| Message ID | 1524672875-14130-1-git-send-email-fabrizio.castro@bp.renesas.com |
|---|---|
| State | New |
| Headers | show |
| Series | [PATCH/RFC,v2] ARM: shmobile: defconfig: Enable LPAE | expand |
On 04/25/2018 09:14 AM, Fabrizio Castro wrote: > On iWave's iwg20m DDR1 512MB memory cannot be accessed with 32-bit > addresses, hence we need LPAE. > > Signed-off-by: Biju Das <biju.das@bp.renesas.com> > Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com> > --- > This information is mentioned in the "RZ/G Series User’s Manual: Hardware", > Chapter 2, Area Map. Is this patch going to break the functionality of other > boards? Comments welcome. LPAE is not supported by all Cortex-A class cores, for instance Cortex-A9 does not support LPAE, if you have boards using such cores, then this would result in a kernel that would not boot on these platforms. Can that be a problem with the shmobile_defconfig?
Hi Florian, On Wed, Apr 25, 2018 at 8:17 PM, Florian Fainelli <f.fainelli@gmail.com> wrote: > On 04/25/2018 09:14 AM, Fabrizio Castro wrote: >> On iWave's iwg20m DDR1 512MB memory cannot be accessed with 32-bit >> addresses, hence we need LPAE. >> >> Signed-off-by: Biju Das <biju.das@bp.renesas.com> >> Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com> >> --- >> This information is mentioned in the "RZ/G Series User’s Manual: Hardware", >> Chapter 2, Area Map. Is this patch going to break the functionality of other >> boards? Comments welcome. > > LPAE is not supported by all Cortex-A class cores, for instance > Cortex-A9 does not support LPAE, if you have boards using such cores, Thanks for reminding me! > then this would result in a kernel that would not boot on these > platforms. Can that be a problem with the shmobile_defconfig? Yes it is... Gr{oetje,eeting}s, Geert
Hello Florian, Thank you for your feedback! > Subject: Re: [PATCH/RFC v2] ARM: shmobile: defconfig: Enable LPAE > > On 04/25/2018 09:14 AM, Fabrizio Castro wrote: > > On iWave's iwg20m DDR1 512MB memory cannot be accessed with 32-bit > > addresses, hence we need LPAE. > > > > Signed-off-by: Biju Das <biju.das@bp.renesas.com> > > Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com> > > --- > > This information is mentioned in the "RZ/G Series User’s Manual: Hardware", > > Chapter 2, Area Map. Is this patch going to break the functionality of other > > boards? Comments welcome. > > LPAE is not supported by all Cortex-A class cores, for instance > Cortex-A9 does not support LPAE, if you have boards using such cores, > then this would result in a kernel that would not boot on these > platforms. Can that be a problem with the shmobile_defconfig? It definitely is, therefore I am going to drop this patch as it would break things. Best regards, Fab > -- > Florian Renesas Electronics Europe Ltd, Dukes Meadow, Millboard Road, Bourne End, Buckinghamshire, SL8 5FH, UK. Registered in England & Wales under Registered No. 04586709.
diff --git a/arch/arm/configs/shmobile_defconfig b/arch/arm/configs/shmobile_defconfig index dd95d39..21b25e9 100644 --- a/arch/arm/configs/shmobile_defconfig +++ b/arch/arm/configs/shmobile_defconfig @@ -23,6 +23,7 @@ CONFIG_ARCH_R8A7792=y CONFIG_ARCH_R8A7793=y CONFIG_ARCH_R8A7794=y CONFIG_ARCH_SH73A0=y +CONFIG_ARM_LPAE=y CONFIG_PL310_ERRATA_588369=y CONFIG_ARM_ERRATA_754322=y CONFIG_PCI=y