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159 lines
3.5 KiB
159 lines
3.5 KiB
// SPDX-License-Identifier: GPL-2.0-or-later |
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/* |
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* Copyright (C) 2016 Maxime Ripard |
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* Maxime Ripard <[email protected]> |
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*/ |
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#include <linux/clk-provider.h> |
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#include <linux/io.h> |
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#include "ccu_gate.h" |
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#include "ccu_nk.h" |
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struct _ccu_nk { |
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unsigned long n, min_n, max_n; |
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unsigned long k, min_k, max_k; |
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}; |
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static void ccu_nk_find_best(unsigned long parent, unsigned long rate, |
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struct _ccu_nk *nk) |
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{ |
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unsigned long best_rate = 0; |
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unsigned int best_k = 0, best_n = 0; |
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unsigned int _k, _n; |
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for (_k = nk->min_k; _k <= nk->max_k; _k++) { |
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for (_n = nk->min_n; _n <= nk->max_n; _n++) { |
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unsigned long tmp_rate = parent * _n * _k; |
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if (tmp_rate > rate) |
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continue; |
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if ((rate - tmp_rate) < (rate - best_rate)) { |
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best_rate = tmp_rate; |
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best_k = _k; |
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best_n = _n; |
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} |
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} |
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} |
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nk->k = best_k; |
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nk->n = best_n; |
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} |
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static void ccu_nk_disable(struct clk_hw *hw) |
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{ |
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struct ccu_nk *nk = hw_to_ccu_nk(hw); |
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return ccu_gate_helper_disable(&nk->common, nk->enable); |
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} |
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static int ccu_nk_enable(struct clk_hw *hw) |
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{ |
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struct ccu_nk *nk = hw_to_ccu_nk(hw); |
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return ccu_gate_helper_enable(&nk->common, nk->enable); |
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} |
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static int ccu_nk_is_enabled(struct clk_hw *hw) |
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{ |
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struct ccu_nk *nk = hw_to_ccu_nk(hw); |
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return ccu_gate_helper_is_enabled(&nk->common, nk->enable); |
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} |
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static unsigned long ccu_nk_recalc_rate(struct clk_hw *hw, |
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unsigned long parent_rate) |
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{ |
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struct ccu_nk *nk = hw_to_ccu_nk(hw); |
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unsigned long rate, n, k; |
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u32 reg; |
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reg = readl(nk->common.base + nk->common.reg); |
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n = reg >> nk->n.shift; |
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n &= (1 << nk->n.width) - 1; |
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n += nk->n.offset; |
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if (!n) |
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n++; |
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k = reg >> nk->k.shift; |
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k &= (1 << nk->k.width) - 1; |
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k += nk->k.offset; |
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if (!k) |
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k++; |
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rate = parent_rate * n * k; |
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if (nk->common.features & CCU_FEATURE_FIXED_POSTDIV) |
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rate /= nk->fixed_post_div; |
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return rate; |
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} |
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static long ccu_nk_round_rate(struct clk_hw *hw, unsigned long rate, |
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unsigned long *parent_rate) |
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{ |
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struct ccu_nk *nk = hw_to_ccu_nk(hw); |
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struct _ccu_nk _nk; |
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if (nk->common.features & CCU_FEATURE_FIXED_POSTDIV) |
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rate *= nk->fixed_post_div; |
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_nk.min_n = nk->n.min ?: 1; |
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_nk.max_n = nk->n.max ?: 1 << nk->n.width; |
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_nk.min_k = nk->k.min ?: 1; |
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_nk.max_k = nk->k.max ?: 1 << nk->k.width; |
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ccu_nk_find_best(*parent_rate, rate, &_nk); |
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rate = *parent_rate * _nk.n * _nk.k; |
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if (nk->common.features & CCU_FEATURE_FIXED_POSTDIV) |
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rate = rate / nk->fixed_post_div; |
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return rate; |
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} |
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static int ccu_nk_set_rate(struct clk_hw *hw, unsigned long rate, |
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unsigned long parent_rate) |
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{ |
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struct ccu_nk *nk = hw_to_ccu_nk(hw); |
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unsigned long flags; |
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struct _ccu_nk _nk; |
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u32 reg; |
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if (nk->common.features & CCU_FEATURE_FIXED_POSTDIV) |
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rate = rate * nk->fixed_post_div; |
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_nk.min_n = nk->n.min ?: 1; |
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_nk.max_n = nk->n.max ?: 1 << nk->n.width; |
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_nk.min_k = nk->k.min ?: 1; |
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_nk.max_k = nk->k.max ?: 1 << nk->k.width; |
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ccu_nk_find_best(parent_rate, rate, &_nk); |
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spin_lock_irqsave(nk->common.lock, flags); |
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reg = readl(nk->common.base + nk->common.reg); |
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reg &= ~GENMASK(nk->n.width + nk->n.shift - 1, nk->n.shift); |
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reg &= ~GENMASK(nk->k.width + nk->k.shift - 1, nk->k.shift); |
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reg |= (_nk.k - nk->k.offset) << nk->k.shift; |
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reg |= (_nk.n - nk->n.offset) << nk->n.shift; |
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writel(reg, nk->common.base + nk->common.reg); |
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spin_unlock_irqrestore(nk->common.lock, flags); |
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ccu_helper_wait_for_lock(&nk->common, nk->lock); |
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return 0; |
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} |
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const struct clk_ops ccu_nk_ops = { |
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.disable = ccu_nk_disable, |
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.enable = ccu_nk_enable, |
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.is_enabled = ccu_nk_is_enabled, |
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.recalc_rate = ccu_nk_recalc_rate, |
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.round_rate = ccu_nk_round_rate, |
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.set_rate = ccu_nk_set_rate, |
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};
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