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author | Linus Torvalds <torvalds@linux-foundation.org> | 2010-10-25 07:44:27 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2010-10-25 07:44:27 -0700 |
commit | 4b37ba90f49d4157ac5628f8d730d3505f176724 (patch) | |
tree | fdb3d04426f7b72ee86b1f06be746624494493c5 /arch/m68knommu/platform/coldfire/sltimers.c | |
parent | 229aebb873e29726b91e076161649cf45154b0bf (diff) | |
parent | 55f411de484a0136a77d050e877578a60bc2e094 (diff) | |
download | op-kernel-dev-4b37ba90f49d4157ac5628f8d730d3505f176724.zip op-kernel-dev-4b37ba90f49d4157ac5628f8d730d3505f176724.tar.gz |
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu: (21 commits)
m68knommu: convert to using tracehook_report_syscall_*
m68knommu: some boards use fixed phy for FEC ethernet
m68knommu: support the external GPIO based interrupts of the 5272
m68knommu: mask of vector bits in exception word properly
m68knommu: change to new flag variables
m68knommu: Fix MCFUART_TXFIFOSIZE for m548x.
m68knommu: add basic mmu-less m548x support
m68knommu: .gitignore vmlinux.lds
m68knommu: stop using __do_IRQ
m68knommu: rename PT_OFF_VECTOR to PT_OFF_FORMATVEC.
m68knommu: add support for Coldfire 547x/548x interrupt controller
m68k{nommu}: Remove unused DEFINE's from asm-offsets.c
m68knommu: whitespace cleanup in 68328/entry.S
m68knommu: Document supported chips in intc-2.c and intc-simr.c.
m68knommu: fix strace support for 68328/68360
m68knommu: fix default starting date
arch/m68knommu: Removing dead 68328_SERIAL_UART2 config option
arch/m68knommu: Removing dead RAM_{16,32}_MB config option
arch/m68knommu: Removing dead M68KFPU_EMU config option
arch/m68knommu: Removing dead RELOCATE config option
...
Diffstat (limited to 'arch/m68knommu/platform/coldfire/sltimers.c')
-rw-r--r-- | arch/m68knommu/platform/coldfire/sltimers.c | 145 |
1 files changed, 145 insertions, 0 deletions
diff --git a/arch/m68knommu/platform/coldfire/sltimers.c b/arch/m68knommu/platform/coldfire/sltimers.c new file mode 100644 index 0000000..0a1b937 --- /dev/null +++ b/arch/m68knommu/platform/coldfire/sltimers.c @@ -0,0 +1,145 @@ +/***************************************************************************/ + +/* + * sltimers.c -- generic ColdFire slice timer support. + * + * Copyright (C) 2009-2010, Philippe De Muyter <phdm@macqel.be> + * based on + * timers.c -- generic ColdFire hardware timer support. + * Copyright (C) 1999-2008, Greg Ungerer <gerg@snapgear.com> + */ + +/***************************************************************************/ + +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/sched.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/profile.h> +#include <linux/clocksource.h> +#include <asm/io.h> +#include <asm/traps.h> +#include <asm/machdep.h> +#include <asm/coldfire.h> +#include <asm/mcfslt.h> +#include <asm/mcfsim.h> + +/***************************************************************************/ + +#ifdef CONFIG_HIGHPROFILE + +/* + * By default use Slice Timer 1 as the profiler clock timer. + */ +#define PA(a) (MCF_MBAR + MCFSLT_TIMER1 + (a)) + +/* + * Choose a reasonably fast profile timer. Make it an odd value to + * try and get good coverage of kernel operations. + */ +#define PROFILEHZ 1013 + +irqreturn_t mcfslt_profile_tick(int irq, void *dummy) +{ + /* Reset Slice Timer 1 */ + __raw_writel(MCFSLT_SSR_BE | MCFSLT_SSR_TE, PA(MCFSLT_SSR)); + if (current->pid) + profile_tick(CPU_PROFILING); + return IRQ_HANDLED; +} + +static struct irqaction mcfslt_profile_irq = { + .name = "profile timer", + .flags = IRQF_DISABLED | IRQF_TIMER, + .handler = mcfslt_profile_tick, +}; + +void mcfslt_profile_init(void) +{ + printk(KERN_INFO "PROFILE: lodging TIMER 1 @ %dHz as profile timer\n", + PROFILEHZ); + + setup_irq(MCF_IRQ_PROFILER, &mcfslt_profile_irq); + + /* Set up TIMER 2 as high speed profile clock */ + __raw_writel(MCF_BUSCLK / PROFILEHZ - 1, PA(MCFSLT_STCNT)); + __raw_writel(MCFSLT_SCR_RUN | MCFSLT_SCR_IEN | MCFSLT_SCR_TEN, + PA(MCFSLT_SCR)); + +} + +#endif /* CONFIG_HIGHPROFILE */ + +/***************************************************************************/ + +/* + * By default use Slice Timer 0 as the system clock timer. + */ +#define TA(a) (MCF_MBAR + MCFSLT_TIMER0 + (a)) + +static u32 mcfslt_cycles_per_jiffy; +static u32 mcfslt_cnt; + +static irqreturn_t mcfslt_tick(int irq, void *dummy) +{ + /* Reset Slice Timer 0 */ + __raw_writel(MCFSLT_SSR_BE | MCFSLT_SSR_TE, TA(MCFSLT_SSR)); + mcfslt_cnt += mcfslt_cycles_per_jiffy; + return arch_timer_interrupt(irq, dummy); +} + +static struct irqaction mcfslt_timer_irq = { + .name = "timer", + .flags = IRQF_DISABLED | IRQF_TIMER, + .handler = mcfslt_tick, +}; + +static cycle_t mcfslt_read_clk(struct clocksource *cs) +{ + unsigned long flags; + u32 cycles; + u16 scnt; + + local_irq_save(flags); + scnt = __raw_readl(TA(MCFSLT_SCNT)); + cycles = mcfslt_cnt; + local_irq_restore(flags); + + /* substract because slice timers count down */ + return cycles - scnt; +} + +static struct clocksource mcfslt_clk = { + .name = "slt", + .rating = 250, + .read = mcfslt_read_clk, + .shift = 20, + .mask = CLOCKSOURCE_MASK(32), + .flags = CLOCK_SOURCE_IS_CONTINUOUS, +}; + +void hw_timer_init(void) +{ + mcfslt_cycles_per_jiffy = MCF_BUSCLK / HZ; + /* + * The coldfire slice timer (SLT) runs from STCNT to 0 included, + * then STCNT again and so on. It counts thus actually + * STCNT + 1 steps for 1 tick, not STCNT. So if you want + * n cycles, initialize STCNT with n - 1. + */ + __raw_writel(mcfslt_cycles_per_jiffy - 1, TA(MCFSLT_STCNT)); + __raw_writel(MCFSLT_SCR_RUN | MCFSLT_SCR_IEN | MCFSLT_SCR_TEN, + TA(MCFSLT_SCR)); + /* initialize mcfslt_cnt knowing that slice timers count down */ + mcfslt_cnt = mcfslt_cycles_per_jiffy; + + setup_irq(MCF_IRQ_TIMER, &mcfslt_timer_irq); + + mcfslt_clk.mult = clocksource_hz2mult(MCF_BUSCLK, mcfslt_clk.shift); + clocksource_register(&mcfslt_clk); + +#ifdef CONFIG_HIGHPROFILE + mcfslt_profile_init(); +#endif +} |