korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-12-13 05:54:23 +08:00
Code Issues Packages Projects Releases Wiki Activity

powerpc/powernv: POWER9 support for msgsnd/doorbell IPI

Browse Source 
POWER9 requires msgsync for receiver-side synchronization, and a DD1
workaround restricts IPIs to core-local.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Drop no longer needed asm feature macro changes]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Nicholas Piggin 2017-04-13 20:16:24 +10:00 committed by Michael Ellerman
parent a5adf28246
commit 6b3edefefa
3 changed files with 31 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
arch/powerpc/include/asm/dbell.h
View File

@ -51,6 +51,9 @@ static inline void ppc_msgsnd_sync(void)
/* sync after taking message interrupt */
static inline void ppc_msgsync(void)
{
/* sync is not required when taking messages from the same core */
__asm__ __volatile__ (ASM_FTR_IFSET(PPC_MSGSYNC " ; lwsync", "", %0)
: : "i" (CPU_FTR_HVMODE|CPU_FTR_ARCH_300));
}
#else /* CONFIG_PPC_BOOK3S */

2
arch/powerpc/include/asm/ppc-opcode.h
View File

@ -161,6 +161,7 @@
#define PPC_INST_MFTMR 0x7c0002dc
#define PPC_INST_MSGSND 0x7c00019c
#define PPC_INST_MSGCLR 0x7c0001dc
#define PPC_INST_MSGSYNC 0x7c0006ec
#define PPC_INST_MSGSNDP 0x7c00011c
#define PPC_INST_MTTMR 0x7c0003dc
#define PPC_INST_NOP 0x60000000
@ -345,6 +346,7 @@
___PPC_RB(b) | __PPC_EH(eh))
#define PPC_MSGSND(b) stringify_in_c(.long PPC_INST_MSGSND | \
___PPC_RB(b))
#define PPC_MSGSYNC stringify_in_c(.long PPC_INST_MSGSYNC)
#define PPC_MSGCLR(b) stringify_in_c(.long PPC_INST_MSGCLR | \
___PPC_RB(b))
#define PPC_MSGSNDP(b) stringify_in_c(.long PPC_INST_MSGSNDP | \

28
arch/powerpc/platforms/powernv/smp.c
View File

@ -257,6 +257,23 @@ static void pnv_cause_ipi(int cpu)
icp_ops->cause_ipi(cpu);
}
static void pnv_p9_dd1_cause_ipi(int cpu)
{
int this_cpu = get_cpu();
/*
* POWER9 DD1 has a global addressed msgsnd, but for now we restrict
* IPIs to same core, because it requires additional synchronization
* for inter-core doorbells which we do not implement.
*/
if (cpumask_test_cpu(cpu, cpu_sibling_mask(this_cpu)))
doorbell_global_ipi(cpu);
else
icp_ops->cause_ipi(cpu);
put_cpu();
}
static void __init pnv_smp_probe(void)
{
if (xive_enabled())
@ -264,8 +281,15 @@ static void __init pnv_smp_probe(void)
else
xics_smp_probe();
if (cpu_has_feature(CPU_FTR_DBELL) && !cpu_has_feature(CPU_FTR_ARCH_300)) {
smp_ops->cause_ipi = pnv_cause_ipi;
if (cpu_has_feature(CPU_FTR_DBELL)) {
if (cpu_has_feature(CPU_FTR_ARCH_300)) {
if (cpu_has_feature(CPU_FTR_POWER9_DD1))
smp_ops->cause_ipi = pnv_p9_dd1_cause_ipi;
else
smp_ops->cause_ipi = doorbell_global_ipi;
} else {
smp_ops->cause_ipi = pnv_cause_ipi;
}
} else {
smp_ops->cause_ipi = icp_ops->cause_ipi;
}