[ARM] 3427/1: ARM: OMAP: 2/8 Update timers

Patch from Tony Lindgren

Update OMAP timers from linux-omap tree. The highlights of the
patch are:

- Move timer32k code from mach-omap1 to plat-omap and make it
  work also on omap24xx by Tony Lindgren
- Add support for dmtimer idle check for PM by Tuukka Tikkanen

Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

3 files changed, 353 insertions, 2 deletions

diff --git a/arch/arm/plat-omap/Kconfig b/arch/arm/plat-omap/Kconfig
index 0887bb2a2551..ec49495e651e 100644
--- a/arch/arm/plat-omap/Kconfig
+++ b/arch/arm/plat-omap/Kconfig
@@ -70,13 +70,13 @@ config OMAP_MPU_TIMER
 
 config OMAP_32K_TIMER
 	bool "Use 32KHz timer"
-	depends on ARCH_OMAP16XX
+	depends on ARCH_OMAP16XX || ARCH_OMAP24XX
 	help
 	  Select this option if you want to enable the OMAP 32KHz timer.
 	  This timer saves power compared to the OMAP_MPU_TIMER, and has
 	  support for no tick during idle. The 32KHz timer provides less
 	  intra-tick resolution than OMAP_MPU_TIMER. The 32KHz timer is
-	  currently only available for OMAP-16xx.
+	  currently only available for OMAP16XX and 24XX.
 
 endchoice
 
diff --git a/arch/arm/plat-omap/dmtimer.c b/arch/arm/plat-omap/dmtimer.c
index 38d7ebf87920..eba3cb52ad87 100644
--- a/arch/arm/plat-omap/dmtimer.c
+++ b/arch/arm/plat-omap/dmtimer.c
@@ -97,6 +97,32 @@ int omap_dm_timers_active(void)
 }
 
