]> git.proxmox.com Git - mirror_ubuntu-zesty-kernel.git/commitdiff
ARM: u300: move timer driver to clocksource
authorLinus Walleij <linus.walleij@linaro.org>
Tue, 21 Jan 2014 14:04:14 +0000 (15:04 +0100)
committerDaniel Lezcano <daniel.lezcano@linaro.org>
Tue, 11 Mar 2014 22:04:43 +0000 (23:04 +0100)
Move the U300 timer driver down to the clocksource driver
subsystem and keep arch/arm clean.

Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
MAINTAINERS
arch/arm/mach-u300/Makefile
arch/arm/mach-u300/timer.c [deleted file]
drivers/clocksource/Makefile
drivers/clocksource/timer-u300.c [new file with mode: 0644]

index b2cf5cfb4d29de3dc27e351ba090134bfd624de6..edd6139c7c7c4596ac3620c5ca81102571c34c4d 100644 (file)
@@ -1319,6 +1319,7 @@ M:        Linus Walleij <linus.walleij@linaro.org>
 L:     linux-arm-kernel@lists.infradead.org (moderated for non-subscribers)
 S:     Supported
 F:     arch/arm/mach-u300/
+F:     drivers/clocksource/timer-u300.c
 F:     drivers/i2c/busses/i2c-stu300.c
 F:     drivers/rtc/rtc-coh901331.c
 F:     drivers/watchdog/coh901327_wdt.c
index 0f362b64fb878c02a03d4647ba7076353631b926..3ec74ac95bc1c1087c04776c0c1b2e6176273f4f 100644 (file)
@@ -2,7 +2,7 @@
 # Makefile for the linux kernel, U300 machine.
 #
 
-obj-y          := core.o timer.o
+obj-y          := core.o
 obj-m          :=
 obj-n          :=
 obj-           :=
diff --git a/arch/arm/mach-u300/timer.c b/arch/arm/mach-u300/timer.c
deleted file mode 100644 (file)
index fe08fd3..0000000
+++ /dev/null
@@ -1,451 +0,0 @@
-/*
- *
- * arch/arm/mach-u300/timer.c
- *
- *
- * Copyright (C) 2007-2009 ST-Ericsson AB
- * License terms: GNU General Public License (GPL) version 2
- * Timer COH 901 328, runs the OS timer interrupt.
- * Author: Linus Walleij <linus.walleij@stericsson.com>
- */
-#include <linux/interrupt.h>
-#include <linux/time.h>
-#include <linux/timex.h>
-#include <linux/clockchips.h>
-#include <linux/clocksource.h>
-#include <linux/types.h>
-#include <linux/io.h>
-#include <linux/clk.h>
-#include <linux/err.h>
-#include <linux/irq.h>
-#include <linux/delay.h>
-#include <linux/of_address.h>
-#include <linux/of_irq.h>
-#include <linux/sched_clock.h>
-
-/* Generic stuff */
-#include <asm/mach/map.h>
-#include <asm/mach/time.h>
-
-/*
- * APP side special timer registers
- * This timer contains four timers which can fire an interrupt each.
- * OS (operating system) timer @ 32768 Hz
- * DD (device driver) timer @ 1 kHz
- * GP1 (general purpose 1) timer @ 1MHz
- * GP2 (general purpose 2) timer @ 1MHz
- */
-
-/* Reset OS Timer 32bit (-/W) */
-#define U300_TIMER_APP_ROST                                    (0x0000)
-#define U300_TIMER_APP_ROST_TIMER_RESET                                (0x00000000)
-/* Enable OS Timer 32bit (-/W) */
-#define U300_TIMER_APP_EOST                                    (0x0004)
-#define U300_TIMER_APP_EOST_TIMER_ENABLE                       (0x00000000)
-/* Disable OS Timer 32bit (-/W) */
-#define U300_TIMER_APP_DOST                                    (0x0008)
-#define U300_TIMER_APP_DOST_TIMER_DISABLE                      (0x00000000)
-/* OS Timer Mode Register 32bit (-/W) */
-#define U300_TIMER_APP_SOSTM                                   (0x000c)
-#define U300_TIMER_APP_SOSTM_MODE_CONTINUOUS                   (0x00000000)
-#define U300_TIMER_APP_SOSTM_MODE_ONE_SHOT                     (0x00000001)
-/* OS Timer Status Register 32bit (R/-) */
-#define U300_TIMER_APP_OSTS                                    (0x0010)
-#define U300_TIMER_APP_OSTS_TIMER_STATE_MASK                   (0x0000000F)
-#define U300_TIMER_APP_OSTS_TIMER_STATE_IDLE                   (0x00000001)
-#define U300_TIMER_APP_OSTS_TIMER_STATE_ACTIVE                 (0x00000002)
-#define U300_TIMER_APP_OSTS_ENABLE_IND                         (0x00000010)
-#define U300_TIMER_APP_OSTS_MODE_MASK                          (0x00000020)
-#define U300_TIMER_APP_OSTS_MODE_CONTINUOUS                    (0x00000000)
-#define U300_TIMER_APP_OSTS_MODE_ONE_SHOT                      (0x00000020)
-#define U300_TIMER_APP_OSTS_IRQ_ENABLED_IND                    (0x00000040)
-#define U300_TIMER_APP_OSTS_IRQ_PENDING_IND                    (0x00000080)
-/* OS Timer Current Count Register 32bit (R/-) */
-#define U300_TIMER_APP_OSTCC                                   (0x0014)
-/* OS Timer Terminal Count Register 32bit (R/W) */
-#define U300_TIMER_APP_OSTTC                                   (0x0018)
-/* OS Timer Interrupt Enable Register 32bit (-/W) */
-#define U300_TIMER_APP_OSTIE                                   (0x001c)
-#define U300_TIMER_APP_OSTIE_IRQ_DISABLE                       (0x00000000)
-#define U300_TIMER_APP_OSTIE_IRQ_ENABLE                                (0x00000001)
-/* OS Timer Interrupt Acknowledge Register 32bit (-/W) */
-#define U300_TIMER_APP_OSTIA                                   (0x0020)
-#define U300_TIMER_APP_OSTIA_IRQ_ACK                           (0x00000080)
-
-/* Reset DD Timer 32bit (-/W) */
-#define U300_TIMER_APP_RDDT                                    (0x0040)
-#define U300_TIMER_APP_RDDT_TIMER_RESET                                (0x00000000)
-/* Enable DD Timer 32bit (-/W) */
-#define U300_TIMER_APP_EDDT                                    (0x0044)
-#define U300_TIMER_APP_EDDT_TIMER_ENABLE                       (0x00000000)
-/* Disable DD Timer 32bit (-/W) */
-#define U300_TIMER_APP_DDDT                                    (0x0048)
-#define U300_TIMER_APP_DDDT_TIMER_DISABLE                      (0x00000000)
-/* DD Timer Mode Register 32bit (-/W) */
