[PATCH 7/7] ARM: tegra: clock: Disable clocks left on by bootloader
From: Colin Cross <hidden>
Date: 2011-02-22 02:41:27
Also in:
linux-tegra, lkml
Subsystem:
arm port, the rest · Maintainers:
Russell King, Linus Torvalds
Iterates through all clocks, disabling any for which the refcount is 0 but the clock init detected the bootloader left the clock on. Can be disabled with command line tegra_clock.disable_boot_clocks=N Signed-off-by: Colin Cross <redacted> --- arch/arm/mach-tegra/clock.c | 44 +++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 44 insertions(+), 0 deletions(-)
diff --git a/arch/arm/mach-tegra/clock.c b/arch/arm/mach-tegra/clock.c
index e028320..6d686ff 100644
--- a/arch/arm/mach-tegra/clock.c
+++ b/arch/arm/mach-tegra/clock.c@@ -33,6 +33,9 @@ #include "board.h" #include "clock.h" +#undef MODULE_PARAM_PREFIX +#define MODULE_PARAM_PREFIX "tegra_clock." + /* * Locking: *
@@ -416,6 +419,47 @@ void tegra_sdmmc_tap_delay(struct clk *c, int delay) spin_unlock_irqrestore(&c->spinlock, flags); } +static bool tegra_disable_boot_clocks = true; +module_param_named(disable_boot_clocks, tegra_disable_boot_clocks, bool, + S_IRUGO | S_IWUSR | S_IWGRP); + +/* + * Iterate through all clocks, disabling any for which the refcount is 0 + * but the clock init detected the bootloader left the clock on. + */ +static int __init tegra_init_disable_boot_clocks(void) +{ + struct clk *c; + + mutex_lock(&clock_list_lock); + + list_for_each_entry(c, &clocks, node) { + spin_lock_irq(&c->spinlock); + + if (c->refcnt == 0 && c->state == ON && + c->ops && c->ops->disable) { + pr_warn_once("%s clocks left on by bootloader:\n", + tegra_disable_boot_clocks ? + "Disabling" : + "Prevented disabling"); + + pr_warn(" %s\n", c->name); + + if (tegra_disable_boot_clocks) { + c->ops->disable(c); + c->state = OFF; + } + } + + spin_unlock_irq(&c->spinlock); + } + + mutex_unlock(&clock_list_lock); + + return 0; +} +late_initcall(tegra_init_disable_boot_clocks); + #ifdef CONFIG_DEBUG_FS static int __clk_lock_all_spinlocks(void)
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1.7.3.1