| Message ID | 1444172150-29493-2-git-send-email-scottwood@freescale.com (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
On Tue, Oct 06, 2015 at 05:55:49PM -0500, Scott Wood wrote: > Commit a304e2d82a8c3 ("ppc64: purgatory: Reset primary cpu endian to > big-endian) changed bctr to rfid. rfid is book3s-only and will cause a > fatal exception on book3e. > > Purgatory is an isolated environment which makes importing information > about the subarch awkward, so instead rely on the fact that MSR_LE > should never be set on book3e, and the rfid is only needed if MSR_LE is > set (and thus needs to be cleared). In theory that MSR bit is reserved > on book3e, rather than zero, but in practice I have not seen it set. > > Signed-off-by: Scott Wood <scottwood@freescale.com> > Cc: Samuel Mendoza-Jonas <sam.mj@au1.ibm.com> > --- > v2: new patch Could I get a review of this from at lest one ppc person? > purgatory/arch/ppc64/v2wrap.S | 10 +++++++++- > 1 file changed, 9 insertions(+), 1 deletion(-) > > diff --git a/purgatory/arch/ppc64/v2wrap.S b/purgatory/arch/ppc64/v2wrap.S > index 179ade9..3534080 100644 > --- a/purgatory/arch/ppc64/v2wrap.S > +++ b/purgatory/arch/ppc64/v2wrap.S > @@ -116,9 +116,17 @@ master: > stw 7,0x5c(4) # and patch it into the kernel > mr 3,16 # restore dt address > > + mfmsr 5 > + andi. 10,5,1 # test MSR_LE > + bne little_endian > + > + li 5,0 # r5 will be 0 for kernel > + mtctr 4 # prepare branch to > + bctr # start kernel > + > +little_endian: # book3s-only > mtsrr0 4 # prepare branch to > > - mfmsr 5 > clrrdi 5,5,1 # clear MSR_LE > mtsrr1 5 > > -- > 2.1.4 > > > _______________________________________________ > kexec mailing list > kexec@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/kexec >
On Fri, 2015-10-16 at 10:48 +0900, Simon Horman wrote: > On Tue, Oct 06, 2015 at 05:55:49PM -0500, Scott Wood wrote: > > Commit a304e2d82a8c3 ("ppc64: purgatory: Reset primary cpu endian to > > big-endian) changed bctr to rfid. rfid is book3s-only and will cause a > > fatal exception on book3e. > > > > Purgatory is an isolated environment which makes importing information > > about the subarch awkward, so instead rely on the fact that MSR_LE > > should never be set on book3e, and the rfid is only needed if MSR_LE is > > set (and thus needs to be cleared). In theory that MSR bit is reserved > > on book3e, rather than zero, but in practice I have not seen it set. > > > > Signed-off-by: Scott Wood <scottwood@freescale.com> > > Cc: Samuel Mendoza-Jonas <sam.mj@au1.ibm.com> > > --- > > v2: new patch > > Could I get a review of this from at lest one ppc person? Michael, can you comment on this as well as patch 3/3? -Scott > > > purgatory/arch/ppc64/v2wrap.S | 10 +++++++++- > > 1 file changed, 9 insertions(+), 1 deletion(-) > > > > diff --git a/purgatory/arch/ppc64/v2wrap.S b/purgatory/arch/ppc64/v2wrap.S > > index 179ade9..3534080 100644 > > --- a/purgatory/arch/ppc64/v2wrap.S > > +++ b/purgatory/arch/ppc64/v2wrap.S > > @@ -116,9 +116,17 @@ master: > > stw 7,0x5c(4) # and patch it into the kernel > > mr 3,16 # restore dt address > > > > + mfmsr 5 > > + andi. 10,5,1 # test MSR_LE > > + bne little_endian > > + > > + li 5,0 # r5 will be 0 for kernel > > + mtctr 4 # prepare branch to > > + bctr # start kernel > > + > > +little_endian: # book3s-only > > mtsrr0 4 # prepare branch to > > > > - mfmsr 5 > > clrrdi 5,5,1 # clear MSR_LE > > mtsrr1 5 > >
