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authorSascha Hauer <s.hauer@pengutronix.de>2014-06-04 21:04:28 +0200
committerSascha Hauer <s.hauer@pengutronix.de>2014-06-04 21:04:28 +0200
commitcd667b7468e67963a8af46fa1914963a089894d7 (patch)
treee2bd85420a0a10ee2184884be0dd7cea86536cb9 /drivers
parentad9f56888f00afca589e3a9e14ff856cebf540a7 (diff)
parentc480d32813b25b2a1269b67d77552ecae405e740 (diff)
downloadbarebox-cd667b7468e67963a8af46fa1914963a089894d7.tar.gz
barebox-cd667b7468e67963a8af46fa1914963a089894d7.tar.xz
Merge branch 'for-next/uemd'
Diffstat (limited to 'drivers')
-rw-r--r--drivers/clocksource/Kconfig4
-rw-r--r--drivers/clocksource/Makefile1
-rw-r--r--drivers/clocksource/uemd.c130
3 files changed, 135 insertions, 0 deletions
diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index 43974f03c2..c1480ceaaf 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -48,3 +48,7 @@ config CLOCKSOURCE_NOMADIK
config CLOCKSOURCE_ORION
bool
depends on ARCH_MVEBU
+
+config CLOCKSOURCE_UEMD
+ bool
+ depends on ARCH_UEMD
diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index 834a15d1e9..97c0288aaa 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -6,3 +6,4 @@ obj-$(CONFIG_CLOCKSOURCE_DUMMY) += dummy.o
obj-$(CONFIG_CLOCKSOURCE_MVEBU) += mvebu.o
obj-$(CONFIG_CLOCKSOURCE_NOMADIK) += nomadik.o
obj-$(CONFIG_CLOCKSOURCE_ORION) += orion.o
+obj-$(CONFIG_CLOCKSOURCE_UEMD) += uemd.o
diff --git a/drivers/clocksource/uemd.c b/drivers/clocksource/uemd.c
new file mode 100644
index 0000000000..2ea455edfa
--- /dev/null
+++ b/drivers/clocksource/uemd.c
@@ -0,0 +1,130 @@
+/*
+ * Copyright (C) 2014 Antony Pavlov <antonynpavlov@gmail.com>
+ *
+ * Based on
+ * https://github.com/RC-MODULE/linux-3.10.x/tree/k1879-3.10.28/arch/arm/mach-uemd/clocksource.c
+ * (C) 2011 RC Module, Sergey Mironov <ierton@gmail.com>
+ *
+ * This file is part of barebox.
+ * See file CREDITS for list of people who contributed to this project.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * 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.
+ *
+ */
+
+#include <common.h>
+#include <io.h>
+#include <init.h>
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <clock.h>
+
+#define TIMER_LOAD 0x00
+#define TIMER_VALUE 0x04
+#define TIMER_CONTROL 0x08
+
+#define TIMER_CTRL_ENABLE BIT(7)
+
+/*
+ * TIMER_CONTROL_PERIODIC:
+ * The counter generates an interrupt at a constant interval,
+ * reloading the original value after wrapping past zero.
+ */
+#define TIMER_CTRL_PERIODIC BIT(6)
+
+/* interrupt enable */
+#define TIMER_CTRL_IE BIT(5)
+
+/* Prescalers */
+#define TIMER_CTRL_P1 (0 << 2)
+#define TIMER_CTRL_P16 (1 << 2)
+#define TIMER_CTRL_P256 (2 << 2)
+
+/* Counter register size is 32 Bit long */
+#define TIMER_CTRL_32BIT BIT(1)
+
+static void __iomem *timer_base;
+
+static uint64_t uemd_timer_cs_read(void)
+{
+ /* Down counter! */
+ return ~__raw_readl(timer_base + TIMER_VALUE);
+}
+
+static struct clocksource uemd_cs = {
+ .read = uemd_timer_cs_read,
+ .mask = CLOCKSOURCE_MASK(32),
+};
+
+static int uemd_timer_probe(struct device_d *dev)
+{
+ int mode;
+ struct clk *timer_clk;
+
+ /* use only one timer */
+ if (timer_base)
+ return -EBUSY;
+
+ timer_base = dev_request_mem_region(dev, 0);
+ if (!timer_base) {
+ dev_err(dev, "could not get memory region\n");
+ return -ENODEV;
+ }
+
+ timer_clk = clk_get(dev, NULL);
+ if (IS_ERR(timer_clk)) {
+ int ret = PTR_ERR(timer_clk);
+ dev_err(dev, "clock not found: %d\n", ret);
+ return ret;
+ }
+
+ /* Stop timer */
+ __raw_writel(0, timer_base + TIMER_CONTROL);
+
+ /* Setup */
+ __raw_writel(0xffffffff, timer_base + TIMER_LOAD);
+ __raw_writel(0xffffffff, timer_base + TIMER_VALUE);
+
+ mode = TIMER_CTRL_32BIT |
+ TIMER_CTRL_PERIODIC |
+ TIMER_CTRL_P1;
+ __raw_writel(mode, timer_base + TIMER_CONTROL);
+
+ /* Fire it up! */
+ mode |= TIMER_CTRL_ENABLE;
+ __raw_writel(mode, timer_base + TIMER_CONTROL);
+
+ clocks_calc_mult_shift(&uemd_cs.mult, &uemd_cs.shift,
+ clk_get_rate(timer_clk), NSEC_PER_SEC, 10);
+
+ init_clock(&uemd_cs);
+
+ return 0;
+}
+
+static __maybe_unused struct of_device_id uemd_timer_dt_ids[] = {
+ {
+ .compatible = "module,uemd-timer",
+ }, {
+ /* sentinel */
+ }
+};
+
+static struct driver_d uemd_timer_driver = {
+ .probe = uemd_timer_probe,
+ .name = "uemd-timer",
+ .of_compatible = DRV_OF_COMPAT(uemd_timer_dt_ids),
+};
+
+static int uemd_timer_init(void)
+{
+ return platform_driver_register(&uemd_timer_driver);
+}
+coredevice_initcall(uemd_timer_init);