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![Claudiu Beznea](/assets/img/avatar_default.png)
Commitfacb87ad75
("clk: at91: sama7g5: remove prescaler part of master clock") removed the master clock's prescaler from clock tree of SAMA7G5 as it has been discovered that there is a hardware bug when trying to change it at run-time (bug is described in description of commitfacb87ad75
("clk: at91: sama7g5: remove prescaler part of master clock")). This was previously changed at CPUFreq driver request. Thus, with commitfacb87ad75
("clk: at91: sama7g5: remove prescaler part of master clock") there is no need of code that handles run-time changes of master clock's prescaler, thus remove this code. Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com> Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com> Link: https://lore.kernel.org/r/20220203110202.18329-1-claudiu.beznea@microchip.com
869 lines
22 KiB
C
869 lines
22 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
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/*
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* Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.com>
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*/
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#include <linux/clk-provider.h>
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#include <linux/clkdev.h>
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#include <linux/clk.h>
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#include <linux/clk/at91_pmc.h>
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#include <linux/of.h>
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#include <linux/mfd/syscon.h>
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#include <linux/regmap.h>
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#include "pmc.h"
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#define MASTER_PRES_MASK 0x7
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#define MASTER_PRES_MAX MASTER_PRES_MASK
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#define MASTER_DIV_SHIFT 8
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#define MASTER_DIV_MASK 0x7
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#define PMC_MCR_CSS_SHIFT (16)
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#define MASTER_MAX_ID 4
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#define to_clk_master(hw) container_of(hw, struct clk_master, hw)
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struct clk_master {
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struct clk_hw hw;
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struct regmap *regmap;
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spinlock_t *lock;
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const struct clk_master_layout *layout;
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const struct clk_master_characteristics *characteristics;
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struct at91_clk_pms pms;
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u32 *mux_table;
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u32 mckr;
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int chg_pid;
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u8 id;
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u8 parent;
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u8 div;
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u32 safe_div;
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};
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/* MCK div reference to be used by notifier. */
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static struct clk_master *master_div;
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static inline bool clk_master_ready(struct clk_master *master)
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{
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unsigned int bit = master->id ? AT91_PMC_MCKXRDY : AT91_PMC_MCKRDY;
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unsigned int status;
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regmap_read(master->regmap, AT91_PMC_SR, &status);
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return !!(status & bit);
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}
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static int clk_master_prepare(struct clk_hw *hw)
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{
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struct clk_master *master = to_clk_master(hw);
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unsigned long flags;
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spin_lock_irqsave(master->lock, flags);
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while (!clk_master_ready(master))
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cpu_relax();
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spin_unlock_irqrestore(master->lock, flags);
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return 0;
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}
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static int clk_master_is_prepared(struct clk_hw *hw)
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{
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struct clk_master *master = to_clk_master(hw);
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unsigned long flags;
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bool status;
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spin_lock_irqsave(master->lock, flags);