-#define U300_TIMER_APP_SDDTM                                   (0x004c)
-#define U300_TIMER_APP_SDDTM_MODE_CONTINUOUS                   (0x00000000)
-#define U300_TIMER_APP_SDDTM_MODE_ONE_SHOT                     (0x00000001)
-/* DD Timer Status Register 32bit (R/-) */
-#define U300_TIMER_APP_DDTS                                    (0x0050)
-#define U300_TIMER_APP_DDTS_TIMER_STATE_MASK                   (0x0000000F)
-#define U300_TIMER_APP_DDTS_TIMER_STATE_IDLE                   (0x00000001)
-#define U300_TIMER_APP_DDTS_TIMER_STATE_ACTIVE                 (0x00000002)
-#define U300_TIMER_APP_DDTS_ENABLE_IND                         (0x00000010)
-#define U300_TIMER_APP_DDTS_MODE_MASK                          (0x00000020)
-#define U300_TIMER_APP_DDTS_MODE_CONTINUOUS                    (0x00000000)
-#define U300_TIMER_APP_DDTS_MODE_ONE_SHOT                      (0x00000020)
-#define U300_TIMER_APP_DDTS_IRQ_ENABLED_IND                    (0x00000040)
-#define U300_TIMER_APP_DDTS_IRQ_PENDING_IND                    (0x00000080)
-/* DD Timer Current Count Register 32bit (R/-) */
-#define U300_TIMER_APP_DDTCC                                   (0x0054)
-/* DD Timer Terminal Count Register 32bit (R/W) */
-#define U300_TIMER_APP_DDTTC                                   (0x0058)
-/* DD Timer Interrupt Enable Register 32bit (-/W) */
-#define U300_TIMER_APP_DDTIE                                   (0x005c)
-#define U300_TIMER_APP_DDTIE_IRQ_DISABLE                       (0x00000000)
-#define U300_TIMER_APP_DDTIE_IRQ_ENABLE                                (0x00000001)
-/* DD Timer Interrupt Acknowledge Register 32bit (-/W) */
-#define U300_TIMER_APP_DDTIA                                   (0x0060)
-#define U300_TIMER_APP_DDTIA_IRQ_ACK                           (0x00000080)
-
-/* Reset GP1 Timer 32bit (-/W) */
-#define U300_TIMER_APP_RGPT1                                   (0x0080)
-#define U300_TIMER_APP_RGPT1_TIMER_RESET                       (0x00000000)
-/* Enable GP1 Timer 32bit (-/W) */
-#define U300_TIMER_APP_EGPT1                                   (0x0084)
-#define U300_TIMER_APP_EGPT1_TIMER_ENABLE                      (0x00000000)
-/* Disable GP1 Timer 32bit (-/W) */
-#define U300_TIMER_APP_DGPT1                                   (0x0088)
-#define U300_TIMER_APP_DGPT1_TIMER_DISABLE                     (0x00000000)
-/* GP1 Timer Mode Register 32bit (-/W) */
-#define U300_TIMER_APP_SGPT1M                                  (0x008c)
-#define U300_TIMER_APP_SGPT1M_MODE_CONTINUOUS                  (0x00000000)
-#define U300_TIMER_APP_SGPT1M_MODE_ONE_SHOT                    (0x00000001)
-/* GP1 Timer Status Register 32bit (R/-) */
-#define U300_TIMER_APP_GPT1S                                   (0x0090)
-#define U300_TIMER_APP_GPT1S_TIMER_STATE_MASK                  (0x0000000F)
-#define U300_TIMER_APP_GPT1S_TIMER_STATE_IDLE                  (0x00000001)
-#define U300_TIMER_APP_GPT1S_TIMER_STATE_ACTIVE                        (0x00000002)
-#define U300_TIMER_APP_GPT1S_ENABLE_IND                                (0x00000010)
-#define U300_TIMER_APP_GPT1S_MODE_MASK                         (0x00000020)
-#define U300_TIMER_APP_GPT1S_MODE_CONTINUOUS                   (0x00000000)
-#define U300_TIMER_APP_GPT1S_MODE_ONE_SHOT                     (0x00000020)
-#define U300_TIMER_APP_GPT1S_IRQ_ENABLED_IND                   (0x00000040)
-#define U300_TIMER_APP_GPT1S_IRQ_PENDING_IND                   (0x00000080)
-/* GP1 Timer Current Count Register 32bit (R/-) */
-#define U300_TIMER_APP_GPT1CC                                  (0x0094)
-/* GP1 Timer Terminal Count Register 32bit (R/W) */
-#define U300_TIMER_APP_GPT1TC                                  (0x0098)
-/* GP1 Timer Interrupt Enable Register 32bit (-/W) */
-#define U300_TIMER_APP_GPT1IE                                  (0x009c)
-#define U300_TIMER_APP_GPT1IE_IRQ_DISABLE                      (0x00000000)
-#define U300_TIMER_APP_GPT1IE_IRQ_ENABLE                       (0x00000001)
-/* GP1 Timer Interrupt Acknowledge Register 32bit (-/W) */
-#define U300_TIMER_APP_GPT1IA                                  (0x00a0)
-#define U300_TIMER_APP_GPT1IA_IRQ_ACK                          (0x00000080)
-
-/* Reset GP2 Timer 32bit (-/W) */
-#define U300_TIMER_APP_RGPT2                                   (0x00c0)
-#define U300_TIMER_APP_RGPT2_TIMER_RESET                       (0x00000000)
-/* Enable GP2 Timer 32bit (-/W) */
-#define U300_TIMER_APP_EGPT2                                   (0x00c4)
-#define U300_TIMER_APP_EGPT2_TIMER_ENABLE                      (0x00000000)
-/* Disable GP2 Timer 32bit (-/W) */
-#define U300_TIMER_APP_DGPT2                                   (0x00c8)
-#define U300_TIMER_APP_DGPT2_TIMER_DISABLE                     (0x00000000)
-/* GP2 Timer Mode Register 32bit (-/W) */
-#define U300_TIMER_APP_SGPT2M                                  (0x00cc)
-#define U300_TIMER_APP_SGPT2M_MODE_CONTINUOUS                  (0x00000000)
-#define U300_TIMER_APP_SGPT2M_MODE_ONE_SHOT                    (0x00000001)
-/* GP2 Timer Status Register 32bit (R/-) */
-#define U300_TIMER_APP_GPT2S                                   (0x00d0)
-#define U300_TIMER_APP_GPT2S_TIMER_STATE_MASK                  (0x0000000F)
-#define U300_TIMER_APP_GPT2S_TIMER_STATE_IDLE                  (0x00000001)
-#define U300_TIMER_APP_GPT2S_TIMER_STATE_ACTIVE                        (0x00000002)
-#define U300_TIMER_APP_GPT2S_ENABLE_IND                                (0x00000010)
-#define U300_TIMER_APP_GPT2S_MODE_MASK                         (0x00000020)