 
+/**
+ * omap_dm_timer_modify_idlect_mask - Check if any running timers use ARMXOR
+ * @inputmask: current value of idlect mask
+ */
+__u32 omap_dm_timer_modify_idlect_mask(__u32 inputmask)
+{
+	int n;
+
+	/* If ARMXOR cannot be idled this function call is unnecessary */
+	if (!(inputmask & (1 << 1)))
+		return inputmask;
+
+	/* If any active timer is using ARMXOR return modified mask */
+	for (n = 0; dm_timers[n].base; ++n)
+		if (omap_dm_timer_read_reg(&dm_timers[n], OMAP_TIMER_CTRL_REG)&
+		    OMAP_TIMER_CTRL_ST) {
+			if (((omap_readl(MOD_CONF_CTRL_1)>>(n*2)) & 0x03) == 0)
+				inputmask &= ~(1 << 1);
+			else
+				inputmask &= ~(1 << 2);
+		}
+
+	return inputmask;
+}
+
+
 void omap_dm_timer_set_source(struct omap_dm_timer *timer, int source)
 {
 	int n = (timer - dm_timers) << 1;
diff --git a/arch/arm/plat-omap/timer32k.c b/arch/arm/plat-omap/timer32k.c
new file mode 100644
index 000000000000..b2a943bf11ef
--- /dev/null
+++ b/arch/arm/plat-omap/timer32k.c
@@ -0,0 +1,325 @@
+/*
+ * linux/arch/arm/plat-omap/timer32k.c
+ *
+ * OMAP 32K Timer
+ *
+ * Copyright (C) 2004 - 2005 Nokia Corporation
+ * Partial timer rewrite and additional dynamic tick timer support by
+ * Tony Lindgen <tony@atomide.com> and
+ * Tuukka Tikkanen <tuukka.tikkanen@elektrobit.com>
+ *
+ * MPU timer code based on the older MPU timer code for OMAP
+ * Copyright (C) 2000 RidgeRun, Inc.
+ * Author: Greg Lonnon <glonnon@ridgerun.com>
+ *
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
+ * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * You should have received a copy of the  GNU General Public License along
+ * with this program; if not, write  to the Free Software Foundation, Inc.,
+ * 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/sched.h>
+#include <linux/spinlock.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+
+#include <asm/system.h>
+#include <asm/hardware.h>
+#include <asm/io.h>
+#include <asm/leds.h>
+#include <asm/irq.h>
+#include <asm/mach/irq.h>
+#include <asm/mach/time.h>
+
+struct sys_timer omap_timer;
+
+/*
+ * ---------------------------------------------------------------------------
+ * 32KHz OS timer
+ *
+ * This currently works only on 16xx, as 1510 does not have the continuous
+ * 32KHz synchronous timer. The 32KHz synchronous timer is used to keep track
+ * of time in addition to the 32KHz OS timer. Using only the 32KHz OS timer
+ * on 1510 would be possible, but the timer would not be as accurate as
+ * with the 32KHz synchronized timer.
+ * ---------------------------------------------------------------------------
+ */
+
+#if defined(CONFIG_ARCH_OMAP16XX)
+#define TIMER_32K_SYNCHRONIZED		0xfffbc410
+#elif defined(CONFIG_ARCH_OMAP24XX)
+#define TIMER_32K_SYNCHRONIZED		0x48004010
+#else
+#error OMAP 32KHz timer does not currently work on 15XX!
+#endif
+
+/* 16xx specific defines */
+#define OMAP1_32K_TIMER_BASE		0xfffb9000
+#define OMAP1_32K_TIMER_CR		0x08
+#define OMAP1_32K_TIMER_TVR		0x00
+#define OMAP1_32K_TIMER_TCR		0x04
+
+/* 24xx specific defines */
+#define OMAP2_GP_TIMER_BASE		0x48028000
+#define CM_CLKSEL_WKUP			0x48008440
+#define GP_TIMER_TIDR			0x00
+#define GP_TIMER_TISR			0x18
+#define GP_TIMER_TIER			0x1c
+#define GP_TIMER_TCLR			0x24
+#define GP_TIMER_TCRR			0x28
+#define GP_TIMER_TLDR			0x2c
+#define GP_TIMER_TTGR			0x30
+#define GP_TIMER_TSICR			0x40
+
+#define OMAP_32K_TICKS_PER_HZ		(32768 / HZ)
+
+/*
+ * TRM says 1 / HZ = ( TVR + 1) / 32768, so TRV = (32768 / HZ) - 1
+ * so with HZ = 128, TVR = 255.
+ */
+#define OMAP_32K_TIMER_TICK_PERIOD	((32768 / HZ) - 1)
+
+#define JIFFIES_TO_HW_TICKS(nr_jiffies, clock_rate)			\
+				(((nr_jiffies) * (clock_rate)) / HZ)
+
+static inline void omap_32k_timer_write(int val, int reg)
+{
+	if (cpu_class_is_omap1())
+		omap_writew(val, OMAP1_32K_TIMER_BASE + reg);
+
+	if (cpu_is_omap24xx())
+		omap_writel(val, OMAP2_GP_TIMER_BASE + reg);
+}
+
+static inline unsigned long omap_32k_timer_read(int reg)
+{
+	if (cpu_class_is_omap1())
+		return omap_readl(OMAP1_32K_TIMER_BASE + reg) & 0xffffff;
+
+	if (cpu_is_omap24xx())
+		return omap_readl(OMAP2_GP_TIMER_BASE + reg);
+}
+
+/*
+ * The 32KHz synchronized timer is an additional timer on 16xx.
+ * It is always running.
+ */
+static inline unsigned long omap_32k_sync_timer_read(void)
+{
+	return omap_readl(TIMER_32K_SYNCHRONIZED);
+}
+
+static inline void omap_32k_timer_start(unsigned long load_val)
+{
+	if (cpu_class_is_omap1()) {
+		omap_32k_timer_write(load_val, OMAP1_32K_TIMER_TVR);
+		omap_32k_timer_write(0x0f, OMAP1_32K_TIMER_CR);
+	}
+
+	if (cpu_is_omap24xx()) {
+		omap_32k_timer_write(0xffffffff - load_val, GP_TIMER_TCRR);
+		omap_32k_timer_write((1 << 1), GP_TIMER_TIER);
+		omap_32k_timer_write((1 << 1) | 1, GP_TIMER_TCLR);
+	}
+}
+
+static inline void omap_32k_timer_stop(void)
+{
+	if (cpu_class_is_omap1())
+		omap_32k_timer_write(0x0, OMAP1_32K_TIMER_CR);
+
+	if (cpu_is_omap24xx())
