Correct the comments in am7990_intr() and am79900_intr(); it's not

possible to end up in the interrupt handler again while processing the
previous RX interrupt in ifp->if_input() because the MD interrupt code
disables the delivery of the respective interrupt until all associated
handlers were called (in the INTR_FILTER case the MI code supposedly
does the same). Toggling the NIC interrupt enable bit in these handlers
still is necessary though as some chips (f.e. the VMware emulated one)
require this to be done in order to keep issuing interrupts.

MFC after:	1 month

2 files changed, 6 insertions, 8 deletions

diff --git a/sys/dev/le/am7990.c b/sys/dev/le/am7990.c
index 10a809d..56a07d5 100644
--- a/sys/dev/le/am7990.c
+++ b/sys/dev/le/am7990.c
@@ -421,10 +421,9 @@ am7990_intr(void *arg)
 	 * Clear interrupt source flags and turn off interrupts. If we
 	 * don't clear these flags before processing their sources we
 	 * could completely miss some interrupt events as the NIC can
-	 * change these flags while we're in this handler. We turn off
-	 * interrupts so we don't get another RX interrupt while still
-	 * processing the previous one in ifp->if_input() with the
-	 * driver lock dropped.
+	 * change these flags while we're in this handler. We toggle
+	 * the interrupt enable bit in order to keep receiving them
+	 * (some chips work without this, some don't).
 	 */
 	(*sc->sc_wrcsr)(sc, LE_CSR0, isr & ~(LE_C0_INEA | LE_C0_TDMD |
 	    LE_C0_STOP | LE_C0_STRT | LE_C0_INIT));
diff --git a/sys/dev/le/am79900.c b/sys/dev/le/am79900.c
index abaed2d..5129eb6 100644
--- a/sys/dev/le/am79900.c
+++ b/sys/dev/le/am79900.c
@@ -459,10 +459,9 @@ am79900_intr(void *arg)
 	 * Clear interrupt source flags and turn off interrupts. If we
 	 * don't clear these flags before processing their sources we
 	 * could completely miss some interrupt events as the NIC can
-	 * change these flags while we're in this handler. We turn off
-	 * interrupts so we don't get another RX interrupt while still
-	 * processing the previous one in ifp->if_input() with the
-	 * driver lock dropped.
+	 * change these flags while we're in this handler. We toggle
+	 * the interrupt enable bit in order to keep receiving them
+	 * (some chips work without this, some don't).
 	 */
 	(*sc->sc_wrcsr)(sc, LE_CSR0, isr & ~(LE_C0_INEA | LE_C0_TDMD |
 	    LE_C0_STOP | LE_C0_STRT | LE_C0_INIT));