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status = clk_master_ready(master);
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spin_unlock_irqrestore(master->lock, flags);
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return status;
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}
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static unsigned long clk_master_div_recalc_rate(struct clk_hw *hw,
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unsigned long parent_rate)
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{
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u8 div;
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unsigned long flags, rate = parent_rate;
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struct clk_master *master = to_clk_master(hw);
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const struct clk_master_layout *layout = master->layout;
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const struct clk_master_characteristics *characteristics =
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master->characteristics;
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unsigned int mckr;
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spin_lock_irqsave(master->lock, flags);
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regmap_read(master->regmap, master->layout->offset, &mckr);
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spin_unlock_irqrestore(master->lock, flags);
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mckr &= layout->mask;
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div = (mckr >> MASTER_DIV_SHIFT) & MASTER_DIV_MASK;
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rate /= characteristics->divisors[div];
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if (rate < characteristics->output.min)
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pr_warn("master clk div is underclocked");
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else if (rate > characteristics->output.max)
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pr_warn("master clk div is overclocked");
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return rate;
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}
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static int clk_master_div_save_context(struct clk_hw *hw)
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{
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struct clk_master *master = to_clk_master(hw);
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struct clk_hw *parent_hw = clk_hw_get_parent(hw);
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unsigned long flags;
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unsigned int mckr, div;
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spin_lock_irqsave(master->lock, flags);
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regmap_read(master->regmap, master->layout->offset, &mckr);
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spin_unlock_irqrestore(master->lock, flags);
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mckr &= master->layout->mask;
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div = (mckr >> MASTER_DIV_SHIFT) & MASTER_DIV_MASK;
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div = master->characteristics->divisors[div];
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master->pms.parent_rate = clk_hw_get_rate(parent_hw);
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master->pms.rate = DIV_ROUND_CLOSEST(master->pms.parent_rate, div);
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return 0;
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}
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static void clk_master_div_restore_context(struct clk_hw *hw)
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{
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struct clk_master *master = to_clk_master(hw);
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unsigned long flags;
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unsigned int mckr;
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u8 div;
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spin_lock_irqsave(master->lock, flags);
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regmap_read(master->regmap, master->layout->offset, &mckr);
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spin_unlock_irqrestore(master->lock, flags);
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mckr &= master->layout->mask;
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div = (mckr >> MASTER_DIV_SHIFT) & MASTER_DIV_MASK;
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div = master->characteristics->divisors[div];
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if (div != DIV_ROUND_CLOSEST(master->pms.parent_rate, master->pms.rate))
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pr_warn("MCKR DIV not configured properly by firmware!\n");
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}
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static const struct clk_ops master_div_ops = {
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.prepare = clk_master_prepare,
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.is_prepared = clk_master_is_prepared,
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.recalc_rate = clk_master_div_recalc_rate,
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.save_context = clk_master_div_save_context,
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.restore_context = clk_master_div_restore_context,
