| Message ID | 1484827674-31341-1-git-send-email-yamada.masahiro@socionext.com |
|---|---|
| State | Superseded |
| Headers | show |
On Thu, Jan 19, 2017 at 2:07 PM, Masahiro Yamada <yamada.masahiro@socionext.com> wrote: > This feature seems to be sometimes misunderstood. The intention is > > [1] Bring the slaves into U-Boot proper image, not SPL (unless > you have a special reason). > > [2] The operation must be done in a board (SoC) specific manner > since how to wake the slaves from the Boot ROM is SoC specific. > > [3] The slaves must enter U-Boot proper after U-Boot relocates > itself because the "cpu-release-addr" property points to the > relocated memory area. > > [2] is already explained in the help. We can make [1] even clearer > by mentioning "U-Boot proper" instead of "U-Boot". [3] is missing, > so I am adding it to the list. > > Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> > --- > > arch/arm/cpu/armv8/Kconfig | 7 +++++-- > 1 file changed, 5 insertions(+), 2 deletions(-) > > diff --git a/arch/arm/cpu/armv8/Kconfig b/arch/arm/cpu/armv8/Kconfig > index 22dce88..7388eca 100644 > --- a/arch/arm/cpu/armv8/Kconfig > +++ b/arch/arm/cpu/armv8/Kconfig > @@ -12,8 +12,11 @@ config ARMV8_SPIN_TABLE > To use this feature, you must do: > - Specify enable-method = "spin-table" in each CPU node in the > Device Tree you are using to boot the kernel > - - Let secondary CPUs in U-Boot (in a board specific manner) > - before the master CPU jumps to the kernel > + - Bring secondary CPUs into U-Boot proper (in a board specific > + manner) before the master CPU jumps to the kernel, but *after* > + relocation. Otherwise, the master CPU will see a different copy > + of the spin code, then the secondary CPUs will spin in the > + unprotected memory area. > > U-Boot automatically does: > - Set "cpu-release-addr" property of each CPU node > -- > 2.7.4 > > _______________________________________________ > U-Boot mailing list > U-Boot@lists.denx.de > http://lists.denx.de/mailman/listinfo/u-boot This patch is: Reviewed-by: Oded Gabbay <oded.gabbay@gmail.com> _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
diff --git a/arch/arm/cpu/armv8/Kconfig b/arch/arm/cpu/armv8/Kconfig index 22dce88..7388eca 100644 --- a/arch/arm/cpu/armv8/Kconfig +++ b/arch/arm/cpu/armv8/Kconfig @@ -12,8 +12,11 @@ config ARMV8_SPIN_TABLE To use this feature, you must do: - Specify enable-method = "spin-table" in each CPU node in the Device Tree you are using to boot the kernel - - Let secondary CPUs in U-Boot (in a board specific manner) - before the master CPU jumps to the kernel + - Bring secondary CPUs into U-Boot proper (in a board specific + manner) before the master CPU jumps to the kernel, but *after* + relocation. Otherwise, the master CPU will see a different copy + of the spin code, then the secondary CPUs will spin in the + unprotected memory area. U-Boot automatically does: - Set "cpu-release-addr" property of each CPU node
This feature seems to be sometimes misunderstood. The intention is [1] Bring the slaves into U-Boot proper image, not SPL (unless you have a special reason). [2] The operation must be done in a board (SoC) specific manner since how to wake the slaves from the Boot ROM is SoC specific. [3] The slaves must enter U-Boot proper after U-Boot relocates itself because the "cpu-release-addr" property points to the relocated memory area. [2] is already explained in the help. We can make [1] even clearer by mentioning "U-Boot proper" instead of "U-Boot". [3] is missing, so I am adding it to the list. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> --- arch/arm/cpu/armv8/Kconfig | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) -- 2.7.4 _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot