| Message ID | 1480423205-48436-9-git-send-email-vladimir.murzin@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, Nov 29, 2016 at 12:39:50PM +0000, Vladimir Murzin wrote: > Mediatek's and Qualcomm's platform code has reference to > secondary_startup_arm and that breaks NOMMU build. This needs to explain why this is safe in the presence of EFM32. > Cc: Russell King <linux@armlinux.org.uk> > Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> > --- > arch/arm/kernel/head-nommu.S | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/arch/arm/kernel/head-nommu.S b/arch/arm/kernel/head-nommu.S > index 7317554..2ab026f 100644 > --- a/arch/arm/kernel/head-nommu.S > +++ b/arch/arm/kernel/head-nommu.S > @@ -89,6 +89,12 @@ ENDPROC(stext) > > #ifdef CONFIG_SMP > .text > + .arm > +ENTRY(secondary_startup_arm) > + THUMB( badr r9, 1f ) @ Kernel is entered in ARM. > + THUMB( bx r9 ) @ If this is a Thumb-2 kernel, > + THUMB( .thumb ) @ switch to Thumb now. > + THUMB(1: ) > ENTRY(secondary_startup) > /* > * Common entry point for secondary CPUs. > @@ -126,6 +132,7 @@ ENTRY(secondary_startup) > mov fp, #0 > b secondary_start_kernel > ENDPROC(secondary_startup) > +ENDPROC(secondary_startup_arm) > > .type __secondary_data, %object > __secondary_data: > -- > 1.7.9.5 >
On 29/11/16 17:14, Russell King - ARM Linux wrote: > On Tue, Nov 29, 2016 at 12:39:50PM +0000, Vladimir Murzin wrote: >> Mediatek's and Qualcomm's platform code has reference to >> secondary_startup_arm and that breaks NOMMU build. > > This needs to explain why this is safe in the presence of EFM32. > It did not explode by pure luck M-class doesn't support SMP. The code needs to include case for CONFIG_CPU_THUMBONLY. I'll include update in the next version. Thanks Vladimir >> Cc: Russell King <linux@armlinux.org.uk> >> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> >> --- >> arch/arm/kernel/head-nommu.S | 7 +++++++ >> 1 file changed, 7 insertions(+) >> >> diff --git a/arch/arm/kernel/head-nommu.S b/arch/arm/kernel/head-nommu.S >> index 7317554..2ab026f 100644 >> --- a/arch/arm/kernel/head-nommu.S >> +++ b/arch/arm/kernel/head-nommu.S >> @@ -89,6 +89,12 @@ ENDPROC(stext) >> >> #ifdef CONFIG_SMP >> .text >> + .arm >> +ENTRY(secondary_startup_arm) >> + THUMB( badr r9, 1f ) @ Kernel is entered in ARM. >> + THUMB( bx r9 ) @ If this is a Thumb-2 kernel, >> + THUMB( .thumb ) @ switch to Thumb now. >> + THUMB(1: ) >> ENTRY(secondary_startup) >> /* >> * Common entry point for secondary CPUs. >> @@ -126,6 +132,7 @@ ENTRY(secondary_startup) >> mov fp, #0 >> b secondary_start_kernel >> ENDPROC(secondary_startup) >> +ENDPROC(secondary_startup_arm) >> >> .type __secondary_data, %object >> __secondary_data: >> -- >> 1.7.9.5 >> >
diff --git a/arch/arm/kernel/head-nommu.S b/arch/arm/kernel/head-nommu.S index 7317554..2ab026f 100644 --- a/arch/arm/kernel/head-nommu.S +++ b/arch/arm/kernel/head-nommu.S @@ -89,6 +89,12 @@ ENDPROC(stext) #ifdef CONFIG_SMP .text + .arm +ENTRY(secondary_startup_arm) + THUMB( badr r9, 1f ) @ Kernel is entered in ARM. + THUMB( bx r9 ) @ If this is a Thumb-2 kernel, + THUMB( .thumb ) @ switch to Thumb now. + THUMB(1: ) ENTRY(secondary_startup) /* * Common entry point for secondary CPUs. @@ -126,6 +132,7 @@ ENTRY(secondary_startup) mov fp, #0 b secondary_start_kernel ENDPROC(secondary_startup) +ENDPROC(secondary_startup_arm) .type __secondary_data, %object __secondary_data:
Mediatek's and Qualcomm's platform code has reference to secondary_startup_arm and that breaks NOMMU build. Cc: Russell King <linux@armlinux.org.uk> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> --- arch/arm/kernel/head-nommu.S | 7 +++++++ 1 file changed, 7 insertions(+)