File-copy from v4.4.100
This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Please refer to that tree for all history prior to this point.
Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/arch/arm/mach-davinci/clock.c b/arch/arm/mach-davinci/clock.c
new file mode 100644
index 0000000..3caff96
--- /dev/null
+++ b/arch/arm/mach-davinci/clock.c
@@ -0,0 +1,719 @@
+/*
+ * Clock and PLL control for DaVinci devices
+ *
+ * Copyright (C) 2006-2007 Texas Instruments.
+ * Copyright (C) 2008-2009 Deep Root Systems, LLC
+ *
+ * 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/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/mutex.h>
+#include <linux/io.h>
+#include <linux/delay.h>
+
+#include <mach/hardware.h>
+
+#include <mach/clock.h>
+#include <mach/psc.h>
+#include <mach/cputype.h>
+#include "clock.h"
+
+static LIST_HEAD(clocks);
+static DEFINE_MUTEX(clocks_mutex);
+static DEFINE_SPINLOCK(clockfw_lock);
+
+static void __clk_enable(struct clk *clk)
+{
+ if (clk->parent)
+ __clk_enable(clk->parent);
+ if (clk->usecount++ == 0) {
+ if (clk->flags & CLK_PSC)
+ davinci_psc_config(clk->domain, clk->gpsc, clk->lpsc,
+ true, clk->flags);
+ else if (clk->clk_enable)
+ clk->clk_enable(clk);
+ }
+}
+
+static void __clk_disable(struct clk *clk)
+{
+ if (WARN_ON(clk->usecount == 0))
+ return;
+ if (--clk->usecount == 0) {
+ if (!(clk->flags & CLK_PLL) && (clk->flags & CLK_PSC))
+ davinci_psc_config(clk->domain, clk->gpsc, clk->lpsc,
+ false, clk->flags);
+ else if (clk->clk_disable)
+ clk->clk_disable(clk);
+ }
+ if (clk->parent)
+ __clk_disable(clk->parent);
+}
+
+int davinci_clk_reset(struct clk *clk, bool reset)
+{
+ unsigned long flags;
+
+ if (clk == NULL || IS_ERR(clk))
+ return -EINVAL;
+
+ spin_lock_irqsave(&clockfw_lock, flags);
+ if (clk->flags & CLK_PSC)
+ davinci_psc_reset(clk->gpsc, clk->lpsc, reset);
+ spin_unlock_irqrestore(&clockfw_lock, flags);
+
+ return 0;
+}
+EXPORT_SYMBOL(davinci_clk_reset);
+
+int davinci_clk_reset_assert(struct clk *clk)
+{
+ if (clk == NULL || IS_ERR(clk) || !clk->reset)
+ return -EINVAL;
+
+ return clk->reset(clk, true);
+}
+EXPORT_SYMBOL(davinci_clk_reset_assert);
+
+int davinci_clk_reset_deassert(struct clk *clk)
+{
+ if (clk == NULL || IS_ERR(clk) || !clk->reset)
+ return -EINVAL;
+
+ return clk->reset(clk, false);
+}
+EXPORT_SYMBOL(davinci_clk_reset_deassert);
+
+int clk_enable(struct clk *clk)
+{
+ unsigned long flags;
+
+ if (!clk)
+ return 0;
+ else if (IS_ERR(clk))
+ return -EINVAL;
+
+ spin_lock_irqsave(&clockfw_lock, flags);
+ __clk_enable(clk);
+ spin_unlock_irqrestore(&clockfw_lock, flags);
+
+ return 0;
+}
+EXPORT_SYMBOL(clk_enable);
+
+void clk_disable(struct clk *clk)
+{
+ unsigned long flags;
+
+ if (clk == NULL || IS_ERR(clk))
+ return;
+
+ spin_lock_irqsave(&clockfw_lock, flags);
+ __clk_disable(clk);
+ spin_unlock_irqrestore(&clockfw_lock, flags);
+}
+EXPORT_SYMBOL(clk_disable);
+
+unsigned long clk_get_rate(struct clk *clk)
+{
+ if (clk == NULL || IS_ERR(clk))
+ return 0;
+
+ return clk->rate;
+}
+EXPORT_SYMBOL(clk_get_rate);
+
+long clk_round_rate(struct clk *clk, unsigned long rate)
+{
+ if (clk == NULL || IS_ERR(clk))
+ return 0;
+
+ if (clk->round_rate)
+ return clk->round_rate(clk, rate);
+
+ return clk->rate;
+}
+EXPORT_SYMBOL(clk_round_rate);
+
+/* Propagate rate to children */
+static void propagate_rate(struct clk *root)
+{
+ struct clk *clk;
+
+ list_for_each_entry(clk, &root->children, childnode) {
+ if (clk->recalc)
