Hi Claudiu, On Do, 2024-11-07 at 12:00 +0200, Claudiu Beznea wrote: > Hi, all, > > On 03.09.2024 17:48, claudiu beznea wrote: > > > > > > On 03.09.2024 16:45, Biju Das wrote: > > > Hi Claudiu, > > > > > > > -----Original Message----- > > > > From: claudiu beznea <claudiu.beznea@xxxxxxxxx> > > > > Sent: Tuesday, September 3, 2024 1:57 PM > > > > Subject: Re: [PATCH 00/16] Add initial USB support for the Renesas RZ/G3S SoC > > > > > > > > > > > > > > > > On 03.09.2024 15:37, Biju Das wrote: > > > > > > > > > > > > > > > > -----Original Message----- > > > > > > From: claudiu beznea <claudiu.beznea@xxxxxxxxx> > > > > > > Sent: Tuesday, September 3, 2024 1:26 PM > > > > > > To: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>; Ulf Hansson > > > > > > <ulf.hansson@xxxxxxxxxx> > > > > > > Cc: vkoul@xxxxxxxxxx; kishon@xxxxxxxxxx; robh@xxxxxxxxxx; > > > > > > krzk+dt@xxxxxxxxxx; conor+dt@xxxxxxxxxx; p.zabel@xxxxxxxxxxxxxx; > > > > > > geert+renesas@xxxxxxxxx; magnus.damm@xxxxxxxxx; > > > > > > gregkh@xxxxxxxxxxxxxxxxxxx; mturquette@xxxxxxxxxxxx; > > > > > > sboyd@xxxxxxxxxx; Yoshihiro Shimoda > > > > > > <yoshihiro.shimoda.uh@xxxxxxxxxxx>; > > > > > > linux-phy@xxxxxxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx; > > > > > > linux-kernel@xxxxxxxxxxxxxxx; linux- renesas-soc@xxxxxxxxxxxxxxx; > > > > > > linux-usb@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; > > > > > > linux- clk@xxxxxxxxxxxxxxx; linux-pm@xxxxxxxxxxxxxxx; Claudiu Beznea > > > > > > <claudiu.beznea.uj@xxxxxxxxxxxxxx> > > > > > > Subject: Re: [PATCH 00/16] Add initial USB support for the Renesas > > > > > > RZ/G3S SoC > > > > > > > > > > > > > > > > > > > > > > > > On 03.09.2024 15:00, Biju Das wrote: > > > > > > > > > > > > > > > > > > > > > > -----Original Message----- > > > > > > > > From: Biju Das <biju.das.jz@xxxxxxxxxxxxxx> > > > > > > > > Sent: Tuesday, September 3, 2024 12:07 PM > > > > > > > > To: Claudiu.Beznea <claudiu.beznea@xxxxxxxxx>; Ulf Hansson > > > > > > > > <ulf.hansson@xxxxxxxxxx> > > > > > > > > Cc: vkoul@xxxxxxxxxx; kishon@xxxxxxxxxx; robh@xxxxxxxxxx; > > > > > > > > krzk+dt@xxxxxxxxxx; conor+dt@xxxxxxxxxx; p.zabel@xxxxxxxxxxxxxx; > > > > > > > > geert+renesas@xxxxxxxxx; magnus.damm@xxxxxxxxx; > > > > > > > > gregkh@xxxxxxxxxxxxxxxxxxx; mturquette@xxxxxxxxxxxx; > > > > > > > > sboyd@xxxxxxxxxx; Yoshihiro Shimoda > > > > > > > > <yoshihiro.shimoda.uh@xxxxxxxxxxx>; > > > > > > > > linux-phy@xxxxxxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx; > > > > > > > > linux-kernel@xxxxxxxxxxxxxxx; linux- renesas-soc@xxxxxxxxxxxxxxx; > > > > > > > > linux-usb@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; > > > > > > > > linux- clk@xxxxxxxxxxxxxxx; linux-pm@xxxxxxxxxxxxxxx; Claudiu > > > > > > > > Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx> > > > > > > > > Subject: RE: [PATCH 00/16] Add initial USB support for the Renesas > > > > > > > > RZ/G3S SoC > > > > > > > > > > > > > > > > Hi Claudiu, > > > > > > > > > > > > > > > > > -----Original Message----- > > > > > > > > > From: claudiu beznea <claudiu.beznea@xxxxxxxxx> > > > > > > > > > Sent: Tuesday, September 3, 2024 12:00 PM > > > > > > > > > Subject: Re: [PATCH 00/16] Add initial USB support for the Renesas > > > > > > > > > RZ/G3S SoC > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > On 03.09.2024 13:31, Biju Das wrote: > > > > > > > > > > > > During boot clr USB PWR READY signal in TF-A. > > > > > > > > > > > > STR case, suspend set USB PWR READY signal in TF-A. > > > > > > > > > > > > STR case, resume clr USB PWR READY signal in TF-A. > > > > > > > > > > > As I said previously, it can be done in different ways. My point > > > > > > > > > > > was to let Linux set what it needs for all it's devices to work. > > > > > > > > > > > I think the way to go forward is a > > > > > > > > > maintainer decision. > > > > > > > > > > > > > > > > > > > > I