From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chanwoo Choi Subject: Re: [PATCH 11/19] clk: samsung: exynos5433: Add clocks for CMU_BUS{0|1|2} domains Date: Thu, 27 Nov 2014 21:58:53 +0900 Message-ID: <5477200D.5030706@samsung.com> References: <1417073716-22997-1-git-send-email-cw00.choi@samsung.com> <54771173.6090408@samsung.com> <54771518.1010004@samsung.com> <3556463.Me1EFEY7Zb@wuerfel> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-reply-to: <3556463.Me1EFEY7Zb@wuerfel> Sender: linux-samsung-soc-owner@vger.kernel.org To: Arnd Bergmann Cc: Sylwester Nawrocki , linux-samsung-soc@vger.kernel.org, linux-kernel@vger.kernel.org, kgene.kim@samsung.com, mark.rutland@arm.com, olof@lixom.net, catalin.marinas@arm.com, will.deacon@arm.com, tomasz.figa@gmail.com, thomas.abraham@linaro.org, linus.walleij@linaro.org, kyungmin.park@samsung.com, inki.dae@samsung.com, chanho61.park@samsung.com, geunsik.lim@samsung.com, sw0312.kim@samsung.com, jh80.chung@samsung.com, a.kesavan@samsung.com, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org List-Id: devicetree@vger.kernel.org Dear Arnd, On 11/27/2014 09:35 PM, Arnd Bergmann wrote: > On Thursday 27 November 2014 13:12:08 Sylwester Nawrocki wrote: >> On 27/11/14 12:56, Chanwoo Choi wrote: >>> On 11/27/2014 08:41 PM, Arnd Bergmann wrote: >>>>> On Thursday 27 November 2014 16:35:08 Chanwoo Choi wrote: >>>>>>> + - "samsung,exynos5433-cmu-bus0", "samsung,exynos5433-cmu-bus1" >>>>>>> + and "samsung,exynos5433-cmu-bus2" - clock controller compatible for CMU_BUS >>>>>>> + which generates global data buses clock and global peripheral buses clock. >>>>>>> >>>>>>> - reg: physical base address of the controller and length of memory mapped >>>>>>> region. >>>>>>> >>>>> >>>>> This looks like you are duplicating the bindings and the code, but >>>>> it's really the same hardware multiple times with minor variations >>>>> that you should be able to describe properly here. Why not make >>>>> three nodes with the same compatible string and have them handled >>>>> by the same code? >>> >>> Each CMU_BUSx domain of Exynos5433 have different base address as following: >>> - CMU_BUS0's base address and range : 0x1360_0000 ~ 0x1360_0b04 >>> - CMU_BUS1's base address and range : 0x1480_0000 ~ 0x1480_0b04 >>> - CMU_BUS2's base address and range : 0x1340_0000 ~ 0x1340_0b04 >>> >>> So, I implement CMU_BUSx domain which has each compatible string. > > But the base address is in the reg property, not in the compatible > property. What I mean is to have multiple nodes like The merged clock driver in mainline have different compatible string if base addresss of clock domain is different. So, I implemented each CMU_BUSx domain with different compatible string. > > clock-controller@113600000 { > reg = <0 0x113600000 0 0x1000>; > compatible = "samsung,exynos5433-cmu"; > #clock-cells = <1>; > }; > > clock-controller@114800000 { > reg = <0 0x114800000 0 0x1000>; > compatible = "samsung,exynos5433-cmu"; > #clock-cells = <1>; > }; > > The code will just map the local registers for each instance and then > provide the clocks of the right instance when asked for it. Each clock domain has not the same mux/divider/clock. So, just one compatible string could not support all of clock domains. Best Regards, Chanwoo Choi > >> You can always have multiple entries in the reg property. I've done >> something like this for the exynos4415 CMU_ISPx units: >> >> cmu_isp: clock-controller@12060000 { >> compatible = "samsung,exynos4415-cmu-isp"; >> reg = <0x12060000 0xB10>, <0x12070000 0xB10>; >> #clock-cells = <1>; >> >> assigned-clocks = <&cmu CLK_FOUT_ISP_PLL>; >> assigned-clock-rates = <300000000>; >> }; > > This is a different problem, this is a clock controller with multiple > sets of registers that are all different. In case of the cmu, it seems > that they are all the same, you just have multiple copies at different > locations, and they are connected to different devices. > > Arnd > -- > To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >