bt: Remove B_BUSY state
The bt layer used to cache the value of B_BUSY in the state machine,
assuming that once B_BUSY was cleared by the BMC that it would never
be set by the BMC again unless a message was sent to the bt interface.
This was mostly true for the AMI firmware except when the BMC reboots
which causes B_BUSY to be set. There may also be additional
circumstances which set B_BUSY. Therefore the bt layer must check
B_BUSY is clear before sending a message making the B_BUSY state
superfluous.
Signed-off-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Stewart Smith <stewart@linux.vnet.ibm.com>
diff --git a/hw/bt.c b/hw/bt.c
index 8df31a3..a317421 100644
--- a/hw/bt.c
+++ b/hw/bt.c
@@ -78,7 +78,6 @@
enum bt_states {
BT_STATE_IDLE = 0,
BT_STATE_RESP_WAIT,
- BT_STATE_B_BUSY,
};
struct bt_msg {
@@ -149,7 +148,7 @@
/* Take care of a stable H_BUSY if any */
bt_set_h_busy(false);
- bt_set_state(BT_STATE_B_BUSY);
+ bt_set_state(BT_STATE_IDLE);
}
static void bt_reset_interface(void)
@@ -172,13 +171,6 @@
ipmi_msg = &bt_msg->ipmi_msg;
- if (!bt_idle()) {
- BT_ERR(bt_msg, "Interface in unexpected state, attempting reset\n");
- bt_reset_interface();
- unlock(&bt.lock);
- return;
- }
-
/* Send the message */
bt_outb(BT_CTRL_CLR_WR_PTR, BT_CTRL);
@@ -254,7 +246,7 @@
/* A response to a message we no longer care about. */
prlog(PR_INFO, "BT: Nobody cared about a response to an BT/IPMI message\n");
bt_flush_msg();
- bt_set_state(BT_STATE_B_BUSY);
+ bt_set_state(BT_STATE_IDLE);
return;
}
@@ -277,7 +269,7 @@
ipmi_msg->data[i] = bt_inb(BT_HOST2BMC);
bt_set_h_busy(false);
- bt_set_state(BT_STATE_B_BUSY);
+ bt_set_state(BT_STATE_IDLE);
list_del(&bt_msg->link);
bt.queue_len--;
@@ -351,8 +343,8 @@
static void bt_send_and_unlock(void)
{
- if (lpc_ok() &&
- bt.state == BT_STATE_IDLE && !list_empty(&bt.msgq))
+ if (lpc_ok() && bt_idle() && !list_empty(&bt.msgq)
+ && bt.state == BT_STATE_IDLE)
bt_send_msg();
unlock(&bt.lock);
@@ -380,10 +372,6 @@
(bt_ctrl & BT_CTRL_B2H_ATN))
bt_get_resp();
- /* We need to wait for B_BUSY to clear */
- if (bt.state == BT_STATE_B_BUSY && bt_idle())
- bt_set_state(BT_STATE_IDLE);
-
/* Check for sms_atn */
if (bt_inb(BT_CTRL) & BT_CTRL_SMS_ATN) {
bt_outb(BT_CTRL_SMS_ATN, BT_CTRL);
@@ -541,7 +529,7 @@
* The iBT interface comes up in the busy state until the daemon has
* initialised it.
*/
- bt_set_state(BT_STATE_B_BUSY);
+ bt_set_state(BT_STATE_IDLE);
list_head_init(&bt.msgq);
bt.queue_len = 0;
