Give each clock its own lock, and remove all lock traversals from parent to child clocks to prevent AB-BA deadlocks. This brings the locking in line with the common struct clk patches and should make conversion simple. Signed-off-by: Colin Cross <ccross@xxxxxxxxxxx> --- arch/arm/mach-tegra/clock.c | 370 ++++++++++++++++++++------------ arch/arm/mach-tegra/clock.h | 13 +- arch/arm/mach-tegra/include/mach/clk.h | 1 + arch/arm/mach-tegra/tegra2_clocks.c | 119 ++++++++--- 4 files changed, 327 insertions(+), 176 deletions(-) diff --git a/arch/arm/mach-tegra/clock.c b/arch/arm/mach-tegra/clock.c index a1193f9..34a1f8d 100644 --- a/arch/arm/mach-tegra/clock.c +++ b/arch/arm/mach-tegra/clock.c @@ -18,83 +18,116 @@ #include <linux/kernel.h> #include <linux/clk.h> -#include <linux/list.h> +#include <linux/clkdev.h> +#include <linux/debugfs.h> +#include <linux/delay.h> #include <linux/init.h> +#include <linux/list.h> #include <linux/module.h> -#include <linux/debugfs.h> -#include <linux/slab.h> +#include <linux/sched.h> #include <linux/seq_file.h> -#include <linux/clkdev.h> +#include <linux/slab.h> + +#include <mach/clk.h> #include "board.h" #include "clock.h" +/* + * Locking: + * + * Each struct clk has a spinlock. + * + * To avoid AB-BA locking problems, locks must always be traversed from child + * clock to parent clock. For example, when enabling a clock, the clock's lock + * is taken, and then clk_enable is called on the parent, which take's the + * parent clock's lock. There is one exceptions to this ordering: When dumping + * the clock tree through debugfs. In this case, clk_lock_all is called, + * which attemps to iterate through the entire list of clocks and take every + * clock lock. If any call to spin_trylock fails, all locked clocks are + * unlocked, and the process is retried. When all the locks are held, + * the only clock operation that can be called is clk_get_rate_all_locked. + * + * Within a single clock, no clock operation can call another clock operation + * on itself, except for clk_get_rate_locked. Any clock operation can call + * any other clock operation on any of it's possible parents. + * + * An additional mutex, clock_list_lock, is used to protect the list of all + * clocks. + * + * The clock operations must lock internally to protect against + * read-modify-write on registers that are shared by multiple clocks + */ +static DEFINE_MUTEX(clock_list_lock); static LIST_HEAD(clocks); -static DEFINE_SPINLOCK(clock_lock); struct clk *tegra_get_clock_by_name(const char *name) { struct clk *c; struct clk *ret = NULL; - unsigned long flags; - spin_lock_irqsave(&clock_lock, flags); + mutex_lock(&clock_list_lock); list_for_each_entry(c, &clocks, node) { if (strcmp(c->name, name) == 0) { ret = c; break; } } - spin_unlock_irqrestore(&clock_lock, flags); + mutex_unlock(&clock_list_lock); return ret; } -static void clk_recalculate_rate(struct clk *c) +/* Must be called with c->spinlock held */ +static unsigned long clk_predict_rate_from_parent(struct clk *c, struct clk *p) { u64 rate; - if (!c->parent) - return; - - rate = c->parent->rate; + rate = clk_get_rate(p); if (c->mul != 0 && c->div != 0) { - rate = rate * c->mul; + rate *= c->mul; do_div(rate, c->div); } - if (rate > c->max_rate) - pr_warn("clocks: Set clock %s to rate %llu, max is %lu\n", - c->name, rate, c->max_rate); - - c->rate = rate; + return rate; } -int clk_reparent(struct clk *c, struct clk *parent) +/* Must be called with c->spinlock held */ +unsigned long clk_get_rate_locked(struct clk *c) { - c->parent = parent; - list_del(&c->sibling); - list_add_tail(&c->sibling, &parent->children); - return 0; -} + unsigned long rate; -static void propagate_rate(struct clk *c) -{ - struct clk *clkp; + if (c->parent) + rate = clk_predict_rate_from_parent(c, c->parent); + else + rate = c->rate; - list_for_each_entry(clkp, &c->children, sibling) { - clk_recalculate_rate(clkp); - propagate_rate(clkp); - } + return rate; } -void clk_init(struct clk *c) +unsigned long clk_get_rate(struct clk *c) { unsigned long flags; + unsigned long rate; - spin_lock_irqsave(&clock_lock, flags); + spin_lock_irqsave(&c->spinlock, flags); + + rate = clk_get_rate_locked(c); + + spin_unlock_irqrestore(&c->spinlock, flags); + + return rate; +} +EXPORT_SYMBOL(clk_get_rate); + +int clk_reparent(struct clk *c, struct clk *parent) +{ + c->parent = parent; + return 0; +} - INIT_LIST_HEAD(&c->children); - INIT_LIST_HEAD(&c->sibling); +void clk_init(struct clk *c) +{ + spin_lock_init(&c->spinlock); if (c->ops && c->ops->init) c->ops->init(c); @@ -108,33 +141,31 @@ void clk_init(struct clk *c) c->state = ON; } - clk_recalculate_rate(c); - + mutex_lock(&clock_list_lock); list_add(&c->node, &clocks); - - if (c->parent) - list_add_tail(&c->sibling, &c->parent->children); - - spin_unlock_irqrestore(&clock_lock, flags); + mutex_unlock(&clock_list_lock); } -int clk_enable_locked(struct clk *c) +int clk_enable(struct clk *c) { - int ret; + int ret = 0; + unsigned long flags; + + spin_lock_irqsave(&c->spinlock, flags); if (c->refcnt == 0) { if (c->parent) { - ret = clk_enable_locked(c->parent); + ret = clk_enable(c->parent); if (ret) - return ret; + goto out; } if (c->ops && c->ops->enable) { ret = c->ops->enable(c); if (ret) { if (c->parent) - clk_disable_locked(c->parent); - return ret; + clk_disable(c->parent); + goto out; } c->state = ON; #ifdef CONFIG_DEBUG_FS @@ -143,27 +174,21 @@ int clk_enable_locked(struct clk *c) } } c->refcnt++; - - return 0; +out: + spin_unlock_irqrestore(&c->spinlock, flags); + return ret; } +EXPORT_SYMBOL(clk_enable); -int clk_enable(struct clk *c) +void clk_disable(struct clk *c) { - int ret; unsigned long flags; - spin_lock_irqsave(&clock_lock, flags); - ret = clk_enable_locked(c); - spin_unlock_irqrestore(&clock_lock, flags); - - return ret; -} -EXPORT_SYMBOL(clk_enable); + spin_lock_irqsave(&c->spinlock, flags); -void clk_disable_locked(struct clk *c) -{ if (c->refcnt == 0) { WARN(1, "Attempting to disable clock %s with refcnt 0", c->name); + spin_unlock_irqrestore(&c->spinlock, flags); return; } if (c->refcnt == 1) { @@ -171,49 +196,39 @@ void clk_disable_locked(struct clk *c) c->ops->disable(c); if (c->parent) - clk_disable_locked(c->parent); + clk_disable(c->parent); c->state = OFF; } c->refcnt--; -} -void clk_disable(struct clk *c) -{ - unsigned long flags; - - spin_lock_irqsave(&clock_lock, flags); - clk_disable_locked(c); - spin_unlock_irqrestore(&clock_lock, flags); + spin_unlock_irqrestore(&c->spinlock, flags); } EXPORT_SYMBOL(clk_disable); -int clk_set_parent_locked(struct clk *c, struct clk *parent) +int clk_set_parent(struct clk *c, struct clk *parent) { int ret; + unsigned long flags; + unsigned long new_rate; + unsigned long old_rate; - if (!c->ops || !c->ops->set_parent) - return -ENOSYS; - - ret = c->ops->set_parent(c, parent); - - if (ret) - return ret; + spin_lock_irqsave(&c->spinlock, flags); - clk_recalculate_rate(c); + if (!c->ops || !c->ops->set_parent) { + ret = -ENOSYS; + goto out; + } - propagate_rate(c); + new_rate = clk_predict_rate_from_parent(c, parent); + old_rate = clk_get_rate_locked(c); - return 0; -} + ret = c->ops->set_parent(c, parent); + if (ret) + goto out; -int clk_set_parent(struct clk *c, struct clk *parent) -{ - int ret; - unsigned long flags; - spin_lock_irqsave(&clock_lock, flags); - ret = clk_set_parent_locked(c, parent); - spin_unlock_irqrestore(&clock_lock, flags); +out: + spin_unlock_irqrestore(&c->spinlock, flags); return ret; } EXPORT_SYMBOL(clk_set_parent); @@ -224,64 +239,78 @@ struct clk *clk_get_parent(struct clk *c) } EXPORT_SYMBOL(clk_get_parent); -int clk_set_rate_locked(struct clk *c, unsigned long rate) +int clk_set_rate(struct clk *c, unsigned long rate) { - int ret; + int ret = 0; + unsigned long flags; + unsigned long old_rate; + + spin_lock_irqsave(&c->spinlock, flags); + + if (!c->ops || !c->ops->set_rate) { + ret = -ENOSYS; + goto out; + } + + old_rate = clk_get_rate_locked(c); if (rate > c->max_rate) rate = c->max_rate; - if (!c->ops || !c->ops->set_rate) - return -ENOSYS; - ret = c->ops->set_rate(c, rate); - if (ret) - return ret; - - clk_recalculate_rate(c); - - propagate_rate(c); - - return 0; -} - -int clk_set_rate(struct clk *c, unsigned long rate) -{ - int ret = 0; - unsigned long flags; - - spin_lock_irqsave(&clock_lock, flags); - ret = clk_set_rate_locked(c, rate); - spin_unlock_irqrestore(&clock_lock, flags); + goto out; +out: + spin_unlock_irqrestore(&c->spinlock, flags); return ret; } EXPORT_SYMBOL(clk_set_rate); -unsigned long clk_get_rate(struct clk *c) +/* Must be called with clocks lock and all indvidual clock locks held */ +unsigned long clk_get_rate_all_locked(struct clk *c) { - unsigned long flags; - unsigned long ret; - - spin_lock_irqsave(&clock_lock, flags); + u64 rate; + int mul = 1; + int div = 1; + struct clk *p = c; + + while (p) { + c = p; + if (c->mul != 0 && c->div != 0) { + mul *= c->mul; + div *= c->div; + } + p = c->parent; + } - ret = c->rate; + rate = c->rate; + rate *= mul; + do_div(rate, div); - spin_unlock_irqrestore(&clock_lock, flags); - return ret; + return rate; } -EXPORT_SYMBOL(clk_get_rate); long clk_round_rate(struct clk *c, unsigned long rate) { - if (!c->ops || !c->ops->round_rate) - return -ENOSYS; + unsigned long flags; + long ret; + + spin_lock_irqsave(&c->spinlock, flags); + + if (!c->ops || !c->ops->round_rate) { + ret = -ENOSYS; + goto out; + } if (rate > c->max_rate) rate = c->max_rate; - return c->ops->round_rate(c, rate); + ret = c->ops->round_rate(c, rate); + +out: + spin_unlock_irqrestore(&c->spinlock, flags); + return ret; } EXPORT_SYMBOL(clk_round_rate); @@ -374,9 +403,10 @@ int __init tegra_disable_boot_clocks(void) struct clk *c; - spin_lock_irqsave(&clock_lock, flags); + mutex_lock(&clock_list_lock); list_for_each_entry(c, &clocks, node) { + spin_lock_irqsave(&c->spinlock, flags); if (c->refcnt == 0 && c->state == ON && c->ops && c->ops->disable) { pr_warning("Disabling clock %s left on by bootloader\n", @@ -384,23 +414,85 @@ int __init tegra_disable_boot_clocks(void) c->ops->disable(c); c->state = OFF; } + spin_unlock_irqrestore(&c->spinlock, flags); } - spin_unlock_irqrestore(&clock_lock, flags); - + mutex_unlock(&clock_list_lock); return 0; } late_initcall(tegra_disable_boot_clocks); #endif #ifdef CONFIG_DEBUG_FS + +static int __clk_lock_all_spinlocks(void) +{ + struct clk *c; + + list_for_each_entry(c, &clocks, node) + if (!spin_trylock(&c->spinlock)) + goto unlock_spinlocks; + + return 0; + +unlock_spinlocks: + list_for_each_entry_continue_reverse(c, &clocks, node) + spin_unlock(&c->spinlock); + + return -EAGAIN; +} + +static void __clk_unlock_all_spinlocks(void) +{ + struct clk *c; + + list_for_each_entry_reverse(c, &clocks, node) + spin_unlock(&c->spinlock); +} + +/* + * This function retries until it can take all locks, and may take + * an arbitrarily long time to complete. + * Must be called with irqs enabled, returns with irqs disabled + * Must be called with clock_list_lock held + */ +static void clk_lock_all(void) +{ + int ret; +retry: + local_irq_disable(); + + ret = __clk_lock_all_spinlocks(); + if (ret) + goto failed_spinlocks; + + /* All locks taken successfully, return */ + return; + +failed_spinlocks: + local_irq_enable(); + yield(); + goto retry; +} + +/* + * Unlocks all clocks after a clk_lock_all + * Must be called with irqs disabled, returns with irqs enabled + * Must be called with clock_list_lock held + */ +static void clk_unlock_all(void) +{ + __clk_unlock_all_spinlocks(); + + local_irq_enable(); +} + static struct dentry *clk_debugfs_root; static void clock_tree_show_one(struct seq_file *s, struct clk *c, int level) { struct clk *child; - struct clk *safe; const char *state = "uninit"; char div[8] = {0}; @@ -431,8 +523,12 @@ static void clock_tree_show_one(struct seq_file *s, struct clk *c, int level) c->rate > c->max_rate ? '!' : ' ', !c->set ? '*' : ' ', 30 - level * 3, c->name, - state, c->refcnt, div, c->rate); - list_for_each_entry_safe(child, safe, &c->children, sibling) { + state, c->refcnt, div, clk_get_rate_all_locked(c)); + + list_for_each_entry(child, &clocks, node) { + if (child->parent != c) + continue; + clock_tree_show_one(s, child, level + 1); } } @@ -440,14 +536,20 @@ static void clock_tree_show_one(struct seq_file *s, struct clk *c, int level) static int clock_tree_show(struct seq_file *s, void *data) { struct clk *c; - unsigned long flags; seq_printf(s, " clock state ref div rate\n"); seq_printf(s, "--------------------------------------------------------------\n"); - spin_lock_irqsave(&clock_lock, flags); + + mutex_lock(&clock_list_lock); + + clk_lock_all(); + list_for_each_entry(c, &clocks, node) if (c->parent == NULL) clock_tree_show_one(s, c, 0); - spin_unlock_irqrestore(&clock_lock, flags); + + clk_unlock_all(); + + mutex_unlock(&clock_list_lock); return 0; } diff --git a/arch/arm/mach-tegra/clock.h b/arch/arm/mach-tegra/clock.h index 20f0ce6..dd5c029 100644 --- a/arch/arm/mach-tegra/clock.h +++ b/arch/arm/mach-tegra/clock.h @@ -20,8 +20,9 @@ #ifndef __MACH_TEGRA_CLOCK_H #define __MACH_TEGRA_CLOCK_H -#include <linux/list.h> #include <linux/clkdev.h> +#include <linux/list.h> +#include <linux/spinlock.h> #define DIV_BUS (1 << 0) #define DIV_U71 (1 << 1) @@ -75,8 +76,6 @@ enum clk_state { struct clk { /* node for master clocks list */ struct list_head node; /* node for list of all clocks */ - struct list_head children; /* list of children */ - struct list_head sibling; /* node for children */ struct clk_lookup lookup; #ifdef CONFIG_DEBUG_FS @@ -122,8 +121,9 @@ struct clk { struct clk *backup; } cpu; } u; -}; + spinlock_t spinlock; +}; struct clk_duplicate { const char *name; @@ -143,11 +143,8 @@ void tegra2_periph_reset_assert(struct clk *c); void clk_init(struct clk *clk); struct clk *tegra_get_clock_by_name(const char *name); unsigned long clk_measure_input_freq(void); -void clk_disable_locked(struct clk *c); -int clk_enable_locked(struct clk *c); -int clk_set_parent_locked(struct clk *c, struct clk *parent); -int clk_set_rate_locked(struct clk *c, unsigned long rate); int clk_reparent(struct clk *c, struct clk *parent); void tegra_clk_init_from_table(struct tegra_clk_init_table *table); +unsigned long clk_get_rate_locked(struct clk *c); #endif diff --git