Hi Nishanth, On Wednesday 14 May 2014 09:04 PM, Nishanth Menon wrote: > On Wed, May 14, 2014 at 10:19 AM, Kishon Vijay Abraham I <kis...@ti.com> > wrote: >> Hi Roger, >> >> On Wednesday 14 May 2014 06:46 PM, Roger Quadros wrote: >>> Hi Kishon, >>> >>> On 05/06/2014 04:33 PM, Kishon Vijay Abraham I wrote: >>>> APLL used by PCIE phy can either use external clock as input or the clock >>>> from DPLL. Added support for the APLL to use external clock as input here. >>>> >>>> Cc: Rajendra Nayak <rna...@ti.com> >>>> Cc: Tero Kristo <t-kri...@ti.com> >>>> Cc: Paul Walmsley <p...@pwsan.com> >>>> Signed-off-by: Kishon Vijay Abraham I <kis...@ti.com> >>>> --- >>>> Documentation/devicetree/bindings/phy/ti-phy.txt | 4 ++ >>>> drivers/phy/phy-ti-pipe3.c | 75 >>>> ++++++++++++++-------- >>>> 2 files changed, 52 insertions(+), 27 deletions(-) >>>> >>>> diff --git a/Documentation/devicetree/bindings/phy/ti-phy.txt >>>> b/Documentation/devicetree/bindings/phy/ti-phy.txt >>>> index bc9afb5..d50f8ee 100644 >>>> --- a/Documentation/devicetree/bindings/phy/ti-phy.txt >>>> +++ b/Documentation/devicetree/bindings/phy/ti-phy.txt >>>> @@ -76,6 +76,10 @@ Required properties: >>>> * "dpll_ref_m2" - external dpll ref clk >>>> * "phy-div" - divider for apll >>>> * "div-clk" - apll clock >>>> + * "apll_mux" - mux for pcie apll >>>> + * "refclk_ext" - external reference clock for pcie apll >>>> + - ti,ext-clk: To specifiy if PCIE apll should use external clock. >>>> Applicable >>>> + only to PCIE PHY. >>> >>> Instead of specifying both clock sources "dpll_ref_clock", "refclk_ext" and >>> then specifying a 3rd control option "ti,ext-clk" to select one of the 2 >>> sources, why can't the DT just supply one clock source, i.e. the one that >>> is being used in the board instance? The driver should then just configure >>> the clock rate that is needed at that node. Shouldn't the clock framework >>> automatically take care of muxing and parent rates? >> >> Want the dt to have all the clocks used by the controller. "ti,ext-clk" >> should >> go in the board dt file (suggested by Nishanth). >> The point is at some point later if some one wants to change the clock >> source, >> it should be a simple enabling "ti,ext-clk" flag instead of finding the clock >> phandle etc.. > > Wonder if that is implicit by the presence of "refclk_ext" in the > clocks provided?
IMO the presence of "refclk_ext" is useless unless the board indicates it provides the clock source. refclk_ext holds phandle for *fixed-clock*, so irrespective of whether the board provides a clock or not, it can have that handle for configuring in PRCM. However if the board does not provide the clock source, configuring refclk_ext in PRCM is useless. Thanks Kishon -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html