From mboxrd@z Thu Jan 1 00:00:00 1970 From: James Liao Subject: Re: [PATCH v7 4/9] clk: mediatek: Add MT2701 clock support Date: Tue, 10 May 2016 10:30:35 +0800 Message-ID: <1462847435.23126.10.camel@mtksdaap41> References: <1460621514-65191-1-git-send-email-jamesjj.liao@mediatek.com> <1460621514-65191-5-git-send-email-jamesjj.liao@mediatek.com> <20160506231151.GI3492@codeaurora.org> <1462775888.5344.20.camel@mtksdaap41> <20160509222950.GV3492@codeaurora.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20160509222950.GV3492@codeaurora.org> Sender: linux-clk-owner@vger.kernel.org To: Stephen Boyd Cc: Matthias Brugger , Mike Turquette , Rob Herring , John Crispin , Arnd Bergmann , Sascha Hauer , Daniel Kurtz , Philipp Zabel , devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mediatek@lists.infradead.org, linux-clk@vger.kernel.org, srv_heupstream@mediatek.com, Shunli Wang List-Id: devicetree@vger.kernel.org Hi Stephen, On Mon, 2016-05-09 at 15:29 -0700, Stephen Boyd wrote: > On 05/09, James Liao wrote: > > On Fri, 2016-05-06 at 16:11 -0700, Stephen Boyd wrote: > > > On 04/14, James Liao wrote: > > > > diff --git a/drivers/clk/mediatek/clk-mt2701.c b/drivers/clk/mediatek/clk-mt2701.c > > > > new file mode 100644 > > > > index 0000000..b4db141 > > > > --- /dev/null > > > > +++ b/drivers/clk/mediatek/clk-mt2701.c > > > > +static void __init mtk_infrasys_init(struct device_node *node) > > > > +{ > > > > + struct clk_onecell_data *clk_data; > > > > + int r; > > > > + > > > > + clk_data = mtk_alloc_clk_data(CLK_INFRA_NR); > > > > + > > > > + mtk_clk_register_gates(node, infra_clks, ARRAY_SIZE(infra_clks), > > > > + clk_data); > > > > + mtk_clk_register_factors(infra_fixed_divs, ARRAY_SIZE(infra_fixed_divs), > > > > + clk_data); > > > > + > > > > + r = of_clk_add_provider(node, of_clk_src_onecell_get, clk_data); > > > > + if (r) > > > > + pr_err("%s(): could not register clock provider: %d\n", > > > > + __func__, r); > > > > +} > > > > +CLK_OF_DECLARE(mtk_infrasys, "mediatek,mt2701-infracfg", mtk_infrasys_init); > > > > > > I'm still lost on the usage of CLK_OF_DECLARE here. What part of > > > these clk controllers needs to be registered to make the timer > > > work? > > > > GPT (mtk-timer.c) may need infracfg and topckgen clocks. MT8173 for > > example: > > > > timer: timer@10008000 { > > [...] > > clocks = <&infracfg CLK_INFRA_CLK_13M>, > > <&topckgen CLK_TOP_RTC_SEL>; > > }; > > Ok. It should be possible to only register the clk tree for these > clks in CLK_OF_DECLARE() and then register the other clks that > the clk provider provides with a regular driver probe routine. > That way we can get the advantage of the device framework, etc. > but still register the clks we need to make the timer work early > on. I'll study a new way to separate clock registration of a subsystem into CLK_OF_DECLARE() and device probe(). > > > > > > + GATE_DISP1(CLK_MM_DPI_DIGL, "mm_dpi_digl", "dpi0_sel", 2), > > > > + GATE_DISP1(CLK_MM_DPI_ENGINE, "mm_dpi_eng", "mm_sel", 3), > > > > + GATE_DISP1(CLK_MM_DPI1_DIGL, "mm_dpi1_digl", "dpi1_sel", 4), > > > > + GATE_DISP1(CLK_MM_DPI1_ENGINE, "mm_dpi1_eng", "mm_sel", 5), > > > > + GATE_DISP1(CLK_MM_TVE_OUTPUT, "mm_tve_output", "tve_sel", 6), > > > > + GATE_DISP1(CLK_MM_TVE_INPUT, "mm_tve_input", "dpi0_sel", 7), > > > > + GATE_DISP1(CLK_MM_HDMI_PIXEL, "mm_hdmi_pixel", "dpi1_sel", 8), > > > > + GATE_DISP1(CLK_MM_HDMI_PLL, "mm_hdmi_pll", "hdmi_sel", 9), > > > > + GATE_DISP1(CLK_MM_HDMI_AUDIO, "mm_hdmi_audio", "apll_sel", 10), > > > > + GATE_DISP1(CLK_MM_HDMI_SPDIF, "mm_hdmi_spdif", "apll_sel", 11), > > > > + GATE_DISP1(CLK_MM_TVE_FMM, "mm_tve_fmm", "mm_sel", 14), > > > > +}; > > > > > > I also don't understand why we don't have different files and > > > drivers for all these different clock controllers? They all have > > > a similar probe structure, sure, but otherwise these are > > > different devices with different clks for them. The whole #ifdef > > > thing in the later patch would go away too. > > > > Yes, you are right. So you prefer to support subsystem clocks in > > separated files such as clk-mt2701-mm.c, clk-mt2701-bdp.c and so on, > > right? > > > > But even if we implement subsystem clock in separated files, we still > > need a way to make them optional. So the config options and #ifdef may > > not be removed. > > Presumably different files could just not be compiled if the > config is disabled, thus removing any need for #ifdef. OK. I'll try to implement these subsystem clocks into separated files in next patch. > > > > > > + GATE_BDP1(CLK_BDP_BRG_RT_B, "brg_rt_bclk", "mm_sel", 12), > > > > + GATE_BDP1(CLK_BDP_BRG_RT_DRAM, "brg_rt_dram", "mm_sel", 13), > > > > + GATE_BDP1(CLK_BDP_LARBRT_DRAM, "larbrt_dram", "mm_sel", 14), > > > > + GATE_BDP1(CLK_BDP_TMDS_SYN, "tmds_syn", "hdmi_0_pll340m", 15), > > > > + GATE_BDP1(CLK_BDP_HDMI_MON, "hdmi_mon", "hdmi_0_pll340m", 16), > > > > +}; > > > > + > > > > +static void __init mtk_bdpsys_init(struct device_node *node) > > > > > > Shouldn't be __init because it's driver probe path. > > > > I use builtin_platform_driver_probe(clk_drv, clk_probe) to register this > > driver, and it looks can be __init. > > Ok, but that doesn't work with deferred probe right? It may be > better to avoid it then. It may be a concern. I'll investigate a proper way to implement the init functions. Best regards, James