Hi Yi,
On 03/14/2018 05:34 AM, Li Yi (Adam) wrote:
So set it in the DT CPU features code also.
This results in eg:
$ LD_SHOW_AUXV=1 /bin/true | grep "AT_.*PLATFORM"
AT_PLATFORM: power9
AT_BASE_PLATFORM:power9
Is this issue related with DD2.2 CPU?
I tested on a Boston system with DD2.1 CPU, with kernel 4.14.23,
AT_BASE_PLATFORM value is correct:
[root@boston-sh-04 ~]# LD_SHOW_AUXV=1 /bin/true | grep "AT_.*PLATFORM"
AT_PLATFORM: power9
AT_BASE_PLATFORM:power9
[root@boston-sh-04 ~]# uname -a
Linux boston-sh-04 4.14.23 #1 SMP Sat Mar 3 12:14:56 CST 2018 ppc64le
ppc64le ppc64le GNU/Linux
It's not related to the processor version, rather it's related to if you
are under a VM or running on baremetal. The issue happens on baremetal
when you are using DT to get the CPU features. So I guess the test you
performed above is on a VM? On DD2.1 baremetal AT_BASE_PLATFORM is
missing as on a DD2.2 baremetal (if mpe's patch is not applied):
root@r222l:~# LD_SHOW_AUXV=1 /bin/true | grep "AT_.*PLATFORM"
AT_PLATFORM: power9
root@r222l:~# lscpu | fgrep Model
Model: 2.1 (pvr 004e 1201)
Model name: POWER9, altivec supported
root@r222l:~# uname -a
Linux r222l 4.13.0-32-generic #35-Ubuntu SMP Thu Jan 25 09:05:20 UTC 2018
ppc64le ppc64le ppc64le GNU/Linux
Regards,
Gustavo
Thanks,
-Yi
Signed-off-by: Michael Ellerman <m...@ellerman.id.au>
---
arch/powerpc/kernel/dt_cpu_ftrs.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/arch/powerpc/kernel/dt_cpu_ftrs.c
b/arch/powerpc/kernel/dt_cpu_ftrs.c
index 945e2c29ad2d..0bcfb0f256e1 100644
--- a/arch/powerpc/kernel/dt_cpu_ftrs.c
+++ b/arch/powerpc/kernel/dt_cpu_ftrs.c
@@ -720,6 +720,9 @@ static void __init cpufeatures_setup_finished(void)
cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
}
+ /* Make sure powerpc_base_platform is non-NULL */
+ powerpc_base_platform = cur_cpu_spec->platform;
+
system_registers.lpcr = mfspr(SPRN_LPCR);
system_registers.hfscr = mfspr(SPRN_HFSCR);
system_registers.fscr = mfspr(SPRN_FSCR);
--
2.14.1
