On Fri, Dec 6, 2019 at 2:50 PM Rick Chen <rickche...@gmail.com> wrote: > > > From: Lukas Auer [mailto:lukas.a...@aisec.fraunhofer.de] > > Sent: Wednesday, December 04, 2019 5:40 AM > > To: u-boot@lists.denx.de > > Cc: Rick Jian-Zhi Chen(陳建志); Anup Patel; Bin Meng; Lukas Auer; Anup Patel > > Subject: [PATCH 1/4] spl: opensbi: specify main hart as preferred boot hart > > > > OpenSBI uses a relocation lottery to determine the hart to relocate OpenSBI > > to its link address. In the U-Boot SPL boot flow, the main hart schedules > > the secondary harts to enter OpenSBI before doing so itself. > > One of the secondary harts will therefore always be the winner of the > > relocation lottery. This is problematic if the link address ranges of > > OpenSBI and U-Boot SPL overlap. OpenSBI will be relocated and therefore > > overwrite U-Boot SPL while some harts may still run it, leading to code > > corruption. > > > > Avoid this problem by specifying the main hart as the preferred boot hart > > to perform the OpenSBI relocation. The main hart will be the last hart to > > enter OpenSBI, relocation can therefore occur safely. > > > > The boot hart field was added to version 2 of the OpenSBI FW_DYNAMIC info > > structure. The header file include/opensbi.h is synchronized with > > include/sbi/fw_dynamic.h from the OpenSBI project to update the info > > structure. The header file is recent as of commit > > 7a13beb21326 ("firmware: Add preferred boot HART field in struct > > fw_dynamic_info"). > > > > Reported-by: Rick Chen <r...@andestech.com> > > Suggested-by: Anup Patel <anup.pa...@wdc.com> > > Signed-off-by: Lukas Auer <lukas.a...@aisec.fraunhofer.de> > > --- > > > > Reviewed-by: Rick Chen <r...@andestech.com> > Tested-by: Rick Chen <r...@andestech.com> > > > common/spl/spl_opensbi.c | 1 + > > include/opensbi.h | 18 +++++++++++++++++- > > 2 files changed, 18 insertions(+), 1 deletion(-) > > > > diff --git a/common/spl/spl_opensbi.c b/common/spl/spl_opensbi.c index > > a6b4480ed2..79ee7edcf9 100644 > > --- a/common/spl/spl_opensbi.c > > +++ b/common/spl/spl_opensbi.c > > @@ -69,6 +69,7 @@ void spl_invoke_opensbi(struct spl_image_info *spl_image) > > opensbi_info.next_addr = uboot_entry; > > opensbi_info.next_mode = FW_DYNAMIC_INFO_NEXT_MODE_S; > > opensbi_info.options = SBI_SCRATCH_NO_BOOT_PRINTS; > > + opensbi_info.boot_hart = gd->arch.boot_hart; > > > > opensbi_entry = (void (*)(ulong, ulong, > > ulong))spl_image->entry_point; > > invalidate_icache_all(); > > diff --git a/include/opensbi.h b/include/opensbi.h index > > 9f1d62e7dd..d812cc8ccd 100644 > > --- a/include/opensbi.h > > +++ b/include/opensbi.h > > @@ -11,7 +11,7 @@ > > #define FW_DYNAMIC_INFO_MAGIC_VALUE 0x4942534f > > > > /** Maximum supported info version */ > > -#define FW_DYNAMIC_INFO_VERSION 0x1 > > +#define FW_DYNAMIC_INFO_VERSION 0x2 > > > > /** Possible next mode values */ > > #define FW_DYNAMIC_INFO_NEXT_MODE_U 0x0 > > @@ -35,6 +35,22 @@ struct fw_dynamic_info { > > unsigned long next_mode; > > /** Options for OpenSBI library */ > > unsigned long options; > > + /** > > + * Preferred boot HART id > > + * > > + * It is possible that the previous booting stage uses same link > > + * address as the FW_DYNAMIC firmware. In this case, the relocation > > + * lottery mechanism can potentially overwrite the previous booting > > + * stage while other HARTs are still running in the previous booting > > + * stage leading to boot-time crash. To avoid this boot-time crash, > > + * the previous booting stage can specify last HART that will jump > > + * to the FW_DYNAMIC firmware as the preferred boot HART. > > + * > > + * To avoid specifying a preferred boot HART, the previous booting > > + * stage can set it to -1UL which will force the FW_DYNAMIC firmware > > + * to use the relocation lottery mechanism. > > + */ > > + unsigned long boot_hart; > > } __packed; > > > > #endif > > -- > > 2.21.0 > >
Looks good to me. Reviewed-by: Anup Patel <anup.pa...@wdc.com> Regards, Anup
