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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/dma_timer.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/dma_timer.c')
-rw-r--r--arch/m68k/platform/coldfire/dma_timer.c84
1 files changed, 84 insertions, 0 deletions
diff --git a/arch/m68k/platform/coldfire/dma_timer.c b/arch/m68k/platform/coldfire/dma_timer.c
new file mode 100644
index 000000000000..a5f562823d7a
--- /dev/null
+++ b/arch/m68k/platform/coldfire/dma_timer.c
@@ -0,0 +1,84 @@
+/*
+ * dma_timer.c -- Freescale ColdFire DMA Timer.
+ *
+ * Copyright (C) 2007, Benedikt Spranger <b.spranger@linutronix.de>
+ * Copyright (C) 2008. Sebastian Siewior, Linutronix
+ *
+ */
+
+#include <linux/clocksource.h>
+#include <linux/io.h>
+
+#include <asm/machdep.h>
+#include <asm/coldfire.h>
+#include <asm/mcfpit.h>
+#include <asm/mcfsim.h>
+
+#define DMA_TIMER_0 (0x00)
+#define DMA_TIMER_1 (0x40)
+#define DMA_TIMER_2 (0x80)
+#define DMA_TIMER_3 (0xc0)
+
+#define DTMR0 (MCF_IPSBAR + DMA_TIMER_0 + 0x400)
+#define DTXMR0 (MCF_IPSBAR + DMA_TIMER_0 + 0x402)
+#define DTER0 (MCF_IPSBAR + DMA_TIMER_0 + 0x403)
+#define DTRR0 (MCF_IPSBAR + DMA_TIMER_0 + 0x404)
+#define DTCR0 (MCF_IPSBAR + DMA_TIMER_0 + 0x408)
+#define DTCN0 (MCF_IPSBAR + DMA_TIMER_0 + 0x40c)
+
+#define DMA_FREQ ((MCF_CLK / 2) / 16)
+
+/* DTMR */
+#define DMA_DTMR_RESTART (1 << 3)
+#define DMA_DTMR_CLK_DIV_1 (1 << 1)
+#define DMA_DTMR_CLK_DIV_16 (2 << 1)
+#define DMA_DTMR_ENABLE (1 << 0)
+
+static cycle_t cf_dt_get_cycles(struct clocksource *cs)
+{
+ return __raw_readl(DTCN0);
+}
+
+static struct clocksource clocksource_cf_dt = {
+ .name = "coldfire_dma_timer",
+ .rating = 200,
+ .read = cf_dt_get_cycles,
+ .mask = CLOCKSOURCE_MASK(32),
+ .shift = 20,
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+static int __init init_cf_dt_clocksource(void)
+{
+ /*
+ * We setup DMA timer 0 in free run mode. This incrementing counter is
+ * used as a highly precious clock source. With MCF_CLOCK = 150 MHz we
+ * get a ~213 ns resolution and the 32bit register will overflow almost
+ * every 15 minutes.
+ */
+ __raw_writeb(0x00, DTXMR0);
+ __raw_writeb(0x00, DTER0);
+ __raw_writel(0x00000000, DTRR0);
+ __raw_writew(DMA_DTMR_CLK_DIV_16 | DMA_DTMR_ENABLE, DTMR0);
+ clocksource_cf_dt.mult = clocksource_hz2mult(DMA_FREQ,
+ clocksource_cf_dt.shift);
+ return clocksource_register(&clocksource_cf_dt);
+}
+
+arch_initcall(init_cf_dt_clocksource);
+
+#define CYC2NS_SCALE_FACTOR 10 /* 2^10, carefully chosen */
+#define CYC2NS_SCALE ((1000000 << CYC2NS_SCALE_FACTOR) / (DMA_FREQ / 1000))
+
+static unsigned long long cycles2ns(unsigned long cycl)
+{
+ return (unsigned long long) ((unsigned long long)cycl *
+ CYC2NS_SCALE) >> CYC2NS_SCALE_FACTOR;
+}
+
+unsigned long long sched_clock(void)
+{
+ unsigned long cycl = __raw_readl(DTCN0);
+
+ return cycles2ns(cycl);
+}