+ clk->rate = clk->recalc(clk);
+ propagate_rate(clk);
+ }
+}
+
+int clk_set_rate(struct clk *clk, unsigned long rate)
+{
+ unsigned long flags;
+ int ret = -EINVAL;
+
+ if (!clk)
+ return 0;
+ else if (IS_ERR(clk))
+ return -EINVAL;
+
+ if (clk->set_rate)
+ ret = clk->set_rate(clk, rate);
+
+ spin_lock_irqsave(&clockfw_lock, flags);
+ if (ret == 0) {
+ if (clk->recalc)
+ clk->rate = clk->recalc(clk);
+ propagate_rate(clk);
+ }
+ spin_unlock_irqrestore(&clockfw_lock, flags);
+
+ return ret;
+}
+EXPORT_SYMBOL(clk_set_rate);
+
+int clk_set_parent(struct clk *clk, struct clk *parent)
+{
+ unsigned long flags;
+
+ if (!clk)
+ return 0;
+ else if (IS_ERR(clk))
+ return -EINVAL;
+
+ /* Cannot change parent on enabled clock */
+ if (WARN_ON(clk->usecount))
+ return -EINVAL;
+
+ mutex_lock(&clocks_mutex);
+ clk->parent = parent;
+ list_del_init(&clk->childnode);
+ list_add(&clk->childnode, &clk->parent->children);
+ mutex_unlock(&clocks_mutex);
+
+ spin_lock_irqsave(&clockfw_lock, flags);
+ if (clk->recalc)
+ clk->rate = clk->recalc(clk);
+ propagate_rate(clk);
+ spin_unlock_irqrestore(&clockfw_lock, flags);
+
+ return 0;
+}
+EXPORT_SYMBOL(clk_set_parent);
+
+int clk_register(struct clk *clk)
+{
+ if (clk == NULL || IS_ERR(clk))
+ return -EINVAL;
+
+ if (WARN(clk->parent && !clk->parent->rate,
+ "CLK: %s parent %s has no rate!\n",
+ clk->name, clk->parent->name))
+ return -EINVAL;
+
+ INIT_LIST_HEAD(&clk->children);
+
+ mutex_lock(&clocks_mutex);
+ list_add_tail(&clk->node, &clocks);
+ if (clk->parent)
+ list_add_tail(&clk->childnode, &clk->parent->children);
+ mutex_unlock(&clocks_mutex);
+
+ /* If rate is already set, use it */
+ if (clk->rate)
+ return 0;
+
+ /* Else, see if there is a way to calculate it */
+ if (clk->recalc)
+ clk->rate = clk->recalc(clk);
+
+ /* Otherwise, default to parent rate */
+ else if (clk->parent)
+ clk->rate = clk->parent->rate;
+
+ return 0;
+}
+EXPORT_SYMBOL(clk_register);
+
+void clk_unregister(struct clk *clk)
+{
+ if (clk == NULL || IS_ERR(clk))
+ return;
+
+ mutex_lock(&clocks_mutex);
+ list_del(&clk->node);
+ list_del(&clk->childnode);
+ mutex_unlock(&clocks_mutex);
+}
+EXPORT_SYMBOL(clk_unregister);
+
+#ifdef CONFIG_DAVINCI_RESET_CLOCKS
+/*
+ * Disable any unused clocks left on by the bootloader
+ */
+int __init davinci_clk_disable_unused(void)
+{
+ struct clk *ck;
+
+ spin_lock_irq(&clockfw_lock);
+ list_for_each_entry(ck, &clocks, node) {
+ if (ck->usecount > 0)
+ continue;
+ if (!(ck->flags & CLK_PSC))
+ continue;
+
+ /* ignore if in Disabled or SwRstDisable states */
+ if (!davinci_psc_is_clk_active(ck->gpsc, ck->lpsc))
+ continue;
+
+ pr_debug("Clocks: disable unused %s\n", ck->name);
+
+ davinci_psc_config(ck->domain, ck->gpsc, ck->lpsc,
+ false, ck->flags);
+ }
+ spin_unlock_irq(&clockfw_lock);
+
+ return 0;
+}
+#endif
+
+static unsigned long clk_sysclk_recalc(struct clk *clk)
+{
+ u32 v, plldiv;
+ struct pll_data *pll;
+ unsigned long rate = clk->rate;
+
+ /* If this is the PLL base clock, no more calculations needed */
+ if (clk->pll_data)
+ return rate;
+
+ if (WARN_ON(!clk->parent))
+ return rate;
+
+ rate = clk->parent->rate;
+
+ /* Otherwise, the parent must be a PLL */
+ if (WARN_ON(!clk->parent->pll_data))
+ return rate;
+
+ pll = clk->parent->pll_data;
+
+ /* If pre-PLL, source clock is before the multiplier and divider(s) */
+ if (clk->flags & PRE_PLL)
+ rate = pll->input_rate;
+
+ if (!clk->div_reg)
+ return rate;
+
+ v = __raw_readl(pll->base + clk->div_reg);
