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-rw-r--r--arch/arm/mach-omap1/clock.c1104
1 files changed, 1104 insertions, 0 deletions
diff --git a/arch/arm/mach-omap1/clock.c b/arch/arm/mach-omap1/clock.c
new file mode 100644
index 000000000..4f5fd4a08
--- /dev/null
+++ b/arch/arm/mach-omap1/clock.c
@@ -0,0 +1,1104 @@
+/*
+ * linux/arch/arm/mach-omap1/clock.c
+ *
+ * Copyright (C) 2004 - 2005, 2009-2010 Nokia Corporation
+ * Written by Tuukka Tikkanen <tuukka.tikkanen@elektrobit.com>
+ *
+ * Modified to use omap shared clock framework by
+ * Tony Lindgren <tony@atomide.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/kernel.h>
+#include <linux/export.h>
+#include <linux/list.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/clkdev.h>
+
+#include <asm/mach-types.h>
+
+#include <mach/hardware.h>
+
+#include "soc.h"
+#include "iomap.h"
+#include "clock.h"
+#include "opp.h"
+#include "sram.h"
+
+__u32 arm_idlect1_mask;
+struct clk *api_ck_p, *ck_dpll1_p, *ck_ref_p;
+
+static LIST_HEAD(clocks);
+static DEFINE_MUTEX(clocks_mutex);
+static DEFINE_SPINLOCK(clockfw_lock);
+
+/*
+ * Omap1 specific clock functions
+ */
+
+unsigned long omap1_uart_recalc(struct clk *clk)
+{
+ unsigned int val = __raw_readl(clk->enable_reg);
+ return val & clk->enable_bit ? 48000000 : 12000000;
+}
+
+unsigned long omap1_sossi_recalc(struct clk *clk)
+{
+ u32 div = omap_readl(MOD_CONF_CTRL_1);
+
+ div = (div >> 17) & 0x7;
+ div++;
+
+ return clk->parent->rate / div;
+}
+
+static void omap1_clk_allow_idle(struct clk *clk)
+{
+ struct arm_idlect1_clk * iclk = (struct arm_idlect1_clk *)clk;
+
+ if (!(clk->flags & CLOCK_IDLE_CONTROL))
+ return;
+
+ if (iclk->no_idle_count > 0 && !(--iclk->no_idle_count))
+ arm_idlect1_mask |= 1 << iclk->idlect_shift;
+}
+
+static void omap1_clk_deny_idle(struct clk *clk)
+{
+ struct arm_idlect1_clk * iclk = (struct arm_idlect1_clk *)clk;
+
+ if (!(clk->flags & CLOCK_IDLE_CONTROL))
+ return;
+
+ if (iclk->no_idle_count++ == 0)
+ arm_idlect1_mask &= ~(1 << iclk->idlect_shift);
+}
+
+static __u16 verify_ckctl_value(__u16 newval)
+{
+ /* This function checks for following limitations set
+ * by the hardware (all conditions must be true):
+ * DSPMMU_CK == DSP_CK or DSPMMU_CK == DSP_CK/2
+ * ARM_CK >= TC_CK
+ * DSP_CK >= TC_CK
+ * DSPMMU_CK >= TC_CK
+ *
+ * In addition following rules are enforced:
+ * LCD_CK <= TC_CK
+ * ARMPER_CK <= TC_CK
+ *
+ * However, maximum frequencies are not checked for!
+ */
+ __u8 per_exp;
+ __u8 lcd_exp;
+ __u8 arm_exp;
+ __u8 dsp_exp;
+ __u8 tc_exp;
+ __u8 dspmmu_exp;
+
+ per_exp = (newval >> CKCTL_PERDIV_OFFSET) & 3;
+ lcd_exp = (newval >> CKCTL_LCDDIV_OFFSET) & 3;
+ arm_exp = (newval >> CKCTL_ARMDIV_OFFSET) & 3;
+ dsp_exp = (newval >> CKCTL_DSPDIV_OFFSET) & 3;
+ tc_exp = (newval >> CKCTL_TCDIV_OFFSET) & 3;
+ dspmmu_exp = (newval >> CKCTL_DSPMMUDIV_OFFSET) & 3;
+
+ if (dspmmu_exp < dsp_exp)
+ dspmmu_exp = dsp_exp;
+ if (dspmmu_exp > dsp_exp+1)
+ dspmmu_exp = dsp_exp+1;
+ if (tc_exp < arm_exp)
+ tc_exp = arm_exp;
+ if (tc_exp < dspmmu_exp)
+ tc_exp = dspmmu_exp;
+ if (tc_exp > lcd_exp)
+ lcd_exp = tc_exp;
+ if (tc_exp > per_exp)
+ per_exp = tc_exp;
+
+ newval &= 0xf000;
+ newval |= per_exp << CKCTL_PERDIV_OFFSET;
+ newval |= lcd_exp << CKCTL_LCDDIV_OFFSET;
+ newval |= arm_exp << CKCTL_ARMDIV_OFFSET;
+ newval |= dsp_exp << CKCTL_DSPDIV_OFFSET;
+ newval |= tc_exp << CKCTL_TCDIV_OFFSET;
+ newval |= dspmmu_exp << CKCTL_DSPMMUDIV_OFFSET;
+
+ return newval;
+}
+
+static int calc_dsor_exp(struct clk *clk, unsigned long rate)
+{
+ /* Note: If target frequency is too low, this function will return 4,
+ * which is invalid value. Caller must check for this value and act
+ * accordingly.
+ *
+ * Note: This function does not check for following limitations set
+ * by the hardware (all conditions must be true):
+ * DSPMMU_CK == DSP_CK or DSPMMU_CK == DSP_CK/2
+ * ARM_CK >= TC_CK
+ * DSP_CK >= TC_CK
+ * DSPMMU_CK >= TC_CK
+ */
+ unsigned long realrate;
+ struct clk * parent;
+ unsigned dsor_exp;
+
+ parent = clk->parent;
+ if (unlikely(parent == NULL))
+ return -EIO;
+
+ realrate = parent->rate;
+ for (dsor_exp=0; dsor_exp<4; dsor_exp++) {
+ if (realrate <= rate)
+ break;
+
+ realrate /= 2;
+ }
+
+ return dsor_exp;
+}
+
+unsigned long omap1_ckctl_recalc(struct clk *clk)
+{
+ /* Calculate divisor encoded as 2-bit exponent */
+ int dsor = 1 << (3 & (omap_readw(ARM_CKCTL) >> clk->rate_offset));
+
+ return clk->parent->rate / dsor;
+}
+
+unsigned long omap1_ckctl_recalc_dsp_domain(struct clk *clk)
+{
+ int dsor;
+
+ /* Calculate divisor encoded as 2-bit exponent
+ *
+ * The clock control bits are in DSP domain,
+ * so api_ck is needed for access.
+ * Note that DSP_CKCTL virt addr = phys addr, so
+ * we must use __raw_readw() instead of omap_readw().
+ */
+ omap1_clk_enable(api_ck_p);
+ dsor = 1 << (3 & (__raw_readw(DSP_CKCTL) >> clk->rate_offset));
+ omap1_clk_disable(api_ck_p);
+
+ return clk->parent->rate / dsor;
+}
+
+/* MPU virtual clock functions */
+int omap1_select_table_rate(struct clk *clk, unsigned long rate)
+{
+ /* Find the highest supported frequency <= rate and switch to it */
+ struct mpu_rate * ptr;
+ unsigned long ref_rate;
+
+ ref_rate = ck_ref_p->rate;
+
+ for (ptr = omap1_rate_table; ptr->rate; ptr++) {
+ if (!(ptr->flags & cpu_mask))
+ continue;
+
+ if (ptr->xtal != ref_rate)
+ continue;
+
+ /* Can check only after xtal frequency check */
+ if (ptr->rate <= rate)
+ break;
+ }
+
+ if (!ptr->rate)
+ return -EINVAL;
+
+ /*
+ * In most cases we should not need to reprogram DPLL.
+ * Reprogramming the DPLL is tricky, it must be done from SRAM.
