On 24/04/13 15:51, James Hogan wrote: > On 24/04/13 14:26, Catalin Marinas wrote: >> On 23 April 2013 17:06, James Hogan <james.hogan@xxxxxxxxxx> wrote: >>> It's certainly heading in that direction a lot. For this patchset I >>> could get away with dropping arch/metag/soc/*, and deal with anything >>> that really requires something like it later. >>> >>> The machine callbacks I was planning on using in future patches are: >>> * init_time() for calling into the appropriate common clock driver from >>> time_init(), prior to setting up the timer so that the right frequency >>> can be reported based on the clock hierarchy specified in DT. I guess >>> this could be made more general, allowing any enabled clock component to >>> be initialised at this time. >> >> This is driven by DT on arm64, no need for platform callback (see >> drivers/clocksource/arch_arm_timer.c). > > Right. The problem is that the frequency of the core clock in TZ1090 > (and hence the arch timer that is derived from it) isn't discoverable in > an arch generic way. I can do something similar to tegra (see > tegra_clocks_init()) to init the common clk stuff early and then do: > > node = of_find_compatible_node(NULL, NULL, "img,meta"); > clk_core = of_clk_get_by_name(node, "core"); > rate = clk_get_rate(clk_core); > > From time_init prior to setting up the arch timer, but I need a platform > callback for that. I take that back, I've just noticed commit f2f6c2556dcc432e50003bc8fa4d62d95906f149 which makes clock setup callbacks automatic using section cunningness. :-) Cheers James -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