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};
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/* This function must be called with lock acquired. */
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static int clk_master_div_set(struct clk_master *master,
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unsigned long parent_rate, int div)
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{
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const struct clk_master_characteristics *characteristics =
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master->characteristics;
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unsigned long rate = parent_rate;
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unsigned int max_div = 0, div_index = 0, max_div_index = 0;
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unsigned int i, mckr, tmp;
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int ret;
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for (i = 0; i < ARRAY_SIZE(characteristics->divisors); i++) {
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if (!characteristics->divisors[i])
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break;
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if (div == characteristics->divisors[i])
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div_index = i;
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if (max_div < characteristics->divisors[i]) {
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max_div = characteristics->divisors[i];
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max_div_index = i;
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}
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}
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if (div > max_div)
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div_index = max_div_index;
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ret = regmap_read(master->regmap, master->layout->offset, &mckr);
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if (ret)
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return ret;
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mckr &= master->layout->mask;
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tmp = (mckr >> MASTER_DIV_SHIFT) & MASTER_DIV_MASK;
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if (tmp == div_index)
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return 0;
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rate /= characteristics->divisors[div_index];
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if (rate < characteristics->output.min)
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pr_warn("master clk div is underclocked");
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else if (rate > characteristics->output.max)
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pr_warn("master clk div is overclocked");
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mckr &= ~(MASTER_DIV_MASK << MASTER_DIV_SHIFT);
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mckr |= (div_index << MASTER_DIV_SHIFT);
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ret = regmap_write(master->regmap, master->layout->offset, mckr);
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if (ret)
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return ret;
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while (!clk_master_ready(master))
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cpu_relax();
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master->div = characteristics->divisors[div_index];
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return 0;
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}
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static unsigned long clk_master_div_recalc_rate_chg(struct clk_hw *hw,
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unsigned long parent_rate)
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{
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struct clk_master *master = to_clk_master(hw);
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return DIV_ROUND_CLOSEST_ULL(parent_rate, master->div);
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}
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static void clk_master_div_restore_context_chg(struct clk_hw *hw)
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{
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struct clk_master *master = to_clk_master(hw);
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unsigned long flags;
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int ret;
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spin_lock_irqsave(master->lock, flags);
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ret = clk_master_div_set(master, master->pms.parent_rate,
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DIV_ROUND_CLOSEST(master->pms.parent_rate,
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master->pms.rate));
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spin_unlock_irqrestore(master->lock, flags);
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if (ret)
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pr_warn("Failed to restore MCK DIV clock\n");
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}
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static const struct clk_ops master_div_ops_chg = {
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.prepare = clk_master_prepare,
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.is_prepared = clk_master_is_prepared,
