b43: Add firmware markers support

This adds support for firmware markers.
With firmware markers it's easily possible to check whether the
firmware runs some codepath or not. The driver will throw a message
when the firmware executes a MARKER(x).
Signed-off-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/b43/b43.h

@@ -428,8 +428,13 @@ enum {
 #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_MARKER		3	/* A "marker" was thrown by the firmware. */
 #define B43_DEBUGIRQ_ACK		0xFFFF	/* The host writes that to ACK the IRQ */
 
+/* The firmware register that contains the "marker" line. */
+#define B43_MARKER_ID_REG		2
+#define B43_MARKER_LINE_REG		3
+
 /* The firmware register to fetch the panic reason from. */
 #define B43_FWPANIC_REASON_REG		3
 /* Firmware panic reason codes */

drivers/net/wireless/b43/main.c

@@ -1689,7 +1689,7 @@ static void b43_handle_firmware_panic(struct b43_wldev *dev)
 static void handle_irq_ucode_debug(struct b43_wldev *dev)
 {
 	unsigned int i, cnt;
-	u16 reason;
+	u16 reason, marker_id, marker_line;
 	__le16 *buf;
 
 	/* The proprietary firmware doesn't have this IRQ. */
@@ -1737,6 +1737,17 @@ static void handle_irq_ucode_debug(struct b43_wldev *dev)
 		}
 		printk("\n");
 		break;
+	case B43_DEBUGIRQ_MARKER:
+		if (!B43_DEBUG)
+			break; /* Only with driver debugging enabled. */
+		marker_id = b43_shm_read16(dev, B43_SHM_SCRATCH,
+					   B43_MARKER_ID_REG);
+		marker_line = b43_shm_read16(dev, B43_SHM_SCRATCH,
+					     B43_MARKER_LINE_REG);
+		b43info(dev->wl, "The firmware just executed the MARKER(%u) "
+			"at line number %u\n",
+			marker_id, marker_line);
+		break;
 	default:
 		b43dbg(dev->wl, "Debug-IRQ triggered for unknown reason: %u\n",
 		       reason);