-#define U300_TIMER_APP_GPT2S_MODE_CONTINUOUS                   (0x00000000)
-#define U300_TIMER_APP_GPT2S_MODE_ONE_SHOT                     (0x00000020)
-#define U300_TIMER_APP_GPT2S_IRQ_ENABLED_IND                   (0x00000040)
-#define U300_TIMER_APP_GPT2S_IRQ_PENDING_IND                   (0x00000080)
-/* GP2 Timer Current Count Register 32bit (R/-) */
-#define U300_TIMER_APP_GPT2CC                                  (0x00d4)
-/* GP2 Timer Terminal Count Register 32bit (R/W) */
-#define U300_TIMER_APP_GPT2TC                                  (0x00d8)
-/* GP2 Timer Interrupt Enable Register 32bit (-/W) */
-#define U300_TIMER_APP_GPT2IE                                  (0x00dc)
-#define U300_TIMER_APP_GPT2IE_IRQ_DISABLE                      (0x00000000)
-#define U300_TIMER_APP_GPT2IE_IRQ_ENABLE                       (0x00000001)
-/* GP2 Timer Interrupt Acknowledge Register 32bit (-/W) */
-#define U300_TIMER_APP_GPT2IA                                  (0x00e0)
-#define U300_TIMER_APP_GPT2IA_IRQ_ACK                          (0x00000080)
-
-/* Clock request control register - all four timers */
-#define U300_TIMER_APP_CRC                                     (0x100)
-#define U300_TIMER_APP_CRC_CLOCK_REQUEST_ENABLE                        (0x00000001)
-
-static void __iomem *u300_timer_base;
-
-struct u300_clockevent_data {
-       struct clock_event_device cevd;
-       unsigned ticks_per_jiffy;
-};
-
-/*
- * The u300_set_mode() function is always called first, if we
- * have oneshot timer active, the oneshot scheduling function
- * u300_set_next_event() is called immediately after.
- */
-static void u300_set_mode(enum clock_event_mode mode,
-                         struct clock_event_device *evt)
-{
-       struct u300_clockevent_data *cevdata =
-               container_of(evt, struct u300_clockevent_data, cevd);
-
-       switch (mode) {
-       case CLOCK_EVT_MODE_PERIODIC:
-               /* Disable interrupts on GPT1 */
-               writel(U300_TIMER_APP_GPT1IE_IRQ_DISABLE,
-                      u300_timer_base + U300_TIMER_APP_GPT1IE);
-               /* Disable GP1 while we're reprogramming it. */
-               writel(U300_TIMER_APP_DGPT1_TIMER_DISABLE,
-                      u300_timer_base + U300_TIMER_APP_DGPT1);
-               /*
-                * Set the periodic mode to a certain number of ticks per
-                * jiffy.
-                */
-               writel(cevdata->ticks_per_jiffy,
-                      u300_timer_base + U300_TIMER_APP_GPT1TC);
-               /*
-                * Set continuous mode, so the timer keeps triggering
-                * interrupts.
-                */
-               writel(U300_TIMER_APP_SGPT1M_MODE_CONTINUOUS,
-                      u300_timer_base + U300_TIMER_APP_SGPT1M);
-               /* Enable timer interrupts */
-               writel(U300_TIMER_APP_GPT1IE_IRQ_ENABLE,
-                      u300_timer_base + U300_TIMER_APP_GPT1IE);
-               /* Then enable the OS timer again */
-               writel(U300_TIMER_APP_EGPT1_TIMER_ENABLE,
-                      u300_timer_base + U300_TIMER_APP_EGPT1);
-               break;
-       case CLOCK_EVT_MODE_ONESHOT:
-               /* Just break; here? */
-               /*
-                * The actual event will be programmed by the next event hook,
-                * so we just set a dummy value somewhere at the end of the
-                * universe here.
-                */
-               /* Disable interrupts on GPT1 */
-               writel(U300_TIMER_APP_GPT1IE_IRQ_DISABLE,
-                      u300_timer_base + U300_TIMER_APP_GPT1IE);
-               /* Disable GP1 while we're reprogramming it. */
-               writel(U300_TIMER_APP_DGPT1_TIMER_DISABLE,
-                      u300_timer_base + U300_TIMER_APP_DGPT1);
-               /*
-                * Expire far in the future, u300_set_next_event() will be
-                * called soon...
-                */
-               writel(0xFFFFFFFF, u300_timer_base + U300_TIMER_APP_GPT1TC);
-               /* We run one shot per tick here! */
-               writel(U300_TIMER_APP_SGPT1M_MODE_ONE_SHOT,
-                      u300_timer_base + U300_TIMER_APP_SGPT1M);
-               /* Enable interrupts for this timer */
-               writel(U300_TIMER_APP_GPT1IE_IRQ_ENABLE,
-                      u300_timer_base + U300_TIMER_APP_GPT1IE);
-               /* Enable timer */
-               writel(U300_TIMER_APP_EGPT1_TIMER_ENABLE,
-                      u300_timer_base + U300_TIMER_APP_EGPT1);
-               break;
-       case CLOCK_EVT_MODE_UNUSED:
-       case CLOCK_EVT_MODE_SHUTDOWN:
-               /* Disable interrupts on GP1 */
-               writel(U300_TIMER_APP_GPT1IE_IRQ_DISABLE,
-                      u300_timer_base + U300_TIMER_APP_GPT1IE);
-               /* Disable GP1 */
-               writel(U300_TIMER_APP_DGPT1_TIMER_DISABLE,
-                      u300_timer_base + U300_TIMER_APP_DGPT1);
-               break;
-       case CLOCK_EVT_MODE_RESUME:
-               /* Ignore this call */
-               break;
-       }
-}
-
-/*
- * The app timer in one shot mode obviously has to be reprogrammed
- * in EXACTLY this sequence to work properly. Do NOT try to e.g. replace
- * the interrupt disable + timer disable commands with a reset command,
- * it will fail miserably. Apparently (and I found this the hard way)
- * the timer is very sensitive to the instruction order, though you don't
- * get that impression from the data sheet.