+ if (v & PLLDIV_EN) {
+ plldiv = (v & pll->div_ratio_mask) + 1;
+ if (plldiv)
+ rate /= plldiv;
+ }
+
+ return rate;
+}
+
+int davinci_set_sysclk_rate(struct clk *clk, unsigned long rate)
+{
+ unsigned v;
+ struct pll_data *pll;
+ unsigned long input;
+ unsigned ratio = 0;
+
+ /* If this is the PLL base clock, wrong function to call */
+ if (clk->pll_data)
+ return -EINVAL;
+
+ /* There must be a parent... */
+ if (WARN_ON(!clk->parent))
+ return -EINVAL;
+
+ /* ... the parent must be a PLL... */
+ if (WARN_ON(!clk->parent->pll_data))
+ return -EINVAL;
+
+ /* ... and this clock must have a divider. */
+ if (WARN_ON(!clk->div_reg))
+ return -EINVAL;
+
+ pll = clk->parent->pll_data;
+
+ input = clk->parent->rate;
+
+ /* If pre-PLL, source clock is before the multiplier and divider(s) */
+ if (clk->flags & PRE_PLL)
+ input = pll->input_rate;
+
+ if (input > rate) {
+ /*
+ * Can afford to provide an output little higher than requested
+ * only if maximum rate supported by hardware on this sysclk
+ * is known.
+ */
+ if (clk->maxrate) {
+ ratio = DIV_ROUND_CLOSEST(input, rate);
+ if (input / ratio > clk->maxrate)
+ ratio = 0;
+ }
+
+ if (ratio == 0)
+ ratio = DIV_ROUND_UP(input, rate);
+
+ ratio--;
+ }
+
+ if (ratio > pll->div_ratio_mask)
+ return -EINVAL;
+
+ do {
+ v = __raw_readl(pll->base + PLLSTAT);
+ } while (v & PLLSTAT_GOSTAT);
+
+ v = __raw_readl(pll->base + clk->div_reg);
+ v &= ~pll->div_ratio_mask;
+ v |= ratio | PLLDIV_EN;
+ __raw_writel(v, pll->base + clk->div_reg);
+
+ v = __raw_readl(pll->base + PLLCMD);
+ v |= PLLCMD_GOSET;
+ __raw_writel(v, pll->base + PLLCMD);
+
+ do {
+ v = __raw_readl(pll->base + PLLSTAT);
+ } while (v & PLLSTAT_GOSTAT);
+
+ return 0;
+}
+EXPORT_SYMBOL(davinci_set_sysclk_rate);
+
+static unsigned long clk_leafclk_recalc(struct clk *clk)
+{
+ if (WARN_ON(!clk->parent))
+ return clk->rate;
+
+ return clk->parent->rate;
+}
+
+int davinci_simple_set_rate(struct clk *clk, unsigned long rate)
+{
+ clk->rate = rate;
+ return 0;
+}
+
+static unsigned long clk_pllclk_recalc(struct clk *clk)
+{
+ u32 ctrl, mult = 1, prediv = 1, postdiv = 1;
+ u8 bypass;
+ struct pll_data *pll = clk->pll_data;
+ unsigned long rate = clk->rate;
+
+ ctrl = __raw_readl(pll->base + PLLCTL);
+ rate = pll->input_rate = clk->parent->rate;
+
+ if (ctrl & PLLCTL_PLLEN) {
+ bypass = 0;
+ mult = __raw_readl(pll->base + PLLM);
+ if (cpu_is_davinci_dm365())
+ mult = 2 * (mult & PLLM_PLLM_MASK);
+ else
+ mult = (mult & PLLM_PLLM_MASK) + 1;
+ } else
+ bypass = 1;
+
+ if (pll->flags & PLL_HAS_PREDIV) {
+ prediv = __raw_readl(pll->base + PREDIV);
+ if (prediv & PLLDIV_EN)
+ prediv = (prediv & pll->div_ratio_mask) + 1;
+ else
+ prediv = 1;
+ }
+
+ /* pre-divider is fixed, but (some?) chips won't report that */
+ if (cpu_is_davinci_dm355() && pll->num == 1)
+ prediv = 8;
+
+ if (pll->flags & PLL_HAS_POSTDIV) {
+ postdiv = __raw_readl(pll->base + POSTDIV);
+ if (postdiv & PLLDIV_EN)
+ postdiv = (postdiv & pll->div_ratio_mask) + 1;
+ else
+ postdiv = 1;
+ }
+
+ if (!bypass) {
+ rate /= prediv;
+ rate *= mult;
+ rate /= postdiv;
+ }
+
+ pr_debug("PLL%d: input = %lu MHz [ ",
+ pll->num, clk->parent->rate / 1000000);
+ if (bypass)
+ pr_debug("bypass ");
+ if (prediv > 1)
+ pr_debug("/ %d ", prediv);
+ if (mult > 1)
+ pr_debug("* %d ", mult);
+ if (postdiv > 1)
+ pr_debug("/ %d ", postdiv);
+ pr_debug("] --> %lu MHz output.\n", rate / 1000000);
+
+ return rate;
+}
+
+/**
+ * davinci_set_pllrate - set the output rate of a given PLL.
