b43: Add panic reason code that doesn't trigger restart
Add a firmware panic reason code that doesn't trigger a restart.
This is useful for firmware debugging and avoiding endless
restart loops. We can use FWPANIC_DIE to halt the firmware at a
well defined point.
Signed-off-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/b43/b43.h b/drivers/net/wireless/b43/b43.h
index f588dfa..f0041750 100644
--- a/drivers/net/wireless/b43/b43.h
+++ b/drivers/net/wireless/b43/b43.h
@@ -422,12 +422,21 @@
B43_IRQ_RFKILL | \
B43_IRQ_TX_OK)
+/* The firmware register to fetch the debug-IRQ reason from. */
+#define B43_DEBUGIRQ_REASON_REG 63
/* Debug-IRQ reasons. */
#define B43_DEBUGIRQ_PANIC 0 /* The firmware panic'ed */
#define B43_DEBUGIRQ_DUMP_SHM 1 /* Dump shared SHM */
#define B43_DEBUGIRQ_DUMP_REGS 2 /* Dump the microcode registers */
#define B43_DEBUGIRQ_ACK 0xFFFF /* The host writes that to ACK the IRQ */
+/* The firmware register to fetch the panic reason from. */
+#define B43_FWPANIC_REASON_REG 3
+/* Firmware panic reason codes */
+#define B43_FWPANIC_DIE 0 /* Firmware died. Don't auto-restart it. */
+#define B43_FWPANIC_RESTART 1 /* Firmware died. Schedule a controller reset. */
+
+
/* Device specific rate values.
* The actual values defined here are (rate_in_mbps * 2).
* Some code depends on this. Don't change it. */
diff --git a/drivers/net/wireless/b43/main.c b/drivers/net/wireless/b43/main.c
index 6011747..e1dfb40 100644
--- a/drivers/net/wireless/b43/main.c
+++ b/drivers/net/wireless/b43/main.c
@@ -1662,6 +1662,30 @@
b43dbg(dev->wl, "Set beacon interval to %u\n", beacon_int);
}
+static void b43_handle_firmware_panic(struct b43_wldev *dev)
+{
+ u16 reason;
+
+ /* Read the register that contains the reason code for the panic. */
+ reason = b43_shm_read16(dev, B43_SHM_SCRATCH, B43_FWPANIC_REASON_REG);
+ b43err(dev->wl, "Whoopsy, firmware panic! Reason: %u\n", reason);
+
+ switch (reason) {
+ default:
+ b43dbg(dev->wl, "The panic reason is unknown.\n");
+ /* fallthrough */
+ case B43_FWPANIC_DIE:
+ /* Do not restart the controller or firmware.
+ * The device is nonfunctional from now on.
+ * Restarting would result in this panic to trigger again,
+ * so we avoid that recursion. */
+ break;
+ case B43_FWPANIC_RESTART:
+ b43_controller_restart(dev, "Microcode panic");
+ break;
+ }
+}
+
static void handle_irq_ucode_debug(struct b43_wldev *dev)
{
unsigned int i, cnt;
@@ -1672,15 +1696,12 @@
if (!dev->fw.opensource)
return;
- /* Microcode register 63 contains the debug-IRQ reason. */
- reason = b43_shm_read16(dev, B43_SHM_SCRATCH, 63);
+ /* Read the register that contains the reason code for this IRQ. */
+ reason = b43_shm_read16(dev, B43_SHM_SCRATCH, B43_DEBUGIRQ_REASON_REG);
+
switch (reason) {
case B43_DEBUGIRQ_PANIC:
- /* The reason for the panic is in register 3. */
- reason = b43_shm_read16(dev, B43_SHM_SCRATCH, 3);
- b43err(dev->wl, "Whoopsy, the microcode panic'ed! Reason: %u\n",
- reason);
- b43_controller_restart(dev, "Microcode panic");
+ b43_handle_firmware_panic(dev);
break;
case B43_DEBUGIRQ_DUMP_SHM:
if (!B43_DEBUG)
@@ -1721,7 +1742,9 @@
reason);
}
out:
- b43_shm_write16(dev, B43_SHM_SCRATCH, 63, B43_DEBUGIRQ_ACK);
+ /* Acknowledge the debug-IRQ, so the firmware can continue. */
+ b43_shm_write16(dev, B43_SHM_SCRATCH,
+ B43_DEBUGIRQ_REASON_REG, B43_DEBUGIRQ_ACK);
}
/* Interrupt handler bottom-half */