diff options
authorJason Baron <>2012-09-04 16:08:08 -0400
committerDoug Goldstein <>2012-10-24 02:06:43 -0500
commitc3f02b3326bbdf3f016c3baa1617863d4d85c478 (patch)
parenteepro100: Fix network hang when rx buffers run out (diff)
ahci: properly reset PxCMD on HBA reset
While testing q35, I found that windows 7 (specifically, windows 7 ultimate with sp1 x64), wouldn't install because it can't find the cdrom or disk drive. The failure message is: 'A required cd/dvd device driver is missing. If you have a driver floppy disk, CD, DVD, or USB flash drive, please insert it now.' This can also be reproduced on piix by adding an ahci controller, and observing that windows 7 does not see any devices behind it. The problem is that when windows issues a HBA reset, qemu does not reset the individual ports' PxCMD register. Windows 7 then reads back the PxCMD register and presumably assumes that the ahci controller has already been initialized. Windows then never sets up the PxIE register to enable interrupts, and thus it never gets irqs back when it sends ata device inquiry commands. This change brings qemu into ahci 1.3 specification compliance. Section 10.4.3 HBA Reset: " When GHC.HR is set to '1', GHC.AE, GHC.IE, the IS register, and all port register fields (except PxFB/PxFBU/PxCLB/PxCLBU) that are not HwInit in the HBA's register memory space are reset. " I've also re-tested Fedora 16 and 17 to verify that they continue to work with this change. Signed-off-by: Jason Baron <> Acked-by: Alexander Graf <> Signed-off-by: Kevin Wolf <> (cherry picked from commit 2a4f4f34e6fe55f4c82507c3e7ec9b58c2e24ad4) Conflicts: hw/ide/ahci.c
1 files changed, 1 insertions, 1 deletions
diff --git a/hw/ide/ahci.c b/hw/ide/ahci.c
index 267198e52..1b5b5bf7e 100644
--- a/hw/ide/ahci.c
+++ b/hw/ide/ahci.c
@@ -1168,7 +1168,6 @@ void ahci_init(AHCIState *s, DeviceState *qdev, int ports)
ad->port_no = i;
ad->port.dma = &ad->dma;
ad->port.dma->ops = &ahci_dma_ops;
- ad->port_regs.cmd = PORT_CMD_SPIN_UP | PORT_CMD_POWER_ON;
@@ -1193,6 +1192,7 @@ void ahci_reset(void *opaque)
pr->irq_stat = 0;
pr->irq_mask = 0;
pr->scr_ctl = 0;
ahci_reset_port(&d->ahci, i);