- */
-static int u300_set_next_event(unsigned long cycles,
-                              struct clock_event_device *evt)
-
-{
-       /* Disable interrupts on GPT1 */
-       writel(U300_TIMER_APP_GPT1IE_IRQ_DISABLE,
-              u300_timer_base + U300_TIMER_APP_GPT1IE);
-       /* Disable GP1 while we're reprogramming it. */
-       writel(U300_TIMER_APP_DGPT1_TIMER_DISABLE,
-              u300_timer_base + U300_TIMER_APP_DGPT1);
-       /* Reset the General Purpose timer 1. */
-       writel(U300_TIMER_APP_RGPT1_TIMER_RESET,
-              u300_timer_base + U300_TIMER_APP_RGPT1);
-       /* IRQ in n * cycles */
-       writel(cycles, u300_timer_base + U300_TIMER_APP_GPT1TC);
-       /*
-        * We run one shot per tick here! (This is necessary to reconfigure,
-        * the timer will tilt if you don't!)
-        */
-       writel(U300_TIMER_APP_SGPT1M_MODE_ONE_SHOT,
-              u300_timer_base + U300_TIMER_APP_SGPT1M);
-       /* Enable timer interrupts */
-       writel(U300_TIMER_APP_GPT1IE_IRQ_ENABLE,
-              u300_timer_base + U300_TIMER_APP_GPT1IE);
-       /* Then enable the OS timer again */
-       writel(U300_TIMER_APP_EGPT1_TIMER_ENABLE,
-              u300_timer_base + U300_TIMER_APP_EGPT1);
-       return 0;
-}
-
-static struct u300_clockevent_data u300_clockevent_data = {
-       /* Use general purpose timer 1 as clock event */
-       .cevd = {
-               .name           = "GPT1",
-               /* Reasonably fast and accurate clock event */
-               .rating         = 300,
-               .features       = CLOCK_EVT_FEAT_PERIODIC |
-                       CLOCK_EVT_FEAT_ONESHOT,
-               .set_next_event = u300_set_next_event,
-               .set_mode       = u300_set_mode,
-       },
-};
-
-/* Clock event timer interrupt handler */
-static irqreturn_t u300_timer_interrupt(int irq, void *dev_id)
-{
-       struct clock_event_device *evt = &u300_clockevent_data.cevd;
-       /* ACK/Clear timer IRQ for the APP GPT1 Timer */
-
-       writel(U300_TIMER_APP_GPT1IA_IRQ_ACK,
-               u300_timer_base + U300_TIMER_APP_GPT1IA);
-       evt->event_handler(evt);
-       return IRQ_HANDLED;
-}
-
-static struct irqaction u300_timer_irq = {
-       .name           = "U300 Timer Tick",
-       .flags          = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
-       .handler        = u300_timer_interrupt,
-};
-
-/*
- * Override the global weak sched_clock symbol with this
- * local implementation which uses the clocksource to get some
- * better resolution when scheduling the kernel. We accept that
- * this wraps around for now, since it is just a relative time
- * stamp. (Inspired by OMAP implementation.)
- */
-
-static u64 notrace u300_read_sched_clock(void)
-{
-       return readl(u300_timer_base + U300_TIMER_APP_GPT2CC);
-}
-
-static unsigned long u300_read_current_timer(void)
-{
-       return readl(u300_timer_base + U300_TIMER_APP_GPT2CC);
-}
-
-static struct delay_timer u300_delay_timer;
-
-/*
- * This sets up the system timers, clock source and clock event.
- */
-static void __init u300_timer_init_of(struct device_node *np)
-{
-       unsigned int irq;
-       struct clk *clk;
-       unsigned long rate;
-
-       u300_timer_base = of_iomap(np, 0);
-       if (!u300_timer_base)
-               panic("could not ioremap system timer\n");
-
-       /* Get the IRQ for the GP1 timer */
-       irq = irq_of_parse_and_map(np, 2);
-       if (!irq)
-               panic("no IRQ for system timer\n");
-
-       pr_info("U300 GP1 timer @ base: %p, IRQ: %u\n", u300_timer_base, irq);
-
-       /* Clock the interrupt controller */
-       clk = of_clk_get(np, 0);
-       BUG_ON(IS_ERR(clk));
-       clk_prepare_enable(clk);
-       rate = clk_get_rate(clk);
-
-       u300_clockevent_data.ticks_per_jiffy = DIV_ROUND_CLOSEST(rate, HZ);
-
-       sched_clock_register(u300_read_sched_clock, 32, rate);
-
-       u300_delay_timer.read_current_timer = &u300_read_current_timer;
-       u300_delay_timer.freq = rate;
-       register_current_timer_delay(&u300_delay_timer);
-
-       /*
-        * Disable the "OS" and "DD" timers - these are designed for Symbian!
-        * Example usage in cnh1601578 cpu subsystem pd_timer_app.c
-        */
-       writel(U300_TIMER_APP_CRC_CLOCK_REQUEST_ENABLE,
-               u300_timer_base + U300_TIMER_APP_CRC);
-       writel(U300_TIMER_APP_ROST_TIMER_RESET,
-               u300_timer_base + U300_TIMER_APP_ROST);
-       writel(U300_TIMER_APP_DOST_TIMER_DISABLE,
-               u300_timer_base + U300_TIMER_APP_DOST);
-       writel(U300_TIMER_APP_RDDT_TIMER_RESET,
-               u300_timer_base + U300_TIMER_APP_RDDT);
-       writel(U300_TIMER_APP_DDDT_TIMER_DISABLE,
-               u300_timer_base + U300_TIMER_APP_DDDT);
-
-       /* Reset the General Purpose timer 1. */
-       writel(U300_TIMER_APP_RGPT1_TIMER_RESET,
-               u300_timer_base + U300_TIMER_APP_RGPT1);
-
-       /* Set up the IRQ handler */
-       setup_irq(irq, &u300_timer_irq);
-
-       /* Reset the General Purpose timer 2 */
-       writel(U300_TIMER_APP_RGPT2_TIMER_RESET,
-               u300_timer_base + U300_TIMER_APP_RGPT2);
-       /* Set this timer to run around forever */
-       writel(0xFFFFFFFFU, u300_timer_base + U300_TIMER_APP_GPT2TC);
-       /* Set continuous mode so it wraps around */
-       writel(U300_TIMER_APP_SGPT2M_MODE_CONTINUOUS,
-              u300_timer_base + U300_TIMER_APP_SGPT2M);
-       /* Disable timer interrupts */
-       writel(U300_TIMER_APP_GPT2IE_IRQ_DISABLE,
-               u300_timer_base + U300_TIMER_APP_GPT2IE);
-       /* Then enable the GP2 timer to use as a free running us counter */
-       writel(U300_TIMER_APP_EGPT2_TIMER_ENABLE,
-               u300_timer_base + U300_TIMER_APP_EGPT2);
-
-       /* Use general purpose timer 2 as clock source */
-       if (clocksource_mmio_init(u300_timer_base + U300_TIMER_APP_GPT2CC,
-                       "GPT2", rate, 300, 32, clocksource_mmio_readl_up))
-               pr_err("timer: failed to initialize U300 clock source\n");
-
-       /* Configure and register the clockevent */
-       clockevents_config_and_register(&u300_clockevent_data.cevd, rate,
-                                       1, 0xffffffff);
-
-       /*
-        * TODO: init and register the rest of the timers too, they can be
-        * used by hrtimers!
