igb: Clear IMS bits when committing ICR access

The datasheet says contradicting statements regarding ICR accesses so it
is not reliable to determine the behavior of ICR accesses. However,
e1000e does clear IMS bits when reading ICR accesses and Linux also
expects ICR accesses will clear IMS bits according to:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/net/ethernet/intel/igb/igb_main.c?h=v6.2#n8048

Fixes: 3a977deebe ("Intrdocue igb device emulation")
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Reviewed-by: Sriram Yagnaraman <sriram.yagnaraman@est.tech>
Signed-off-by: Jason Wang <jasowang@redhat.com>
(cherry picked from commit f0b1df5c4502b5ec89f83417924935ab201511d0)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>

diff --git a/hw/net/igb_core.c b/hw/net/igb_core.c
index bc7af7963a1da58893a00fa9998c4eb5425112b6..e0ee70d1d73291573f199a7a5d18468111bc151f 100644 (file)
--- a/hw/net/igb_core.c
+++ b/hw/net/igb_core.c
@@ -2451,16 +2451,16 @@ igb_set_ims(IGBCore *core, int index, uint32_t val)
 static void igb_commit_icr(IGBCore *core)
 {
     /*
-     * If GPIE.NSICR = 0, then the copy of IAM to IMS will occur only if at
+     * If GPIE.NSICR = 0, then the clear of IMS will occur only if at
      * least one bit is set in the IMS and there is a true interrupt as
      * reflected in ICR.INTA.
      */
     if ((core->mac[GPIE] & E1000_GPIE_NSICR) ||
         (core->mac[IMS] && (core->mac[ICR] & E1000_ICR_INT_ASSERTED))) {
-        igb_set_ims(core, IMS, core->mac[IAM]);
-    } else {
-        igb_update_interrupt_state(core);
+        igb_clear_ims_bits(core, core->mac[IAM]);
     }
+
+    igb_update_interrupt_state(core);
 }
 
 static void igb_set_icr(IGBCore *core, int index, uint32_t val)