diff options
author | Len Brown <len.brown@intel.com> | 2006-06-29 19:57:46 -0400 |
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committer | Len Brown <len.brown@intel.com> | 2006-06-29 19:57:46 -0400 |
commit | d120cfb544ed6161b9d32fb6c4648c471807ee6b (patch) | |
tree | 7757ad0198d8df76ff5c60f939a687687c41da00 /arch/arm/kernel/crunch.c | |
parent | 9dce0e950dbfab4148f35ac6f297d8638cdc63c4 (diff) | |
parent | bf7e8511088963078484132636839b59e25cf14f (diff) | |
download | linux-d120cfb544ed6161b9d32fb6c4648c471807ee6b.tar.bz2 |
merge linus into release branch
Conflicts:
drivers/acpi/acpi_memhotplug.c
Diffstat (limited to 'arch/arm/kernel/crunch.c')
-rw-r--r-- | arch/arm/kernel/crunch.c | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/arch/arm/kernel/crunch.c b/arch/arm/kernel/crunch.c new file mode 100644 index 000000000000..748175921f9b --- /dev/null +++ b/arch/arm/kernel/crunch.c @@ -0,0 +1,83 @@ +/* + * arch/arm/kernel/crunch.c + * Cirrus MaverickCrunch context switching and handling + * + * Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org> + * + * 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/module.h> +#include <linux/config.h> +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/signal.h> +#include <linux/sched.h> +#include <linux/init.h> +#include <asm/arch/ep93xx-regs.h> +#include <asm/thread_notify.h> +#include <asm/io.h> + +struct crunch_state *crunch_owner; + +void crunch_task_release(struct thread_info *thread) +{ + local_irq_disable(); + if (crunch_owner == &thread->crunchstate) + crunch_owner = NULL; + local_irq_enable(); +} + +static int crunch_enabled(u32 devcfg) +{ + return !!(devcfg & EP93XX_SYSCON_DEVICE_CONFIG_CRUNCH_ENABLE); +} + +static int crunch_do(struct notifier_block *self, unsigned long cmd, void *t) +{ + struct thread_info *thread = (struct thread_info *)t; + struct crunch_state *crunch_state; + u32 devcfg; + + crunch_state = &thread->crunchstate; + + switch (cmd) { + case THREAD_NOTIFY_FLUSH: + memset(crunch_state, 0, sizeof(*crunch_state)); + + /* + * FALLTHROUGH: Ensure we don't try to overwrite our newly + * initialised state information on the first fault. + */ + + case THREAD_NOTIFY_RELEASE: + crunch_task_release(thread); + break; + + case THREAD_NOTIFY_SWITCH: + devcfg = __raw_readl(EP93XX_SYSCON_DEVICE_CONFIG); + if (crunch_enabled(devcfg) || crunch_owner == crunch_state) { + devcfg ^= EP93XX_SYSCON_DEVICE_CONFIG_CRUNCH_ENABLE; + __raw_writel(0xaa, EP93XX_SYSCON_SWLOCK); + __raw_writel(devcfg, EP93XX_SYSCON_DEVICE_CONFIG); + } + break; + } + + return NOTIFY_DONE; +} + +static struct notifier_block crunch_notifier_block = { + .notifier_call = crunch_do, +}; + +static int __init crunch_init(void) +{ + thread_register_notifier(&crunch_notifier_block); + + return 0; +} + +late_initcall(crunch_init); |