| Message ID | 1521168778-27236-41-git-send-email-david@lechnology.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Friday 16 March 2018 08:22 AM, David Lechner wrote: > +static int __init of_davinci_timer_init(struct device_node *np) > +{ > + struct clk *clk; > + > + clk = of_clk_get(np, 0); > + if (IS_ERR(clk)) { > + struct of_phandle_args clkspec; > + > + /* > + * Fall back to using ref_clk if the actual clock is not > + * available. This currently always happens because platform > + * clocks (i.e PLLs and PSCs) are registered as platform > + * devices and therefore are not available at this point in > + * the boot process. It seems to me that this is not going to be a temporary problem (or at least will be around for quite a while). So, I think we can as well just look for ref_clk directly. > + */ > + clkspec.np = of_find_node_by_name(NULL, "ref_clk"); > + if (IS_ERR(clkspec.np)) { > + pr_err("%s: No clock available for timer!\n", __func__); > + return PTR_ERR(clkspec.np); > + } > + clk = of_clk_get_from_provider(&clkspec); > + of_node_put(clkspec.np); > + } > + > + davinci_timer_init(clk); > + > + return 0; > +} > +TIMER_OF_DECLARE(davinci_timer, "ti,davinci-timer", of_davinci_timer_init); Here, I think we should use "ti,da850-timer" so we can change the fixed clock we are looking for based on the SoC. At a minimum, we should have "ti,da850-timer" in the DT along with "ti,davinci-timer". BTW, I noticed that "ti,davinci-timer" is not documented. I think we need to add a binding documentation too. Thanks, Sekhar
diff --git a/arch/arm/mach-davinci/Kconfig b/arch/arm/mach-davinci/Kconfig index ba9912b..da8a039 100644 --- a/arch/arm/mach-davinci/Kconfig +++ b/arch/arm/mach-davinci/Kconfig @@ -59,6 +59,7 @@ config MACH_DA8XX_DT default y depends on ARCH_DAVINCI_DA850 select PINCTRL + select TIMER_OF help Say y here to include support for TI DaVinci DA850 based using Flattened Device Tree. More information at Documentation/devicetree diff --git a/arch/arm/mach-davinci/time.c b/arch/arm/mach-davinci/time.c index d6a78f7..590b118 100644 --- a/arch/arm/mach-davinci/time.c +++ b/arch/arm/mach-davinci/time.c @@ -17,6 +17,7 @@ #include <linux/io.h> #include <linux/clk.h> #include <linux/err.h> +#include <linux/of.h> #include <linux/platform_device.h> #include <linux/sched_clock.h> @@ -405,3 +406,33 @@ void __init davinci_timer_init(struct clk *timer_clk) for (i=0; i< ARRAY_SIZE(timers); i++) timer32_config(&timers[i]); } + +static int __init of_davinci_timer_init(struct device_node *np) +{ + struct clk *clk; + + clk = of_clk_get(np, 0); + if (IS_ERR(clk)) { + struct of_phandle_args clkspec; + + /* + * Fall back to using ref_clk if the actual clock is not + * available. This currently always happens because platform + * clocks (i.e PLLs and PSCs) are registered as platform + * devices and therefore are not available at this point in + * the boot process. + */ + clkspec.np = of_find_node_by_name(NULL, "ref_clk"); + if (IS_ERR(clkspec.np)) { + pr_err("%s: No clock available for timer!\n", __func__); + return PTR_ERR(clkspec.np); + } + clk = of_clk_get_from_provider(&clkspec); + of_node_put(clkspec.np); + } + + davinci_timer_init(clk); + + return 0; +} +TIMER_OF_DECLARE(davinci_timer, "ti,davinci-timer", of_davinci_timer_init);
This adds device tree support to the davinci timer so that when clocks are moved to device tree, the timer will still work. Signed-off-by: David Lechner <david@lechnology.com> --- v8 changes: - none v7 changes: - add workaround for platform devices not available in early boot v6 changes: - none arch/arm/mach-davinci/Kconfig | 1 + arch/arm/mach-davinci/time.c | 31 +++++++++++++++++++++++++++++++ 2 files changed, 32 insertions(+)