From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tero Kristo Subject: Re: [PATCHv9 30/43] ARM: dts: am33xx clock data Date: Sat, 26 Oct 2013 15:46:26 +0300 Message-ID: <526BB9A2.2050108@ti.com> References: <1382716658-6964-1-git-send-email-t-kristo@ti.com> <1382716658-6964-31-git-send-email-t-kristo@ti.com> <1382747784.6200.4.camel@polaris.local> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8"; Format="flowed" Content-Transfer-Encoding: base64 Return-path: In-Reply-To: <1382747784.6200.4.camel@polaris.local> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: =?UTF-8?B?SmFuIEzDvGJiZQ==?= Cc: nm@ti.com, devicetree@vger.kernel.org, paul@pwsan.com, mturquette@linaro.org, tony@atomide.com, rnayak@ti.com, bcousson@baylibre.com, linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org List-Id: linux-omap@vger.kernel.org T24gMTAvMjYvMjAxMyAwMzozNiBBTSwgSmFuIEzDvGJiZSB3cm90ZToKPiBPbiBGcmksIDIwMTMt MTAtMjUgYXQgMTg6NTcgKzAzMDAsIFRlcm8gS3Jpc3RvIHdyb3RlOgo+PiArICAgICAgIG1jYXNw MF9mY2s6IG1jYXNwMF9mY2sgewo+PiArICAgICAgICAgICAgICAgI2Nsb2NrLWNlbGxzID0gPDA+ Owo+PiArICAgICAgICAgICAgICAgY29tcGF0aWJsZSA9ICJmaXhlZC1mYWN0b3ItY2xvY2siOwo+ PiArICAgICAgICAgICAgICAgY2xvY2tzID0gPCZzeXNfY2xraW5fY2s+Owo+PiArICAgICAgICAg ICAgICAgY2xvY2stbXVsdCA9IDwxPjsKPj4gKyAgICAgICAgICAgICAgIGNsb2NrLWRpdiA9IDwx PjsKPj4gKyAgICAgICB9Owo+PiArCj4+ICsgICAgICAgbWNhc3AxX2ZjazogbWNhc3AxX2ZjayB7 Cj4+ICsgICAgICAgICAgICAgICAjY2xvY2stY2VsbHMgPSA8MD47Cj4+ICsgICAgICAgICAgICAg ICBjb21wYXRpYmxlID0gImZpeGVkLWZhY3Rvci1jbG9jayI7Cj4+ICsgICAgICAgICAgICAgICBj bG9ja3MgPSA8JnN5c19jbGtpbl9jaz47Cj4+ICsgICAgICAgICAgICAgICBjbG9jay1tdWx0ID0g PDE+Owo+PiArICAgICAgICAgICAgICAgY2xvY2stZGl2ID0gPDE+Owo+PiArICAgICAgIH07Cj4K PiBXaGF0IGlzIHlvdSB1c2UgY2FzZSBmb3IgdGhlc2UgY2xvY2tzIHdpdGggYSBmaXhlZCBmYWN0 b3Igb2YgMT8gV291bGRuJ3QKPiBpdCBiZSBzaW1wbGVyIHRvIGp1c3QgdXNlIHN5c19jbGtpbl9j ayBmcm9tIHRoZSBkZXZpY2VzPwoKVGhpcyBpcyBqdXN0IGtpbmQgb2YgYSBkdW1teSBjbG9jayBu b2RlIGZvciB0aGUgZHJpdmVyIHVzZSwgc28gdGhhdCBpdCAKaXMgc2ltcGxlciBmb3IgdGhlbSB0 byBmaW5kIHRoZWlyIGNsb2Nrcy4gSWYgdGhlc2UgYXJlIGRyb3BwZWQsIHRoZSAKZHJpdmVycyBu ZWVkIHRvIGtub3cgdGhhdCBpbnN0ZWFkIG9mIHRoZWlyIG9sZCBvd24gbWNhc3BYX2ZjaywgdGhl eSBub3cgCm5lZWQgdG8gZGlyZWN0bHkgY29ubmVjdCB0byBzeXNfY2xraW5fY2suIFRoaXMgYWxz byBhbGxvd3MgdG8gdHJhY2sgCnVzZWNvdW50cyBmb3IgdGhlIGNsb2NrcyBiZXR0ZXIsIGlmIHlv dSBkb24ndCBoYXZlIHRoZSBtY2FzcFhfZmNrOnMgZm9yIApleGFtcGxlLCB5b3Ugd2lsbCBqdXN0 IGhhdmUgYSB1c2Vjb3VudCBvZiAyNSBmb3IgdGhlIHN5c19jbGtpbl9jaywgYnV0IApkb24ndCBy