Merge tag 'soc-for-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

Pull ARM SoC platform changes from Olof Johansson:
 "This is the bulk of new SoC enablement and other platform changes for
  3.17:

   - Samsung S5PV210 has been converted to DT and multiplatform
   - Clock drivers and bindings for some of the lower-end i.MX 1/2
     platforms
   - Kirkwood, one of the popular Marvell platforms, is folded into the
     mvebu platform code, removing mach-kirkwood
   - Hwmod data for TI AM43xx and DRA7 platforms
   - More additions of Renesas shmobile platform support
   - Removal of plat-samsung contents that can be removed with S5PV210
     being multiplatform/DT-enabled and the other two old platforms
     being removed

  New platforms (most with only basic support right now):

   - Hisilicon X5HD2 settop box chipset is introduced
   - Mediatek MT6589 (mobile chipset) is introduced
   - Broadcom BCM7xxx settop box chipset is introduced

  + as usual a lot other pieces all over the platform code"

* tag 'soc-for-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (240 commits)
  ARM: hisi: remove smp from machine descriptor
  power: reset: move hisilicon reboot code
  ARM: dts: Add hix5hd2-dkb dts file.
  ARM: debug: Rename Hi3716 to HIX5HD2
  ARM: hisi: enable hix5hd2 SoC
  ARM: hisi: add ARCH_HISI
  MAINTAINERS: add entry for Broadcom ARM STB architecture
  ARM: brcmstb: select GISB arbiter and interrupt drivers
  ARM: brcmstb: add infrastructure for ARM-based Broadcom STB SoCs
  ARM: configs: enable SMP in bcm_defconfig
  ARM: add SMP support for Broadcom mobile SoCs
  Documentation: arm: misc updates to Marvell EBU SoC status
  Documentation: arm: add URLs to public datasheets for the Marvell Armada XP SoC
  ARM: mvebu: fix build without platforms selected
  ARM: mvebu: add cpuidle support for Armada 38x
  ARM: mvebu: add cpuidle support for Armada 370
  cpuidle: mvebu: add Armada 38x support
  cpuidle: mvebu: add Armada 370 support
  cpuidle: mvebu: rename the driver from armada-370-xp to mvebu-v7
  ARM: mvebu: export the SCU address
  ...

1 files changed, 22 insertions, 4 deletions

diff --git a/arch/arm/lib/delay.c b/arch/arm/lib/delay.c
index 5306de350133..312d43eb686a 100644
--- a/arch/arm/lib/delay.c
+++ b/arch/arm/lib/delay.c
@@ -19,6 +19,7 @@
  * Author: Will Deacon <will.deacon@arm.com>
  */
 
+#include <linux/clocksource.h>
 #include <linux/delay.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
@@ -36,6 +37,7 @@ struct arm_delay_ops arm_delay_ops = {
 
 static const struct delay_timer *delay_timer;
 static bool delay_calibrated;
+static u64 delay_res;
 
 int read_current_timer(unsigned long *timer_val)
 {
@@ -47,6 +49,11 @@ int read_current_timer(unsigned long *timer_val)
 }
 EXPORT_SYMBOL_GPL(read_current_timer);
 
+static inline u64 cyc_to_ns(u64 cyc, u32 mult, u32 shift)
+{
+	return (cyc * mult) >> shift;
+}
+
 static void __timer_delay(unsigned long cycles)
 {
 	cycles_t start = get_cycles();
@@ -69,18 +76,24 @@ static void __timer_udelay(unsigned long usecs)
 
 void __init register_current_timer_delay(const struct delay_timer *timer)
 {
-	if (!delay_calibrated) {
-		pr_info("Switching to timer-based delay loop\n");
+	u32 new_mult, new_shift;
+	u64 res;
+
+	clocks_calc_mult_shift(&new_mult, &new_shift, timer->freq,
+			       NSEC_PER_SEC, 3600);
+	res = cyc_to_ns(1ULL, new_mult, new_shift);
+
+	if (!delay_calibrated && (!delay_res || (res < delay_res))) {
+		pr_info("Switching to timer-based delay loop, resolution %lluns\n", res);
 		delay_timer			= timer;
 		lpj_fine			= timer->freq / HZ;
+		delay_res			= res;
 
 		/* cpufreq may scale loops_per_jiffy, so keep a private copy */
 		arm_delay_ops.ticks_per_jiffy	= lpj_fine;
 		arm_delay_ops.delay		= __timer_delay;
 		arm_delay_ops.const_udelay	= __timer_const_udelay;
 		arm_delay_ops.udelay		= __timer_udelay;
-
-		delay_calibrated		= true;
 	} else {
 		pr_info("Ignoring duplicate/late registration of read_current_timer delay\n");
 	}
@@ -91,3 +104,8 @@ unsigned long calibrate_delay_is_known(void)
 	delay_calibrated = true;
 	return lpj_fine;
 }
+
+void calibration_delay_done(void)
+{
+	delay_calibrated = true;
+}