arm: zynq: Move timer to generic location

Move zynq timer out of mach folder to generic location
and enable it.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>

3 files changed, 2 insertions, 437 deletions

diff --git a/arch/arm/mach-zynq/Kconfig b/arch/arm/mach-zynq/Kconfig
index adb6c0e..d70651e 100644
--- a/arch/arm/mach-zynq/Kconfig
+++ b/arch/arm/mach-zynq/Kconfig
@@ -9,5 +9,6 @@ config ARCH_ZYNQ
 	select MIGHT_HAVE_CACHE_L2X0
 	select USE_OF
 	select SPARSE_IRQ
+	select CADENCE_TTC_TIMER
 	help
 	  Support for Xilinx Zynq ARM Cortex A9 Platform
diff --git a/arch/arm/mach-zynq/Makefile b/arch/arm/mach-zynq/Makefile
index 397268c..320faed 100644
--- a/arch/arm/mach-zynq/Makefile
+++ b/arch/arm/mach-zynq/Makefile
@@ -3,4 +3,4 @@
 #
 
 # Common support
-obj-y				:= common.o timer.o
+obj-y				:= common.o
diff --git a/arch/arm/mach-zynq/timer.c b/arch/arm/mach-zynq/timer.c
deleted file mode 100644
index 685bc60..0000000
--- a/arch/arm/mach-zynq/timer.c
+++ /dev/null
@@ -1,436 +0,0 @@
-/*
- * This file contains driver for the Cadence Triple Timer Counter Rev 06
- *
- *  Copyright (C) 2011-2013 Xilinx
- *
- * based on arch/mips/kernel/time.c timer driver
- *
- * This software is licensed under the terms of the GNU General Public
- * License version 2, as published by the Free Software Foundation, and
- * may be copied, distributed, and modified under those terms.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- */
-
-#include <linux/clk.h>
-#include <linux/interrupt.h>
-#include <linux/clockchips.h>
-#include <linux/of_address.h>
-#include <linux/of_irq.h>
-#include <linux/slab.h>
-#include <linux/clk-provider.h>
-
-/*
- * This driver configures the 2 16-bit count-up timers as follows:
- *
- * T1: Timer 1, clocksource for generic timekeeping
- * T2: Timer 2, clockevent source for hrtimers
- * T3: Timer 3, <unused>
- *
- * The input frequency to the timer module for emulation is 2.5MHz which is
- * common to all the timer channels (T1, T2, and T3). With a pre-scaler of 32,
- * the timers are clocked at 78.125KHz (12.8 us resolution).
-
- * The input frequency to the timer module in silicon is configurable and
- * obtained from device tree. The pre-scaler of 32 is used.
- */
-
-/*
- * Timer Register Offset Definitions of Timer 1, Increment base address by 4
- * and use same offsets for Timer 2
- */
-#define TTC_CLK_CNTRL_OFFSET		0x00 /* Clock Control Reg, RW */
-#define TTC_CNT_CNTRL_OFFSET		0x0C /* Counter Control Reg, RW */
-#define TTC_COUNT_VAL_OFFSET		0x18 /* Counter Value Reg, RO */
-#define TTC_INTR_VAL_OFFSET		0x24 /* Interval Count Reg, RW */
-#define TTC_ISR_OFFSET		0x54 /* Interrupt Status Reg, RO */
-#define TTC_IER_OFFSET		0x60 /* Interrupt Enable Reg, RW */
-
-#define TTC_CNT_CNTRL_DISABLE_MASK	0x1
-
-/*
- * Setup the timers to use pre-scaling, using a fixed value for now that will
- * work across most input frequency, but it may need to be more dynamic
- */
-#define PRESCALE_EXPONENT	11	/* 2 ^ PRESCALE_EXPONENT = PRESCALE */
-#define PRESCALE		2048	/* The exponent must match this */
-#define CLK_CNTRL_PRESCALE	((PRESCALE_EXPONENT - 1) << 1)
-#define CLK_CNTRL_PRESCALE_EN	1
-#define CNT_CNTRL_RESET		(1 << 4)
-
-/**
- * struct ttc_timer - This definition defines local timer structure
- *
- * @base_addr:	Base address of timer
- * @clk:	Associated clock source
- * @clk_rate_change_nb	Notifier block for clock rate changes
- */
-struct ttc_timer {
-	void __iomem *base_addr;
-	struct clk *clk;
-	struct notifier_block clk_rate_change_nb;
-};
-
-#define to_ttc_timer(x) \
-		container_of(x, struct ttc_timer, clk_rate_change_nb)
-
-struct ttc_timer_clocksource {
-	struct ttc_timer	ttc;
-	struct clocksource	cs;
-};
-
-#define to_ttc_timer_clksrc(x) \
-		container_of(x, struct ttc_timer_clocksource, cs)
-
-struct ttc_timer_clockevent {
-	struct ttc_timer		ttc;
-	struct clock_event_device	ce;
-};
-
-#define to_ttc_timer_clkevent(x) \
-		container_of(x, struct ttc_timer_clockevent, ce)
-
-/**
- * ttc_set_interval - Set the timer interval value
- *
- * @timer:	Pointer to the timer instance
- * @cycles:	Timer interval ticks
- **/
-static void ttc_set_interval(struct ttc_timer *timer,
-					unsigned long cycles)
-{
-	u32 ctrl_reg;
-
-	/* Disable the counter, set the counter value  and re-enable counter */
-	ctrl_reg = __raw_readl(timer->base_addr + TTC_CNT_CNTRL_OFFSET);
-	ctrl_reg |= TTC_CNT_CNTRL_DISABLE_MASK;
-	__raw_writel(ctrl_reg, timer->base_addr + TTC_CNT_CNTRL_OFFSET);
-
-	__raw_writel(cycles, timer->base_addr + TTC_INTR_VAL_OFFSET);
-
-	/*
-	 * Reset the counter (0x10) so that it starts from 0, one-shot
-	 * mode makes this needed for timing to be right.