ZWFsbHkga25vdyB3aG8gaXMgdXNpbmcgaXQuIEFsc28sIG90aGVyIFNvQ3MgbW9zdCBsaWtlbHkg aGF2ZSB0aGUgCnNhbWUgbmFtZSBpbiB1c2UsIHNvIGp1c3QgdG8ga2VlcCB0aGUgY2xvY2sgZGF0 YSBjb21wYXRpYmxlIGFjcm9zcyBTb0NzLgoKVGhlc2UgZmlsZXMgYXJlIGFsc28gY29tcGxldGVs eSBhdXRvZ2VuZXJhdGVkIGZyb20gdGhlIGV4aXN0aW5nIGNsb2NrIApkYXRhIHVuZGVyIG1hY2gt b21hcDIsIGFuZCB0aGVzZSBub2RlcyBleGlzdCB0aGVyZS4KCkJ1dCB5ZWEsIG5vIGhhcmQgcmVx dWlyZW1lbnQuCgotVGVybwoKCl9fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fCmxpbnV4LWFybS1rZXJuZWwgbWFpbGluZyBsaXN0CmxpbnV4LWFybS1rZXJuZWxA bGlzdHMuaW5mcmFkZWFkLm9yZwpodHRwOi8vbGlzdHMuaW5mcmFkZWFkLm9yZy9tYWlsbWFuL2xp c3RpbmZvL2xpbnV4LWFybS1rZXJuZWwK From mboxrd@z Thu Jan 1 00:00:00 1970 From: t-kristo@ti.com (Tero Kristo) Date: Sat, 26 Oct 2013 15:46:26 +0300 Subject: [PATCHv9 30/43] ARM: dts: am33xx clock data In-Reply-To: <1382747784.6200.4.camel@polaris.local> References: <1382716658-6964-1-git-send-email-t-kristo@ti.com> <1382716658-6964-31-git-send-email-t-kristo@ti.com> <1382747784.6200.4.camel@polaris.local> Message-ID: <526BB9A2.2050108@ti.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 10/26/2013 03:36 AM, Jan L?bbe wrote: > On Fri, 2013-10-25 at 18:57 +0300, Tero Kristo wrote: >> + mcasp0_fck: mcasp0_fck { >> + #clock-cells = <0>; >> + compatible = "fixed-factor-clock"; >> + clocks = <&sys_clkin_ck>; >> + clock-mult = <1>; >> + clock-div = <1>; >> + }; >> + >> + mcasp1_fck: mcasp1_fck { >> + #clock-cells = <0>; >> + compatible = "fixed-factor-clock"; >> + clocks = <&sys_clkin_ck>; >> + clock-mult = <1>; >> + clock-div = <1>; >> + }; > > What is you use case for these clocks with a fixed factor of 1? Wouldn't > it be simpler to just use sys_clkin_ck from the devices? This is just kind of a dummy clock node for the driver use, so that it is simpler for them to find their clocks. If these are dropped, the drivers need to know that instead of their old own mcaspX_fck, they now need to directly connect to sys_clkin_ck. This also allows to track usecounts for the clocks better, if you don't have the mcaspX_fck:s for example, you will just have a usecount of 25 for the sys_clkin_ck, but don't really know who is using it. Also, other SoCs most likely have the same name in use, so just to keep the clock data compatible across SoCs. These files are also completely autogenerated from the existing clock data under mach-omap2, and these nodes exist there. But yea, no hard requirement. -Tero