+		omap_32k_timer_write(0x0, GP_TIMER_TCLR);
+}
+
+/*
+ * Rounds down to nearest usec. Note that this will overflow for larger values.
+ */
+static inline unsigned long omap_32k_ticks_to_usecs(unsigned long ticks_32k)
+{
+	return (ticks_32k * 5*5*5*5*5*5) >> 9;
+}
+
+/*
+ * Rounds down to nearest nsec.
+ */
+static inline unsigned long long
+omap_32k_ticks_to_nsecs(unsigned long ticks_32k)
+{
+	return (unsigned long long) ticks_32k * 1000 * 5*5*5*5*5*5 >> 9;
+}
+
+static unsigned long omap_32k_last_tick = 0;
+
+/*
+ * Returns elapsed usecs since last 32k timer interrupt
+ */
+static unsigned long omap_32k_timer_gettimeoffset(void)
+{
+	unsigned long now = omap_32k_sync_timer_read();
+	return omap_32k_ticks_to_usecs(now - omap_32k_last_tick);
+}
+
+/*
+ * Returns current time from boot in nsecs. It's OK for this to wrap
+ * around for now, as it's just a relative time stamp.
+ */
+unsigned long long sched_clock(void)
+{
+	return omap_32k_ticks_to_nsecs(omap_32k_sync_timer_read());
+}
+
+/*
+ * Timer interrupt for 32KHz timer. When dynamic tick is enabled, this
+ * function is also called from other interrupts to remove latency
+ * issues with dynamic tick. In the dynamic tick case, we need to lock
+ * with irqsave.
+ */
+static irqreturn_t omap_32k_timer_interrupt(int irq, void *dev_id,
+					    struct pt_regs *regs)
+{
+	unsigned long flags;
+	unsigned long now;
+
+	write_seqlock_irqsave(&xtime_lock, flags);
+
+	if (cpu_is_omap24xx()) {
+		u32 status = omap_32k_timer_read(GP_TIMER_TISR);
+		omap_32k_timer_write(status, GP_TIMER_TISR);
+	}
+
+	now = omap_32k_sync_timer_read();
+
+	while (now - omap_32k_last_tick >= OMAP_32K_TICKS_PER_HZ) {
+		omap_32k_last_tick += OMAP_32K_TICKS_PER_HZ;
+		timer_tick(regs);
+	}
+
+	/* Restart timer so we don't drift off due to modulo or dynamic tick.
+	 * By default we program the next timer to be continuous to avoid
+	 * latencies during high system load. During dynamic tick operation the
+	 * continuous timer can be overridden from pm_idle to be longer.
+	 */
+	omap_32k_timer_start(omap_32k_last_tick + OMAP_32K_TICKS_PER_HZ - now);
+	write_sequnlock_irqrestore(&xtime_lock, flags);
+
+	return IRQ_HANDLED;
+}
+
+#ifdef CONFIG_NO_IDLE_HZ
+/*
+ * Programs the next timer interrupt needed. Called when dynamic tick is
+ * enabled, and to reprogram the ticks to skip from pm_idle. Note that
+ * we can keep the timer continuous, and don't need to set it to run in
+ * one-shot mode. This is because the timer will get reprogrammed again
+ * after next interrupt.
+ */
+void omap_32k_timer_reprogram(unsigned long next_tick)
+{
+	omap_32k_timer_start(JIFFIES_TO_HW_TICKS(next_tick, 32768) + 1);
+}
+
+static struct irqaction omap_32k_timer_irq;
+extern struct timer_update_handler timer_update;
+
+static int omap_32k_timer_enable_dyn_tick(void)
+{
+	/* No need to reprogram timer, just use the next interrupt */
+	return 0;
+}
+
+static int omap_32k_timer_disable_dyn_tick(void)
+{
+	omap_32k_timer_start(OMAP_32K_TIMER_TICK_PERIOD);
+	return 0;
+}
+
+static struct dyn_tick_timer omap_dyn_tick_timer = {
+	.enable		= omap_32k_timer_enable_dyn_tick,
+	.disable	= omap_32k_timer_disable_dyn_tick,
+	.reprogram	= omap_32k_timer_reprogram,
+	.handler	= omap_32k_timer_interrupt,
+};
+#endif	/* CONFIG_NO_IDLE_HZ */
+
+static struct irqaction omap_32k_timer_irq = {
+	.name		= "32KHz timer",
+	.flags		= SA_INTERRUPT | SA_TIMER,
+	.handler	= omap_32k_timer_interrupt,
+};
+
+static struct clk * gpt1_ick;
+static struct clk * gpt1_fck;
+
+static __init void omap_init_32k_timer(void)
+{
+#ifdef CONFIG_NO_IDLE_HZ
+	omap_timer.dyn_tick = &omap_dyn_tick_timer;
+#endif
+
+	if (cpu_class_is_omap1())
+		setup_irq(INT_OS_TIMER, &omap_32k_timer_irq);
+	if (cpu_is_omap24xx())
+		setup_irq(37, &omap_32k_timer_irq);
+	omap_timer.offset  = omap_32k_timer_gettimeoffset;
+	omap_32k_last_tick = omap_32k_sync_timer_read();
+
+	/* REVISIT: Check 24xx TIOCP_CFG settings after idle works */
+	if (cpu_is_omap24xx()) {
+		omap_32k_timer_write(0, GP_TIMER_TCLR);
+		omap_writel(0, CM_CLKSEL_WKUP);		/* 32KHz clock source */
+
+		gpt1_ick = clk_get(NULL, "gpt1_ick");
+		if (IS_ERR(gpt1_ick))
+			printk(KERN_ERR "Could not get gpt1_ick\n");
+		else
+			clk_enable(gpt1_ick);
+
+		gpt1_fck = clk_get(NULL, "gpt1_fck");
+		if (IS_ERR(gpt1_fck))
+			printk(KERN_ERR "Could not get gpt1_fck\n");
+		else
+			clk_enable(gpt1_fck);
+
+		mdelay(100);		/* Wait for clocks to stabilize */
+
+		omap_32k_timer_write(0x7, GP_TIMER_TISR);
+	}
+
+	omap_32k_timer_start(OMAP_32K_TIMER_TICK_PERIOD);
+}
+
+/*
+ * ---------------------------------------------------------------------------
+ * Timer initialization
+ * ---------------------------------------------------------------------------
+ */
+static void __init omap_timer_init(void)
+{
+	omap_init_32k_timer();
+}
+
+struct sys_timer omap_timer = {
+	.init		= omap_timer_init,
+	.offset		= NULL,		/* Initialized later */
+};