[SimNow] PORT_IRQ_STAT register is 0 in ahci_port_setup

[WANG Siyuan]

Hi,
I am trying to boot a hard disk image using coreboot and seabios on
SimNow Simulator.
The system stops at seabios stage.

PORT_CMD_START fails in function ahci_port_setup (seabios/src/ahci.c),
Then I traced into function ahci_command (seabios/src/ahci.c), I found
the value of register ORT_IRQ_STAT is always 0:
intbits = ahci_port_readl(ctrl, pnr, PORT_IRQ_STAT);
intbits returns 0 all the time, so system stops here until time out.

Any comments would be appreciated.
--
Yours sincerely,
WANG Siyuan