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.recalc_rate = clk_master_div_recalc_rate_chg,
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.save_context = clk_master_div_save_context,
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.restore_context = clk_master_div_restore_context_chg,
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};
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static int clk_master_div_notifier_fn(struct notifier_block *notifier,
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unsigned long code, void *data)
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{
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const struct clk_master_characteristics *characteristics =
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master_div->characteristics;
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struct clk_notifier_data *cnd = data;
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unsigned long flags, new_parent_rate, new_rate;
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unsigned int mckr, div, new_div = 0;
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int ret, i;
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long tmp_diff;
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long best_diff = -1;
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spin_lock_irqsave(master_div->lock, flags);
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switch (code) {
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case PRE_RATE_CHANGE:
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/*
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* We want to avoid any overclocking of MCK DIV domain. To do
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* this we set a safe divider (the underclocking is not of
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* interest as we can go as low as 32KHz). The relation
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* b/w this clock and its parents are as follows:
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*
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* FRAC PLL -> DIV PLL -> MCK DIV
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*
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* With the proper safe divider we should be good even with FRAC
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* PLL at its maximum value.
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*/
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ret = regmap_read(master_div->regmap, master_div->layout->offset,
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&mckr);
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if (ret) {
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ret = NOTIFY_STOP_MASK;
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goto unlock;
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}
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mckr &= master_div->layout->mask;
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div = (mckr >> MASTER_DIV_SHIFT) & MASTER_DIV_MASK;
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/* Switch to safe divider. */
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clk_master_div_set(master_div,
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cnd->old_rate * characteristics->divisors[div],
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master_div->safe_div);
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break;
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case POST_RATE_CHANGE:
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/*
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* At this point we want to restore MCK DIV domain to its maximum
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* allowed rate.
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*/
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ret = regmap_read(master_div->regmap, master_div->layout->offset,
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&mckr);
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if (ret) {
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ret = NOTIFY_STOP_MASK;
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goto unlock;
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}
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mckr &= master_div->layout->mask;
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div = (mckr >> MASTER_DIV_SHIFT) & MASTER_DIV_MASK;
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new_parent_rate = cnd->new_rate * characteristics->divisors[div];
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for (i = 0; i < ARRAY_SIZE(characteristics->divisors); i++) {
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if (!characteristics->divisors[i])
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break;
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new_rate = DIV_ROUND_CLOSEST_ULL(new_parent_rate,
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characteristics->divisors[i]);
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tmp_diff = characteristics->output.max - new_rate;
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if (tmp_diff < 0)
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continue;
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if (best_diff < 0 || best_diff > tmp_diff) {
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new_div = characteristics->divisors[i];
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best_diff = tmp_diff;
