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authorDan Williams <dan.j.williams@intel.com>2006-12-07 02:59:39 +0100
committerRussell King <rmk+kernel@arm.linux.org.uk>2006-12-07 18:20:21 +0100
commit285f5fa7e9a35e75d9022f9b036ed709721c5cdf (patch)
treed977aecd1a350e2c14086005b873141d8d829e12 /arch/arm/mach-iop13xx/time.c
parent[ARM] 3968/1: iop13xx: add iop13xx_defconfig (diff)
downloadlinux-285f5fa7e9a35e75d9022f9b036ed709721c5cdf.tar.xz
linux-285f5fa7e9a35e75d9022f9b036ed709721c5cdf.zip
[ARM] 3995/1: iop13xx: add iop13xx support
The iop348 processor integrates an Xscale (XSC3 512KB L2 Cache) core with a Serial Attached SCSI (SAS) controller, multi-ported DDR2 memory controller, 3 Application Direct Memory Access (DMA) controllers, a 133Mhz PCI-X interface, a x8 PCI-Express interface, and other peripherals to form a system-on-a-chip RAID subsystem engine. The iop342 processor replaces the SAS controller with a second Xscale core for dual core embedded applications. The iop341 processor is the single core version of iop342. This patch supports the two Intel customer reference platforms iq81340mc for external storage and iq81340sc for direct attach (HBA) development. The developer's manual is available here: ftp://download.intel.com/design/iio/docs/31503701.pdf Changelog: * removed virtual addresses from resource definitions * cleaned up some unnecessary #include's Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/mach-iop13xx/time.c')
-rw-r--r--arch/arm/mach-iop13xx/time.c102
1 files changed, 102 insertions, 0 deletions
diff --git a/arch/arm/mach-iop13xx/time.c b/arch/arm/mach-iop13xx/time.c
new file mode 100644
index 000000000000..8b21365f653f
--- /dev/null
+++ b/arch/arm/mach-iop13xx/time.c
@@ -0,0 +1,102 @@
+/*
+ * arch/arm/mach-iop13xx/time.c
+ *
+ * Timer code for IOP13xx (copied from IOP32x/IOP33x implementation)
+ *
+ * Author: Deepak Saxena <dsaxena@mvista.com>
+ *
+ * Copyright 2002-2003 MontaVista Software Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/time.h>
+#include <linux/init.h>
+#include <linux/timex.h>
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <asm/uaccess.h>
+#include <asm/mach/irq.h>
+#include <asm/mach/time.h>
+
+static unsigned long ticks_per_jiffy;
+static unsigned long ticks_per_usec;
+static unsigned long next_jiffy_time;
+
+static inline u32 read_tcr1(void)
+{
+ u32 val;
+ asm volatile("mrc p6, 0, %0, c3, c9, 0" : "=r" (val));
+ return val;
+}
+
+unsigned long iop13xx_gettimeoffset(void)
+{
+ unsigned long offset;
+ u32 cp_flags;
+
+ cp_flags = iop13xx_cp6_save();
+ offset = next_jiffy_time - read_tcr1();
+ iop13xx_cp6_restore(cp_flags);
+
+ return offset / ticks_per_usec;
+}
+
+static irqreturn_t
+iop13xx_timer_interrupt(int irq, void *dev_id)
+{
+ u32 cp_flags = iop13xx_cp6_save();
+
+ write_seqlock(&xtime_lock);
+
+ asm volatile("mcr p6, 0, %0, c6, c9, 0" : : "r" (1));
+
+ while ((signed long)(next_jiffy_time - read_tcr1())
+ >= ticks_per_jiffy) {
+ timer_tick();
+ next_jiffy_time -= ticks_per_jiffy;
+ }
+
+ write_sequnlock(&xtime_lock);
+
+ iop13xx_cp6_restore(cp_flags);
+
+ return IRQ_HANDLED;
+}
+
+static struct irqaction iop13xx_timer_irq = {
+ .name = "IOP13XX Timer Tick",
+ .handler = iop13xx_timer_interrupt,
+ .flags = IRQF_DISABLED | IRQF_TIMER,
+};
+
+void __init iop13xx_init_time(unsigned long tick_rate)
+{
+ u32 timer_ctl;
+ u32 cp_flags;
+
+ ticks_per_jiffy = (tick_rate + HZ/2) / HZ;
+ ticks_per_usec = tick_rate / 1000000;
+ next_jiffy_time = 0xffffffff;
+
+ timer_ctl = IOP13XX_TMR_EN | IOP13XX_TMR_PRIVILEGED |
+ IOP13XX_TMR_RELOAD | IOP13XX_TMR_RATIO_1_1;
+
+ /*
+ * We use timer 0 for our timer interrupt, and timer 1 as
+ * monotonic counter for tracking missed jiffies.
+ */
+ cp_flags = iop13xx_cp6_save();
+ asm volatile("mcr p6, 0, %0, c4, c9, 0" : : "r" (ticks_per_jiffy - 1));
+ asm volatile("mcr p6, 0, %0, c0, c9, 0" : : "r" (timer_ctl));
+ asm volatile("mcr p6, 0, %0, c5, c9, 0" : : "r" (0xffffffff));
+ asm volatile("mcr p6, 0, %0, c1, c9, 0" : : "r" (timer_ctl));
+ iop13xx_cp6_restore(cp_flags);
+
+ setup_irq(IRQ_IOP13XX_TIMER0, &iop13xx_timer_irq);
+}