-	 */
-	ctrl_reg |= CNT_CNTRL_RESET;
-	ctrl_reg &= ~TTC_CNT_CNTRL_DISABLE_MASK;
-	__raw_writel(ctrl_reg, timer->base_addr + TTC_CNT_CNTRL_OFFSET);
-}
-
-/**
- * ttc_clock_event_interrupt - Clock event timer interrupt handler
- *
- * @irq:	IRQ number of the Timer
- * @dev_id:	void pointer to the ttc_timer instance
- *
- * returns: Always IRQ_HANDLED - success
- **/
-static irqreturn_t ttc_clock_event_interrupt(int irq, void *dev_id)
-{
-	struct ttc_timer_clockevent *ttce = dev_id;
-	struct ttc_timer *timer = &ttce->ttc;
-
-	/* Acknowledge the interrupt and call event handler */
-	__raw_readl(timer->base_addr + TTC_ISR_OFFSET);
-
-	ttce->ce.event_handler(&ttce->ce);
-
-	return IRQ_HANDLED;
-}
-
-/**
- * __ttc_clocksource_read - Reads the timer counter register
- *
- * returns: Current timer counter register value
- **/
-static cycle_t __ttc_clocksource_read(struct clocksource *cs)
-{
-	struct ttc_timer *timer = &to_ttc_timer_clksrc(cs)->ttc;
-
-	return (cycle_t)__raw_readl(timer->base_addr +
-				TTC_COUNT_VAL_OFFSET);
-}
-
-/**
- * ttc_set_next_event - Sets the time interval for next event
- *
- * @cycles:	Timer interval ticks
- * @evt:	Address of clock event instance
- *
- * returns: Always 0 - success
- **/
-static int ttc_set_next_event(unsigned long cycles,
-					struct clock_event_device *evt)
-{
-	struct ttc_timer_clockevent *ttce = to_ttc_timer_clkevent(evt);
-	struct ttc_timer *timer = &ttce->ttc;
-
-	ttc_set_interval(timer, cycles);
-	return 0;
-}
-
-/**
- * ttc_set_mode - Sets the mode of timer
- *
- * @mode:	Mode to be set
- * @evt:	Address of clock event instance
- **/
-static void ttc_set_mode(enum clock_event_mode mode,
-					struct clock_event_device *evt)
-{
-	struct ttc_timer_clockevent *ttce = to_ttc_timer_clkevent(evt);
-	struct ttc_timer *timer = &ttce->ttc;
-	u32 ctrl_reg;
-
-	switch (mode) {
-	case CLOCK_EVT_MODE_PERIODIC:
-		ttc_set_interval(timer,
-				DIV_ROUND_CLOSEST(clk_get_rate(ttce->ttc.clk),
-					PRESCALE * HZ));
-		break;
-	case CLOCK_EVT_MODE_ONESHOT:
-	case CLOCK_EVT_MODE_UNUSED:
-	case CLOCK_EVT_MODE_SHUTDOWN:
-		ctrl_reg = __raw_readl(timer->base_addr +
-					TTC_CNT_CNTRL_OFFSET);
-		ctrl_reg |= TTC_CNT_CNTRL_DISABLE_MASK;
-		__raw_writel(ctrl_reg,
-				timer->base_addr + TTC_CNT_CNTRL_OFFSET);
-		break;
-	case CLOCK_EVT_MODE_RESUME:
-		ctrl_reg = __raw_readl(timer->base_addr +
-					TTC_CNT_CNTRL_OFFSET);
-		ctrl_reg &= ~TTC_CNT_CNTRL_DISABLE_MASK;
-		__raw_writel(ctrl_reg,
-				timer->base_addr + TTC_CNT_CNTRL_OFFSET);
-		break;
-	}
-}
-
-static int ttc_rate_change_clocksource_cb(struct notifier_block *nb,
-		unsigned long event, void *data)
-{
-	struct clk_notifier_data *ndata = data;
-	struct ttc_timer *ttc = to_ttc_timer(nb);
-	struct ttc_timer_clocksource *ttccs = container_of(ttc,
-			struct ttc_timer_clocksource, ttc);
-
-	switch (event) {
-	case POST_RATE_CHANGE:
-		/*
-		 * Do whatever is necessary to maintain a proper time base
-		 *
-		 * I cannot find a way to adjust the currently used clocksource
-		 * to the new frequency. __clocksource_updatefreq_hz() sounds
-		 * good, but does not work. Not sure what's that missing.
