[Qemu-devel] [PATCH] e1000.c doesn't properly emulate EERD and ICS registers

[Bill Paul]

Once again, the emulation of the EERD and ICS registers in e1000.c is 
incorrect. Nobody has noticed this before because none of the Intel-written 
e1000 drivers use these registers, and all of the independently written open 
source drivers copy Intel's example, so they don't use them either. 
Regardless, these registers are documented in the programmer's manuals, and 
their emulated behavior doesn't match the verified behavior of real hardware, 
so any software that does use them doesn't function correctly.

-Bill


Signed-off-by: Bill Paul <address@hidden>

---

diff --git a/hw/e1000.c b/hw/e1000.c
index 9bc4442..b0542d7 100644
--- a/hw/e1000.c
+++ b/hw/e1000.c
@@ -154,6 +154,7 @@ set_interrupt_cause(E1000State *s, int index, uint32_t 
val)
     if (val)
         val |= E1000_ICR_INT_ASSERTED;
     s->mac_reg[ICR] = val;
+    s->mac_reg[ICS] = val;
     qemu_set_irq(s->dev.irq[0], (s->mac_reg[IMS] & s->mac_reg[ICR]) != 0);
 }
 
@@ -286,10 +287,14 @@ flash_eerd_read(E1000State *s, int x)
 {
     unsigned int index, r = s->mac_reg[EERD] & ~E1000_EEPROM_RW_REG_START;
 
+    if ((s->mac_reg[EERD] & E1000_EEPROM_RW_REG_START) == 0)
+        return (s->mac_reg[EERD]);
+
     if ((index = r >> E1000_EEPROM_RW_ADDR_SHIFT) > EEPROM_CHECKSUM_REG)
-        return 0;
-    return (s->eeprom_data[index] << E1000_EEPROM_RW_REG_DATA) |
-           E1000_EEPROM_RW_REG_DONE | r;
+        return (E1000_EEPROM_RW_REG_DONE | r);
+
+    return ((s->eeprom_data[index] << E1000_EEPROM_RW_REG_DATA) |
+           E1000_EEPROM_RW_REG_DONE | r);
 }
 
 static void
@@ -780,7 +785,7 @@ static uint32_t (*macreg_readops[])(E1000State *, int) = {
     getreg(WUFC),      getreg(TDT),    getreg(CTRL),   getreg(LEDCTL),
     getreg(MANC),      getreg(MDIC),   getreg(SWSM),   getreg(STATUS),
     getreg(TORL),      getreg(TOTL),   getreg(IMS),    getreg(TCTL),
-    getreg(RDH),       getreg(RDT),    getreg(VET),
+    getreg(RDH),       getreg(RDT),    getreg(VET),    getreg(ICS),
 
     [TOTH] = mac_read_clr8,    [TORH] = mac_read_clr8, [GPRC] = mac_read_clr4,
     [GPTC] = mac_read_clr4,    [TPR] = mac_read_clr4,  [TPT] = mac_read_clr4,