[Qemu-devel] [PULL 4/4] hw/net/eepro100: Implement read-only bits in MDI registers

[Stefan Hajnoczi <stefanha@redhat.com>]

From: Peter Maydell <peter.maydell@linaro.org>

Although we defined an eepro100_mdi_mask[] array indicating which bits
in the registers are read-only, we weren't actually doing anything with
it. Make the MDI register-write code use it rather than manually making
register 1 read-only and leaving the rest as reads-as-written. (The
special-case handling of register 0 remains as before since its mask is
all-zeros and the special casing happens before we apply the masking.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1402159924-13853-1-git-send-email-peter.maydell@linaro.org
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 hw/net/eepro100.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/hw/net/eepro100.c b/hw/net/eepro100.c
index aaa3ff2..3263e3f 100644
--- a/hw/net/eepro100.c
+++ b/hw/net/eepro100.c
@@ -1217,7 +1217,6 @@ static void eepro100_write_mdi(EEPRO100State *s)
                 break;
             case 1:            /* Status Register */
                 missing("not writable");
-                data = s->mdimem[reg];
                 break;
             case 2:            /* PHY Identification Register (Word 1) */
             case 3:            /* PHY Identification Register (Word 2) */
@@ -1230,7 +1229,8 @@ static void eepro100_write_mdi(EEPRO100State *s)
             default:
                 missing("not implemented");
             }
-            s->mdimem[reg] = data;
+            s->mdimem[reg] &= eepro100_mdi_mask[reg];
+            s->mdimem[reg] |= data & ~eepro100_mdi_mask[reg];
         } else if (opcode == 2) {
             /* MDI read */
             switch (reg) {
-- 
1.9.3