From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jon Hunter Subject: [PATCH 2/2] ARM: OMAP2+: Add device-tree support for 32kHz counter Date: Wed, 17 Oct 2012 13:33:23 -0500 Message-ID: <1350498803-22150-3-git-send-email-jon-hunter@ti.com> References: <1350498803-22150-1-git-send-email-jon-hunter@ti.com> Mime-Version: 1.0 Content-Type: text/plain Return-path: In-Reply-To: <1350498803-22150-1-git-send-email-jon-hunter@ti.com> Sender: linux-omap-owner@vger.kernel.org To: Benoit Cousson , Tony Lindgren , Rob Herring , Grant Likely Cc: device-tree , linux-omap , linux-arm , Jon Hunter List-Id: devicetree@vger.kernel.org For OMAP devices, the 32kHz counter is the default clock-source for the kernel. However, this is not the only possible clock-source the kernel can use for OMAP devices. When booting with device-tree, if the 32kHz counter is the desired clock-source for the kernel, then parse the device-tree blob to ensure that the counter is present and if so map memory for the counter using the device-tree of_iomap() function so we are no longer reliant on the OMAP HWMOD framework to do this for us. Signed-off-by: Jon Hunter --- arch/arm/mach-omap2/timer.c | 28 +++++++++++++++++++++++++++- 1 file changed, 27 insertions(+), 1 deletion(-) diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c index d064afd..a67688f 100644 --- a/arch/arm/mach-omap2/timer.c +++ b/arch/arm/mach-omap2/timer.c @@ -159,6 +159,11 @@ static struct of_device_id omap_timer_match[] __initdata = { { } }; +static struct of_device_id omap_counter_match[] __initdata = { + { .compatible = "ti,omap-counter32k", }, + { } +}; + /** * omap_get_timer_dt - get a timer using device-tree * @match - device-tree match structure for matching a device type @@ -378,11 +383,26 @@ static u32 notrace dmtimer_read_sched_clock(void) static int __init omap2_sync32k_clocksource_init(void) { int ret; + struct device_node *np = NULL; struct omap_hwmod *oh; void __iomem *vbase; const char *oh_name = "counter_32k"; /* + * If device-tree is present, then search the DT blob + * to see if the 32kHz counter is supported. + */ + if (of_have_populated_dt()) { + np = omap_get_timer_dt(omap_counter_match, NULL); + if (!np) + return -ENODEV; + + of_property_read_string_index(np, "ti,hwmods", 0, &oh_name); + if (!oh_name) + return -ENODEV; + } + + /* * First check hwmod data is available for sync32k counter */ oh = omap_hwmod_lookup(oh_name); @@ -391,7 +411,13 @@ static int __init omap2_sync32k_clocksource_init(void) omap_hwmod_setup_one(oh_name); - vbase = omap_hwmod_get_mpu_rt_va(oh); + if (of_have_populated_dt()) { + vbase = of_iomap(np, 0); + of_node_put(np); + } else { + vbase = omap_hwmod_get_mpu_rt_va(oh); + } + if (!vbase) { pr_warn("%s: failed to get counter_32k resource\n", __func__); return -ENXIO; -- 1.7.9.5