+ *
+ * Note: Currently tested to work with OMAP-L138 only.
+ *
+ * @pll: pll whose rate needs to be changed.
+ * @prediv: The pre divider value. Passing 0 disables the pre-divider.
+ * @pllm: The multiplier value. Passing 0 leads to multiply-by-one.
+ * @postdiv: The post divider value. Passing 0 disables the post-divider.
+ */
+int davinci_set_pllrate(struct pll_data *pll, unsigned int prediv,
+ unsigned int mult, unsigned int postdiv)
+{
+ u32 ctrl;
+ unsigned int locktime;
+ unsigned long flags;
+
+ if (pll->base == NULL)
+ return -EINVAL;
+
+ /*
+ * PLL lock time required per OMAP-L138 datasheet is
+ * (2000 * prediv)/sqrt(pllm) OSCIN cycles. We approximate sqrt(pllm)
+ * as 4 and OSCIN cycle as 25 MHz.
+ */
+ if (prediv) {
+ locktime = ((2000 * prediv) / 100);
+ prediv = (prediv - 1) | PLLDIV_EN;
+ } else {
+ locktime = PLL_LOCK_TIME;
+ }
+ if (postdiv)
+ postdiv = (postdiv - 1) | PLLDIV_EN;
+ if (mult)
+ mult = mult - 1;
+
+ /* Protect against simultaneous calls to PLL setting seqeunce */
+ spin_lock_irqsave(&clockfw_lock, flags);
+
+ ctrl = __raw_readl(pll->base + PLLCTL);
+
+ /* Switch the PLL to bypass mode */
+ ctrl &= ~(PLLCTL_PLLENSRC | PLLCTL_PLLEN);
+ __raw_writel(ctrl, pll->base + PLLCTL);
+
+ udelay(PLL_BYPASS_TIME);
+
+ /* Reset and enable PLL */
+ ctrl &= ~(PLLCTL_PLLRST | PLLCTL_PLLDIS);
+ __raw_writel(ctrl, pll->base + PLLCTL);
+
+ if (pll->flags & PLL_HAS_PREDIV)
+ __raw_writel(prediv, pll->base + PREDIV);
+
+ __raw_writel(mult, pll->base + PLLM);
+
+ if (pll->flags & PLL_HAS_POSTDIV)
+ __raw_writel(postdiv, pll->base + POSTDIV);
+
+ udelay(PLL_RESET_TIME);
+
+ /* Bring PLL out of reset */
+ ctrl |= PLLCTL_PLLRST;
+ __raw_writel(ctrl, pll->base + PLLCTL);
+
+ udelay(locktime);
+
+ /* Remove PLL from bypass mode */
+ ctrl |= PLLCTL_PLLEN;
+ __raw_writel(ctrl, pll->base + PLLCTL);
+
+ spin_unlock_irqrestore(&clockfw_lock, flags);
+
+ return 0;
+}
+EXPORT_SYMBOL(davinci_set_pllrate);
+
+/**
+ * davinci_set_refclk_rate() - Set the reference clock rate
+ * @rate: The new rate.
+ *
+ * Sets the reference clock rate to a given value. This will most likely
+ * result in the entire clock tree getting updated.
+ *
+ * This is used to support boards which use a reference clock different
+ * than that used by default in <soc>.c file. The reference clock rate
+ * should be updated early in the boot process; ideally soon after the
+ * clock tree has been initialized once with the default reference clock
+ * rate (davinci_common_init()).
