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authorLinus Torvalds <torvalds@linux-foundation.org>2012-10-02 05:28:06 +0400
committerLinus Torvalds <torvalds@linux-foundation.org>2012-10-02 05:28:06 +0400
commit2a2bf85f05e42b12ea6bfe821e2d19221cf93555 (patch)
tree11abcdaef6e4f8307574056998d306d21558b6ed /arch/arm/mach-omap2/timer.c
parent11801e9de26992d37cb869cc74f389b6a7677e0e (diff)
parent99261fbad0a16f105b262d7525801697588ba526 (diff)
downloadlinux-2a2bf85f05e42b12ea6bfe821e2d19221cf93555.tar.xz
Merge tag 'dt' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM soc device tree updates from Olof Johansson: "Device tree conversion and enablement branch. Mostly a bunch of new bindings and setup for various platforms, but the Via/Winchip VT8500 platform is also converted over from being 100% legacy to now use device tree for probing. More of that will come for 3.8." Trivial conflicts due to removal of vt8500 files, and one documentation file that was added with slightly different contents both here and in the USb tree. * tag 'dt' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (212 commits) arm: vt8500: Fixup for missing gpio.h ARM: LPC32xx: LED fix in PHY3250 DTS file ARM: dt: mmp-dma: add binding file arm: vt8500: Update arch-vt8500 to devicetree support. arm: vt8500: gpio: Devicetree support for arch-vt8500 arm: vt8500: doc: Add device tree bindings for arch-vt8500 devices arm: vt8500: clk: Add Common Clock Framework support video: vt8500: Add devicetree support for vt8500-fb and wm8505-fb serial: vt8500: Add devicetree support for vt8500-serial rtc: vt8500: Add devicetree support for vt8500-rtc arm: vt8500: Add device tree files for VIA/Wondermedia SoC's ARM: tegra: Add Avionic Design Tamonten Evaluation Carrier support ARM: tegra: Add Avionic Design Medcom-Wide support ARM: tegra: Add Avionic Design Plutux support ARM: tegra: Add Avionic Design Tamonten support ARM: tegra: dts: Add pwm label ARM: ux500: Fix SSP register address format ARM: ux500: Apply tc3589x's GPIO/IRQ properties to HREF's DT ARM: ux500: Remove redundant #gpio-cell properties from Snowball DT ARM: ux500: Add all encompassing sound node to the HREF Device Tree ...
Diffstat (limited to 'arch/arm/mach-omap2/timer.c')
-rw-r--r--arch/arm/mach-omap2/timer.c103
1 files changed, 102 insertions, 1 deletions
diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c
index 5214d5bfba27..8847d6eb2313 100644
--- a/arch/arm/mach-omap2/timer.c
+++ b/arch/arm/mach-omap2/timer.c
@@ -36,11 +36,13 @@
#include <linux/clocksource.h>
#include <linux/clockchips.h>
#include <linux/slab.h>
+#include <linux/of.h>
#include <asm/mach/time.h>
#include <asm/smp_twd.h>
#include <asm/sched_clock.h>
+#include <asm/arch_timer.h>
#include <plat/omap_hwmod.h>
#include <plat/omap_device.h>
#include <plat/dmtimer.h>
@@ -71,6 +73,11 @@
#define OMAP3_SECURE_TIMER 1
#endif
+#define REALTIME_COUNTER_BASE 0x48243200
+#define INCREMENTER_NUMERATOR_OFFSET 0x10
+#define INCREMENTER_DENUMERATOR_RELOAD_OFFSET 0x14
+#define NUMERATOR_DENUMERATOR_MASK 0xfffff000
+
/* Clockevent code */
static struct omap_dm_timer clkev;
@@ -348,6 +355,84 @@ static void __init omap2_clocksource_init(int gptimer_id,
omap2_gptimer_clocksource_init(gptimer_id, fck_source);
}
+#ifdef CONFIG_SOC_HAS_REALTIME_COUNTER
+/*
+ * The realtime counter also called master counter, is a free-running
+ * counter, which is related to real time. It produces the count used
+ * by the CPU local timer peripherals in the MPU cluster. The timer counts
+ * at a rate of 6.144 MHz. Because the device operates on different clocks
+ * in different power modes, the master counter shifts operation between
+ * clocks, adjusting the increment per clock in hardware accordingly to
+ * maintain a constant count rate.
+ */
+static void __init realtime_counter_init(void)
+{
+ void __iomem *base;
+ static struct clk *sys_clk;
+ unsigned long rate;
+ unsigned int reg, num, den;
+
+ base = ioremap(REALTIME_COUNTER_BASE, SZ_32);
+ if (!base) {
+ pr_err("%s: ioremap failed\n", __func__);
+ return;
+ }
+ sys_clk = clk_get(NULL, "sys_clkin_ck");
+ if (!sys_clk) {
+ pr_err("%s: failed to get system clock handle\n", __func__);
+ iounmap(base);
+ return;
+ }
+
+ rate = clk_get_rate(sys_clk);
+ /* Numerator/denumerator values refer TRM Realtime Counter section */
+ switch (rate) {
+ case 1200000:
+ num = 64;
+ den = 125;
+ break;
+ case 1300000:
+ num = 768;
+ den = 1625;
+ break;
+ case 19200000:
+ num = 8;
+ den = 25;
+ break;
+ case 2600000:
+ num = 384;
+ den = 1625;
+ break;
+ case 2700000:
+ num = 256;
+ den = 1125;
+ break;
+ case 38400000:
+ default:
+ /* Program it for 38.4 MHz */
+ num = 4;
+ den = 25;
+ break;
+ }
+
+ /* Program numerator and denumerator registers */
+ reg = __raw_readl(base + INCREMENTER_NUMERATOR_OFFSET) &
+ NUMERATOR_DENUMERATOR_MASK;
+ reg |= num;
+ __raw_writel(reg, base + INCREMENTER_NUMERATOR_OFFSET);
+
+ reg = __raw_readl(base + INCREMENTER_NUMERATOR_OFFSET) &
+ NUMERATOR_DENUMERATOR_MASK;
+ reg |= den;
+ __raw_writel(reg, base + INCREMENTER_DENUMERATOR_RELOAD_OFFSET);
+
+ iounmap(base);
+}
+#else
+static inline void __init realtime_counter_init(void)
+{}
+#endif
+
#define OMAP_SYS_TIMER_INIT(name, clkev_nr, clkev_src, \
clksrc_nr, clksrc_src) \
static void __init omap##name##_timer_init(void) \
@@ -394,6 +479,11 @@ static void __init omap4_timer_init(void)
if (omap_rev() != OMAP4430_REV_ES1_0) {
int err;
+ if (of_have_populated_dt()) {
+ twd_local_timer_of_register();
+ return;
+ }
+
err = twd_local_timer_register(&twd_local_timer);
if (err)
pr_err("twd_local_timer_register failed %d\n", err);
@@ -404,7 +494,18 @@ OMAP_SYS_TIMER(4)
#endif
#ifdef CONFIG_SOC_OMAP5
-OMAP_SYS_TIMER_INIT(5, 1, OMAP4_CLKEV_SOURCE, 2, OMAP4_MPU_SOURCE)
+static void __init omap5_timer_init(void)
+{
+ int err;
+
+ omap2_gp_clockevent_init(1, OMAP4_CLKEV_SOURCE);
+ omap2_clocksource_init(2, OMAP4_MPU_SOURCE);
+ realtime_counter_init();
+
+ err = arch_timer_of_register();
+ if (err)
+ pr_err("%s: arch_timer_register failed %d\n", __func__, err);
+}
OMAP_SYS_TIMER(5)
#endif