| Message ID | 20240606133628.3330423-8-luca.fancellu@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Add Armv8-R AArch64 support | expand |
On Thu, 6 Jun 2024 14:36:28 +0100 Luca Fancellu <luca.fancellu@arm.com> wrote: Hi, > When bootwrapper is compiled with Xen support and it is started > at EL2 on Armv8-R AArch64, keep the current EL and jump to the > Xen image. > > Additionally, don't permit the usage of hvc conduit when Xen > kernel is passed, because it's not supported. Mmh, but this is unrelated to v8R, isn't it? And I am not sure there is too much merit in checking this here? After all PSCI *could* be triggered like this from EL2 (to EL2) in the future, even if the *current* Xen implementation does not support this. > Signed-off-by: Luca Fancellu <luca.fancellu@arm.com> > --- > Makefile.am | 1 + > arch/aarch64/boot.S | 7 +++++++ > configure.ac | 3 +++ > 3 files changed, 11 insertions(+) > > diff --git a/Makefile.am b/Makefile.am > index 34fbfb1f4ff8..bafce34682c3 100644 > --- a/Makefile.am > +++ b/Makefile.am > @@ -112,6 +112,7 @@ XEN_CHOSEN := xen,xen-bootargs = \"$(XEN_CMDLINE)\"; \ > compatible = \"xen,linux-zimage\", \"xen,multiboot-module\"; \ > reg = <0x0 $(DOM0_OFFSET) 0x0 $(KERNEL_SIZE)>; \ > }; > +DEFINES += -DXEN > endif > > if INITRD > diff --git a/arch/aarch64/boot.S b/arch/aarch64/boot.S > index b2b9863b8d6a..0b30b82ad6d9 100644 > --- a/arch/aarch64/boot.S > +++ b/arch/aarch64/boot.S > @@ -88,6 +88,7 @@ reset_at_el2: > cmp x0, 0xf > bne reset_no_el3 > > +#if !defined(XEN) > /* > * Armv8-R AArch64 is found, check if Linux can be booted. Does Xen equally rely on VMSA in EL1? Or does it not care, and just leaves the EL1 setup totally to the guest? Supporting PMSA guests as well? Just asking to check whether the !XEN part would be in the right place then. > * Check MSA_frac, bits [55:52]: > @@ -107,6 +108,12 @@ reset_at_el2: > mov w0, #SPSR_KERNEL_EL1 > ldr x1, =spsr_to_elx > str w0, [x1] > +#else > + /* Start XEN on Armv8-R at EL2 */ > + mov w0, #1 > + ldr x1, =flag_keep_el > + str w0, [x1] > +#endif > > cpuid x0, x1 > bl find_logical_id > diff --git a/configure.ac b/configure.ac > index 44459a4c849e..a5175db4148a 100644 > --- a/configure.ac > +++ b/configure.ac > @@ -95,6 +95,9 @@ AM_CONDITIONAL([PSCI_HVC], [test "x$USE_PSCI" = "xhvc"]) > AS_IF([test "x$USE_PSCI" = "xno" -a "x$KERNEL_ES" = "x32"], > [AC_MSG_ERROR([With an AArch32 kernel, boot method must be PSCI.])] > ) > +AS_IF([test "x$USE_PSCI" = "xhvc" -a "x$X_IMAGE" != "x"], > + [AC_MSG_ERROR([With Xen kernel, PSCI conduit must be smc.])] > +) As mentioned above, I am not sure this is too helpful. Cheers, Andre > AC_SUBST([PSCI_METHOD], [$USE_PSCI]) > > # Allow a user to pass --with-initrd
