cadence_gem: Make the revision a property

Expose the Cadence GEM revision as a property.
Signed-off-by: NAlistair Francis <alistair.francis@xilinx.com>
Reviewed-by: NPhilippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 541324373cf87b50f8be0439a0cb89f5028b016f.1491947224.git.alistair.francis@xilinx.com
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

hw/net/cadence_gem.c

@@ -300,6 +300,8 @@
 #define DESC_1_RX_SOF 0x00004000
 #define DESC_1_RX_EOF 0x00008000
 
+#define GEM_MODID_VALUE 0x00020118
+
 static inline unsigned tx_desc_get_buffer(unsigned *desc)
 {
     return desc[0];
@@ -1223,7 +1225,7 @@ static void gem_reset(DeviceState *d)
     s->regs[GEM_TXPAUSE] = 0x0000ffff;
     s->regs[GEM_TXPARTIALSF] = 0x000003ff;
     s->regs[GEM_RXPARTIALSF] = 0x000003ff;
-    s->regs[GEM_MODID] = 0x00020118;
+    s->regs[GEM_MODID] = s->revision;
     s->regs[GEM_DESCONF] = 0x02500111;
     s->regs[GEM_DESCONF2] = 0x2ab13fff;
     s->regs[GEM_DESCONF5] = 0x002f2145;
@@ -1519,6 +1521,8 @@ static const VMStateDescription vmstate_cadence_gem = {
 
 static Property gem_properties[] = {
     DEFINE_NIC_PROPERTIES(CadenceGEMState, conf),
+    DEFINE_PROP_UINT32("revision", CadenceGEMState, revision,
+                       GEM_MODID_VALUE),
     DEFINE_PROP_UINT8("num-priority-queues", CadenceGEMState,
                       num_priority_queues, 1),
     DEFINE_PROP_UINT8("num-type1-screeners", CadenceGEMState,

include/hw/net/cadence_gem.h

@@ -50,6 +50,7 @@ typedef struct CadenceGEMState {
     uint8_t num_priority_queues;
     uint8_t num_type1_screeners;
     uint8_t num_type2_screeners;
+    uint32_t revision;
 
     /* GEM registers backing store */
     uint32_t regs[CADENCE_GEM_MAXREG];