Messages in this thread | | | Date | Fri, 5 Apr 2013 20:56:05 +0300 | From | Grygorii Strashko <> | Subject | Re: [RFC][PATCH 1/2] ARM: OMAP4: clock: Add device tree support for AUXCLKs |
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On 04/04/2013 07:41 PM, Tony Lindgren wrote: > * Roger Quadros <rogerq@ti.com> [130404 00:39]: >> On 04/04/2013 02:42 AM, Tony Lindgren wrote: >>>> --- a/arch/arm/mach-omap2/cclock44xx_data.c >>>> +++ b/arch/arm/mach-omap2/cclock44xx_data.c >>>> @@ -27,6 +27,7 @@ >>>> #include <linux/clk-private.h> >>>> #include <linux/clkdev.h> >>>> #include <linux/io.h> >>>> +#include <linux/of.h> >>>> >>>> #include "soc.h" >>>> #include "iomap.h" >>>> @@ -1663,6 +1664,40 @@ static struct omap_clk omap44xx_clks[] = { >>>> CLK(NULL, "cpufreq_ck", &dpll_mpu_ck, CK_443X), >>>> }; >>>> >>>> +static struct clk *scrm_clks[] = { >>>> + &auxclk0_ck, >>>> + &auxclk1_ck, >>>> + &auxclk2_ck, >>>> + &auxclk3_ck, >>>> + &auxclk4_ck, >>>> + &auxclk5_ck, >>>> +}; >>> Hmm I don't like the idea of specifying the auxclk both in the >>> cclock44xx_data.c and in DT.. >> Right, but till we have all clocks moved to DT we only need this >> approach for general purpose clocks that are not mapped to devices >> by hwmod. > For v3.10, let's just make sure that USB works with DT as then > after v3.10 we can make omap4 DT only and get rid of estimated > 7K lines of code and data. I guess this is the last piece missing > for that, or are we also missing something else? > > Can't you set up a clock alias for your device so it can find the > auxclk when requesting it with the dev entry? > > For the DT clock driver if needed for v3.10, how about just do a > minimal drivers/clock/omap/ that uses the standard binding? > Then that driver can just do clk_get() from cclock44xx_data.c > for now? And then later on we'll just move all the clocks to a > combination of DT + /lib/firmware. > Hi Roger, Rajendra, All
Sorry that disturbing you.
I'm supporting Android OMAP4 kernels (K3.0/K3.4) and like to clarify few points regarding this approach (having into account possible future migrations on newer Kernels and OMAP5). If I understand everything right, this patch series allows to create clock binding in DT using following syntax: clocks = <&aux_clks 3> - does it means that in worst case there will be ~200 clock IDs defined? - does it means that clock nodes binding using phandles (human-friendly notation) isn't going to be supported? for example: clocks = <&sys_clkin_ck> clocks = <&dss_sys_clk &dss_tv_clk &dss_dss_clk>)
I was horrified to think about the problems of this approach support (in case if there would be more then ~30 IDs) - just miss with on digit and weeks of debugging would be guaranteed.
Please, say me that i'm wrong. And why clock DT data can't be auto-generated like all other OMAP data to close this questions?
Thanks.
>> e.g. auxclk are required to be specified in DT nodes for USB PHY. >> Without this we can't get USB host working on Panda. > OK. So if the USB PHY has a dev entry, can't you just set up a > clock alias in struct omap_clk omap44xx_clks[] for it? > >> As Rajendra points out, it seems moving entire clock data to DT is not >> going to happen soon. So this is the simplistic way things can work. > Right but seems like we can get started there without moving > them all at once. > > Regards, > > Tony > -- > To unsubscribe from this list: send the line "unsubscribe linux-omap" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html
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