]> git.karo-electronics.de Git - karo-tx-linux.git/blobdiff - drivers/clocksource/time-armada-370-xp.c
Merge branch 'timers/core' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
[karo-tx-linux.git] / drivers / clocksource / time-armada-370-xp.c
index 847cab6f6e31009f9a97560642ee4685497ead18..0198504ef6b02388c8847bc4897eca4e58328479 100644 (file)
  *
  * Timer 0 is used as free-running clocksource, while timer 1 is
  * used as clock_event_device.
+ *
+ * ---
+ * Clocksource driver for Armada 370 and Armada XP SoC.
+ * This driver implements one compatible string for each SoC, given
+ * each has its own characteristics:
+ *
+ *   * Armada 370 has no 25 MHz fixed timer.
+ *
+ *   * Armada XP cannot work properly without such 25 MHz fixed timer as
+ *     doing otherwise leads to using a clocksource whose frequency varies
+ *     when doing cpufreq frequency changes.
+ *
+ * See Documentation/devicetree/bindings/timer/marvell,armada-370-xp-timer.txt
  */
 
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/sched_clock.h>
 #include <linux/percpu.h>
-#include <linux/time-armada-370-xp.h>
 
 /*
  * Timer block registers.
  */
 #define TIMER_CTRL_OFF         0x0000
-#define  TIMER0_EN              0x0001
-#define  TIMER0_RELOAD_EN       0x0002
-#define  TIMER0_25MHZ            0x0800
+#define  TIMER0_EN              BIT(0)
+#define  TIMER0_RELOAD_EN       BIT(1)
+#define  TIMER0_25MHZ            BIT(11)
 #define  TIMER0_DIV(div)         ((div) << 19)
-#define  TIMER1_EN              0x0004
-#define  TIMER1_RELOAD_EN       0x0008
-#define  TIMER1_25MHZ            0x1000
+#define  TIMER1_EN              BIT(2)
+#define  TIMER1_RELOAD_EN       BIT(3)
+#define  TIMER1_25MHZ            BIT(12)
 #define  TIMER1_DIV(div)         ((div) << 22)
 #define TIMER_EVENTS_STATUS    0x0004
 #define  TIMER0_CLR_MASK         (~0x1)
@@ -72,6 +84,18 @@ static u32 ticks_per_jiffy;
 
 static struct clock_event_device __percpu *armada_370_xp_evt;
 
+static void timer_ctrl_clrset(u32 clr, u32 set)
+{
+       writel((readl(timer_base + TIMER_CTRL_OFF) & ~clr) | set,
+               timer_base + TIMER_CTRL_OFF);
+}
+
+static void local_timer_ctrl_clrset(u32 clr, u32 set)
+{
+       writel((readl(local_base + TIMER_CTRL_OFF) & ~clr) | set,
+               local_base + TIMER_CTRL_OFF);
+}
+
 static u32 notrace armada_370_xp_read_sched_clock(void)
 {
        return ~readl(timer_base + TIMER0_VAL_OFF);
@@ -84,7 +108,6 @@ static int
 armada_370_xp_clkevt_next_event(unsigned long delta,
                                struct clock_event_device *dev)
 {
-       u32 u;
        /*
         * Clear clockevent timer interrupt.
         */
@@ -98,11 +121,8 @@ armada_370_xp_clkevt_next_event(unsigned long delta,
        /*
         * Enable the timer.
         */
-       u = readl(local_base + TIMER_CTRL_OFF);
-       u = ((u & ~TIMER0_RELOAD_EN) | TIMER0_EN |
-            TIMER0_DIV(TIMER_DIVIDER_SHIFT));
-       writel(u, local_base + TIMER_CTRL_OFF);
-
+       local_timer_ctrl_clrset(TIMER0_RELOAD_EN,
+                               TIMER0_EN | TIMER0_DIV(TIMER_DIVIDER_SHIFT));
        return 0;
 }
 
@@ -110,8 +130,6 @@ static void
 armada_370_xp_clkevt_mode(enum clock_event_mode mode,
                          struct clock_event_device *dev)
 {
-       u32 u;
-
        if (mode == CLOCK_EVT_MODE_PERIODIC) {
 
                /*
@@ -123,18 +141,14 @@ armada_370_xp_clkevt_mode(enum clock_event_mode mode,
                /*
                 * Enable timer.
                 */
-
-               u = readl(local_base + TIMER_CTRL_OFF);
-
-               writel((u | TIMER0_EN | TIMER0_RELOAD_EN |
-                       TIMER0_DIV(TIMER_DIVIDER_SHIFT)),
-                       local_base + TIMER_CTRL_OFF);
+               local_timer_ctrl_clrset(0, TIMER0_RELOAD_EN |
+                                          TIMER0_EN |
+                                          TIMER0_DIV(TIMER_DIVIDER_SHIFT));
        } else {
                /*
                 * Disable timer.
                 */
-               u = readl(local_base + TIMER_CTRL_OFF);
-               writel(u & ~TIMER0_EN, local_base + TIMER_CTRL_OFF);
+               local_timer_ctrl_clrset(TIMER0_EN, 0);
 