Hi Andre, > On 21 Jun 2024, at 11:36, Andre Przywara <Andre.Przywara@arm.com> wrote: > > On Thu, 6 Jun 2024 14:36:28 +0100 > Luca Fancellu <luca.fancellu@arm.com> wrote: > > Hi, > >> When bootwrapper is compiled with Xen support and it is started >> at EL2 on Armv8-R AArch64, keep the current EL and jump to the >> Xen image. >> >> Additionally, don't permit the usage of hvc conduit when Xen >> kernel is passed, because it's not supported. > > Mmh, but this is unrelated to v8R, isn't it? > And I am not sure there is too much merit in checking this here? > After all PSCI *could* be triggered like this from EL2 (to EL2) in the > future, even if the *current* Xen implementation does not support this. Yes, it’s only the current Xen implementation that doesn’t support this. > >> Signed-off-by: Luca Fancellu <luca.fancellu@arm.com> >> --- >> Makefile.am | 1 + >> arch/aarch64/boot.S | 7 +++++++ >> configure.ac | 3 +++ >> 3 files changed, 11 insertions(+) >> >> diff --git a/Makefile.am b/Makefile.am >> index 34fbfb1f4ff8..bafce34682c3 100644 >> --- a/Makefile.am >> +++ b/Makefile.am >> @@ -112,6 +112,7 @@ XEN_CHOSEN := xen,xen-bootargs = \"$(XEN_CMDLINE)\"; \ >> compatible = \"xen,linux-zimage\", \"xen,multiboot-module\"; \ >> reg = <0x0 $(DOM0_OFFSET) 0x0 $(KERNEL_SIZE)>; \ >> }; >> +DEFINES += -DXEN >> endif >> >> if INITRD >> diff --git a/arch/aarch64/boot.S b/arch/aarch64/boot.S >> index b2b9863b8d6a..0b30b82ad6d9 100644 >> --- a/arch/aarch64/boot.S >> +++ b/arch/aarch64/boot.S >> @@ -88,6 +88,7 @@ reset_at_el2: >> cmp x0, 0xf >> bne reset_no_el3 >> >> +#if !defined(XEN) >> /* >> * Armv8-R AArch64 is found, check if Linux can be booted. > > Does Xen equally rely on VMSA in EL1? Or does it not care, and just > leaves the EL1 setup totally to the guest? Supporting PMSA guests > as well? > Just asking to check whether the !XEN part would be in the right place > then. Xen does not care and it just leaves the EL1 setup to the guest. > >> * Check MSA_frac, bits [55:52]: >> @@ -107,6 +108,12 @@ reset_at_el2: >> mov w0, #SPSR_KERNEL_EL1 >> ldr x1, =spsr_to_elx >> str w0, [x1] >> +#else >> + /* Start XEN on Armv8-R at EL2 */ >> + mov w0, #1 >> + ldr x1, =flag_keep_el >> + str w0, [x1] >> +#endif >> >> cpuid x0, x1 >> bl find_logical_id >> diff --git a/configure.ac b/configure.ac >> index 44459a4c849e..a5175db4148a 100644 >> --- a/configure.ac >> +++ b/configure.ac >> @@ -95,6 +95,9 @@ AM_CONDITIONAL([PSCI_HVC], [test "x$USE_PSCI" = "xhvc"]) >> AS_IF([test "x$USE_PSCI" = "xno" -a "x$KERNEL_ES" = "x32"], >> [AC_MSG_ERROR([With an AArch32 kernel, boot method must be PSCI.])] >> ) >> +AS_IF([test "x$USE_PSCI" = "xhvc" -a "x$X_IMAGE" != "x"], >> + [AC_MSG_ERROR([With Xen kernel, PSCI conduit must be smc.])] >> +) > > As mentioned above, I am not sure this is too helpful. Ok, so your proposal is to remove this check, am I right? Cheers, Luca