+ *
+ * Returns 0 on success, error otherwise.
+ */
+int davinci_set_refclk_rate(unsigned long rate)
+{
+ struct clk *refclk;
+
+ refclk = clk_get(NULL, "ref");
+ if (IS_ERR(refclk)) {
+ pr_err("%s: failed to get reference clock\n", __func__);
+ return PTR_ERR(refclk);
+ }
+
+ clk_set_rate(refclk, rate);
+
+ clk_put(refclk);
+
+ return 0;
+}
+
+int __init davinci_clk_init(struct clk_lookup *clocks)
+{
+ struct clk_lookup *c;
+ struct clk *clk;
+ size_t num_clocks = 0;
+
+ for (c = clocks; c->clk; c++) {
+ clk = c->clk;
+
+ if (!clk->recalc) {
+
+ /* Check if clock is a PLL */
+ if (clk->pll_data)
+ clk->recalc = clk_pllclk_recalc;
+
+ /* Else, if it is a PLL-derived clock */
+ else if (clk->flags & CLK_PLL)
+ clk->recalc = clk_sysclk_recalc;
+
+ /* Otherwise, it is a leaf clock (PSC clock) */
+ else if (clk->parent)
+ clk->recalc = clk_leafclk_recalc;
+ }
+
+ if (clk->pll_data) {
+ struct pll_data *pll = clk->pll_data;
+
+ if (!pll->div_ratio_mask)
+ pll->div_ratio_mask = PLLDIV_RATIO_MASK;
+
+ if (pll->phys_base && !pll->base) {
+ pll->base = ioremap(pll->phys_base, SZ_4K);
+ WARN_ON(!pll->base);
+ }
+ }
+
+ if (clk->recalc)
+ clk->rate = clk->recalc(clk);
+
+ if (clk->lpsc)
+ clk->flags |= CLK_PSC;
+
+ if (clk->flags & PSC_LRST)
+ clk->reset = davinci_clk_reset;
+
+ clk_register(clk);
+ num_clocks++;
+
+ /* Turn on clocks that Linux doesn't otherwise manage */
+ if (clk->flags & ALWAYS_ENABLED)
+ clk_enable(clk);
+ }
+
+ clkdev_add_table(clocks, num_clocks);
+
+ return 0;
+}
+
+#ifdef CONFIG_DEBUG_FS
+
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+
+#define CLKNAME_MAX 10 /* longest clock name */
+#define NEST_DELTA 2
+#define NEST_MAX 4
+
+static void
+dump_clock(struct seq_file *s, unsigned nest, struct clk *parent)
+{
+ char *state;
+ char buf[CLKNAME_MAX + NEST_DELTA * NEST_MAX];
+ struct clk *clk;
+ unsigned i;
+
+ if (parent->flags & CLK_PLL)
+ state = "pll";
+ else if (parent->flags & CLK_PSC)
+ state = "psc";
+ else
+ state = "";
+
+ /* <nest spaces> name <pad to end> */
+ memset(buf, ' ', sizeof(buf) - 1);
+ buf[sizeof(buf) - 1] = 0;
+ i = strlen(parent->name);
+ memcpy(buf + nest, parent->name,
+ min(i, (unsigned)(sizeof(buf) - 1 - nest)));
+
+ seq_printf(s, "%s users=%2d %-3s %9ld Hz\n",
+ buf, parent->usecount, state, clk_get_rate(parent));
+ /* REVISIT show device associations too */
+
+ /* cost is now small, but not linear... */
+ list_for_each_entry(clk, &parent->children, childnode) {
+ dump_clock(s, nest + NEST_DELTA, clk);
+ }
+}
+
+static int davinci_ck_show(struct seq_file *m, void *v)
+{
+ struct clk *clk;
+
+ /*
+ * Show clock tree; We trust nonzero usecounts equate to PSC enables...
+ */
+ mutex_lock(&clocks_mutex);
+ list_for_each_entry(clk, &clocks, node)
+ if (!clk->parent)
+ dump_clock(m, 0, clk);
+ mutex_unlock(&clocks_mutex);
+
+ return 0;
+}
+
+static int davinci_ck_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, davinci_ck_show, NULL);
+}
+
+static const struct file_operations davinci_ck_operations = {
+ .open = davinci_ck_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static int __init davinci_clk_debugfs_init(void)
+{
+ debugfs_create_file("davinci_clocks", S_IFREG | S_IRUGO, NULL, NULL,
+ &davinci_ck_operations);
+ return 0;
+
+}
+device_initcall(davinci_clk_debugfs_init);
+#endif /* CONFIG_DEBUG_FS */