+ */
+ omap_sram_reprogram_clock(ptr->dpllctl_val, ptr->ckctl_val);
+
+ /* XXX Do we need to recalculate the tree below DPLL1 at this point? */
+ ck_dpll1_p->rate = ptr->pll_rate;
+
+ return 0;
+}
+
+int omap1_clk_set_rate_dsp_domain(struct clk *clk, unsigned long rate)
+{
+ int dsor_exp;
+ u16 regval;
+
+ dsor_exp = calc_dsor_exp(clk, rate);
+ if (dsor_exp > 3)
+ dsor_exp = -EINVAL;
+ if (dsor_exp < 0)
+ return dsor_exp;
+
+ regval = __raw_readw(DSP_CKCTL);
+ regval &= ~(3 << clk->rate_offset);
+ regval |= dsor_exp << clk->rate_offset;
+ __raw_writew(regval, DSP_CKCTL);
+ clk->rate = clk->parent->rate / (1 << dsor_exp);
+
+ return 0;
+}
+
+long omap1_clk_round_rate_ckctl_arm(struct clk *clk, unsigned long rate)
+{
+ int dsor_exp = calc_dsor_exp(clk, rate);
+ if (dsor_exp < 0)
+ return dsor_exp;
+ if (dsor_exp > 3)
+ dsor_exp = 3;
+ return clk->parent->rate / (1 << dsor_exp);
+}
+
+int omap1_clk_set_rate_ckctl_arm(struct clk *clk, unsigned long rate)
+{
+ int dsor_exp;
+ u16 regval;
+
+ dsor_exp = calc_dsor_exp(clk, rate);
+ if (dsor_exp > 3)
+ dsor_exp = -EINVAL;
+ if (dsor_exp < 0)
+ return dsor_exp;
+
+ regval = omap_readw(ARM_CKCTL);
+ regval &= ~(3 << clk->rate_offset);
+ regval |= dsor_exp << clk->rate_offset;
+ regval = verify_ckctl_value(regval);
+ omap_writew(regval, ARM_CKCTL);
+ clk->rate = clk->parent->rate / (1 << dsor_exp);
+ return 0;
+}
+
+long omap1_round_to_table_rate(struct clk *clk, unsigned long rate)
+{
+ /* Find the highest supported frequency <= rate */
+ struct mpu_rate * ptr;
+ long highest_rate;
+ unsigned long ref_rate;
+
+ ref_rate = ck_ref_p->rate;
+
+ highest_rate = -EINVAL;
+
+ for (ptr = omap1_rate_table; ptr->rate; ptr++) {
+ if (!(ptr->flags & cpu_mask))
+ continue;
+
+ if (ptr->xtal != ref_rate)
+ continue;
+
+ highest_rate = ptr->rate;
+
+ /* Can check only after xtal frequency check */
+ if (ptr->rate <= rate)
+ break;
+ }
+
+ return highest_rate;
+}
+
+static unsigned calc_ext_dsor(unsigned long rate)
+{
+ unsigned dsor;
+
+ /* MCLK and BCLK divisor selection is not linear:
+ * freq = 96MHz / dsor
+ *
+ * RATIO_SEL range: dsor <-> RATIO_SEL
+ * 0..6: (RATIO_SEL+2) <-> (dsor-2)
+ * 6..48: (8+(RATIO_SEL-6)*2) <-> ((dsor-8)/2+6)
+ * Minimum dsor is 2 and maximum is 96. Odd divisors starting from 9
+ * can not be used.
