| Message ID | 1404467748-12154-2-git-send-email-rogerq@ti.com |
|---|---|
| State | Accepted |
| Commit | e120fb459693bbc1ac3eabdd65c3659d7cfbfd2a |
| Headers | show |
* Roger Quadros <rogerq@ti.com> [140704 02:57]: > After clarification from the hardware team it was found that > this 1.8V PHY supply can't be switched OFF when SoC is Active. > > Since the PHY IPs don't contain isolation logic built in the design to > allow the power rail to be switched off, there is a very high risk > of IP reliability and additional leakage paths which can result in > additional power consumption. > > The only scenario where this rail can be switched off is part of Power on > reset sequencing, but it needs to be kept always-on during operation. > > This patch is required for proper functionality of USB, SATA > and PCIe on DRA7-evm. > > CC: Rajendra Nayak <rnayak@ti.com> > CC: Tero Kristo <t-kristo@ti.com> > Signed-off-by: Roger Quadros <rogerq@ti.com> Best that you queue this with the series: Acked-by: Tony Lindgren <tony@atomide.com> > --- > arch/arm/boot/dts/dra7-evm.dts | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/arch/arm/boot/dts/dra7-evm.dts b/arch/arm/boot/dts/dra7-evm.dts > index 4adc280..8308954 100644 > --- a/arch/arm/boot/dts/dra7-evm.dts > +++ b/arch/arm/boot/dts/dra7-evm.dts > @@ -240,6 +240,7 @@ > regulator-name = "ldo3"; > regulator-min-microvolt = <1800000>; > regulator-max-microvolt = <1800000>; > + regulator-always-on; > regulator-boot-on; > }; > > -- > 1.8.3.2 > -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Tony, On 07/07/2014 11:29 AM, Tony Lindgren wrote: > * Roger Quadros <rogerq@ti.com> [140704 02:57]: >> After clarification from the hardware team it was found that >> this 1.8V PHY supply can't be switched OFF when SoC is Active. >> >> Since the PHY IPs don't contain isolation logic built in the design to >> allow the power rail to be switched off, there is a very high risk >> of IP reliability and additional leakage paths which can result in >> additional power consumption. >> >> The only scenario where this rail can be switched off is part of Power on >> reset sequencing, but it needs to be kept always-on during operation. >> >> This patch is required for proper functionality of USB, SATA >> and PCIe on DRA7-evm. >> >> CC: Rajendra Nayak <rnayak@ti.com> >> CC: Tero Kristo <t-kristo@ti.com> >> Signed-off-by: Roger Quadros <rogerq@ti.com> > > Best that you queue this with the series: This patch doesn't have any dependency with the others and we're not even sure if this series will hit 3.16. But this 1V8 regulator _is_ required for normal operation of the SoC, whether the PHYs are in use or not. Can you please queue just this patch for SoC fixes for 3.16? Thanks. cheers, -roger > > Acked-by: Tony Lindgren <tony@atomide.com> > >> --- >> arch/arm/boot/dts/dra7-evm.dts | 1 + >> 1 file changed, 1 insertion(+) >> >> diff --git a/arch/arm/boot/dts/dra7-evm.dts b/arch/arm/boot/dts/dra7-evm.dts >> index 4adc280..8308954 100644 >> --- a/arch/arm/boot/dts/dra7-evm.dts >> +++ b/arch/arm/boot/dts/dra7-evm.dts >> @@ -240,6 +240,7 @@ >> regulator-name = "ldo3"; >> regulator-min-microvolt = <1800000>; >> regulator-max-microvolt = <1800000>; >> + regulator-always-on; >> regulator-boot-on; >> }; >> >> -- >> 1.8.3.2 >> -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
* Roger Quadros <rogerq@ti.com> [140707 01:36]: > Hi Tony, > > On 07/07/2014 11:29 AM, Tony Lindgren wrote: > > * Roger Quadros <rogerq@ti.com> [140704 02:57]: > >> After clarification from the hardware team it was found that > >> this 1.8V PHY supply can't be switched OFF when SoC is Active. > >> > >> Since the PHY IPs don't contain isolation logic built in the design to > >> allow the power rail to be switched off, there is a very high risk > >> of IP reliability and additional leakage paths which can result in > >> additional power consumption. > >> > >> The only scenario where this rail can be switched off is part of Power on > >> reset sequencing, but it needs to be kept always-on during operation. > >> > >> This patch is required for proper functionality of USB, SATA > >> and PCIe on DRA7-evm. > >> > >> CC: Rajendra Nayak <rnayak@ti.com> > >> CC: Tero Kristo <t-kristo@ti.com> > >> Signed-off-by: Roger Quadros <rogerq@ti.com> > > > > Best that you queue this with the series: > > This patch doesn't have any dependency with the others and we're not even sure if > this series will hit 3.16. > > But this 1V8 regulator _is_ required for normal operation of the SoC, whether the > PHYs are in use or not. > > Can you please queue just this patch for SoC fixes for 3.16? Thanks. OK will do. Regards, Tony -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/arm/boot/dts/dra7-evm.dts b/arch/arm/boot/dts/dra7-evm.dts index 4adc280..8308954 100644 --- a/arch/arm/boot/dts/dra7-evm.dts +++ b/arch/arm/boot/dts/dra7-evm.dts @@ -240,6 +240,7 @@ regulator-name = "ldo3"; regulator-min-microvolt = <1800000>; regulator-max-microvolt = <1800000>; + regulator-always-on; regulator-boot-on; };
After clarification from the hardware team it was found that this 1.8V PHY supply can't be switched OFF when SoC is Active. Since the PHY IPs don't contain isolation logic built in the design to allow the power rail to be switched off, there is a very high risk of IP reliability and additional leakage paths which can result in additional power consumption. The only scenario where this rail can be switched off is part of Power on reset sequencing, but it needs to be kept always-on during operation. This patch is required for proper functionality of USB, SATA and PCIe on DRA7-evm. CC: Rajendra Nayak <rnayak@ti.com> CC: Tero Kristo <t-kristo@ti.com> Signed-off-by: Roger Quadros <rogerq@ti.com> --- arch/arm/boot/dts/dra7-evm.dts | 1 + 1 file changed, 1 insertion(+)