-        */
-}
-
-CLOCKSOURCE_OF_DECLARE(u300_timer, "stericsson,u300-apptimer",
-                      u300_timer_init_of);
index c7ca50a9c232bdcc246fbce2508f71ff6dbcab97..01e5435315cabc793eea40b0bda31e1e64504c41 100644 (file)
@@ -21,6 +21,7 @@ obj-$(CONFIG_ARCH_MARCO)      += timer-marco.o
 obj-$(CONFIG_ARCH_MOXART)      += moxart_timer.o
 obj-$(CONFIG_ARCH_MXS)         += mxs_timer.o
 obj-$(CONFIG_ARCH_PRIMA2)      += timer-prima2.o
+obj-$(CONFIG_ARCH_U300)                += timer-u300.o
 obj-$(CONFIG_SUN4I_TIMER)      += sun4i_timer.o
 obj-$(CONFIG_SUN5I_HSTIMER)    += timer-sun5i.o
 obj-$(CONFIG_ARCH_TEGRA)       += tegra20_timer.o
diff --git a/drivers/clocksource/timer-u300.c b/drivers/clocksource/timer-u300.c
new file mode 100644 (file)
index 0000000..e63d469
--- /dev/null
@@ -0,0 +1,447 @@
+/*
+ * Copyright (C) 2007-2009 ST-Ericsson AB
+ * License terms: GNU General Public License (GPL) version 2
+ * Timer COH 901 328, runs the OS timer interrupt.
+ * Author: Linus Walleij <linus.walleij@stericsson.com>
+ */
+#include <linux/interrupt.h>
+#include <linux/time.h>
+#include <linux/timex.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/types.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/irq.h>
+#include <linux/delay.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/sched_clock.h>
+
+/* Generic stuff */
+#include <asm/mach/map.h>
+#include <asm/mach/time.h>
+
+/*
+ * APP side special timer registers
+ * This timer contains four timers which can fire an interrupt each.
+ * OS (operating system) timer @ 32768 Hz
+ * DD (device driver) timer @ 1 kHz
+ * GP1 (general purpose 1) timer @ 1MHz
+ * GP2 (general purpose 2) timer @ 1MHz
+ */
+
+/* Reset OS Timer 32bit (-/W) */
+#define U300_TIMER_APP_ROST                                    (0x0000)
+#define U300_TIMER_APP_ROST_TIMER_RESET                                (0x00000000)
+/* Enable OS Timer 32bit (-/W) */
+#define U300_TIMER_APP_EOST                                    (0x0004)
+#define U300_TIMER_APP_EOST_TIMER_ENABLE                       (0x00000000)
+/* Disable OS Timer 32bit (-/W) */
+#define U300_TIMER_APP_DOST                                    (0x0008)
+#define U300_TIMER_APP_DOST_TIMER_DISABLE                      (0x00000000)
+/* OS Timer Mode Register 32bit (-/W) */
+#define U300_TIMER_APP_SOSTM                                   (0x000c)
+#define U300_TIMER_APP_SOSTM_MODE_CONTINUOUS                   (0x00000000)
+#define U300_TIMER_APP_SOSTM_MODE_ONE_SHOT                     (0x00000001)
+/* OS Timer Status Register 32bit (R/-) */
+#define U300_TIMER_APP_OSTS                                    (0x0010)
+#define U300_TIMER_APP_OSTS_TIMER_STATE_MASK                   (0x0000000F)
+#define U300_TIMER_APP_OSTS_TIMER_STATE_IDLE                   (0x00000001)
+#define U300_TIMER_APP_OSTS_TIMER_STATE_ACTIVE                 (0x00000002)
+#define U300_TIMER_APP_OSTS_ENABLE_IND                         (0x00000010)
+#define U300_TIMER_APP_OSTS_MODE_MASK                          (0x00000020)
+#define U300_TIMER_APP_OSTS_MODE_CONTINUOUS                    (0x00000000)
+#define U300_TIMER_APP_OSTS_MODE_ONE_SHOT                      (0x00000020)
+#define U300_TIMER_APP_OSTS_IRQ_ENABLED_IND                    (0x00000040)
+#define U300_TIMER_APP_OSTS_IRQ_PENDING_IND                    (0x00000080)
+/* OS Timer Current Count Register 32bit (R/-) */
+#define U300_TIMER_APP_OSTCC                                   (0x0014)
+/* OS Timer Terminal Count Register 32bit (R/W) */
+#define U300_TIMER_APP_OSTTC                                   (0x0018)
+/* OS Timer Interrupt Enable Register 32bit (-/W) */
+#define U300_TIMER_APP_OSTIE                                   (0x001c)
+#define U300_TIMER_APP_OSTIE_IRQ_DISABLE                       (0x00000000)
+#define U300_TIMER_APP_OSTIE_IRQ_ENABLE                                (0x00000001)
+/* OS Timer Interrupt Acknowledge Register 32bit (-/W) */
+#define U300_TIMER_APP_OSTIA                                   (0x0020)
+#define U300_TIMER_APP_OSTIA_IRQ_ACK                           (0x00000080)
+
+/* Reset DD Timer 32bit (-/W) */
+#define U300_TIMER_APP_RDDT                                    (0x0040)
+#define U300_TIMER_APP_RDDT_TIMER_RESET                                (0x00000000)
+/* Enable DD Timer 32bit (-/W) */
+#define U300_TIMER_APP_EDDT                                    (0x0044)
+#define U300_TIMER_APP_EDDT_TIMER_ENABLE                       (0x00000000)
+/* Disable DD Timer 32bit (-/W) */
+#define U300_TIMER_APP_DDDT                                    (0x0048)
+#define U300_TIMER_APP_DDDT_TIMER_DISABLE                      (0x00000000)
+/* DD Timer Mode Register 32bit (-/W) */
+#define U300_TIMER_APP_SDDTM                                   (0x004c)
+#define U300_TIMER_APP_SDDTM_MODE_CONTINUOUS                   (0x00000000)
+#define U300_TIMER_APP_SDDTM_MODE_ONE_SHOT                     (0x00000001)
+/* DD Timer Status Register 32bit (R/-) */
+#define U300_TIMER_APP_DDTS                                    (0x0050)
+#define U300_TIMER_APP_DDTS_TIMER_STATE_MASK                   (0x0000000F)
+#define U300_TIMER_APP_DDTS_TIMER_STATE_IDLE                   (0x00000001)
+#define U300_TIMER_APP_DDTS_TIMER_STATE_ACTIVE                 (0x00000002)
+#define U300_TIMER_APP_DDTS_ENABLE_IND                         (0x00000010)
+#define U300_TIMER_APP_DDTS_MODE_MASK                          (0x00000020)
+#define U300_TIMER_APP_DDTS_MODE_CONTINUOUS                    (0x00000000)
+#define U300_TIMER_APP_DDTS_MODE_ONE_SHOT                      (0x00000020)
+#define U300_TIMER_APP_DDTS_IRQ_ENABLED_IND                    (0x00000040)
+#define U300_TIMER_APP_DDTS_IRQ_PENDING_IND                    (0x00000080)
+/* DD Timer Current Count Register 32bit (R/-) */
+#define U300_TIMER_APP_DDTCC                                   (0x0054)
+/* DD Timer Terminal Count Register 32bit (R/W) */