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}
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if (!tmp_diff)
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break;
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}
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if (!new_div) {
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ret = NOTIFY_STOP_MASK;
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goto unlock;
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}
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/* Update the div to preserve MCK DIV clock rate. */
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clk_master_div_set(master_div, new_parent_rate,
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new_div);
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ret = NOTIFY_OK;
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break;
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default:
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ret = NOTIFY_DONE;
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break;
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}
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unlock:
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spin_unlock_irqrestore(master_div->lock, flags);
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return ret;
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}
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static struct notifier_block clk_master_div_notifier = {
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.notifier_call = clk_master_div_notifier_fn,
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};
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static void clk_sama7g5_master_best_diff(struct clk_rate_request *req,
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struct clk_hw *parent,
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unsigned long parent_rate,
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long *best_rate,
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long *best_diff,
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u32 div)
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{
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unsigned long tmp_rate, tmp_diff;
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if (div == MASTER_PRES_MAX)
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tmp_rate = parent_rate / 3;
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else
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tmp_rate = parent_rate >> div;
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tmp_diff = abs(req->rate - tmp_rate);
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if (*best_diff < 0 || *best_diff >= tmp_diff) {
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*best_rate = tmp_rate;
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*best_diff = tmp_diff;
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req->best_parent_rate = parent_rate;
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req->best_parent_hw = parent;
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}
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}
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static unsigned long clk_master_pres_recalc_rate(struct clk_hw *hw,
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unsigned long parent_rate)
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{
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struct clk_master *master = to_clk_master(hw);
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const struct clk_master_characteristics *characteristics =
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master->characteristics;
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unsigned long flags;
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unsigned int val, pres;
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spin_lock_irqsave(master->lock, flags);
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regmap_read(master->regmap, master->layout->offset, &val);
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spin_unlock_irqrestore(master->lock, flags);
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val &= master->layout->mask;
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pres = (val >> master->layout->pres_shift) & MASTER_PRES_MASK;
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if (pres == MASTER_PRES_MAX && characteristics->have_div3_pres)
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pres = 3;
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else
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pres = (1 << pres);
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return DIV_ROUND_CLOSEST_ULL(parent_rate, pres);
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}
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static u8 clk_master_pres_get_parent(struct clk_hw *hw)
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{
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struct clk_master *master = to_clk_master(hw);
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unsigned long flags;
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unsigned int mckr;
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spin_lock_irqsave(master->lock, flags);
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regmap_read(master->regmap, master->layout->offset, &mckr);
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spin_unlock_irqrestore(master->lock, flags);
