/**
* Check the cmd register to see if we should start or stop
* the DMA or FIS RX engines.
*
* @ad: Device to engage.
* @allow_stop: Allow device to transition from started to stopped?
* 'no' is useful for migration post_load, which does not expect a transition.
*
* @return 0 on success, -1 on error.
*/
static int ahci_cond_start_engines(AHCIDevice *ad, bool allow_stop)
{
AHCIPortRegs *pr = &ad->port_regs;
if (pr->cmd & PORT_CMD_START) {
if (ahci_map_clb_address(ad)) {
pr->cmd |= PORT_CMD_LIST_ON;
} else {
error_report("AHCI: Failed to start DMA engine: "
"bad command list buffer address");
return -1;
}
} else if (pr->cmd & PORT_CMD_LIST_ON) {
if (allow_stop) {
ahci_unmap_clb_address(ad);
pr->cmd = pr->cmd & ~(PORT_CMD_LIST_ON);
} else {
error_report("AHCI: DMA engine should be off, "
"but appears to still be running");
return -1;
}
}
if (pr->cmd & PORT_CMD_FIS_RX) {
if (ahci_map_fis_address(ad)) {
pr->cmd |= PORT_CMD_FIS_ON;
} else {
error_report("AHCI: Failed to start FIS receive engine: "
"bad FIS receive buffer address");
return -1;
}
} else if (pr->cmd & PORT_CMD_FIS_ON) {
if (allow_stop) {
ahci_unmap_fis_address(ad);
pr->cmd = pr->cmd & ~(PORT_CMD_FIS_ON);
} else {
error_report("AHCI: FIS receive engine should be off, "
"but appears to still be running");
return -1;
}
}
return 0;
}
static void ahci_port_write(AHCIState *s, int port, int offset, uint32_t val)
{
AHCIPortRegs *pr = &s->dev[port].port_regs;
DPRINTF(port, "offset: 0x%x val: 0x%x\n", offset, val);
switch (offset) {
case PORT_LST_ADDR:
pr->lst_addr = val;
break;
case PORT_LST_ADDR_HI:
pr->lst_addr_hi = val;
break;
case PORT_FIS_ADDR:
pr->fis_addr = val;
break;
case PORT_FIS_ADDR_HI:
pr->fis_addr_hi = val;
break;
case PORT_IRQ_STAT:
pr->irq_stat &= ~val;
ahci_check_irq(s);
break;
case PORT_IRQ_MASK:
pr->irq_mask = val & 0xfdc000ff;
ahci_check_irq(s);
break;
case PORT_CMD:
/* Block any Read-only fields from being set;
* including LIST_ON and FIS_ON. */
pr->cmd = (pr->cmd & PORT_CMD_RO_MASK) | (val & ~PORT_CMD_RO_MASK);
if (pr->cmd & PORT_CMD_START) {
if (ahci_map_clb_address(&s->dev[port])) {
pr->cmd |= PORT_CMD_LIST_ON;
} else {
error_report("AHCI: Failed to start DMA engine: "
"bad command list buffer address");
}
} else if (pr->cmd & PORT_CMD_LIST_ON) {
ahci_unmap_clb_address(&s->dev[port]);
pr->cmd = pr->cmd & ~(PORT_CMD_LIST_ON);
}
if (pr->cmd & PORT_CMD_FIS_RX) {
if (ahci_map_fis_address(&s->dev[port])) {
pr->cmd |= PORT_CMD_FIS_ON;
} else {
error_report("AHCI: Failed to start FIS receive engine: "
"bad FIS receive buffer address");
}
} else if (pr->cmd & PORT_CMD_FIS_ON) {
ahci_unmap_fis_address(&s->dev[port]);
pr->cmd = pr->cmd & ~(PORT_CMD_FIS_ON);
}
/* XXX usually the FIS would be pending on the bus here and
issuing deferred until the OS enables FIS receival.
Instead, we only submit it once - which works in most
cases, but is a hack. */
if ((pr->cmd & PORT_CMD_FIS_ON) &&
!s->dev[port].init_d2h_sent) {
ahci_init_d2h(&s->dev[port]);
s->dev[port].init_d2h_sent = true;
}
check_cmd(s, port);
break;
case PORT_TFDATA:
/* Read Only. */
break;
case PORT_SIG:
/* Read Only */
break;
case PORT_SCR_STAT:
/* Read Only */
break;
case PORT_SCR_CTL:
if (((pr->scr_ctl & AHCI_SCR_SCTL_DET) == 1) &&
((val & AHCI_SCR_SCTL_DET) == 0)) {
ahci_reset_port(s, port);
}
pr->scr_ctl = val;
break;
case PORT_SCR_ERR:
pr->scr_err &= ~val;
break;
case PORT_SCR_ACT:
/* RW1 */
pr->scr_act |= val;
break;
case PORT_CMD_ISSUE:
pr->cmd_issue |= val;
check_cmd(s, port);
break;
default:
break;
}
}
