Gentle Ping... Anson Huang Best Regards!
> -----Original Message----- > From: Anson Huang > Sent: Monday, September 3, 2018 3:21 PM > To: Stephen Boyd <sb...@kernel.org>; ker...@pengutronix.de; > linux-arm-ker...@lists.infradead.org; linux-...@vger.kernel.org; > linux-kernel@vger.kernel.org; mturque...@baylibre.com; > s.ha...@pengutronix.de; shawn...@kernel.org; Fabio Estevam > <fabio.este...@nxp.com>; Jerome Forissier <jerome.foriss...@linaro.org>; > Peng Fan <peng....@nxp.com>; Rob Herring <r...@kernel.org> > Cc: dl-linux-imx <linux-...@nxp.com> > Subject: RE: [PATCH 2/2] clk: imx: imx7d: remove clks_init_on array > > > > Anson Huang > Best Regards! > > > > -----Original Message----- > > From: Stephen Boyd <sb...@kernel.org> > > Sent: Saturday, September 1, 2018 1:58 AM > > To: ker...@pengutronix.de; linux-arm-ker...@lists.infradead.org; > > linux-...@vger.kernel.org; linux-kernel@vger.kernel.org; > > mturque...@baylibre.com; s.ha...@pengutronix.de; > shawn...@kernel.org; > > Anson Huang <anson.hu...@nxp.com>; Fabio Estevam > > <fabio.este...@nxp.com>; Jerome Forissier > > <jerome.foriss...@linaro.org>; Peng Fan <peng....@nxp.com>; Rob > > Herring <r...@kernel.org> > > Cc: dl-linux-imx <linux-...@nxp.com> > > Subject: Re: [PATCH 2/2] clk: imx: imx7d: remove clks_init_on array > > > > Quoting Jerome Forissier (2018-08-31 01:01:44) > > > > > > > > > On 08/31/2018 03:29 AM, Stephen Boyd wrote: > > > > Quoting Peng Fan (2018-08-12 18:15:41) > > > >> Hi Anson, > > > >> > > > >>>>> -----Original Message----- > > > >>>>> From: Anson Huang > > > >>>>> Sent: 2018年8月8日 12:39 > > > >>>>> To: shawn...@kernel.org; s.ha...@pengutronix.de; > > > >>>>> ker...@pengutronix.de; Fabio Estevam <fabio.este...@nxp.com>; > > > >>>>> mturque...@baylibre.com; sb...@kernel.org; > > > >>>>> linux-arm-ker...@lists.infradead.org; > > > >>>>> linux-...@vger.kernel.org; linux-kernel@vger.kernel.org > > > >>>>> Cc: dl-linux-imx <linux-...@nxp.com> > > > >>>>> Subject: [PATCH 2/2] clk: imx: imx7d: remove clks_init_on > > > >>>>> array > > > >>>>> > > > >>>>> Clock framework will enable those clocks registered with > > > >>>>> CLK_IS_CRITICAL flag, so no need to have clks_init_on array > > > >>>>> during clock > > > >>>> initialization now. > > > >>>> > > > >>>> Will it be more flexible to parse dts saying "critical-clocks = > > > >>>> <xxx>" > > > >>>> or "init-on-arrary=<xxx>" > > > >>>> and enable those clocks? > > > >>> > > > >>> Parsing the clocks arrays from dtb is another way of enabling > > > >>> critical clocks, but for current i.MX6/7 platforms, we implement > > > >>> it in same way as most of other SoCs, currently I did NOT see > > > >>> any necessity of putting them in dtb, just adding flag during > > > >>> clock registering is more simple, if there is any special > > > >>> requirement for different clocks set to be enabled, then we can > > > >>> add support to enable > > the method of parsing critical-clocks from dtb. Just my two cents. > > > >> > > > >> Thinking about OP-TEE want to use one device, but it's clocks are > > > >> registered by Linux, because there is no module in Linux side use > > > >> it, it will shutdown the clock, which cause OP-TEE could not > > > >> access the > > device. > > > >> > > > >> Then people have to modify clk code to add CLK_IS_CRITICAL flag > > > >> to make sure the clocks are not shutdown by Linux. > > > >> > > > >> However adding a new property in clk node and let driver code > > > >> parse the dts, there is no need to modify clk driver code when > > > >> OP-TEE needs > > another device clock. > > > >> > > > > > > > > If OP-TEE needs linux to keep things on then why can't the OP-TEE > > > > driver in Linux probe, acquire clocks, and keep the clks enabled > > > > forever? > > > > > > Sounds reasonable, but how could this be done without introducing > > > platform-specific stuff in the OP-TEE driver? > > > > > > > Why is that a goal? > > I do NOT think we should consider such case in this patch series, whatever > OP-TEE needs for its own feature, it should do necessary operations either in > its > driver or somewhere else by adding new patch. > > Anson.