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mckr &= master->layout->mask;
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return mckr & AT91_PMC_CSS;
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}
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static int clk_master_pres_save_context(struct clk_hw *hw)
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{
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struct clk_master *master = to_clk_master(hw);
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struct clk_hw *parent_hw = clk_hw_get_parent(hw);
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unsigned long flags;
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unsigned int val, pres;
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spin_lock_irqsave(master->lock, flags);
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regmap_read(master->regmap, master->layout->offset, &val);
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spin_unlock_irqrestore(master->lock, flags);
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val &= master->layout->mask;
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pres = (val >> master->layout->pres_shift) & MASTER_PRES_MASK;
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if (pres == MASTER_PRES_MAX && master->characteristics->have_div3_pres)
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pres = 3;
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else
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pres = (1 << pres);
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master->pms.parent = val & AT91_PMC_CSS;
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master->pms.parent_rate = clk_hw_get_rate(parent_hw);
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master->pms.rate = DIV_ROUND_CLOSEST_ULL(master->pms.parent_rate, pres);
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return 0;
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}
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static void clk_master_pres_restore_context(struct clk_hw *hw)
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{
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struct clk_master *master = to_clk_master(hw);
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unsigned long flags;
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unsigned int val, pres;
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spin_lock_irqsave(master->lock, flags);
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regmap_read(master->regmap, master->layout->offset, &val);
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spin_unlock_irqrestore(master->lock, flags);
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val &= master->layout->mask;
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pres = (val >> master->layout->pres_shift) & MASTER_PRES_MASK;
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if (pres == MASTER_PRES_MAX && master->characteristics->have_div3_pres)
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pres = 3;
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else
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pres = (1 << pres);
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if (master->pms.rate !=
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DIV_ROUND_CLOSEST_ULL(master->pms.parent_rate, pres) ||
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(master->pms.parent != (val & AT91_PMC_CSS)))
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pr_warn("MCKR PRES was not configured properly by firmware!\n");
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}
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static const struct clk_ops master_pres_ops = {
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.prepare = clk_master_prepare,
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.is_prepared = clk_master_is_prepared,
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.recalc_rate = clk_master_pres_recalc_rate,
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.get_parent = clk_master_pres_get_parent,
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.save_context = clk_master_pres_save_context,
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.restore_context = clk_master_pres_restore_context,
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};
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static struct clk_hw * __init
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at91_clk_register_master_internal(struct regmap *regmap,
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const char *name, int num_parents,
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const char **parent_names,
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const struct clk_master_layout *layout,
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const struct clk_master_characteristics *characteristics,
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const struct clk_ops *ops, spinlock_t *lock, u32 flags)
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{
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struct clk_master *master;
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struct clk_init_data init;
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struct clk_hw *hw;
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unsigned int mckr;
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unsigned long irqflags;
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int ret;
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if (!name || !num_parents || !parent_names || !lock)