+ */
+ for (dsor = 2; dsor < 96; ++dsor) {
+ if ((dsor & 1) && dsor > 8)
+ continue;
+ if (rate >= 96000000 / dsor)
+ break;
+ }
+ return dsor;
+}
+
+/* XXX Only needed on 1510 */
+int omap1_set_uart_rate(struct clk *clk, unsigned long rate)
+{
+ unsigned int val;
+
+ val = __raw_readl(clk->enable_reg);
+ if (rate == 12000000)
+ val &= ~(1 << clk->enable_bit);
+ else if (rate == 48000000)
+ val |= (1 << clk->enable_bit);
+ else
+ return -EINVAL;
+ __raw_writel(val, clk->enable_reg);
+ clk->rate = rate;
+
+ return 0;
+}
+
+/* External clock (MCLK & BCLK) functions */
+int omap1_set_ext_clk_rate(struct clk *clk, unsigned long rate)
+{
+ unsigned dsor;
+ __u16 ratio_bits;
+
+ dsor = calc_ext_dsor(rate);
+ clk->rate = 96000000 / dsor;
+ if (dsor > 8)
+ ratio_bits = ((dsor - 8) / 2 + 6) << 2;
+ else
+ ratio_bits = (dsor - 2) << 2;
+
+ ratio_bits |= __raw_readw(clk->enable_reg) & ~0xfd;
+ __raw_writew(ratio_bits, clk->enable_reg);
+
+ return 0;
+}
+
+int omap1_set_sossi_rate(struct clk *clk, unsigned long rate)
+{
+ u32 l;
+ int div;
+ unsigned long p_rate;
+
+ p_rate = clk->parent->rate;
+ /* Round towards slower frequency */
+ div = (p_rate + rate - 1) / rate;
+ div--;
+ if (div < 0 || div > 7)
+ return -EINVAL;
+
+ l = omap_readl(MOD_CONF_CTRL_1);
+ l &= ~(7 << 17);
+ l |= div << 17;
+ omap_writel(l, MOD_CONF_CTRL_1);
+
+ clk->rate = p_rate / (div + 1);
+
+ return 0;
+}
+
+long omap1_round_ext_clk_rate(struct clk *clk, unsigned long rate)
+{
+ return 96000000 / calc_ext_dsor(rate);
+}
+
+void omap1_init_ext_clk(struct clk *clk)
+{
+ unsigned dsor;
+ __u16 ratio_bits;
+
+ /* Determine current rate and ensure clock is based on 96MHz APLL */
+ ratio_bits = __raw_readw(clk->enable_reg) & ~1;
+ __raw_writew(ratio_bits, clk->enable_reg);
+
+ ratio_bits = (ratio_bits & 0xfc) >> 2;
+ if (ratio_bits > 6)
+ dsor = (ratio_bits - 6) * 2 + 8;
+ else
+ dsor = ratio_bits + 2;
+
+ clk-> rate = 96000000 / dsor;
+}
+
+int omap1_clk_enable(struct clk *clk)
+{
+ int ret = 0;
+
+ if (clk->usecount++ == 0) {
+ if (clk->parent) {
+ ret = omap1_clk_enable(clk->parent);
+ if (ret)
+ goto err;
+
+ if (clk->flags & CLOCK_NO_IDLE_PARENT)
+ omap1_clk_deny_idle(clk->parent);
+ }
+
+ ret = clk->ops->enable(clk);
+ if (ret) {
+ if (clk->parent)
+ omap1_clk_disable(clk->parent);
+ goto err;
+ }
+ }
+ return ret;
+
+err:
+ clk->usecount--;
+ return ret;
+}
+
+void omap1_clk_disable(struct clk *clk)
+{
+ if (clk->usecount > 0 && !(--clk->usecount)) {
+ clk->ops->disable(clk);
+ if (likely(clk->parent)) {
+ omap1_clk_disable(clk->parent);
+ if (clk->flags & CLOCK_NO_IDLE_PARENT)
+ omap1_clk_allow_idle(clk->parent);
+ }
+ }
+}
+
+static int omap1_clk_enable_generic(struct clk *clk)
+{
+ __u16 regval16;
+ __u32 regval32;
+
+ if (unlikely(clk->enable_reg == NULL)) {
+ printk(KERN_ERR "clock.c: Enable for %s without enable code\n",
+ clk->name);
+ return -EINVAL;
+ }
+
+ if (clk->flags & ENABLE_REG_32BIT) {
+ regval32 = __raw_readl(clk->enable_reg);
+ regval32 |= (1 << clk->enable_bit);
+ __raw_writel(regval32, clk->enable_reg);
+ } else {
+ regval16 = __raw_readw(clk->enable_reg);
+ regval16 |= (1 << clk->enable_bit);
+ __raw_writew(regval16, clk->enable_reg);
+ }
+
+ return 0;
+}
+
+static void omap1_clk_disable_generic(struct clk *clk)
+{
+ __u16 regval16;