+#define U300_TIMER_APP_DDTTC                                   (0x0058)
+/* DD Timer Interrupt Enable Register 32bit (-/W) */
+#define U300_TIMER_APP_DDTIE                                   (0x005c)
+#define U300_TIMER_APP_DDTIE_IRQ_DISABLE                       (0x00000000)
+#define U300_TIMER_APP_DDTIE_IRQ_ENABLE                                (0x00000001)
+/* DD Timer Interrupt Acknowledge Register 32bit (-/W) */
+#define U300_TIMER_APP_DDTIA                                   (0x0060)
+#define U300_TIMER_APP_DDTIA_IRQ_ACK                           (0x00000080)
+
+/* Reset GP1 Timer 32bit (-/W) */
+#define U300_TIMER_APP_RGPT1                                   (0x0080)
+#define U300_TIMER_APP_RGPT1_TIMER_RESET                       (0x00000000)
+/* Enable GP1 Timer 32bit (-/W) */
+#define U300_TIMER_APP_EGPT1                                   (0x0084)
+#define U300_TIMER_APP_EGPT1_TIMER_ENABLE                      (0x00000000)
+/* Disable GP1 Timer 32bit (-/W) */
+#define U300_TIMER_APP_DGPT1                                   (0x0088)
+#define U300_TIMER_APP_DGPT1_TIMER_DISABLE                     (0x00000000)
+/* GP1 Timer Mode Register 32bit (-/W) */
+#define U300_TIMER_APP_SGPT1M                                  (0x008c)
+#define U300_TIMER_APP_SGPT1M_MODE_CONTINUOUS                  (0x00000000)
+#define U300_TIMER_APP_SGPT1M_MODE_ONE_SHOT                    (0x00000001)
+/* GP1 Timer Status Register 32bit (R/-) */
+#define U300_TIMER_APP_GPT1S                                   (0x0090)
+#define U300_TIMER_APP_GPT1S_TIMER_STATE_MASK                  (0x0000000F)
+#define U300_TIMER_APP_GPT1S_TIMER_STATE_IDLE                  (0x00000001)
+#define U300_TIMER_APP_GPT1S_TIMER_STATE_ACTIVE                        (0x00000002)
+#define U300_TIMER_APP_GPT1S_ENABLE_IND                                (0x00000010)
+#define U300_TIMER_APP_GPT1S_MODE_MASK                         (0x00000020)
+#define U300_TIMER_APP_GPT1S_MODE_CONTINUOUS                   (0x00000000)
+#define U300_TIMER_APP_GPT1S_MODE_ONE_SHOT                     (0x00000020)
+#define U300_TIMER_APP_GPT1S_IRQ_ENABLED_IND                   (0x00000040)
+#define U300_TIMER_APP_GPT1S_IRQ_PENDING_IND                   (0x00000080)
+/* GP1 Timer Current Count Register 32bit (R/-) */
+#define U300_TIMER_APP_GPT1CC                                  (0x0094)
+/* GP1 Timer Terminal Count Register 32bit (R/W) */
+#define U300_TIMER_APP_GPT1TC                                  (0x0098)
+/* GP1 Timer Interrupt Enable Register 32bit (-/W) */
+#define U300_TIMER_APP_GPT1IE                                  (0x009c)
+#define U300_TIMER_APP_GPT1IE_IRQ_DISABLE                      (0x00000000)
+#define U300_TIMER_APP_GPT1IE_IRQ_ENABLE                       (0x00000001)
+/* GP1 Timer Interrupt Acknowledge Register 32bit (-/W) */
+#define U300_TIMER_APP_GPT1IA                                  (0x00a0)
+#define U300_TIMER_APP_GPT1IA_IRQ_ACK                          (0x00000080)
+
+/* Reset GP2 Timer 32bit (-/W) */
+#define U300_TIMER_APP_RGPT2                                   (0x00c0)
+#define U300_TIMER_APP_RGPT2_TIMER_RESET                       (0x00000000)
+/* Enable GP2 Timer 32bit (-/W) */
+#define U300_TIMER_APP_EGPT2                                   (0x00c4)
+#define U300_TIMER_APP_EGPT2_TIMER_ENABLE                      (0x00000000)
+/* Disable GP2 Timer 32bit (-/W) */
+#define U300_TIMER_APP_DGPT2                                   (0x00c8)
+#define U300_TIMER_APP_DGPT2_TIMER_DISABLE                     (0x00000000)
+/* GP2 Timer Mode Register 32bit (-/W) */
+#define U300_TIMER_APP_SGPT2M                                  (0x00cc)
+#define U300_TIMER_APP_SGPT2M_MODE_CONTINUOUS                  (0x00000000)
+#define U300_TIMER_APP_SGPT2M_MODE_ONE_SHOT                    (0x00000001)
+/* GP2 Timer Status Register 32bit (R/-) */
+#define U300_TIMER_APP_GPT2S                                   (0x00d0)
+#define U300_TIMER_APP_GPT2S_TIMER_STATE_MASK                  (0x0000000F)
+#define U300_TIMER_APP_GPT2S_TIMER_STATE_IDLE                  (0x00000001)
+#define U300_TIMER_APP_GPT2S_TIMER_STATE_ACTIVE                        (0x00000002)
+#define U300_TIMER_APP_GPT2S_ENABLE_IND                                (0x00000010)
+#define U300_TIMER_APP_GPT2S_MODE_MASK                         (0x00000020)
+#define U300_TIMER_APP_GPT2S_MODE_CONTINUOUS                   (0x00000000)
+#define U300_TIMER_APP_GPT2S_MODE_ONE_SHOT                     (0x00000020)
+#define U300_TIMER_APP_GPT2S_IRQ_ENABLED_IND                   (0x00000040)
+#define U300_TIMER_APP_GPT2S_IRQ_PENDING_IND                   (0x00000080)
+/* GP2 Timer Current Count Register 32bit (R/-) */
+#define U300_TIMER_APP_GPT2CC                                  (0x00d4)
+/* GP2 Timer Terminal Count Register 32bit (R/W) */
+#define U300_TIMER_APP_GPT2TC                                  (0x00d8)
+/* GP2 Timer Interrupt Enable Register 32bit (-/W) */
+#define U300_TIMER_APP_GPT2IE                                  (0x00dc)
+#define U300_TIMER_APP_GPT2IE_IRQ_DISABLE                      (0x00000000)
+#define U300_TIMER_APP_GPT2IE_IRQ_ENABLE                       (0x00000001)
+/* GP2 Timer Interrupt Acknowledge Register 32bit (-/W) */
+#define U300_TIMER_APP_GPT2IA                                  (0x00e0)
+#define U300_TIMER_APP_GPT2IA_IRQ_ACK                          (0x00000080)
+
+/* Clock request control register - all four timers */
+#define U300_TIMER_APP_CRC                                     (0x100)
+#define U300_TIMER_APP_CRC_CLOCK_REQUEST_ENABLE                        (0x00000001)
+
+static void __iomem *u300_timer_base;
+
+struct u300_clockevent_data {
+       struct clock_event_device cevd;
+       unsigned ticks_per_jiffy;
+};
+
+/*
+ * The u300_set_mode() function is always called first, if we
+ * have oneshot timer active, the oneshot scheduling function
+ * u300_set_next_event() is called immediately after.
