Release secondary cores from WFI (wait for interrupt) by sending them
an IPI. This does not work however yet in QEMU. As a temporary workaround set software interrupt pending bit manually on a local core to ensure WFI doesn't halt the hart. This is required to smpboot in QEMU. Sponsored by: DARPA, AFRL
This commit is contained in:
parent
4fe984fdae
commit
f2e299880a
Notes:
svn2git
2020-12-20 02:59:44 +00:00
svn path=/head/; revision=335005
@ -181,6 +181,7 @@ riscv64_cpu_attach(device_t dev)
|
||||
static void
|
||||
release_aps(void *dummy __unused)
|
||||
{
|
||||
uintptr_t mask;
|
||||
int cpu, i;
|
||||
|
||||
if (mp_ncpus == 1)
|
||||
@ -191,6 +192,14 @@ release_aps(void *dummy __unused)
|
||||
|
||||
atomic_store_rel_int(&aps_ready, 1);
|
||||
|
||||
/* Wake up the other CPUs */
|
||||
mask = 0;
|
||||
|
||||
for (i = 1; i < mp_ncpus; i++)
|
||||
mask |= (1 << i);
|
||||
|
||||
sbi_send_ipi(&mask);
|
||||
|
||||
printf("Release APs\n");
|
||||
|
||||
for (i = 0; i < 2000; i++) {
|
||||
@ -217,6 +226,11 @@ init_secondary(uint64_t cpu)
|
||||
pcpup = &__pcpu[cpu];
|
||||
__asm __volatile("mv gp, %0" :: "r"(pcpup));
|
||||
|
||||
/* Workaround: make sure wfi doesn't halt the hart */
|
||||
intr_disable();
|
||||
csr_set(sie, SIE_SSIE);
|
||||
csr_set(sip, SIE_SSIE);
|
||||
|
||||
/* Spin until the BSP releases the APs */
|
||||
while (!aps_ready)
|
||||
__asm __volatile("wfi");
|
||||
|
Loading…
Reference in New Issue
Block a user