+ __u32 regval32;
+
+ if (clk->enable_reg == NULL)
+ return;
+
+ if (clk->flags & ENABLE_REG_32BIT) {
+ regval32 = __raw_readl(clk->enable_reg);
+ regval32 &= ~(1 << clk->enable_bit);
+ __raw_writel(regval32, clk->enable_reg);
+ } else {
+ regval16 = __raw_readw(clk->enable_reg);
+ regval16 &= ~(1 << clk->enable_bit);
+ __raw_writew(regval16, clk->enable_reg);
+ }
+}
+
+const struct clkops clkops_generic = {
+ .enable = omap1_clk_enable_generic,
+ .disable = omap1_clk_disable_generic,
+};
+
+static int omap1_clk_enable_dsp_domain(struct clk *clk)
+{
+ int retval;
+
+ retval = omap1_clk_enable(api_ck_p);
+ if (!retval) {
+ retval = omap1_clk_enable_generic(clk);
+ omap1_clk_disable(api_ck_p);
+ }
+
+ return retval;
+}
+
+static void omap1_clk_disable_dsp_domain(struct clk *clk)
+{
+ if (omap1_clk_enable(api_ck_p) == 0) {
+ omap1_clk_disable_generic(clk);
+ omap1_clk_disable(api_ck_p);
+ }
+}
+
+const struct clkops clkops_dspck = {
+ .enable = omap1_clk_enable_dsp_domain,
+ .disable = omap1_clk_disable_dsp_domain,
+};
+
+/* XXX SYSC register handling does not belong in the clock framework */
+static int omap1_clk_enable_uart_functional_16xx(struct clk *clk)
+{
+ int ret;
+ struct uart_clk *uclk;
+
+ ret = omap1_clk_enable_generic(clk);
+ if (ret == 0) {
+ /* Set smart idle acknowledgement mode */
+ uclk = (struct uart_clk *)clk;
+ omap_writeb((omap_readb(uclk->sysc_addr) & ~0x10) | 8,
+ uclk->sysc_addr);
+ }
+
+ return ret;
+}
+
+/* XXX SYSC register handling does not belong in the clock framework */
+static void omap1_clk_disable_uart_functional_16xx(struct clk *clk)
+{
+ struct uart_clk *uclk;
+
+ /* Set force idle acknowledgement mode */
+ uclk = (struct uart_clk *)clk;
+ omap_writeb((omap_readb(uclk->sysc_addr) & ~0x18), uclk->sysc_addr);
+
+ omap1_clk_disable_generic(clk);
+}
+
+/* XXX SYSC register handling does not belong in the clock framework */
+const struct clkops clkops_uart_16xx = {
+ .enable = omap1_clk_enable_uart_functional_16xx,
+ .disable = omap1_clk_disable_uart_functional_16xx,
+};
+
+long omap1_clk_round_rate(struct clk *clk, unsigned long rate)
+{
+ if (clk->round_rate != NULL)
+ return clk->round_rate(clk, rate);
+
+ return clk->rate;
+}
+
+int omap1_clk_set_rate(struct clk *clk, unsigned long rate)
+{
+ int ret = -EINVAL;
+
+ if (clk->set_rate)
+ ret = clk->set_rate(clk, rate);
+ return ret;
+}
+
+/*
+ * Omap1 clock reset and init functions
+ */
+
+#ifdef CONFIG_OMAP_RESET_CLOCKS
+
+void omap1_clk_disable_unused(struct clk *clk)
+{
+ __u32 regval32;
+
+ /* Clocks in the DSP domain need api_ck. Just assume bootloader
+ * has not enabled any DSP clocks */
+ if (clk->enable_reg == DSP_IDLECT2) {
+ pr_info("Skipping reset check for DSP domain clock \"%s\"\n",
+ clk->name);
+ return;
+ }
+
+ /* Is the clock already disabled? */
+ if (clk->flags & ENABLE_REG_32BIT)
+ regval32 = __raw_readl(clk->enable_reg);
+ else
+ regval32 = __raw_readw(clk->enable_reg);
+
+ if ((regval32 & (1 << clk->enable_bit)) == 0)
+ return;
+
+ printk(KERN_INFO "Disabling unused clock \"%s\"... ", clk->name);
+ clk->ops->disable(clk);
+ printk(" done\n");
+}
+
+#endif
+
+
+int clk_enable(struct clk *clk)
+{
+ unsigned long flags;
+ int ret;
+
+ if (clk == NULL || IS_ERR(clk))
+ return -EINVAL;
+