                /*
                 * ACK pending timer interrupt.
@@ -163,14 +177,14 @@ static irqreturn_t armada_370_xp_timer_interrupt(int irq, void *dev_id)
  */
 static int armada_370_xp_timer_setup(struct clock_event_device *evt)
 {
-       u32 u;
+       u32 clr = 0, set = 0;
        int cpu = smp_processor_id();
 
-       u = readl(local_base + TIMER_CTRL_OFF);
        if (timer25Mhz)
-               writel(u | TIMER0_25MHZ, local_base + TIMER_CTRL_OFF);
+               set = TIMER0_25MHZ;
        else
-               writel(u & ~TIMER0_25MHZ, local_base + TIMER_CTRL_OFF);
+               clr = TIMER0_25MHZ;
+       local_timer_ctrl_clrset(clr, set);
 
        evt->name               = "armada_370_xp_per_cpu_tick",
        evt->features           = CLOCK_EVT_FEAT_ONESHOT |
@@ -217,36 +231,21 @@ static struct notifier_block armada_370_xp_timer_cpu_nb = {
        .notifier_call = armada_370_xp_timer_cpu_notify,
 };
 
-void __init armada_370_xp_timer_init(void)
+static void __init armada_370_xp_timer_common_init(struct device_node *np)
 {
-       u32 u;
-       struct device_node *np;
+       u32 clr = 0, set = 0;
        int res;
 
-       np = of_find_compatible_node(NULL, NULL, "marvell,armada-370-xp-timer");
        timer_base = of_iomap(np, 0);
        WARN_ON(!timer_base);
        local_base = of_iomap(np, 1);
 
-       if (of_find_property(np, "marvell,timer-25Mhz", NULL)) {
-               /* The fixed 25MHz timer is available so let's use it */
-               u = readl(timer_base + TIMER_CTRL_OFF);
-               writel(u | TIMER0_25MHZ,
-                      timer_base + TIMER_CTRL_OFF);
-               timer_clk = 25000000;
-       } else {
-               unsigned long rate = 0;
-               struct clk *clk = of_clk_get(np, 0);
-               WARN_ON(IS_ERR(clk));
-               rate =  clk_get_rate(clk);
-
-               u = readl(timer_base + TIMER_CTRL_OFF);
-               writel(u & ~(TIMER0_25MHZ),
-                      timer_base + TIMER_CTRL_OFF);
-
-               timer_clk = rate / TIMER_DIVIDER;
-               timer25Mhz = false;
-       }
+       if (timer25Mhz)
+               set = TIMER0_25MHZ;             
+       else
+               clr = TIMER0_25MHZ;
+       timer_ctrl_clrset(clr, set);
+       local_timer_ctrl_clrset(clr, set);
 
        /*
         * We use timer 0 as clocksource, and private(local) timer 0
@@ -268,10 +267,8 @@ void __init armada_370_xp_timer_init(void)
        writel(0xffffffff, timer_base + TIMER0_VAL_OFF);
        writel(0xffffffff, timer_base + TIMER0_RELOAD_OFF);
 
-       u = readl(timer_base + TIMER_CTRL_OFF);
-
-       writel((u | TIMER0_EN | TIMER0_RELOAD_EN |
-               TIMER0_DIV(TIMER_DIVIDER_SHIFT)), timer_base + TIMER_CTRL_OFF);
+       timer_ctrl_clrset(0, TIMER0_EN | TIMER0_RELOAD_EN |
+                            TIMER0_DIV(TIMER_DIVIDER_SHIFT));
 
        clocksource_mmio_init(timer_base + TIMER0_VAL_OFF,
                              "armada_370_xp_clocksource",
@@ -293,3 +290,29 @@ void __init armada_370_xp_timer_init(void)
        if (!res)
                armada_370_xp_timer_setup(this_cpu_ptr(armada_370_xp_evt));
 }
+
+static void __init armada_xp_timer_init(struct device_node *np)
+{
+       struct clk *clk = of_clk_get_by_name(np, "fixed");
+
+       /* The 25Mhz fixed clock is mandatory, and must always be available */
+       BUG_ON(IS_ERR(clk));
+       timer_clk = clk_get_rate(clk);
+
+       armada_370_xp_timer_common_init(np);
+}
+CLOCKSOURCE_OF_DECLARE(armada_xp, "marvell,armada-xp-timer",
+                      armada_xp_timer_init);
+
+static void __init armada_370_timer_init(struct device_node *np)
+{
+       struct clk *clk = of_clk_get(np, 0);
+
+       BUG_ON(IS_ERR(clk));
+       timer_clk = clk_get_rate(clk) / TIMER_DIVIDER;
+       timer25Mhz = false;
+
+       armada_370_xp_timer_common_init(np);
+}
+CLOCKSOURCE_OF_DECLARE(armada_370, "marvell,armada-370-timer",
+                      armada_370_timer_init);