Hi Andre, > >> >>> * Check MSA_frac, bits [55:52]: >>> @@ -107,6 +108,12 @@ reset_at_el2: >>> mov w0, #SPSR_KERNEL_EL1 >>> ldr x1, =spsr_to_elx >>> str w0, [x1] >>> +#else >>> + /* Start XEN on Armv8-R at EL2 */ >>> + mov w0, #1 >>> + ldr x1, =flag_keep_el >>> + str w0, [x1] >>> +#endif >>> >>> cpuid x0, x1 >>> bl find_logical_id >>> diff --git a/configure.ac b/configure.ac >>> index 44459a4c849e..a5175db4148a 100644 >>> --- a/configure.ac >>> +++ b/configure.ac >>> @@ -95,6 +95,9 @@ AM_CONDITIONAL([PSCI_HVC], [test "x$USE_PSCI" = "xhvc"]) >>> AS_IF([test "x$USE_PSCI" = "xno" -a "x$KERNEL_ES" = "x32"], >>> [AC_MSG_ERROR([With an AArch32 kernel, boot method must be PSCI.])] >>> ) >>> +AS_IF([test "x$USE_PSCI" = "xhvc" -a "x$X_IMAGE" != "x"], >>> + [AC_MSG_ERROR([With Xen kernel, PSCI conduit must be smc.])] >>> +) >> >> As mentioned above, I am not sure this is too helpful. > > Ok, so your proposal is to remove this check, am I right? Gentle ping on this. Cheers, Luca
On Mon, 24 Jun 2024 14:28:24 +0100 Luca Fancellu <Luca.Fancellu@arm.com> wrote: > Hi Andre, > > > On 21 Jun 2024, at 11:36, Andre Przywara <Andre.Przywara@arm.com> wrote: > > > > On Thu, 6 Jun 2024 14:36:28 +0100 > > Luca Fancellu <luca.fancellu@arm.com> wrote: > > > > Hi, > > > >> When bootwrapper is compiled with Xen support and it is started > >> at EL2 on Armv8-R AArch64, keep the current EL and jump to the > >> Xen image. > >> > >> Additionally, don't permit the usage of hvc conduit when Xen > >> kernel is passed, because it's not supported. > > > > Mmh, but this is unrelated to v8R, isn't it? > > And I am not sure there is too much merit in checking this here? > > After all PSCI *could* be triggered like this from EL2 (to EL2) in the > > future, even if the *current* Xen implementation does not support this. > > Yes, it’s only the current Xen implementation that doesn’t support this. > > > > >> Signed-off-by: Luca Fancellu <luca.fancellu@arm.com> > >> --- > >> Makefile.am | 1 + > >> arch/aarch64/boot.S | 7 +++++++ > >> configure.ac | 3 +++ > >> 3 files changed, 11 insertions(+) > >> > >> diff --git a/Makefile.am b/Makefile.am > >> index 34fbfb1f4ff8..bafce34682c3 100644 > >> --- a/Makefile.am > >> +++ b/Makefile.am > >> @@ -112,6 +112,7 @@ XEN_CHOSEN := xen,xen-bootargs = \"$(XEN_CMDLINE)\"; \ > >> compatible = \"xen,linux-zimage\", \"xen,multiboot-module\"; \ > >> reg = <0x0 $(DOM0_OFFSET) 0x0 $(KERNEL_SIZE)>; \ > >> }; > >> +DEFINES += -DXEN > >> endif > >> > >> if INITRD > >> diff --git a/arch/aarch64/boot.S b/arch/aarch64/boot.S > >> index b2b9863b8d6a..0b30b82ad6d9 100644 > >> --- a/arch/aarch64/boot.S > >> +++ b/arch/aarch64/boot.S > >> @@ -88,6 +88,7 @@ reset_at_el2: > >> cmp x0, 0xf > >> bne reset_no_el3 > >> > >> +#if !defined(XEN) > >> /* > >> * Armv8-R AArch64 is found, check if Linux can be booted. > > > > Does Xen equally rely on VMSA in EL1? Or does it not care, and just > > leaves the EL1 setup totally to the guest? Supporting PMSA guests > > as well? > > Just asking to check whether the !XEN part would be in the right place > > then. > > Xen