+ spin_lock_irqsave(&clockfw_lock, flags);
+ ret = omap1_clk_enable(clk);
+ spin_unlock_irqrestore(&clockfw_lock, flags);
+
+ return ret;
+}
+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);
+ if (clk->usecount == 0) {
+ pr_err("Trying disable clock %s with 0 usecount\n",
+ clk->name);
+ WARN_ON(1);
+ goto out;
+ }
+
+ omap1_clk_disable(clk);
+
+out:
+ spin_unlock_irqrestore(&clockfw_lock, flags);
+}
+EXPORT_SYMBOL(clk_disable);
+
+unsigned long clk_get_rate(struct clk *clk)
+{
+ unsigned long flags;
+ unsigned long ret;
+
+ if (clk == NULL || IS_ERR(clk))
+ return 0;
+
+ spin_lock_irqsave(&clockfw_lock, flags);
+ ret = clk->rate;
+ spin_unlock_irqrestore(&clockfw_lock, flags);
+
+ return ret;
+}
+EXPORT_SYMBOL(clk_get_rate);
+
+/*
+ * Optional clock functions defined in include/linux/clk.h
+ */
+
+long clk_round_rate(struct clk *clk, unsigned long rate)
+{
+ unsigned long flags;
+ long ret;
+
+ if (clk == NULL || IS_ERR(clk))
+ return 0;
+
+ spin_lock_irqsave(&clockfw_lock, flags);
+ ret = omap1_clk_round_rate(clk, rate);
+ spin_unlock_irqrestore(&clockfw_lock, flags);
+
+ return ret;
+}
+EXPORT_SYMBOL(clk_round_rate);
+
+int clk_set_rate(struct clk *clk, unsigned long rate)
+{
+ unsigned long flags;
+ int ret = -EINVAL;
+
+ if (clk == NULL || IS_ERR(clk))
+ return ret;
+
+ spin_lock_irqsave(&clockfw_lock, flags);
+ ret = omap1_clk_set_rate(clk, rate);
+ if (ret == 0)
+ 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)
+{
+ WARN_ONCE(1, "clk_set_parent() not implemented for OMAP1\n");
+
+ return -EINVAL;
+}
+EXPORT_SYMBOL(clk_set_parent);
+
+struct clk *clk_get_parent(struct clk *clk)
+{
+ return clk->parent;
+}
+EXPORT_SYMBOL(clk_get_parent);
+
+/*
+ * OMAP specific clock functions shared between omap1 and omap2
+ */
+
+int __initdata mpurate;
+
+/*
+ * By default we use the rate set by the bootloader.
+ * You can override this with mpurate= cmdline option.
+ */
+static int __init omap_clk_setup(char *str)
+{
+ get_option(&str, &mpurate);
+
+ if (!mpurate)
+ return 1;
+
+ if (mpurate < 1000)
+ mpurate *= 1000000;
+
+ return 1;
+}
+__setup("mpurate=", omap_clk_setup);
+
+/* Used for clocks that always have same value as the parent clock */
+unsigned long followparent_recalc(struct clk *clk)
+{
+ return clk->parent->rate;
+}
+
+/*
+ * Used for clocks that have the same value as the parent clock,
+ * divided by some factor
+ */
+unsigned long omap_fixed_divisor_recalc(struct clk *clk)
+{
+ WARN_ON(!clk->fixed_div);
+
+ return clk->parent->rate / clk->fixed_div;
+}
+
+void clk_reparent(struct clk *child, struct clk *parent)
+{
+ list_del_init(&child->sibling);
+ if (parent)
+ list_add(&child->sibling, &parent->children);
+ child->parent = parent;
+
+ /* now do the debugfs renaming to reattach the child
+ to the proper parent */
+}
+
+/* Propagate rate to children */
+void propagate_rate(struct clk *tclk)
+{
+ struct clk *clkp;
+
+ list_for_each_entry(clkp, &tclk->children, sibling) {
+ if (clkp->recalc)
+ clkp->rate = clkp->recalc(clkp);
+ propagate_rate(clkp);
+ }
+}
+
+static LIST_HEAD(root_clks);
+
+/**
+ * recalculate_root_clocks - recalculate and propagate all root clocks
+ *
+ * Recalculates all root clocks (clocks with no parent), which if the
+ * clock's .recalc is set correctly, should also propagate their rates.