+ */
+static void u300_set_mode(enum clock_event_mode mode,
+                         struct clock_event_device *evt)
+{
+       struct u300_clockevent_data *cevdata =
+               container_of(evt, struct u300_clockevent_data, cevd);
+
+       switch (mode) {
+       case CLOCK_EVT_MODE_PERIODIC:
+               /* Disable interrupts on GPT1 */
+               writel(U300_TIMER_APP_GPT1IE_IRQ_DISABLE,
+                      u300_timer_base + U300_TIMER_APP_GPT1IE);
+               /* Disable GP1 while we're reprogramming it. */
+               writel(U300_TIMER_APP_DGPT1_TIMER_DISABLE,
+                      u300_timer_base + U300_TIMER_APP_DGPT1);
+               /*
+                * Set the periodic mode to a certain number of ticks per
+                * jiffy.
+                */
+               writel(cevdata->ticks_per_jiffy,
+                      u300_timer_base + U300_TIMER_APP_GPT1TC);
+               /*
+                * Set continuous mode, so the timer keeps triggering
+                * interrupts.
+                */
+               writel(U300_TIMER_APP_SGPT1M_MODE_CONTINUOUS,
+                      u300_timer_base + U300_TIMER_APP_SGPT1M);
+               /* Enable timer interrupts */
+               writel(U300_TIMER_APP_GPT1IE_IRQ_ENABLE,
+                      u300_timer_base + U300_TIMER_APP_GPT1IE);
+               /* Then enable the OS timer again */
+               writel(U300_TIMER_APP_EGPT1_TIMER_ENABLE,
+                      u300_timer_base + U300_TIMER_APP_EGPT1);
+               break;
+       case CLOCK_EVT_MODE_ONESHOT:
+               /* Just break; here? */
+               /*
+                * The actual event will be programmed by the next event hook,
+                * so we just set a dummy value somewhere at the end of the
+                * universe here.
+                */
+               /* Disable interrupts on GPT1 */
+               writel(U300_TIMER_APP_GPT1IE_IRQ_DISABLE,
+                      u300_timer_base + U300_TIMER_APP_GPT1IE);
+               /* Disable GP1 while we're reprogramming it. */
+               writel(U300_TIMER_APP_DGPT1_TIMER_DISABLE,
+                      u300_timer_base + U300_TIMER_APP_DGPT1);
+               /*
+                * Expire far in the future, u300_set_next_event() will be
+                * called soon...
+                */
+               writel(0xFFFFFFFF, u300_timer_base + U300_TIMER_APP_GPT1TC);
+               /* We run one shot per tick here! */
+               writel(U300_TIMER_APP_SGPT1M_MODE_ONE_SHOT,
+                      u300_timer_base + U300_TIMER_APP_SGPT1M);
+               /* Enable interrupts for this timer */
+               writel(U300_TIMER_APP_GPT1IE_IRQ_ENABLE,
+                      u300_timer_base + U300_TIMER_APP_GPT1IE);
+               /* Enable timer */
+               writel(U300_TIMER_APP_EGPT1_TIMER_ENABLE,
+                      u300_timer_base + U300_TIMER_APP_EGPT1);
+               break;
+       case CLOCK_EVT_MODE_UNUSED:
+       case CLOCK_EVT_MODE_SHUTDOWN:
+               /* Disable interrupts on GP1 */
+               writel(U300_TIMER_APP_GPT1IE_IRQ_DISABLE,
+                      u300_timer_base + U300_TIMER_APP_GPT1IE);
+               /* Disable GP1 */
+               writel(U300_TIMER_APP_DGPT1_TIMER_DISABLE,
+                      u300_timer_base + U300_TIMER_APP_DGPT1);
+               break;
+       case CLOCK_EVT_MODE_RESUME:
+               /* Ignore this call */
+               break;
+       }
+}
+
+/*
+ * The app timer in one shot mode obviously has to be reprogrammed
+ * in EXACTLY this sequence to work properly. Do NOT try to e.g. replace
+ * the interrupt disable + timer disable commands with a reset command,
+ * it will fail miserably. Apparently (and I found this the hard way)
+ * the timer is very sensitive to the instruction order, though you don't
+ * get that impression from the data sheet.
+ */
+static int u300_set_next_event(unsigned long cycles,
+                              struct clock_event_device *evt)
+
+{
+       /* Disable interrupts on GPT1 */
+       writel(U300_TIMER_APP_GPT1IE_IRQ_DISABLE,
+              u300_timer_base + U300_TIMER_APP_GPT1IE);
+       /* Disable GP1 while we're reprogramming it. */
+       writel(U300_TIMER_APP_DGPT1_TIMER_DISABLE,
+              u300_timer_base + U300_TIMER_APP_DGPT1);
+       /* Reset the General Purpose timer 1. */
+       writel(U300_TIMER_APP_RGPT1_TIMER_RESET,
+              u300_timer_base + U300_TIMER_APP_RGPT1);
+       /* IRQ in n * cycles */
+       writel(cycles, u300_timer_base + U300_TIMER_APP_GPT1TC);
+       /*
+        * We run one shot per tick here! (This is necessary to reconfigure,
+        * the timer will tilt if you don't!)
