tg3: Fix firmware event timeouts
The git commit 7c5026aa9b81dd45df8d3f4e0be73e485976a8b6 ("tg3: Add
link state reporting to UMP firmware") introduced code that waits for
previous firmware events to be serviced before attempting to submit a
new event. Unfortunately that patch contained a bug that cause the
driver to wait 2.5 seconds, rather than 2.5 milliseconds as intended.
This patch fixes that bug.
This bug revealed that not all firmware versions service driver events
though. Since we do not know which versions of the firmware do and don't
service these events, the driver needs some way to minimize the effects
of the delay. This patch solves the problem by recording a jiffies
timestamp when it submits an event to the hardware. If the jiffies
counter shows that 2.5 milliseconds have already passed, a wait is not
needed and the driver can proceed to submit a new event.
Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/tg3.c b/drivers/net/tg3.c
index e952b91..c26011e 100644
--- a/drivers/net/tg3.c
+++ b/drivers/net/tg3.c
@@ -1020,15 +1020,43 @@
}
/* tp->lock is held. */
+static inline void tg3_generate_fw_event(struct tg3 *tp)
+{
+ u32 val;
+
+ val = tr32(GRC_RX_CPU_EVENT);
+ val |= GRC_RX_CPU_DRIVER_EVENT;
+ tw32_f(GRC_RX_CPU_EVENT, val);
+
+ tp->last_event_jiffies = jiffies;
+}
+
+#define TG3_FW_EVENT_TIMEOUT_USEC 2500
+
+/* tp->lock is held. */
static void tg3_wait_for_event_ack(struct tg3 *tp)
{
int i;
+ unsigned int delay_cnt;
+ long time_remain;
- /* Wait for up to 2.5 milliseconds */
- for (i = 0; i < 250000; i++) {
+ /* If enough time has passed, no wait is necessary. */
+ time_remain = (long)(tp->last_event_jiffies + 1 +
+ usecs_to_jiffies(TG3_FW_EVENT_TIMEOUT_USEC)) -
+ (long)jiffies;
+ if (time_remain < 0)
+ return;
+
+ /* Check if we can shorten the wait time. */
+ delay_cnt = jiffies_to_usecs(time_remain);
+ if (delay_cnt > TG3_FW_EVENT_TIMEOUT_USEC)
+ delay_cnt = TG3_FW_EVENT_TIMEOUT_USEC;
+ delay_cnt = (delay_cnt >> 3) + 1;
+
+ for (i = 0; i < delay_cnt; i++) {
if (!(tr32(GRC_RX_CPU_EVENT) & GRC_RX_CPU_DRIVER_EVENT))
break;
- udelay(10);
+ udelay(8);
}
}
@@ -1077,9 +1105,7 @@
val = 0;
tg3_write_mem(tp, NIC_SRAM_FW_CMD_DATA_MBOX + 12, val);
- val = tr32(GRC_RX_CPU_EVENT);
- val |= GRC_RX_CPU_DRIVER_EVENT;
- tw32_f(GRC_RX_CPU_EVENT, val);
+ tg3_generate_fw_event(tp);
}
static void tg3_link_report(struct tg3 *tp)
@@ -5953,6 +5979,7 @@
tg3_read_mem(tp, NIC_SRAM_DATA_CFG, &nic_cfg);
if (nic_cfg & NIC_SRAM_DATA_CFG_ASF_ENABLE) {
tp->tg3_flags |= TG3_FLAG_ENABLE_ASF;
+ tp->last_event_jiffies = jiffies;
if (tp->tg3_flags2 & TG3_FLG2_5750_PLUS)
tp->tg3_flags2 |= TG3_FLG2_ASF_NEW_HANDSHAKE;
}
@@ -5966,15 +5993,12 @@
{
if ((tp->tg3_flags & TG3_FLAG_ENABLE_ASF) &&
!(tp->tg3_flags3 & TG3_FLG3_ENABLE_APE)) {
- u32 val;
-
/* Wait for RX cpu to ACK the previous event. */
tg3_wait_for_event_ack(tp);
tg3_write_mem(tp, NIC_SRAM_FW_CMD_MBOX, FWCMD_NICDRV_PAUSE_FW);
- val = tr32(GRC_RX_CPU_EVENT);
- val |= GRC_RX_CPU_DRIVER_EVENT;
- tw32(GRC_RX_CPU_EVENT, val);
+
+ tg3_generate_fw_event(tp);
/* Wait for RX cpu to ACK this event. */
tg3_wait_for_event_ack(tp);
@@ -7864,8 +7888,6 @@
if (!--tp->asf_counter) {
if ((tp->tg3_flags & TG3_FLAG_ENABLE_ASF) &&
!(tp->tg3_flags3 & TG3_FLG3_ENABLE_APE)) {
- u32 val;
-
tg3_wait_for_event_ack(tp);
tg3_write_mem(tp, NIC_SRAM_FW_CMD_MBOX,
@@ -7873,9 +7895,8 @@
tg3_write_mem(tp, NIC_SRAM_FW_CMD_LEN_MBOX, 4);
/* 5 seconds timeout */
tg3_write_mem(tp, NIC_SRAM_FW_CMD_DATA_MBOX, 5);
- val = tr32(GRC_RX_CPU_EVENT);
- val |= GRC_RX_CPU_DRIVER_EVENT;
- tw32_f(GRC_RX_CPU_EVENT, val);
+
+ tg3_generate_fw_event(tp);
}
tp->asf_counter = tp->asf_multiplier;
}