI * clock, so we should not need to do anything. */ for (p = 0; p < clk_hw_get_num_parents(hw); p++) { parent = clk_hw_get_parent_by_index(hw, p); if (!parent) continue; for (i = 1; i < 3; i++) { for (j = tmds->div_offset ?: 1; j < (16 + tmds->div_offset); j++) { unsigned long ideal = rate * i * j; unsigned long rounded; rounded = clk_hw_round_rate(parent, ideal); if (rounded == ideal) { best_parent = rounded; best_half = i; best_div = j; goto out; } if (!best_parent || abs(rate - rounded / i / j) < abs(rate - best_parent / best_half / best_div)) { best_parent = rounded; best_half = i; best_div = j; } } } } if (!parent) return -EINVAL; out: req->rate = best_parent / best_half / best_div; req->best_parent_rate = best_parent; req->best_parent_hw = parent; return 0; }

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PersonTokensPropCommitsCommitProp
Maxime Ripard19574.71%116.67%
Chen-Yu Tsai5420.69%233.33%
Jonathan Liu124.60%350.00%
Total261100.00%6100.00%


static unsigned long sun4i_tmds_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) { struct sun4i_tmds *tmds = hw_to_tmds(hw); u32 reg; reg = readl(tmds->hdmi->base + SUN4I_HDMI_PAD_CTRL1_REG); if (reg & SUN4I_HDMI_PAD_CTRL1_HALVE_CLK) parent_rate /= 2; reg = readl(tmds->hdmi->base + SUN4I_HDMI_PLL_CTRL_REG); reg = ((reg >> 4) & 0xf) + tmds->div_offset; if (!reg) reg = 1; return parent_rate / reg; }

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Maxime Ripard8993.68%150.00%
Chen-Yu Tsai66.32%150.00%
Total95100.00%2100.00%


static int sun4i_tmds_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long parent_rate) { struct sun4i_tmds *tmds = hw_to_tmds(hw); bool half; u32 reg; u8 div; sun4i_tmds_calc_divider(rate, parent_rate, tmds->div_offset, &div, &half); reg = readl(tmds->hdmi->base + SUN4I_HDMI_PAD_CTRL1_REG); reg &= ~SUN4I_HDMI_PAD_CTRL1_HALVE_CLK; if (half) reg |= SUN4I_HDMI_PAD_CTRL1_HALVE_CLK; writel(reg, tmds->hdmi->base + SUN4I_HDMI_PAD_CTRL1_REG); reg = readl(tmds->hdmi->base + SUN4I_HDMI_PLL_CTRL_REG); reg &= ~SUN4I_HDMI_PLL_CTRL_DIV_MASK; writel(reg | SUN4I_HDMI_PLL_CTRL_DIV(div - tmds->div_offset), tmds->hdmi->base + SUN4I_HDMI_PLL_CTRL_REG); return 0; }

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Maxime Ripard12994.16%150.00%
Chen-Yu Tsai85.84%150.00%
Total137100.00%2100.00%


static u8 sun4i_tmds_get_parent(struct clk_hw *hw) { struct sun4i_tmds *tmds = hw_to_tmds(hw); u32 reg; reg = readl(tmds->hdmi->base + SUN4I_HDMI_PLL_DBG0_REG); return ((reg & SUN4I_HDMI_PLL_DBG0_TMDS_PARENT_MASK) >> SUN4I_HDMI_PLL_DBG0_TMDS_PARENT_SHIFT); }

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Maxime Ripard48100.00%1100.00%
Total48100.00%1100.00%


static int sun4i_tmds_set_parent(struct clk_hw *hw, u8 index) { struct sun4i_tmds *tmds = hw_to_tmds(hw); u32 reg; if (index > 1) return -EINVAL; reg = readl(tmds->hdmi->base + SUN4I_HDMI_PLL_DBG0_REG); reg &= ~SUN4I_HDMI_PLL_DBG0_TMDS_PARENT_MASK; writel(reg | SUN4I_HDMI_PLL_DBG0_TMDS_PARENT(index), tmds->hdmi->base + SUN4I_HDMI_PLL_DBG0_REG); return 0; }

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Maxime Ripard76100.00%1100.00%
Total76100.00%1100.00%

static const struct clk_ops sun4i_tmds_ops = { .determine_rate = sun4i_tmds_determine_rate, .recalc_rate = sun4i_tmds_recalc_rate, .set_rate = sun4i_tmds_set_rate, .get_parent = sun4i_tmds_get_parent, .set_parent = sun4i_tmds_set_parent, };
int sun4i_tmds_create(struct sun4i_hdmi *hdmi) { struct clk_init_data init; struct sun4i_tmds *tmds; const char *parents[2]; parents[0] = __clk_get_name(hdmi->pll0_clk); if (!parents[0]) return -ENODEV; parents[1] = __clk_get_name(hdmi->pll1_clk); if (!parents[1]) return -ENODEV; tmds = devm_kzalloc(hdmi->dev, sizeof(*tmds), GFP_KERNEL); if (!tmds) return -ENOMEM; init.name = "hdmi-tmds"; init.ops = &sun4i_tmds_ops; init.parent_names = parents; init.num_parents = 2; init.flags = CLK_SET_RATE_PARENT; tmds->hdmi = hdmi; tmds->hw.init = &init; tmds->div_offset = hdmi->variant->tmds_clk_div_offset; hdmi->tmds_clk = devm_clk_register(hdmi->dev, &tmds->hw); if (IS_ERR(hdmi->tmds_clk)) return PTR_ERR(hdmi->tmds_clk); return 0; }

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PersonTokensPropCommitsCommitProp
Maxime Ripard18394.82%150.00%
Chen-Yu Tsai105.18%150.00%
Total193100.00%2100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
Maxime Ripard94290.14%116.67%
Chen-Yu Tsai918.71%233.33%
Jonathan Liu121.15%350.00%
Total1045100.00%6100.00%
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