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authorLinus Torvalds <torvalds@linux-foundation.org>2015-11-11 01:48:36 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2015-11-11 01:48:36 +0300
commita5e1d715a8d0696961d99d31d869aa522f1cad5a (patch)
treee89001ae08415360be9695c4f21548d0e07acaf9 /drivers/clocksource/timer-ti-32k.c
parent64fd8c8a0ff421b47a879fbff5b82563b7fb82f5 (diff)
parentd3dc3df6330e4b4d799bef4aac6f934b5e726b1c (diff)
downloadlinux-a5e1d715a8d0696961d99d31d869aa522f1cad5a.tar.xz
Merge tag 'armsoc-cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC cleanups from Olof Johansson: "Again we have a sizable (but not huge) cleanup branch with a net delta of about -3k lines. Main contents here is: - A bunch of development/cleanup of a few PXA boards - Removal of bockw platforms on shmobile, since the platform has now gone completely multiplatform. Whee! - move of the 32kHz timer on OMAP to a proper timesource - Misc cleanup of older OMAP material (incl removal of one board file) - Switch over to new common PWM lookup support for several platforms There's also a handful of other cleanups across the tree, but the above are the major pieces" * tag 'armsoc-cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (103 commits) ARM: OMAP3: hwmod data: Remove legacy mailbox data and addrs ARM: DRA7: hwmod data: Remove spinlock hwmod addrs ARM: OMAP4: hwmod data: Remove spinlock hwmod addrs ARM: DRA7/AM335x/AM437x: hwmod: Remove gpmc address space from hwmod data ARM: Remove __ref on hotplug cpu die path ARM: Remove open-coded version of IRQCHIP_DECLARE arm: omap2: board-generic: use omap4_local_timer_init for AM437x ARM: DRA7/AM335x/AM437x: hwmod: Remove elm address space from hwmod data ARM: OMAP: Remove duplicated operand in OR operation clocksource: ti-32k: make it depend on GENERIC_CLOCKSOURCE ARM: pxa: remove incorrect __init annotation on pxa27x_set_pwrmode ARM: pxa: raumfeld: make some variables static ARM: OMAP: Change all cpu_is_* occurences to soc_is_* for id.c ARM: OMAP2+: Rename cpu_is macros to soc_is arm: omap2: timer: limit hwmod usage to non-DT boots arm: omap2+: select 32k clocksource driver clocksource: add TI 32.768 Hz counter driver arm: omap2: timer: rename omap_sync32k_timer_init() arm: omap2: timer: always call clocksource_of_init() when DT arm: omap2: timer: move realtime_counter_init() around ...
Diffstat (limited to 'drivers/clocksource/timer-ti-32k.c')
-rw-r--r--drivers/clocksource/timer-ti-32k.c126
1 files changed, 126 insertions, 0 deletions
diff --git a/drivers/clocksource/timer-ti-32k.c b/drivers/clocksource/timer-ti-32k.c
new file mode 100644
index 000000000000..8518d9dfba5c
--- /dev/null
+++ b/drivers/clocksource/timer-ti-32k.c
@@ -0,0 +1,126 @@
+/**
+ * timer-ti-32k.c - OMAP2 32k Timer Support
+ *
+ * Copyright (C) 2009 Nokia Corporation
+ *
+ * Update to use new clocksource/clockevent layers
+ * Author: Kevin Hilman, MontaVista Software, Inc. <source@mvista.com>
+ * Copyright (C) 2007 MontaVista Software, Inc.
+ *
+ * Original driver:
+ * Copyright (C) 2005 Nokia Corporation
+ * Author: Paul Mundt <paul.mundt@nokia.com>
+ * Juha Yrjölä <juha.yrjola@nokia.com>
+ * OMAP Dual-mode timer framework support by Timo Teras
+ *
+ * Some parts based off of TI's 24xx code:
+ *
+ * Copyright (C) 2004-2009 Texas Instruments, Inc.
+ *
+ * Roughly modelled after the OMAP1 MPU timer code.
+ * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com>
+ *
+ * Copyright (C) 2015 Texas Instruments Incorporated - http://www.ti.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 of
+ * the License as published by the Free Software Foundation.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/init.h>
+#include <linux/time.h>
+#include <linux/sched_clock.h>
+#include <linux/clocksource.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+
+/*
+ * 32KHz clocksource ... always available, on pretty most chips except
+ * OMAP 730 and 1510. Other timers could be used as clocksources, with
+ * higher resolution in free-running counter modes (e.g. 12 MHz xtal),
+ * but systems won't necessarily want to spend resources that way.
+ */
+
+#define OMAP2_32KSYNCNT_REV_OFF 0x0
+#define OMAP2_32KSYNCNT_REV_SCHEME (0x3 << 30)
+#define OMAP2_32KSYNCNT_CR_OFF_LOW 0x10
+#define OMAP2_32KSYNCNT_CR_OFF_HIGH 0x30
+
+struct ti_32k {
+ void __iomem *base;
+ void __iomem *counter;
+ struct clocksource cs;
+};
+
+static inline struct ti_32k *to_ti_32k(struct clocksource *cs)
+{
+ return container_of(cs, struct ti_32k, cs);
+}
+
+static cycle_t ti_32k_read_cycles(struct clocksource *cs)
+{
+ struct ti_32k *ti = to_ti_32k(cs);
+
+ return (cycle_t)readl_relaxed(ti->counter);
+}
+
+static struct ti_32k ti_32k_timer = {
+ .cs = {
+ .name = "32k_counter",
+ .rating = 250,
+ .read = ti_32k_read_cycles,
+ .mask = CLOCKSOURCE_MASK(32),
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS |
+ CLOCK_SOURCE_SUSPEND_NONSTOP,
+ },
+};
+
+static u64 notrace omap_32k_read_sched_clock(void)
+{
+ return ti_32k_read_cycles(&ti_32k_timer.cs);
+}
+
+static void __init ti_32k_timer_init(struct device_node *np)
+{
+ int ret;
+
+ ti_32k_timer.base = of_iomap(np, 0);
+ if (!ti_32k_timer.base) {
+ pr_err("Can't ioremap 32k timer base\n");
+ return;
+ }
+
+ ti_32k_timer.counter = ti_32k_timer.base;
+
+ /*
+ * 32k sync Counter IP register offsets vary between the highlander
+ * version and the legacy ones.
+ *
+ * The 'SCHEME' bits(30-31) of the revision register is used to identify
+ * the version.
+ */
+ if (readl_relaxed(ti_32k_timer.base + OMAP2_32KSYNCNT_REV_OFF) &
+ OMAP2_32KSYNCNT_REV_SCHEME)
+ ti_32k_timer.counter += OMAP2_32KSYNCNT_CR_OFF_HIGH;
+ else
+ ti_32k_timer.counter += OMAP2_32KSYNCNT_CR_OFF_LOW;
+
+ ret = clocksource_register_hz(&ti_32k_timer.cs, 32768);
+ if (ret) {
+ pr_err("32k_counter: can't register clocksource\n");
+ return;
+ }
+
+ sched_clock_register(omap_32k_read_sched_clock, 32, 32768);
+ pr_info("OMAP clocksource: 32k_counter at 32768 Hz\n");
+}
+CLOCKSOURCE_OF_DECLARE(ti_32k_timer, "ti,omap-counter32k",
+ ti_32k_timer_init);