+        */
+       writel(U300_TIMER_APP_SGPT1M_MODE_ONE_SHOT,
+              u300_timer_base + U300_TIMER_APP_SGPT1M);
+       /* Enable timer interrupts */
+       writel(U300_TIMER_APP_GPT1IE_IRQ_ENABLE,
+              u300_timer_base + U300_TIMER_APP_GPT1IE);
+       /* Then enable the OS timer again */
+       writel(U300_TIMER_APP_EGPT1_TIMER_ENABLE,
+              u300_timer_base + U300_TIMER_APP_EGPT1);
+       return 0;
+}
+
+static struct u300_clockevent_data u300_clockevent_data = {
+       /* Use general purpose timer 1 as clock event */
+       .cevd = {
+               .name           = "GPT1",
+               /* Reasonably fast and accurate clock event */
+               .rating         = 300,
+               .features       = CLOCK_EVT_FEAT_PERIODIC |
+                       CLOCK_EVT_FEAT_ONESHOT,
+               .set_next_event = u300_set_next_event,
+               .set_mode       = u300_set_mode,
+       },
+};
+
+/* Clock event timer interrupt handler */
+static irqreturn_t u300_timer_interrupt(int irq, void *dev_id)
+{
+       struct clock_event_device *evt = &u300_clockevent_data.cevd;
+       /* ACK/Clear timer IRQ for the APP GPT1 Timer */
+
+       writel(U300_TIMER_APP_GPT1IA_IRQ_ACK,
+               u300_timer_base + U300_TIMER_APP_GPT1IA);
+       evt->event_handler(evt);
+       return IRQ_HANDLED;
+}
+
+static struct irqaction u300_timer_irq = {
+       .name           = "U300 Timer Tick",
+       .flags          = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
+       .handler        = u300_timer_interrupt,
+};
+
+/*
+ * Override the global weak sched_clock symbol with this
+ * local implementation which uses the clocksource to get some
+ * better resolution when scheduling the kernel. We accept that
+ * this wraps around for now, since it is just a relative time
+ * stamp. (Inspired by OMAP implementation.)
+ */
+
+static u64 notrace u300_read_sched_clock(void)
+{
+       return readl(u300_timer_base + U300_TIMER_APP_GPT2CC);
+}
+
+static unsigned long u300_read_current_timer(void)
+{
+       return readl(u300_timer_base + U300_TIMER_APP_GPT2CC);
+}
+
+static struct delay_timer u300_delay_timer;
+
+/*
+ * This sets up the system timers, clock source and clock event.
+ */
+static void __init u300_timer_init_of(struct device_node *np)
+{
+       unsigned int irq;
+       struct clk *clk;
+       unsigned long rate;
+
+       u300_timer_base = of_iomap(np, 0);
+       if (!u300_timer_base)
+               panic("could not ioremap system timer\n");
+
+       /* Get the IRQ for the GP1 timer */
+       irq = irq_of_parse_and_map(np, 2);
+       if (!irq)
+               panic("no IRQ for system timer\n");
+
+       pr_info("U300 GP1 timer @ base: %p, IRQ: %u\n", u300_timer_base, irq);
+
+       /* Clock the interrupt controller */
+       clk = of_clk_get(np, 0);
+       BUG_ON(IS_ERR(clk));
+       clk_prepare_enable(clk);
+       rate = clk_get_rate(clk);
+
+       u300_clockevent_data.ticks_per_jiffy = DIV_ROUND_CLOSEST(rate, HZ);
+
+       sched_clock_register(u300_read_sched_clock, 32, rate);
+
+       u300_delay_timer.read_current_timer = &u300_read_current_timer;
+       u300_delay_timer.freq = rate;
+       register_current_timer_delay(&u300_delay_timer);
+
+       /*
+        * Disable the "OS" and "DD" timers - these are designed for Symbian!
+        * Example usage in cnh1601578 cpu subsystem pd_timer_app.c
+        */
+       writel(U300_TIMER_APP_CRC_CLOCK_REQUEST_ENABLE,
+               u300_timer_base + U300_TIMER_APP_CRC);
+       writel(U300_TIMER_APP_ROST_TIMER_RESET,
+               u300_timer_base + U300_TIMER_APP_ROST);
+       writel(U300_TIMER_APP_DOST_TIMER_DISABLE,
+               u300_timer_base + U300_TIMER_APP_DOST);
+       writel(U300_TIMER_APP_RDDT_TIMER_RESET,
+               u300_timer_base + U300_TIMER_APP_RDDT);
+       writel(U300_TIMER_APP_DDDT_TIMER_DISABLE,
+               u300_timer_base + U300_TIMER_APP_DDDT);
+
+       /* Reset the General Purpose timer 1. */
+       writel(U300_TIMER_APP_RGPT1_TIMER_RESET,
+               u300_timer_base + U300_TIMER_APP_RGPT1);
+
+       /* Set up the IRQ handler */
+       setup_irq(irq, &u300_timer_irq);
+
+       /* Reset the General Purpose timer 2 */
+       writel(U300_TIMER_APP_RGPT2_TIMER_RESET,
+               u300_timer_base + U300_TIMER_APP_RGPT2);
+       /* Set this timer to run around forever */
+       writel(0xFFFFFFFFU, u300_timer_base + U300_TIMER_APP_GPT2TC);
+       /* Set continuous mode so it wraps around */
+       writel(U300_TIMER_APP_SGPT2M_MODE_CONTINUOUS,
+              u300_timer_base + U300_TIMER_APP_SGPT2M);
+       /* Disable timer interrupts */
+       writel(U300_TIMER_APP_GPT2IE_IRQ_DISABLE,
+               u300_timer_base + U300_TIMER_APP_GPT2IE);
+       /* Then enable the GP2 timer to use as a free running us counter */
+       writel(U300_TIMER_APP_EGPT2_TIMER_ENABLE,
+               u300_timer_base + U300_TIMER_APP_EGPT2);
+
+       /* Use general purpose timer 2 as clock source */
+       if (clocksource_mmio_init(u300_timer_base + U300_TIMER_APP_GPT2CC,
+                       "GPT2", rate, 300, 32, clocksource_mmio_readl_up))
+               pr_err("timer: failed to initialize U300 clock source\n");
+
+       /* Configure and register the clockevent */
+       clockevents_config_and_register(&u300_clockevent_data.cevd, rate,
+                                       1, 0xffffffff);
+
+       /*
+        * TODO: init and register the rest of the timers too, they can be
+        * used by hrtimers!
+        */
+}
+
+CLOCKSOURCE_OF_DECLARE(u300_timer, "stericsson,u300-apptimer",
+                      u300_timer_init_of);