-		 *
-		 * This approach works, but triggers two clocksource switches.
-		 * The first after unregister to clocksource jiffies. And
-		 * another one after the register to the newly registered timer.
-		 *
-		 * Alternatively we could 'waste' another HW timer to ping pong
-		 * between clock sources. That would also use one register and
-		 * one unregister call, but only trigger one clocksource switch
-		 * for the cost of another HW timer used by the OS.
-		 */
-		clocksource_unregister(&ttccs->cs);
-		clocksource_register_hz(&ttccs->cs,
-				ndata->new_rate / PRESCALE);
-		/* fall through */
-	case PRE_RATE_CHANGE:
-	case ABORT_RATE_CHANGE:
-	default:
-		return NOTIFY_DONE;
-	}
-}
-
-static void __init ttc_setup_clocksource(struct clk *clk, void __iomem *base)
-{
-	struct ttc_timer_clocksource *ttccs;
-	int err;
-
-	ttccs = kzalloc(sizeof(*ttccs), GFP_KERNEL);
-	if (WARN_ON(!ttccs))
-		return;
-
-	ttccs->ttc.clk = clk;
-
-	err = clk_prepare_enable(ttccs->ttc.clk);
-	if (WARN_ON(err)) {
-		kfree(ttccs);
-		return;
-	}
-
-	ttccs->ttc.clk_rate_change_nb.notifier_call =
-		ttc_rate_change_clocksource_cb;
-	ttccs->ttc.clk_rate_change_nb.next = NULL;
-	if (clk_notifier_register(ttccs->ttc.clk,
-				&ttccs->ttc.clk_rate_change_nb))
-		pr_warn("Unable to register clock notifier.\n");
-
-	ttccs->ttc.base_addr = base;
-	ttccs->cs.name = "ttc_clocksource";
-	ttccs->cs.rating = 200;
-	ttccs->cs.read = __ttc_clocksource_read;
-	ttccs->cs.mask = CLOCKSOURCE_MASK(16);
-	ttccs->cs.flags = CLOCK_SOURCE_IS_CONTINUOUS;
-
-	/*
-	 * Setup the clock source counter to be an incrementing counter
-	 * with no interrupt and it rolls over at 0xFFFF. Pre-scale
-	 * it by 32 also. Let it start running now.
-	 */
-	__raw_writel(0x0,  ttccs->ttc.base_addr + TTC_IER_OFFSET);
-	__raw_writel(CLK_CNTRL_PRESCALE | CLK_CNTRL_PRESCALE_EN,
-		     ttccs->ttc.base_addr + TTC_CLK_CNTRL_OFFSET);
-	__raw_writel(CNT_CNTRL_RESET,
-		     ttccs->ttc.base_addr + TTC_CNT_CNTRL_OFFSET);
-
-	err = clocksource_register_hz(&ttccs->cs,
-			clk_get_rate(ttccs->ttc.clk) / PRESCALE);
-	if (WARN_ON(err)) {
-		kfree(ttccs);
-		return;
-	}
-}
-
-static int ttc_rate_change_clockevent_cb(struct notifier_block *nb,
-		unsigned long event, void *data)
-{
-	struct clk_notifier_data *ndata = data;
-	struct ttc_timer *ttc = to_ttc_timer(nb);
-	struct ttc_timer_clockevent *ttcce = container_of(ttc,
-			struct ttc_timer_clockevent, ttc);
-
-	switch (event) {
-	case POST_RATE_CHANGE:
-	{
-		unsigned long flags;
-
-		/*
-		 * clockevents_update_freq should be called with IRQ disabled on
-		 * the CPU the timer provides events for. The timer we use is
-		 * common to both CPUs, not sure if we need to run on both
-		 * cores.