+ * Called at init.
+ */
+void recalculate_root_clocks(void)
+{
+ struct clk *clkp;
+
+ list_for_each_entry(clkp, &root_clks, sibling) {
+ if (clkp->recalc)
+ clkp->rate = clkp->recalc(clkp);
+ propagate_rate(clkp);
+ }
+}
+
+/**
+ * clk_preinit - initialize any fields in the struct clk before clk init
+ * @clk: struct clk * to initialize
+ *
+ * Initialize any struct clk fields needed before normal clk initialization
+ * can run. No return value.
+ */
+void clk_preinit(struct clk *clk)
+{
+ INIT_LIST_HEAD(&clk->children);
+}
+
+int clk_register(struct clk *clk)
+{
+ if (clk == NULL || IS_ERR(clk))
+ return -EINVAL;
+
+ /*
+ * trap out already registered clocks
+ */
+ if (clk->node.next || clk->node.prev)
+ return 0;
+
+ mutex_lock(&clocks_mutex);
+ if (clk->parent)
+ list_add(&clk->sibling, &clk->parent->children);
+ else
+ list_add(&clk->sibling, &root_clks);
+
+ list_add(&clk->node, &clocks);
+ if (clk->init)
+ clk->init(clk);
+ mutex_unlock(&clocks_mutex);
+
+ 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->sibling);
+ list_del(&clk->node);
+ mutex_unlock(&clocks_mutex);
+}
+EXPORT_SYMBOL(clk_unregister);
+
+void clk_enable_init_clocks(void)
+{
+ struct clk *clkp;
+
+ list_for_each_entry(clkp, &clocks, node)
+ if (clkp->flags & ENABLE_ON_INIT)
+ clk_enable(clkp);
+}
+
+/**
+ * omap_clk_get_by_name - locate OMAP struct clk by its name
+ * @name: name of the struct clk to locate
+ *
+ * Locate an OMAP struct clk by its name. Assumes that struct clk
+ * names are unique. Returns NULL if not found or a pointer to the
+ * struct clk if found.
+ */
+struct clk *omap_clk_get_by_name(const char *name)
+{
+ struct clk *c;
+ struct clk *ret = NULL;
+
+ mutex_lock(&clocks_mutex);
+
+ list_for_each_entry(c, &clocks, node) {
+ if (!strcmp(c->name, name)) {
+ ret = c;
+ break;
+ }
+ }
+
+ mutex_unlock(&clocks_mutex);
+
+ return ret;
+}
+
+int omap_clk_enable_autoidle_all(void)
+{
+ struct clk *c;
+ unsigned long flags;
+
+ spin_lock_irqsave(&clockfw_lock, flags);
+
+ list_for_each_entry(c, &clocks, node)
+ if (c->ops->allow_idle)
+ c->ops->allow_idle(c);
+
+ spin_unlock_irqrestore(&clockfw_lock, flags);
+
+ return 0;
+}
+
+int omap_clk_disable_autoidle_all(void)
+{
+ struct clk *c;
+ unsigned long flags;
+
+ spin_lock_irqsave(&clockfw_lock, flags);
+
+ list_for_each_entry(c, &clocks, node)
+ if (c->ops->deny_idle)
+ c->ops->deny_idle(c);
+
+ spin_unlock_irqrestore(&clockfw_lock, flags);
+
+ return 0;
+}
+
+/*
+ * Low level helpers
+ */
+static int clkll_enable_null(struct clk *clk)
+{
+ return 0;
+}
+
+static void clkll_disable_null(struct clk *clk)
+{
+}
+
+const struct clkops clkops_null = {
+ .enable = clkll_enable_null,
+ .disable = clkll_disable_null,
+};
+
+/*
+ * Dummy clock
+ *
+ * Used for clock aliases that are needed on some OMAPs, but not others
+ */
+struct clk dummy_ck = {
+ .name = "dummy",
+ .ops = &clkops_null,
+};
+
+/*
+ *
+ */
+
+#ifdef CONFIG_OMAP_RESET_CLOCKS
+/*
+ * Disable any unused clocks left on by the bootloader
+ */
