From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-wg0-f41.google.com ([74.125.82.41]) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1TN2Hr-0005oy-Jp for barebox@lists.infradead.org; Sat, 13 Oct 2012 14:01:56 +0000 Received: by mail-wg0-f41.google.com with SMTP id ds1so21430wgb.0 for ; Sat, 13 Oct 2012 07:01:49 -0700 (PDT) From: Carlo Caione Date: Sat, 13 Oct 2012 16:00:12 +0200 Message-Id: <1350136816-33529-2-git-send-email-carlo.caione@gmail.com> In-Reply-To: <1350136816-33529-1-git-send-email-carlo.caione@gmail.com> References: <1350136816-33529-1-git-send-email-carlo.caione@gmail.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: barebox-bounces@lists.infradead.org Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: [PATCH 1/5] BCM2835: add clocksource driver To: barebox@lists.infradead.org Signed-off-by: Carlo Caione --- 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 + * + * 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 +#include +#include +#include +#include +#include +#include +#include + +/* 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 _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox