[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/entry.S b/arch/sparc64/kernel/entry.S
index c15a3ed..732b77c 100644
--- a/arch/sparc64/kernel/entry.S
+++ b/arch/sparc64/kernel/entry.S
@@ -1843,3 +1843,97 @@
mov %o1, %o0
1: retl
nop
+
+ /* %o0: API group number
+ * %o1: pointer to unsigned long major number storage
+ * %o2: pointer to unsigned long minor number storage
+ *
+ * returns %o0: status
+ */
+ .globl sun4v_get_version
+sun4v_get_version:
+ mov HV_CORE_GET_VER, %o5
+ mov %o1, %o3
+ mov %o2, %o4
+ ta HV_CORE_TRAP
+ stx %o1, [%o3]
+ retl
+ stx %o2, [%o4]
+
+ /* %o0: API group number
+ * %o1: desired major number
+ * %o2: desired minor number
+ * %o3: pointer to unsigned long actual minor number storage
+ *
+ * returns %o0: status
+ */
+ .globl sun4v_set_version
+sun4v_set_version:
+ mov HV_CORE_SET_VER, %o5
+ mov %o3, %o4
+ ta HV_CORE_TRAP
+ retl
+ stx %o1, [%o4]
+
+ /* %o0: pointer to unsigned long status
+ *
+ * returns %o0: signed character
+ */
+ .globl sun4v_con_getchar
+sun4v_con_getchar:
+ mov %o0, %o4
+ mov HV_FAST_CONS_GETCHAR, %o5
+ clr %o0
+ clr %o1
+ ta HV_FAST_TRAP
+ stx %o0, [%o4]
+ retl
+ sra %o1, 0, %o0
+
+ /* %o0: signed long character
+ *
+ * returns %o0: status
+ */
+ .globl sun4v_con_putchar
+sun4v_con_putchar:
+ mov HV_FAST_CONS_PUTCHAR, %o5
+ ta HV_FAST_TRAP
+ retl
+ sra %o0, 0, %o0
+
+ /* %o0: buffer real address
+ * %o1: buffer size
+ * %o2: pointer to unsigned long bytes_read
+ *
+ * returns %o0: status
+ */
+ .globl sun4v_con_read
+sun4v_con_read:
+ mov %o2, %o4
+ mov HV_FAST_CONS_READ, %o5
+ ta HV_FAST_TRAP
+ brnz %o0, 1f
+ cmp %o1, -1 /* break */
+ be,a,pn %icc, 1f
+ mov %o1, %o0
+ cmp %o1, -2 /* hup */
+ be,a,pn %icc, 1f
+ mov %o1, %o0
+ stx %o1, [%o4]
+1: retl
+ nop
+
+ /* %o0: buffer real address
+ * %o1: buffer size
+ * %o2: pointer to unsigned long bytes_written
+ *
+ * returns %o0: status
+ */
+ .globl sun4v_con_write
+sun4v_con_write:
+ mov %o2, %o4
+ mov HV_FAST_CONS_WRITE, %o5
+ ta HV_FAST_TRAP
+ stx %o1, [%o4]
+ retl
+ nop