+static int __init clk_disable_unused(void)
+{
+ struct clk *ck;
+ unsigned long flags;
+
+ pr_info("clock: disabling unused clocks to save power\n");
+
+ spin_lock_irqsave(&clockfw_lock, flags);
+ list_for_each_entry(ck, &clocks, node) {
+ if (ck->ops == &clkops_null)
+ continue;
+
+ if (ck->usecount > 0 || !ck->enable_reg)
+ continue;
+
+ omap1_clk_disable_unused(ck);
+ }
+ spin_unlock_irqrestore(&clockfw_lock, flags);
+
+ return 0;
+}
+late_initcall(clk_disable_unused);
+late_initcall(omap_clk_enable_autoidle_all);
+#endif
+
+#if defined(CONFIG_PM_DEBUG) && defined(CONFIG_DEBUG_FS)
+/*
+ * debugfs support to trace clock tree hierarchy and attributes
+ */
+
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+
+static struct dentry *clk_debugfs_root;
+
+static int clk_dbg_show_summary(struct seq_file *s, void *unused)
+{
+ struct clk *c;
+ struct clk *pa;
+
+ mutex_lock(&clocks_mutex);
+ seq_printf(s, "%-30s %-30s %-10s %s\n",
+ "clock-name", "parent-name", "rate", "use-count");
+
+ list_for_each_entry(c, &clocks, node) {
+ pa = c->parent;
+ seq_printf(s, "%-30s %-30s %-10lu %d\n",
+ c->name, pa ? pa->name : "none", c->rate,
+ c->usecount);
+ }
+ mutex_unlock(&clocks_mutex);
+
+ return 0;
+}
+
+static int clk_dbg_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, clk_dbg_show_summary, inode->i_private);
+}
+
+static const struct file_operations debug_clock_fops = {
+ .open = clk_dbg_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static int clk_debugfs_register_one(struct clk *c)
+{
+ int err;
+ struct dentry *d;
+ struct clk *pa = c->parent;
+
+ d = debugfs_create_dir(c->name, pa ? pa->dent : clk_debugfs_root);
+ if (!d)
+ return -ENOMEM;
+ c->dent = d;
+
+ d = debugfs_create_u8("usecount", S_IRUGO, c->dent, (u8 *)&c->usecount);
+ if (!d) {
+ err = -ENOMEM;
+ goto err_out;
+ }
+ d = debugfs_create_u32("rate", S_IRUGO, c->dent, (u32 *)&c->rate);
+ if (!d) {
+ err = -ENOMEM;
+ goto err_out;
+ }
+ d = debugfs_create_x32("flags", S_IRUGO, c->dent, (u32 *)&c->flags);
+ if (!d) {
+ err = -ENOMEM;
+ goto err_out;
+ }
+ return 0;
+
+err_out:
+ debugfs_remove_recursive(c->dent);
+ return err;
+}
+
+static int clk_debugfs_register(struct clk *c)
+{
+ int err;
+ struct clk *pa = c->parent;
+
+ if (pa && !pa->dent) {
+ err = clk_debugfs_register(pa);
+ if (err)
+ return err;
+ }
+
+ if (!c->dent) {
+ err = clk_debugfs_register_one(c);
+ if (err)
+ return err;
+ }
+ return 0;
+}
+
+static int __init clk_debugfs_init(void)
+{
+ struct clk *c;
+ struct dentry *d;
+ int err;
+
+ d = debugfs_create_dir("clock", NULL);
+ if (!d)
+ return -ENOMEM;
+ clk_debugfs_root = d;
+
+ list_for_each_entry(c, &clocks, node) {
+ err = clk_debugfs_register(c);
+ if (err)
+ goto err_out;
+ }
+
+ d = debugfs_create_file("summary", S_IRUGO,
+ d, NULL, &debug_clock_fops);
+ if (!d)
+ return -ENOMEM;
+
+ return 0;
+err_out:
+ debugfs_remove_recursive(clk_debugfs_root);
+ return err;
+}
+late_initcall(clk_debugfs_init);
+
+#endif /* defined(CONFIG_PM_DEBUG) && defined(CONFIG_DEBUG_FS) */