Quoting Anson Huang (2018-10-15 21:37:31) > Hi, Stephen > > Anson Huang > Best Regards! > > > > -----Original Message----- > > From: Stephen Boyd <[email protected]> > > Sent: Tuesday, October 16, 2018 12:46 AM > > To: [email protected]; [email protected]; > > [email protected]; [email protected]; > > [email protected]; [email protected]; [email protected]; > > Anson Huang <[email protected]>; Fabio Estevam > > <[email protected]>; Jerome Forissier <[email protected]>; > > Peng Fan <[email protected]>; Rob Herring <[email protected]> > > Cc: dl-linux-imx <[email protected]> > > Subject: RE: [PATCH 2/2] clk: imx: imx7d: remove clks_init_on array > > > > Quoting Anson Huang (2018-10-15 02:33:35) > > > > > > > > > > > > > > > > > > > Why can't we add clks to the op-tee node in DT's /firmware > > > > > > container? > > > > > > Then any clks in there can be turned on forever and left enabled > > > > > > by the linux driver? > > > > > > > > > > I did NOT run op-tee with Linux-next kernel before, can you advise > > > > > more? > > > > > > > > Neither have I, so I can't advise more. > > > > > > > > > And I think if op-tee has such requirement, can we have another > > > > > patch to cover it? > > > > > > > > Yes. > > > > > > > > > > > > > I believe all other i.MX platforms also have same requirements if > > > > > considering op-tee support, so I think it should be another topic, > > > > > what do you > > > > think? > > > > > > > > > > > > > I'm going to drop these patches from my review queue. Please resend > > > > them and please include the op-tee patches too. > > > > > > > > > I do NOT know how to include the op-tee patch to meet special > > > requirement, should the op-tee related patch be added later when someone > > actually add the op-tee support for i.MX7? > > > It should NOT block this patch set, do you think we can add this patch set > > first? > > > > > > > Please resend the two patches. In the commit text for the second patch, > > describe the plan to remove CLK_IS_CRITICAL from these clks by adding an > > OP-TEE device/driver to the kernel to keep these clks enabled. My > > understanding is that there isn't an OP-TEE driver right now, but these > > clks are > > used by the firmware and can't be turned off in Linux. If in the future we > > want > > to be able to turn them on and off, we'll need to add them to an OP-TEE > > device > > node and have that driver manage the clks. > > > > How that will work when a system doesn't enable the OP-TEE driver I'm not > > sure. We may need to develop some system whereby clks like this are handed > > from the clk controller to the consumer driver when it's enabled for further > > power managment, but if they're never handed off, they're kept on forever > > like > > is done here. Anyway, please resend with a note about why these are marked > > CLK_IS_CRITICAL. > > I think there is some misunderstanding here, this patch sets those critical > clocks > with CLK_IS_CRITICAL flag to let clock driver keep them always ON, as they are > critical clocks and system (Linux kernel, NOT include op-tee) can NOT run > normally > if anyone of them is OFF.
Ok it sounds like OP-TEE usage completely orthogonal here? I'll go apply these refactorings then.