On Tue, Oct 06, 2015 at 05:55:49PM -0500, Scott Wood wrote: > Commit a304e2d82a8c3 ("ppc64: purgatory: Reset primary cpu endian to > big-endian) changed bctr to rfid. rfid is book3s-only and will cause a > fatal exception on book3e. > > Purgatory is an isolated environment which makes importing information > about the subarch awkward, so instead rely on the fact that MSR_LE > should never be set on book3e, and the rfid is only needed if MSR_LE is > set (and thus needs to be cleared). In theory that MSR bit is reserved > on book3e, rather than zero, but in practice I have not seen it set. > > Signed-off-by: Scott Wood <scottwood@freescale.com> > Cc: Samuel Mendoza-Jonas <sam.mj@au1.ibm.com> > --- > v2: new patch Looks good to me, thanks for catching this! I'll ping Michael too if you'd like his reviewed-by. Reviewed-by: Samuel Mendoza-Jonas <sam.mj@au1.ibm.com> > > purgatory/arch/ppc64/v2wrap.S | 10 +++++++++- > 1 file changed, 9 insertions(+), 1 deletion(-) > > diff --git a/purgatory/arch/ppc64/v2wrap.S b/purgatory/arch/ppc64/v2wrap.S > index 179ade9..3534080 100644 > --- a/purgatory/arch/ppc64/v2wrap.S > +++ b/purgatory/arch/ppc64/v2wrap.S > @@ -116,9 +116,17 @@ master: > stw 7,0x5c(4) # and patch it into the kernel > mr 3,16 # restore dt address > > + mfmsr 5 > + andi. 10,5,1 # test MSR_LE > + bne little_endian > + > + li 5,0 # r5 will be 0 for kernel > + mtctr 4 # prepare branch to > + bctr # start kernel > + > +little_endian: # book3s-only > mtsrr0 4 # prepare branch to > > - mfmsr 5 > clrrdi 5,5,1 # clear MSR_LE > mtsrr1 5 > > -- > 2.1.4
On Mon, Nov 02, 2015 at 09:55:53AM +1100, Sam Mendoza-Jonas wrote: > On Tue, Oct 06, 2015 at 05:55:49PM -0500, Scott Wood wrote: > > Commit a304e2d82a8c3 ("ppc64: purgatory: Reset primary cpu endian to > > big-endian) changed bctr to rfid. rfid is book3s-only and will cause a > > fatal exception on book3e. > > > > Purgatory is an isolated environment which makes importing information > > about the subarch awkward, so instead rely on the fact that MSR_LE > > should never be set on book3e, and the rfid is only needed if MSR_LE is > > set (and thus needs to be cleared). In theory that MSR bit is reserved > > on book3e, rather than zero, but in practice I have not seen it set. > > > > Signed-off-by: Scott Wood <scottwood@freescale.com> > > Cc: Samuel Mendoza-Jonas <sam.mj@au1.ibm.com> > > --- > > v2: new patch > > Looks good to me, thanks for catching this! > I'll ping Michael too if you'd like his reviewed-by. > > Reviewed-by: Samuel Mendoza-Jonas <sam.mj@au1.ibm.com> Following up, also add my Tested-by: Samuel Mendoza-Jonas <sam.mj@au1.ibm.com> > > > > > purgatory/arch/ppc64/v2wrap.S | 10 +++++++++- > > 1 file changed, 9 insertions(+), 1 deletion(-) > > > > diff --git a/purgatory/arch/ppc64/v2wrap.S b/purgatory/arch/ppc64/v2wrap.S > > index 179ade9..3534080 100644 > > --- a/purgatory/arch/ppc64/v2wrap.S > > +++ b/purgatory/arch/ppc64/v2wrap.S > > @@ -116,9 +116,17 @@ master: > > stw 7,0x5c(4) # and patch it into the kernel > > mr 3,16 # restore dt address > > > > + mfmsr 5 > > + andi. 10,5,1 # test MSR_LE > > + bne little_endian > > + > > + li 5,0 # r5 will be 0 for kernel > > + mtctr 4 # prepare branch to > > + bctr # start kernel > > + > > +little_endian: # book3s-only > > mtsrr0 4 # prepare branch to > > > > - mfmsr 5 > > clrrdi 5,5,1 # clear MSR_LE > > mtsrr1 5 > > > > -- > > 2.1.4 > > _______________________________________________ > Linuxppc-dev mailing list > Linuxppc-dev@lists.ozlabs.org > https://lists.ozlabs.org/listinfo/linuxppc-dev
On Mon, Nov 02, 2015 at 11:21:43AM +1100, Sam Mendoza-Jonas wrote: > On Mon, Nov 02, 2015 at 09:55:53AM +1100, Sam Mendoza-Jonas wrote: > > On Tue, Oct 06, 2015 at 05:55:49PM -0500, Scott Wood wrote: > > > Commit a304e2d82a8c3 ("ppc64: purgatory: Reset primary cpu endian to > > > big-endian) changed bctr to rfid. rfid is book3s-only and will cause a > > > fatal exception on book3e. > > > > > > Purgatory is an isolated environment which makes importing information > > > about the subarch awkward, so instead rely on the fact that MSR_LE > > > should never be set on book3e, and the rfid is only needed if MSR_LE is > > > set (and thus needs to be cleared). In theory that MSR bit is reserved > > > on book3e, rather than zero, but in practice I have not seen it set. > > > > > > Signed-off-by: Scott Wood <scottwood@freescale.com> > > > Cc: Samuel Mendoza-Jonas <sam.mj@au1.ibm.com> > > > --- > > > v2: new patch > > > > Looks good to me, thanks for catching this! > > I'll ping Michael too if you'd like his reviewed-by. > > > > Reviewed-by: Samuel Mendoza-Jonas <sam.mj@au1.ibm.com> > > Following up, also add my > > Tested-by: Samuel Mendoza-Jonas <sam.mj@au1.ibm.com> Thanks, I have queued this up for v2.0.11.
diff --git a/purgatory/arch/ppc64/v2wrap.S b/purgatory/arch/ppc64/v2wrap.S index 179ade9..3534080 100644 --- a/purgatory/arch/ppc64/v2wrap.S +++ b/purgatory/arch/ppc64/v2wrap.S @@ -116,9 +116,17 @@ master: stw 7,0x5c(4) # and patch it into the kernel mr 3,16 # restore dt address + mfmsr 5 + andi. 10,5,1 # test MSR_LE + bne little_endian + + li 5,0 # r5 will be 0 for kernel + mtctr 4 # prepare branch to + bctr # start kernel + +little_endian: # book3s-only mtsrr0 4 # prepare branch to - mfmsr 5 clrrdi 5,5,1 # clear MSR_LE mtsrr1 5
Commit a304e2d82a8c3 ("ppc64: purgatory: Reset primary cpu endian to big-endian) changed bctr to rfid. rfid is book3s-only and will cause a fatal exception on book3e. Purgatory is an isolated environment which makes importing information about the subarch awkward, so instead rely on the fact that MSR_LE should never be set on book3e, and the rfid is only needed if MSR_LE is set (and thus needs to be cleared). In theory that MSR bit is reserved on book3e, rather than zero, but in practice I have not seen it set. Signed-off-by: Scott Wood <scottwood@freescale.com> Cc: Samuel Mendoza-Jonas <sam.mj@au1.ibm.com> --- v2: new patch purgatory/arch/ppc64/v2wrap.S | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)