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From: Carlo Caione <carlo.caione@gmail.com>
To: barebox@lists.infradead.org
Subject: [PATCH 1/5] BCM2835: add clocksource driver
Date: Sat, 13 Oct 2012 13:22:57 +0200	[thread overview]
Message-ID: <1350127381-21312-2-git-send-email-carlo.caione@gmail.com> (raw)
In-Reply-To: <1350127381-21312-1-git-send-email-carlo.caione@gmail.com>

Signed-off-by: Carlo Caione <carlo.caione@gmail.com>
---
 drivers/clocksource/Kconfig   |  4 ++
 drivers/clocksource/Makefile  |  1 +
 drivers/clocksource/bcm2835.c | 95 +++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 100 insertions(+)
 create mode 100644 drivers/clocksource/bcm2835.c

diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index 9d6d293..09acdd7 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -2,6 +2,10 @@ config ARM_SMP_TWD
 	bool
 	depends on ARM && CPU_V7
 
+config CLOCKSOURCE_BCM2835
+	bool
+	depends on ARCH_BCM2835
+
 config CLOCKSOURCE_NOMADIK
 	bool
 	depends on ARM
diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index bef465c..92d7c13 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -1,2 +1,3 @@
 obj-$(CONFIG_ARM_SMP_TWD) += arm_smp_twd.o
+obj-$(CONFIG_CLOCKSOURCE_BCM2835) += bcm2835.o
 obj-$(CONFIG_CLOCKSOURCE_NOMADIK) += nomadik.o
diff --git a/drivers/clocksource/bcm2835.c b/drivers/clocksource/bcm2835.c
new file mode 100644
index 0000000..78f0cae
--- /dev/null
+++ b/drivers/clocksource/bcm2835.c
@@ -0,0 +1,95 @@
+/*
+ * Author: Carlo Caione <carlo@carlocaione.org>
+ *
+ * Based on clocksource for nomadik
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * 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, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ *
+ */
+
+
+#include <common.h>
+#include <clock.h>
+#include <io.h>
+#include <init.h>
+#include <driver.h>
+#include <errno.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+
+/* Registers */
+#define ST_CLO	0x04
+
+static __iomem void *stc_base;
+
+static uint64_t stc_read_cycles(void)
+{
+	return readl(stc_base + ST_CLO);
+}
+
+static struct clocksource bcm2835_stc = {
+	.read = stc_read_cycles,
+	.mask = CLOCKSOURCE_MASK(32),
+};
+
+static int bcm2835_cs_probe(struct device_d *dev)
+{
+	static struct clk *stc_clk;
+	u32 rate;
+	int ret;
+
+	stc_clk = clk_get(dev, NULL);
+	if (IS_ERR(stc_clk)) {
+		ret = PTR_ERR(stc_clk);
+		dev_err(dev, "clock not found: %d\n", ret);
+		return ret;
+	}
+
+	ret = clk_enable(stc_clk);
+	if (ret) {
+		dev_err(dev, "clock failed to enable: %d\n", ret);
+		clk_put(stc_clk);
+		return ret;
+	}
+
+	rate = clk_get_rate(stc_clk);
+	stc_base = dev_request_mem_region(dev, 0);
+
+	clocks_calc_mult_shift(&bcm2835_stc.mult, &bcm2835_stc.shift, rate, NSEC_PER_SEC, 60);
+	init_clock(&bcm2835_stc);
+
+	return 0;
+}
+
+static __maybe_unused struct of_device_id bcm2835_cs_dt_ids[] = {
+	{
+			.compatible = "bcm,bcm2835-cs",
+	}, {
+			/* sentinel */
+	}
+};
+
+static struct driver_d bcm2835_cs_driver = {
+	.name = "bcm2835-cs",
+	.probe = bcm2835_cs_probe,
+	.of_compatible = DRV_OF_COMPAT(bcm2835_cs_dt_ids),
+};
+
+static int bcm2835_cs_init(void)
+{
+	return platform_driver_register(&bcm2835_cs_driver);
+}
+coredevice_initcall(bcm2835_cs_init);
-- 
1.7.12.3


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  reply	other threads:[~2012-10-13 11:23 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-10-13 11:22 [PATCH 0/5] BCM2835/Raspberry-Pi Carlo Caione
2012-10-13 11:22 ` Carlo Caione [this message]
2012-10-13 11:22 ` [PATCH 2/5] BCM2835: add gpio driver Carlo Caione
2012-10-13 11:22 ` [PATCH 3/5] ARM1176: add support Carlo Caione
2012-10-13 11:23 ` [PATCH 4/5] BCM2835: add support (arch) Carlo Caione
2012-10-13 11:23 ` [PATCH 5/5] Raspberry-Pi: add support (board) Carlo Caione
2012-10-13 12:16   ` Jean-Christophe PLAGNIOL-VILLARD
2012-10-13 14:00 [PATCH 0/5] BCM2835/Raspberry-Pi support Carlo Caione
2012-10-13 14:00 ` [PATCH 1/5] BCM2835: add clocksource driver Carlo Caione
2012-10-16 18:04 [PATCH 0/5] BCM2835/Raspberry-Pi support Carlo Caione
2012-10-16 18:04 ` [PATCH 1/5] BCM2835: add clocksource driver Carlo Caione
2012-10-18 19:42 [PATCH 0/5] BCM2835/Raspberry-Pi support Carlo Caione
2012-10-18 19:42 ` [PATCH 1/5] BCM2835: add clocksource driver Carlo Caione

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