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return ERR_PTR(-EINVAL);
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master = kzalloc(sizeof(*master), GFP_KERNEL);
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if (!master)
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return ERR_PTR(-ENOMEM);
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init.name = name;
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init.ops = ops;
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init.parent_names = parent_names;
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init.num_parents = num_parents;
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init.flags = flags;
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|
|
master->hw.init = &init;
|
|
master->layout = layout;
|
|
master->characteristics = characteristics;
|
|
master->regmap = regmap;
|
|
master->lock = lock;
|
|
|
|
if (ops == &master_div_ops_chg) {
|
|
spin_lock_irqsave(master->lock, irqflags);
|
|
regmap_read(master->regmap, master->layout->offset, &mckr);
|
|
spin_unlock_irqrestore(master->lock, irqflags);
|
|
|
|
mckr &= layout->mask;
|
|
mckr = (mckr >> MASTER_DIV_SHIFT) & MASTER_DIV_MASK;
|
|
master->div = characteristics->divisors[mckr];
|
|
}
|
|
|
|
hw = &master->hw;
|
|
ret = clk_hw_register(NULL, &master->hw);
|
|
if (ret) {
|
|
kfree(master);
|
|
hw = ERR_PTR(ret);
|
|
}
|
|
|
|
return hw;
|
|
}
|
|
|
|
struct clk_hw * __init
|
|
at91_clk_register_master_pres(struct regmap *regmap,
|
|
const char *name, int num_parents,
|
|
const char **parent_names,
|
|
const struct clk_master_layout *layout,
|
|
const struct clk_master_characteristics *characteristics,
|
|
spinlock_t *lock)
|
|
{
|
|
return at91_clk_register_master_internal(regmap, name, num_parents,
|
|
parent_names, layout,
|
|
characteristics,
|
|
&master_pres_ops,
|
|
lock, CLK_SET_RATE_GATE);
|
|
}
|
|
|
|
struct clk_hw * __init
|
|
at91_clk_register_master_div(struct regmap *regmap,
|
|
const char *name, const char *parent_name,
|
|
const struct clk_master_layout *layout,
|
|
const struct clk_master_characteristics *characteristics,
|
|
spinlock_t *lock, u32 flags, u32 safe_div)
|
|
{
|
|
const struct clk_ops *ops;
|
|
struct clk_hw *hw;
|
|
|
|
if (flags & CLK_SET_RATE_GATE)
|
|
ops = &master_div_ops;
|
|
else
|
|
ops = &master_div_ops_chg;
|
|
|
|
hw = at91_clk_register_master_internal(regmap, name, 1,
|
|
&parent_name, layout,
|
|
characteristics, ops,
|
|
lock, flags);
|
|
|
|
if (!IS_ERR(hw) && safe_div) {
|
|
master_div = to_clk_master(hw);
|
|
master_div->safe_div = safe_div;
|
|
clk_notifier_register(hw->clk,
|
|
&clk_master_div_notifier);
|
|
}
|
|
|
|
return hw;
|
|
}
|
|
|
|
static unsigned long
|
|
clk_sama7g5_master_recalc_rate(struct clk_hw *hw,
|
|
unsigned long parent_rate)
|
|
{
|
|
struct clk_master *master = to_clk_master(hw);
|
|
|
|
return DIV_ROUND_CLOSEST_ULL(parent_rate, (1 << master->div));
|
|
}
|
|
|
|
static int clk_sama7g5_master_determine_rate(struct clk_hw *hw,
|
|
struct clk_rate_request *req)
|
|
{
|
|
struct clk_master *master = to_clk_master(hw);
|
|
struct clk_rate_request req_parent = *req;
|
|
struct clk_hw *parent;
|
|
long best_rate = LONG_MIN, best_diff = LONG_MIN;
|
|
unsigned long parent_rate;
|
|
unsigned int div, i;
|
|
|
|
/* First: check the dividers of MCR. */
|
|
for (i = 0; i < clk_hw_get_num_parents(hw); i++) {
|
|
parent = clk_hw_get_parent_by_index(hw, i);
|
|
if (!parent)
|
|
continue;
|
|
|
|
parent_rate = clk_hw_get_rate(parent);
|
|
if (!parent_rate)
|
|
continue;
|
|
|
|
for (div = 0; div < MASTER_PRES_MAX + 1; div++) {
|
|
clk_sama7g5_master_best_diff(req, parent, parent_rate,
|
|
&best_rate, &best_diff,
|
|
div);
|
|
if (!best_diff)
|
|
break;
|
|
}
|
|
|
|
if (!best_diff)
|
|
break;
|
|
}
|
|
|
|
/* Second: try to request rate form changeable parent. */
|
|
if (master->chg_pid < 0)
|
|
goto end;
|
|
|
|
parent = clk_hw_get_parent_by_index(hw, master->chg_pid);
|
|
if (!parent)
|
|
goto end;
|
|
|
|
for (div = 0; div < MASTER_PRES_MAX + 1; div++) {
|
|
if (div == MASTER_PRES_MAX)
|
|
req_parent.rate = req->rate * 3;
|
|
else
|
|
req_parent.rate = req->rate << div;
|
|
|
|
if (__clk_determine_rate(parent, &req_parent))
|
|
continue;
|
|
|
|
clk_sama7g5_master_best_diff(req, parent, req_parent.rate,
|
|
&best_rate, &best_diff, div);
|
|
|
|
if (!best_diff)
|
|
break;
|
|
}
|
|
|
|
end:
|
|
pr_debug("MCK: %s, best_rate = %ld, parent clk: %s @ %ld\n",
|
|
__func__, best_rate,
|
|
__clk_get_name((req->best_parent_hw)->clk),
|
|
req->best_parent_rate);
|
|
|
|
if (best_rate < 0)
|
|
return -EINVAL;
|
|
|
|
req->rate = best_rate;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static u8 clk_sama7g5_master_get_parent(struct clk_hw *hw)
|
|
{
|
|
struct clk_master *master = to_clk_master(hw);
|
|
unsigned long flags;
|
|
u8 index;
|
|
|
|
spin_lock_irqsave(master->lock, flags);
|
|
index = clk_mux_val_to_index(&master->hw, master->mux_table, 0,
|
|
master->parent);
|
|
spin_unlock_irqrestore(master->lock, flags);
|
|
|
|
return index;
|
|
}
|
|
|
|
static int clk_sama7g5_master_set_parent(struct clk_hw *hw, u8 index)
|
|
{
|
|
struct clk_master *master = to_clk_master(hw);
|
|
unsigned long flags;
|
|
|
|
if (index >= clk_hw_get_num_parents(hw))
|
|
return -EINVAL;
|
|
|
|
spin_lock_irqsave(master->lock, flags);
|
|
master->parent = clk_mux_index_to_val(master->mux_table, 0, index);
|
|
spin_unlock_irqrestore(master->lock, flags);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void clk_sama7g5_master_set(struct clk_master *master,
|
|
unsigned int status)
|
|
{
|
