[SPARC64]: Add hypervisor API negotiation and fix console bugs.
Hypervisor interfaces need to be negotiated in order to use
some API calls reliably. So add a small set of interfaces
to request API versions and query current settings.
This allows us to fix some bugs in the hypervisor console:
1) If we can negotiate API group CORE of at least major 1
minor 1 we can use con_read and con_write which can improve
console performance quite a bit.
2) When we do a console write request, we should hold the
spinlock around the whole request, not a byte at a time.
What would happen is that it's easy for output from
different cpus to get mixed with each other.
3) Use consistent udelay() based polling, udelay(1) each
loop with a limit of 1000 polls to handle stuck hypervisor
console.
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/arch/sparc64/kernel/setup.c b/arch/sparc64/kernel/setup.c
index 4510283..dea9c3c 100644
--- a/arch/sparc64/kernel/setup.c
+++ b/arch/sparc64/kernel/setup.c
@@ -269,6 +269,7 @@
void __init sun4v_patch(void)
{
+ extern void sun4v_hvapi_init(void);
struct sun4v_1insn_patch_entry *p1;
struct sun4v_2insn_patch_entry *p2;
@@ -300,6 +301,8 @@
p2++;
}
+
+ sun4v_hvapi_init();
}
#ifdef CONFIG_SMP