does not care and it just leaves the EL1 setup to the guest. > > > > >> * Check MSA_frac, bits [55:52]: > >> @@ -107,6 +108,12 @@ reset_at_el2: > >> mov w0, #SPSR_KERNEL_EL1 > >> ldr x1, =spsr_to_elx > >> str w0, [x1] > >> +#else > >> + /* Start XEN on Armv8-R at EL2 */ > >> + mov w0, #1 > >> + ldr x1, =flag_keep_el > >> + str w0, [x1] > >> +#endif > >> > >> cpuid x0, x1 > >> bl find_logical_id > >> diff --git a/configure.ac b/configure.ac > >> index 44459a4c849e..a5175db4148a 100644 > >> --- a/configure.ac > >> +++ b/configure.ac > >> @@ -95,6 +95,9 @@ AM_CONDITIONAL([PSCI_HVC], [test "x$USE_PSCI" = "xhvc"]) > >> AS_IF([test "x$USE_PSCI" = "xno" -a "x$KERNEL_ES" = "x32"], > >> [AC_MSG_ERROR([With an AArch32 kernel, boot method must be PSCI.])] > >> ) > >> +AS_IF([test "x$USE_PSCI" = "xhvc" -a "x$X_IMAGE" != "x"], > >> + [AC_MSG_ERROR([With Xen kernel, PSCI conduit must be smc.])] > >> +) > > > > As mentioned above, I am not sure this is too helpful. > > Ok, so your proposal is to remove this check, am I right? Yes, I think this is overzealous. Cheers, Andre
diff --git a/Makefile.am b/Makefile.am index 34fbfb1f4ff8..bafce34682c3 100644 --- a/Makefile.am +++ b/Makefile.am @@ -112,6 +112,7 @@ XEN_CHOSEN := xen,xen-bootargs = \"$(XEN_CMDLINE)\"; \ compatible = \"xen,linux-zimage\", \"xen,multiboot-module\"; \ reg = <0x0 $(DOM0_OFFSET) 0x0 $(KERNEL_SIZE)>; \ }; +DEFINES += -DXEN endif if INITRD diff --git a/arch/aarch64/boot.S b/arch/aarch64/boot.S index b2b9863b8d6a..0b30b82ad6d9 100644 --- a/arch/aarch64/boot.S +++ b/arch/aarch64/boot.S @@ -88,6 +88,7 @@ reset_at_el2: cmp x0, 0xf bne reset_no_el3 +#if !defined(XEN) /* * Armv8-R AArch64 is found, check if Linux can be booted. * Check MSA_frac, bits [55:52]: @@ -107,6 +108,12 @@ reset_at_el2: mov w0, #SPSR_KERNEL_EL1 ldr x1, =spsr_to_elx str w0, [x1] +#else + /* Start XEN on Armv8-R at EL2 */ + mov w0, #1 + ldr x1, =flag_keep_el + str w0, [x1] +#endif cpuid x0, x1 bl find_logical_id diff --git a/configure.ac b/configure.ac index 44459a4c849e..a5175db4148a 100644 --- a/configure.ac +++ b/configure.ac @@ -95,6 +95,9 @@ AM_CONDITIONAL([PSCI_HVC], [test "x$USE_PSCI" = "xhvc"]) AS_IF([test "x$USE_PSCI" = "xno" -a "x$KERNEL_ES" = "x32"], [AC_MSG_ERROR([With an AArch32 kernel, boot method must be PSCI.])] ) +AS_IF([test "x$USE_PSCI" = "xhvc" -a "x$X_IMAGE" != "x"], + [AC_MSG_ERROR([With Xen kernel, PSCI conduit must be smc.])] +) AC_SUBST([PSCI_METHOD], [$USE_PSCI]) # Allow a user to pass --with-initrd
When bootwrapper is compiled with Xen support and it is started at EL2 on Armv8-R AArch64, keep the current EL and jump to the Xen image. Additionally, don't permit the usage of hvc conduit when Xen kernel is passed, because it's not supported. Signed-off-by: Luca Fancellu <luca.fancellu@arm.com> --- Makefile.am | 1 + arch/aarch64/boot.S | 7 +++++++ configure.ac | 3 +++ 3 files changed, 11 insertions(+)