a/arch/arm/mach-tegra/include/mach/clk.h b/arch/arm/mach-tegra/include/mach/clk.h index 6338652..fa7f9ca 100644 --- a/arch/arm/mach-tegra/include/mach/clk.h +++ b/arch/arm/mach-tegra/include/mach/clk.h @@ -25,4 +25,5 @@ struct clk; void tegra_periph_reset_deassert(struct clk *c); void tegra_periph_reset_assert(struct clk *c); +unsigned long clk_get_rate_all_locked(struct clk *c); #endif diff --git a/arch/arm/mach-tegra/tegra2_clocks.c b/arch/arm/mach-tegra/tegra2_clocks.c index f03c712..ab013b1 100644 --- a/arch/arm/mach-tegra/tegra2_clocks.c +++ b/arch/arm/mach-tegra/tegra2_clocks.c @@ -23,8 +23,8 @@ #include <linux/spinlock.h> #include <linux/delay.h> #include <linux/io.h> -#include <linux/hrtimer.h> #include <linux/clkdev.h> +#include <linux/clk.h> #include <mach/iomap.h> #include <mach/suspend.h> @@ -147,6 +147,13 @@ static void __iomem *reg_clk_base = IO_ADDRESS(TEGRA_CLK_RESET_BASE); static void __iomem *reg_pmc_base = IO_ADDRESS(TEGRA_PMC_BASE); +/* + * Some clocks share a register with other clocks. Any clock op that + * non-atomically modifies a register used by another clock must lock + * clock_register_lock first. + */ +static DEFINE_SPINLOCK(clock_register_lock); + #define clk_writel(value, reg) \ __raw_writel(value, (u32)reg_clk_base + (reg)) #define clk_readl(reg) \ @@ -330,12 +337,12 @@ static int tegra2_super_clk_set_parent(struct clk *c, struct clk *p) val |= sel->value << shift; if (c->refcnt) - clk_enable_locked(p); + clk_enable(p); clk_writel(val, c->reg); if (c->refcnt && c->parent) - clk_disable_locked(c->parent); + clk_disable(c->parent); clk_reparent(c, p); return 0; @@ -378,22 +385,22 @@ static void tegra2_cpu_clk_disable(struct clk *c) static int tegra2_cpu_clk_set_rate(struct clk *c, unsigned long rate) { int ret; - ret = clk_set_parent_locked(c->parent, c->u.cpu.backup); + ret = clk_set_parent(c->parent, c->u.cpu.backup); if (ret) { pr_err("Failed to switch cpu to clock %s\n", c->u.cpu.backup->name); return ret; } - if (rate == c->u.cpu.backup->rate) + if (rate == clk_get_rate(c->u.cpu.backup)) goto out; - ret = clk_set_rate_locked(c->u.cpu.main, rate); + ret = clk_set_rate(c->u.cpu.main, rate); if (ret) { pr_err("Failed to change cpu pll to %lu\n", rate); return ret; } - ret = clk_set_parent_locked(c->parent, c->u.cpu.main); + ret = clk_set_parent(c->parent, c->u.cpu.main); if (ret) { pr_err("Failed to switch cpu to clock %s\n", c->u.cpu.main->name); return ret; @@ -421,24 +428,45 @@ static void tegra2_bus_clk_init(struct clk *c) static int tegra2_bus_clk_enable(struct clk *c) { - u32 val = clk_readl(c->reg); + u32 val; + unsigned long flags; + + spin_lock_irqsave(&clock_register_lock, flags); + + val = clk_readl(c->reg); val &= ~(BUS_CLK_DISABLE << c->reg_shift); clk_writel(val, c->reg); + + spin_unlock_irqrestore(&clock_register_lock, flags); + return 0; } static void tegra2_bus_clk_disable(struct clk *c) { - u32 val = clk_readl(c->reg); + u32 val; + unsigned long flags; + + spin_lock_irqsave(&clock_register_lock, flags); + + val = clk_readl(c->reg); val |= BUS_CLK_DISABLE << c->reg_shift; clk_writel(val, c->reg); + + spin_unlock_irqrestore(&clock_register_lock, flags); } static int tegra2_bus_clk_set_rate(struct clk *c, unsigned long rate) { - u32 val = clk_readl(c->reg); - unsigned long parent_rate = c->parent->rate; + u32 val; + unsigned long parent_rate = clk_get_rate(c->parent); + unsigned long flags; + int ret = -EINVAL; int i; + + spin_lock_irqsave(&clock_register_lock, flags); + + val = clk_readl(c->reg); for (i = 1; i <= 4; i++) { if (rate == parent_rate / i) { val &= ~(BUS_CLK_DIV_MASK << c->reg_shift); @@ -446,10 +474,14 @@ static int tegra2_bus_clk_set_rate(struct clk *c, unsigned long rate) clk_writel(val, c->reg); c->div = i; c->mul = 1; - return 0; + ret = 0; + break; } } - return -EINVAL; + + spin_unlock_irqrestore(&clock_register_lock, flags); + + return ret; } static struct clk_ops tegra_bus_ops = { @@ -511,14 +543,15 @@ static void tegra2_blink_clk_disable(struct clk *c) static int tegra2_blink_clk_set_rate(struct clk *c, unsigned long rate) { - if (rate >= c->parent->rate) { + unsigned long parent_rate = clk_get_rate(c->parent); + if (rate >= parent_rate) { c->div = 1; pmc_writel(0, c->reg); } else { unsigned int on_off; u32 val; - on_off = DIV_ROUND_UP(c->parent->rate / 8, rate); + on_off = DIV_ROUND_UP(parent_rate / 8, rate); c->div = on_off * 8; val = (on_off & PMC_BLINK_TIMER_DATA_ON_MASK) << @@ -604,7 +637,7 @@ static int tegra2_pll_clk_set_rate(struct clk *c, unsigned long rate) pr_debug("%s: %s %lu\n", __func__, c->name, rate); - input_rate = c->parent->rate; + input_rate = clk_get_rate(c->parent); for (sel = c->u.pll.freq_table; sel->input_rate != 0; sel++) { if (sel->input_rate == input_rate && sel->output_rate == rate) { c->mul = sel->n; @@ -717,9 +750,11 @@ static int tegra2_pll_div_clk_enable(struct clk *c) { u32 val; u32 new_val; + unsigned long flags; pr_debug("%s: %s\n", __func__, c->name); if (c->flags & DIV_U71) { + spin_lock_irqsave(&clock_register_lock, flags); val = clk_readl(c->reg); new_val = val >> c->reg_shift; new_val &= 0xFFFF; @@ -729,12 +764,15 @@ static int tegra2_pll_div_clk_enable(struct clk *c) val &= ~(0xFFFF << c->reg_shift); val |= new_val << c->reg_shift; clk_writel(val, c->reg); + spin_unlock_irqrestore(&clock_register_lock, flags); return 0; } else if (c->flags & DIV_2) { BUG_ON(!(c->flags & PLLD)); + spin_lock_irqsave(&clock_register_lock, flags); val = clk_readl(c->reg); val &= ~PLLD_MISC_DIV_RST; clk_writel(val, c->reg); + spin_unlock_irqrestore(&clock_register_lock, flags); return 0; } return -EINVAL; @@ -744,9 +782,11 @@ static void tegra2_pll_div_clk_disable(struct clk *c) { u32 val; u32 new_val; + unsigned long flags; pr_debug("%s: %s\n", __func__, c->name); if (c->flags & DIV_U71) { + spin_lock_irqsave(&clock_register_lock, flags); val = clk_readl(c->reg); new_val = val >> c->reg_shift; new_val &= 0xFFFF; @@ -756,11 +796,14 @@ static void tegra2_pll_div_clk_disable(struct clk *c) val &= ~(0xFFFF << c->reg_shift); val |= new_val << c->reg_shift; clk_writel(val, c->reg); + spin_unlock_irqrestore(&clock_register_lock, flags); } else if (c->flags & DIV_2) { BUG_ON(!(c->flags & PLLD)); + spin_lock_irqsave(&clock_register_lock, flags); val = clk_readl(c->reg); val |= PLLD_MISC_DIV_RST; clk_writel(val, c->reg); + spin_unlock_irqrestore(&clock_register_lock, flags); } } @@ -769,10 +812,14 @@ static int tegra2_pll_div_clk_set_rate(struct clk *c, unsigned long rate) u32 val; u32 new_val; int divider_u71; + unsigned long parent_rate = clk_get_rate(c->parent); + unsigned long flags; + pr_debug("%s: %s %lu\n", __func__, c->name, rate); if (c->flags & DIV_U71) { - divider_u71 = clk_div71_get_divider(c->parent->rate, rate); + divider_u71 = clk_div71_get_divider(parent_rate, rate); if (divider_u71 >= 0) { + spin_lock_irqsave(&clock_register_lock, flags); val = clk_readl(c->reg); new_val = val >> c->reg_shift; new_val &= 0xFFFF; @@ -786,10 +833,11 @@ static int tegra2_pll_div_clk_set_rate(struct clk *c, unsigned long rate) clk_writel(val, c->reg); c->div = divider_u71 + 2; c->mul = 