Commit bf16cc8f97ff57db191eec73346ba0333ade342b
1 parent
dc1ded53
e1000: Fix RX descriptor low threshold interrupt logic (Alex Williamson)
The RXDMT0 interrupt is supposed to fire when the number of free RX descriptors drops to some fraction of the total descriptors. However in practice, it seems like we're adding this interrupt cause on every RX. Fix the logic to treat (tail - head) as the number of free entries rather than the number of used entries. Signed-off-by: Alex Williamson <alex.williamson@hp.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6864 c046a42c-6fe2-441c-8c8c-71466251a162
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2 deletions
hw/e1000.c
| ... | ... | @@ -666,8 +666,8 @@ e1000_receive(void *opaque, const uint8_t *buf, int size) |
| 666 | 666 | n = E1000_ICS_RXT0; |
| 667 | 667 | if ((rdt = s->mac_reg[RDT]) < s->mac_reg[RDH]) |
| 668 | 668 | rdt += s->mac_reg[RDLEN] / sizeof(desc); |
| 669 | - if (((rdt - s->mac_reg[RDH]) * sizeof(desc)) << s->rxbuf_min_shift >= | |
| 670 | - s->mac_reg[RDLEN]) | |
| 669 | + if (((rdt - s->mac_reg[RDH]) * sizeof(desc)) <= s->mac_reg[RDLEN] >> | |
| 670 | + s->rxbuf_min_shift) | |
| 671 | 671 | n |= E1000_ICS_RXDMT0; |
| 672 | 672 | |
| 673 | 673 | set_ics(s, 0, n); | ... | ... |