agree, there can be n number of solution for a problem. > > > > > > > > > > > > > > > > > > > > Since you modelled system state signal (USB PWRRDY) as reset > > > > > > > > > > control signal, it is reset/DT maintainer's decision to say the > > > > > > > > > > final word whether this signal fits in reset > > > > > > > > > system framework or not? > > > > > > > > > > > > > > > > > > I was thinking: > > > > > > > > > 1/ Geert would be the best to say if he considers it OK to handle this > > > > > > > > > in Linux > > > > > > > > > > > > > > > > I agree Geert is the right person for taking SYSTEM decisions, > > > > > > > > since the signal is used only during state transitions (Table > > > > > > > > 41.6.4 AWO to ALL_ON and 41.6.3 ALL_ON to AWO) > > > > > > > > > > > > > > One more info, as per [1], this USB PWRRDY signal setting to be before Linux kernel boots. > > > > > > > > > > > > The "controlled by" column mentions CA-55 on PWRRDY signal control > > > > > > line and it is b/w steps "DDR exits from retention mode" and "clock > > > > > > start settings for system bus and peripheral modules". AFAICT, after DDR exists retention mode > > > > Linux is ready to run. > > > > > > > > > > DDR retention exit happens in TF-A and it jumps into reset code where it executes BL2 in TF_A. Bl2 > > > > checks for warm or cold reset. > > > > > If it is warm reset, it sets required minimal clocks/resets and pass > > > > > the control to linux by calling the SMC callback handler. Which in turn calls resume(step 11-->14) > > > > path. > > > > > > > > Is this from HW manual or some specific documentation? I'm referring at "resume" == "steps 11-->14" > > > > > > > > > > > > > > Step 8, Cortex-A55 Exit from DDR retention mode (when using) Setting > > > > > for exiting form DDR retention mode Step 9, Cortex-A55 USB PHY PWRRDY > > > > > signal control (if use USB) SYS_USB_PWRRDY Step 10, Cortex-A55 PCIe > > > > > RST_RSM_B signal control (if use PCIe) SYS_PCIE_RST_RSM_B > > > > > > > > Note *if use*: how does the TF-A know if USB/PCIe is used by Linux? The documentation mention to set > > > > it *if use*. Same note is on ALL_ON to VBATT transition documentation (namely "if using USB", "if > > > > using PCIe"). If TF-A will do this it should set this signals unconditionally. It will not be > > > > something wrong though. We don't know at the moment what this involves in terms of power consumption, > > > > if it means something... > > > > > > IIUC, > > > The only information we have is, > > > > > > "SYS_USB_PWRRDY and SYS_PCIE_RST_RSM_B are used when transition from ALL_ON to AWO (or from AWO to ALL_ON). > > > "When turning off USB PHY and PCIe PHY, if they are not controlled, PHY may break" > > > > > > ALL_ON to AWO_MODE state transition: > > > USB/PCIe are part of PD_ISOVCC power domain and before turning PD_ISOVCC to off, > > > we need to set USBPWRRDY signal. > > > > > > AWO_MODE to ALL_ON state transition: > > > > > > Turn on PD_ISOVCC first, then clr USBPWRRDY signal for USB usage in linux. > > > > > > Maybe we need to ask hw team, exact usage of USBPWRRDY signal other than state transition. > > > > As you may already know, this is open for quite some time and is ongoing. > > I got more clarification about the USB PWRRDY signal from the HW team. > > The conclusion is that the USB PWRRDY is a signal controlled by SYSC > controller that goes to the USB PHY and it tells the USB PHY if the power > supply is ready or not. > > In the diagram at [1] the PWRRDY signal need to be asserted/de-asserted > before/after G6, G7, G8, G9, G10 signals. > > Philipp, > > Can you please confirm that you don't want this signal to be implemented as > a reset signal to know clearly your input on it? I would like to start > looking for another approach in that case. If this is not a reset signal I don't want it to be implemented as one. regards Philipp