-		 */
-		local_irq_save(flags);
-		clockevents_update_freq(&ttcce->ce,
-				ndata->new_rate / PRESCALE);
-		local_irq_restore(flags);
-
-		/* fall through */
-	}
-	case PRE_RATE_CHANGE:
-	case ABORT_RATE_CHANGE:
-	default:
-		return NOTIFY_DONE;
-	}
-}
-
-static void __init ttc_setup_clockevent(struct clk *clk,
-						void __iomem *base, u32 irq)
-{
-	struct ttc_timer_clockevent *ttcce;
-	int err;
-
-	ttcce = kzalloc(sizeof(*ttcce), GFP_KERNEL);
-	if (WARN_ON(!ttcce))
-		return;
-
-	ttcce->ttc.clk = clk;
-
-	err = clk_prepare_enable(ttcce->ttc.clk);
-	if (WARN_ON(err)) {
-		kfree(ttcce);
-		return;
-	}
-
-	ttcce->ttc.clk_rate_change_nb.notifier_call =
-		ttc_rate_change_clockevent_cb;
-	ttcce->ttc.clk_rate_change_nb.next = NULL;
-	if (clk_notifier_register(ttcce->ttc.clk,
-				&ttcce->ttc.clk_rate_change_nb))
-		pr_warn("Unable to register clock notifier.\n");
-
-	ttcce->ttc.base_addr = base;
-	ttcce->ce.name = "ttc_clockevent";
-	ttcce->ce.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT;
-	ttcce->ce.set_next_event = ttc_set_next_event;
-	ttcce->ce.set_mode = ttc_set_mode;
-	ttcce->ce.rating = 200;
-	ttcce->ce.irq = irq;
-	ttcce->ce.cpumask = cpu_possible_mask;
-
-	/*
-	 * Setup the clock event timer to be an interval timer which
-	 * is prescaled by 32 using the interval interrupt. Leave it
-	 * disabled for now.
-	 */
-	__raw_writel(0x23, ttcce->ttc.base_addr + TTC_CNT_CNTRL_OFFSET);
-	__raw_writel(CLK_CNTRL_PRESCALE | CLK_CNTRL_PRESCALE_EN,
-		     ttcce->ttc.base_addr + TTC_CLK_CNTRL_OFFSET);
-	__raw_writel(0x1,  ttcce->ttc.base_addr + TTC_IER_OFFSET);
-
-	err = request_irq(irq, ttc_clock_event_interrupt,
-			  IRQF_DISABLED | IRQF_TIMER,
-			  ttcce->ce.name, ttcce);
-	if (WARN_ON(err)) {
-		kfree(ttcce);
-		return;
-	}
-
-	clockevents_config_and_register(&ttcce->ce,
-			clk_get_rate(ttcce->ttc.clk) / PRESCALE, 1, 0xfffe);
-}
-
-/**
- * ttc_timer_init - Initialize the timer
- *
- * Initializes the timer hardware and register the clock source and clock event
- * timers with Linux kernal timer framework
- */
-static void __init ttc_timer_init(struct device_node *timer)
-{
-	unsigned int irq;
-	void __iomem *timer_baseaddr;
-	struct clk *clk;
-	static int initialized;
-
-	if (initialized)
-		return;
-
-	initialized = 1;
-
-	/*
-	 * Get the 1st Triple Timer Counter (TTC) block from the device tree
-	 * and use it. Note that the event timer uses the interrupt and it's the
-	 * 2nd TTC hence the irq_of_parse_and_map(,1)
-	 */
-	timer_baseaddr = of_iomap(timer, 0);
-	if (!timer_baseaddr) {
-		pr_err("ERROR: invalid timer base address\n");
-		BUG();
-	}
-
-	irq = irq_of_parse_and_map(timer, 1);
-	if (irq <= 0) {
-		pr_err("ERROR: invalid interrupt number\n");
-		BUG();
-	}
-
-	clk = of_clk_get_by_name(timer, "cpu_1x");
-	if (IS_ERR(clk)) {
-		pr_err("ERROR: timer input clock not found\n");
-		BUG();
-	}
-
-	ttc_setup_clocksource(clk, timer_baseaddr);
-	ttc_setup_clockevent(clk, timer_baseaddr + 4, irq);
-
-	pr_info("%s #0 at %p, irq=%d\n", timer->name, timer_baseaddr, irq);
-}
-
-CLOCKSOURCE_OF_DECLARE(ttc, "cdns,ttc", ttc_timer_init);