2; + spin_unlock_irqrestore(&clock_register_lock, flags); return 0; } } else if (c->flags & DIV_2) { - if (c->parent->rate == rate * 2) + if (parent_rate == rate * 2) return 0; } return -EINVAL; @@ -798,15 +846,16 @@ static int tegra2_pll_div_clk_set_rate(struct clk *c, unsigned long rate) static long tegra2_pll_div_clk_round_rate(struct clk *c, unsigned long rate) { int divider; + unsigned long parent_rate = clk_get_rate(c->parent); pr_debug("%s: %s %lu\n", __func__, c->name, rate); if (c->flags & DIV_U71) { - divider = clk_div71_get_divider(c->parent->rate, rate); + divider = clk_div71_get_divider(parent_rate, rate); if (divider < 0) return divider; - return c->parent->rate * 2 / (divider + 2); + return parent_rate * 2 / (divider + 2); } else if (c->flags & DIV_2) { - return c->parent->rate / 2; + return parent_rate / 2; } return -EINVAL; } @@ -912,12 +961,12 @@ static int tegra2_periph_clk_set_parent(struct clk *c, struct clk *p) val |= (sel->value) << PERIPH_CLK_SOURCE_SHIFT; if (c->refcnt) - clk_enable_locked(p); + clk_enable(p); clk_writel(val, c->reg); if (c->refcnt && c->parent) - clk_disable_locked(c->parent); + clk_disable(c->parent); clk_reparent(c, p); return 0; @@ -931,9 +980,10 @@ static int tegra2_periph_clk_set_rate(struct clk *c, unsigned long rate) { u32 val; int divider; - pr_debug("%s: %lu\n", __func__, rate); + unsigned long parent_rate = clk_get_rate(c->parent); + if (c->flags & DIV_U71) { - divider = clk_div71_get_divider(c->parent->rate, rate); + divider = clk_div71_get_divider(parent_rate, rate); if (divider >= 0) { val = clk_readl(c->reg); val &= ~PERIPH_CLK_SOURCE_DIVU71_MASK; @@ -944,7 +994,7 @@ static int tegra2_periph_clk_set_rate(struct clk *c, unsigned long rate) return 0; } } else if (c->flags & DIV_U16) { - divider = clk_div16_get_divider(c->parent->rate, rate); + divider = clk_div16_get_divider(parent_rate, rate); if (divider >= 0) { val = clk_readl(c->reg); val &= ~PERIPH_CLK_SOURCE_DIVU16_MASK; @@ -954,7 +1004,7 @@ static int tegra2_periph_clk_set_rate(struct clk *c, unsigned long rate) c->mul = 1; return 0; } - } else if (c->parent->rate <= rate) { + } else if (parent_rate <= rate) { c->div = 1; c->mul = 1; return 0; @@ -966,19 +1016,20 @@ static long tegra2_periph_clk_round_rate(struct clk *c, unsigned long rate) { int divider; + unsigned long parent_rate = clk_get_rate(c->parent); pr_debug("%s: %s %lu\n", __func__, c->name, rate); if (c->flags & DIV_U71) { - divider = clk_div71_get_divider(c->parent->rate, rate); + divider = clk_div71_get_divider(parent_rate, rate); if (divider < 0) return divider; - return c->parent->rate * 2 / (divider + 2); + return parent_rate * 2 / (divider + 2); } else if (c->flags & DIV_U16) { - divider = clk_div16_get_divider(c->parent->rate, rate); + divider = clk_div16_get_divider(parent_rate, rate); if (divider < 0) return divider; - return c->parent->rate / (divider + 1); + return parent_rate / (divider + 1); } return -EINVAL; } @@ -1006,7 +1057,7 @@ static void tegra2_clk_double_init(struct clk *c) static int tegra2_clk_double_set_rate(struct clk *c, unsigned long rate) { - if (rate != 2 * c->parent->rate) + if (rate != 2 * clk_get_rate(c->parent)) return -EINVAL; c->mul = 2; c->div = 1; @@ -1057,12 +1108,12 @@ static int tegra2_audio_sync_clk_set_parent(struct clk *c, struct clk *p) val |= sel->value; if (c->refcnt) - clk_enable_locked(p); + clk_enable(p); clk_writel(val, c->reg); if (c->refcnt && c->parent) - clk_disable_locked(c->parent); + clk_disable(c->parent); clk_reparent(c, p); return 0; -- 1.7.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html