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authorGreg Ungerer <gerg@uclinux.org>2011-03-22 06:39:27 +0300
committerGreg Ungerer <gerg@uclinux.org>2011-03-25 07:05:13 +0300
commit66d857b08b8c3ed5c72c361f863cce77d2a978d7 (patch)
tree47222d86f4d78dc0da31baf64188bd2e4b38ac1e /arch/m68k/platform/coldfire/timers.c
parentd39dd11c3e6a7af5c20bfac40594db36cf270f42 (diff)
downloadlinux-66d857b08b8c3ed5c72c361f863cce77d2a978d7.tar.xz
m68k: merge m68k and m68knommu arch directories
There is a lot of common code that could be shared between the m68k and m68knommu arch branches. It makes sense to merge the two branches into a single directory structure so that we can more easily share that common code. This is a brute force merge, based on a script from Stephen King <sfking@fdwdc.com>, which was originally written by Arnd Bergmann <arnd@arndb.de>. > The script was inspired by the script Sam Ravnborg used to merge the > includes from m68knommu. For those files common to both arches but > differing in content, the m68k version of the file is renamed to > <file>_mm.<ext> and the m68knommu version of the file is moved into the > corresponding m68k directory and renamed <file>_no.<ext> and a small > wrapper file <file>.<ext> is used to select between the two version. Files > that are common to both but don't differ are removed from the m68knommu > tree and files and directories that are unique to the m68knommu tree are > moved to the m68k tree. Finally, the arch/m68knommu tree is removed. > > To select between the the versions of the files, the wrapper uses > > #ifdef CONFIG_MMU > #include <file>_mm.<ext> > #else > #include <file>_no.<ext> > #endif On top of this file merge I have done a simplistic merge of m68k and m68knommu Kconfig, which primarily attempts to keep existing options and menus in place. Other than a handful of options being moved it produces identical .config outputs on m68k and m68knommu targets I tested it on. With this in place there is now quite a bit of scope for merge cleanups in future patches. Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Diffstat (limited to 'arch/m68k/platform/coldfire/timers.c')
-rw-r--r--arch/m68k/platform/coldfire/timers.c174
1 files changed, 174 insertions, 0 deletions
diff --git a/arch/m68k/platform/coldfire/timers.c b/arch/m68k/platform/coldfire/timers.c
new file mode 100644
index 000000000000..60242f65fea9
--- /dev/null
+++ b/arch/m68k/platform/coldfire/timers.c
@@ -0,0 +1,174 @@
+/***************************************************************************/
+
+/*
+ * 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/mcftimer.h>
+#include <asm/mcfsim.h>
+
+/***************************************************************************/
+
+/*
+ * By default use timer1 as the system clock timer.
+ */
+#define FREQ (MCF_BUSCLK / 16)
+#define TA(a) (MCFTIMER_BASE1 + (a))
+
+/*
+ * These provide the underlying interrupt vector support.
+ * Unfortunately it is a little different on each ColdFire.