|
unsigned long flags;
|
|
unsigned int val, cparent;
|
|
unsigned int enable = status ? AT91_PMC_MCR_V2_EN : 0;
|
|
unsigned int parent = master->parent << PMC_MCR_CSS_SHIFT;
|
|
unsigned int div = master->div << MASTER_DIV_SHIFT;
|
|
|
|
spin_lock_irqsave(master->lock, flags);
|
|
|
|
regmap_write(master->regmap, AT91_PMC_MCR_V2,
|
|
AT91_PMC_MCR_V2_ID(master->id));
|
|
regmap_read(master->regmap, AT91_PMC_MCR_V2, &val);
|
|
regmap_update_bits(master->regmap, AT91_PMC_MCR_V2,
|
|
enable | AT91_PMC_MCR_V2_CSS | AT91_PMC_MCR_V2_DIV |
|
|
AT91_PMC_MCR_V2_CMD | AT91_PMC_MCR_V2_ID_MSK,
|
|
enable | parent | div | AT91_PMC_MCR_V2_CMD |
|
|
AT91_PMC_MCR_V2_ID(master->id));
|
|
|
|
cparent = (val & AT91_PMC_MCR_V2_CSS) >> PMC_MCR_CSS_SHIFT;
|
|
|
|
/* Wait here only if parent is being changed. */
|
|
while ((cparent != master->parent) && !clk_master_ready(master))
|
|
cpu_relax();
|
|
|
|
spin_unlock_irqrestore(master->lock, flags);
|
|
}
|
|
|
|
static int clk_sama7g5_master_enable(struct clk_hw *hw)
|
|
{
|
|
struct clk_master *master = to_clk_master(hw);
|
|
|
|
clk_sama7g5_master_set(master, 1);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void clk_sama7g5_master_disable(struct clk_hw *hw)
|
|
{
|
|
struct clk_master *master = to_clk_master(hw);
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(master->lock, flags);
|
|
|
|
regmap_write(master->regmap, AT91_PMC_MCR_V2, master->id);
|
|
regmap_update_bits(master->regmap, AT91_PMC_MCR_V2,
|
|
AT91_PMC_MCR_V2_EN | AT91_PMC_MCR_V2_CMD |
|
|
AT91_PMC_MCR_V2_ID_MSK,
|
|
AT91_PMC_MCR_V2_CMD |
|
|
AT91_PMC_MCR_V2_ID(master->id));
|
|
|
|
spin_unlock_irqrestore(master->lock, flags);
|
|
}
|
|
|
|
static int clk_sama7g5_master_is_enabled(struct clk_hw *hw)
|
|
{
|
|
struct clk_master *master = to_clk_master(hw);
|
|
unsigned long flags;
|
|
unsigned int val;
|
|
|
|
spin_lock_irqsave(master->lock, flags);
|
|
|
|
regmap_write(master->regmap, AT91_PMC_MCR_V2, master->id);
|
|
regmap_read(master->regmap, AT91_PMC_MCR_V2, &val);
|
|
|
|
spin_unlock_irqrestore(master->lock, flags);
|
|
|
|
return !!(val & AT91_PMC_MCR_V2_EN);
|
|
}
|
|
|
|
static int clk_sama7g5_master_set_rate(struct clk_hw *hw, unsigned long rate,
|
|
unsigned long parent_rate)
|
|
{
|
|
struct clk_master *master = to_clk_master(hw);
|
|
unsigned long div, flags;
|
|
|
|
div = DIV_ROUND_CLOSEST(parent_rate, rate);
|
|
if ((div > (1 << (MASTER_PRES_MAX - 1))) || (div & (div - 1)))
|
|
return -EINVAL;
|
|
|
|
if (div == 3)
|
|
div = MASTER_PRES_MAX;
|
|
else if (div)
|
|
div = ffs(div) - 1;
|
|
|
|
spin_lock_irqsave(master->lock, flags);
|
|
master->div = div;
|
|
spin_unlock_irqrestore(master->lock, flags);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int clk_sama7g5_master_save_context(struct clk_hw *hw)
|
|
{
|
|
struct clk_master *master = to_clk_master(hw);
|
|
|
|
master->pms.status = clk_sama7g5_master_is_enabled(hw);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void clk_sama7g5_master_restore_context(struct clk_hw *hw)
|
|
{
|
|
struct clk_master *master = to_clk_master(hw);
|
|
|
|
if (master->pms.status)
|
|
clk_sama7g5_master_set(master, master->pms.status);
|
|
}
|
|
|
|
static const struct clk_ops sama7g5_master_ops = {
|
|
.enable = clk_sama7g5_master_enable,
|
|
.disable = clk_sama7g5_master_disable,
|
|
.is_enabled = clk_sama7g5_master_is_enabled,
|
|
.recalc_rate = clk_sama7g5_master_recalc_rate,
|
|
.determine_rate = clk_sama7g5_master_determine_rate,
|
|
.set_rate = clk_sama7g5_master_set_rate,
|
|
.get_parent = clk_sama7g5_master_get_parent,
|
|
.set_parent = clk_sama7g5_master_set_parent,
|
|
.save_context = clk_sama7g5_master_save_context,
|
|
.restore_context = clk_sama7g5_master_restore_context,
|
|
};
|
|
|
|
struct clk_hw * __init
|
|
at91_clk_sama7g5_register_master(struct regmap *regmap,
|
|
const char *name, int num_parents,
|
|
const char **parent_names,
|
|
u32 *mux_table,
|
|
spinlock_t *lock, u8 id,
|
|
bool critical, int chg_pid)
|
|
{
|
|
struct clk_master *master;
|
|
struct clk_hw *hw;
|
|
struct clk_init_data init;
|
|
unsigned long flags;
|
|
unsigned int val;
|
|
int ret;
|
|
|
|
if (!name || !num_parents || !parent_names || !mux_table ||
|
|
!lock || id > MASTER_MAX_ID)
|
|
return ERR_PTR(-EINVAL);
|
|
|
|
master = kzalloc(sizeof(*master), GFP_KERNEL);
|
|
if (!master)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
init.name = name;
|
|
init.ops = &sama7g5_master_ops;
|
|
init.parent_names = parent_names;
|
|
init.num_parents = num_parents;
|
|
init.flags = CLK_SET_RATE_GATE | CLK_SET_PARENT_GATE;
|
|
if (chg_pid >= 0)
|
|
init.flags |= CLK_SET_RATE_PARENT;
|
|
if (critical)
|
|
init.flags |= CLK_IS_CRITICAL;
|
|
|
|
master->hw.init = &init;
|
|
master->regmap = regmap;
|
|
master->id = id;
|
|
master->chg_pid = chg_pid;
|
|
master->lock = lock;
|
|
master->mux_table = mux_table;
|
|
|
|
spin_lock_irqsave(master->lock, flags);
|
|
regmap_write(master->regmap, AT91_PMC_MCR_V2, master->id);
|
|
regmap_read(master->regmap, AT91_PMC_MCR_V2, &val);
|
|
master->parent = (val & AT91_PMC_MCR_V2_CSS) >> PMC_MCR_CSS_SHIFT;
|
|
master->div = (val & AT91_PMC_MCR_V2_DIV) >> MASTER_DIV_SHIFT;
|
|
spin_unlock_irqrestore(master->lock, flags);
|
|
|
|
hw = &master->hw;
|
|
ret = clk_hw_register(NULL, &master->hw);
|
|
if (ret) {
|
|
kfree(master);
|
|
hw = ERR_PTR(ret);
|
|
}
|
|
|
|
return hw;
|
|
}
|
|
|
|
const struct clk_master_layout at91rm9200_master_layout = {
|
|
.mask = 0x31F,
|
|
.pres_shift = 2,
|
|
.offset = AT91_PMC_MCKR,
|
|
};
|
|
|
|
const struct clk_master_layout at91sam9x5_master_layout = {
|
|
.mask = 0x373,
|
|
.pres_shift = 4,
|
|
.offset = AT91_PMC_MCKR,
|
|
};
|