+ */
+void coldfire_profile_init(void);
+
+#if defined(CONFIG_M532x)
+#define __raw_readtrr __raw_readl
+#define __raw_writetrr __raw_writel
+#else
+#define __raw_readtrr __raw_readw
+#define __raw_writetrr __raw_writew
+#endif
+
+static u32 mcftmr_cycles_per_jiffy;
+static u32 mcftmr_cnt;
+
+/***************************************************************************/
+
+static irqreturn_t mcftmr_tick(int irq, void *dummy)
+{
+ /* Reset the ColdFire timer */
+ __raw_writeb(MCFTIMER_TER_CAP | MCFTIMER_TER_REF, TA(MCFTIMER_TER));
+
+ mcftmr_cnt += mcftmr_cycles_per_jiffy;
+ return arch_timer_interrupt(irq, dummy);
+}
+
+/***************************************************************************/
+
+static struct irqaction mcftmr_timer_irq = {
+ .name = "timer",
+ .flags = IRQF_DISABLED | IRQF_TIMER,
+ .handler = mcftmr_tick,
+};
+
+/***************************************************************************/
+
+static cycle_t mcftmr_read_clk(struct clocksource *cs)
+{
+ unsigned long flags;
+ u32 cycles;
+ u16 tcn;
+
+ local_irq_save(flags);
+ tcn = __raw_readw(TA(MCFTIMER_TCN));
+ cycles = mcftmr_cnt;
+ local_irq_restore(flags);
+
+ return cycles + tcn;
+}
+
+/***************************************************************************/
+
+static struct clocksource mcftmr_clk = {
+ .name = "tmr",
+ .rating = 250,
+ .read = mcftmr_read_clk,
+ .shift = 20,
+ .mask = CLOCKSOURCE_MASK(32),
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+/***************************************************************************/
+
+void hw_timer_init(void)
+{
+ __raw_writew(MCFTIMER_TMR_DISABLE, TA(MCFTIMER_TMR));
+ mcftmr_cycles_per_jiffy = FREQ / HZ;
+ /*
+ * The coldfire timer runs from 0 to TRR included, then 0
+ * again and so on. It counts thus actually TRR + 1 steps
+ * for 1 tick, not TRR. So if you want n cycles,
+ * initialize TRR with n - 1.
+ */
+ __raw_writetrr(mcftmr_cycles_per_jiffy - 1, TA(MCFTIMER_TRR));
+ __raw_writew(MCFTIMER_TMR_ENORI | MCFTIMER_TMR_CLK16 |
+ MCFTIMER_TMR_RESTART | MCFTIMER_TMR_ENABLE, TA(MCFTIMER_TMR));
+
+ mcftmr_clk.mult = clocksource_hz2mult(FREQ, mcftmr_clk.shift);
+ clocksource_register(&mcftmr_clk);
+
+ setup_irq(MCF_IRQ_TIMER, &mcftmr_timer_irq);
+
+#ifdef CONFIG_HIGHPROFILE
+ coldfire_profile_init();
+#endif
+}
+
+/***************************************************************************/
+#ifdef CONFIG_HIGHPROFILE
+/***************************************************************************/
+
+/*
+ * By default use timer2 as the profiler clock timer.
+ */
+#define PA(a) (MCFTIMER_BASE2 + (a))
+
+/*
+ * Choose a reasonably fast profile timer. Make it an odd value to
+ * try and get good coverage of kernel operations.
+ */
+#define PROFILEHZ 1013
+
+/*
+ * Use the other timer to provide high accuracy profiling info.
+ */
+irqreturn_t coldfire_profile_tick(int irq, void *dummy)
+{
+ /* Reset ColdFire timer2 */
+ __raw_writeb(MCFTIMER_TER_CAP | MCFTIMER_TER_REF, PA(MCFTIMER_TER));
+ if (current->pid)
+ profile_tick(CPU_PROFILING);
+ return IRQ_HANDLED;
+}
+
+/***************************************************************************/
+
+static struct irqaction coldfire_profile_irq = {
+ .name = "profile timer",
+ .flags = IRQF_DISABLED | IRQF_TIMER,
+ .handler = coldfire_profile_tick,
+};
+
+void coldfire_profile_init(void)
+{
+ printk(KERN_INFO "PROFILE: lodging TIMER2 @ %dHz as profile timer\n",
+ PROFILEHZ);
+
+ /* Set up TIMER 2 as high speed profile clock */
+ __raw_writew(MCFTIMER_TMR_DISABLE, PA(MCFTIMER_TMR));
+
+ __raw_writetrr(((MCF_BUSCLK / 16) / PROFILEHZ), PA(MCFTIMER_TRR));
+ __raw_writew(MCFTIMER_TMR_ENORI | MCFTIMER_TMR_CLK16 |
+ MCFTIMER_TMR_RESTART | MCFTIMER_TMR_ENABLE, PA(MCFTIMER_TMR));
+
+ setup_irq(MCF_IRQ_PROFILER, &coldfire_profile_irq);
+}
+
+/***************************************************************************/
+#endif /* CONFIG_HIGHPROFILE */
+/***************************************************************************/