Re: [Qemu-devel] AHCI Port Interrupt Enable register cleaning on soft reset

[Alexander Motin <mav@FreeBSD.org>]

Alexander Graf wrote:
> Am 11.09.2011 um 16:43 schrieb Alexander Motin <mav@FreeBSD.org>:
>> I've found that FreeBSD AHCI driver doesn't work with AHCI hardware
>> emulation of QEMU 0.15.0. I believe the problem is on QEMU's side. As I
>> see, it clears port's Interrupt Enable register each time when reset of
>> any level happens. Is is reasonable for the global controller reset. It
>> is probably not good, but acceptable for FreeBSD driver for the port
>> hard reset. But it is IMO wrong for the device soft reset. None of real
>> hardware I know behaves that way.
>>
>> This patch fixes the problem for me:
>> http://people.freebsd.org/~mav/qemu.ahci.patch
> 
> Ah, cool! So FreeBSD works with AHCI using this patch? 

Yes. I haven't done deep testing to guarantee there is no other issues,
but at least disk is properly detected now.

> Please send it again as an inline patch (if really really hard not 100% important) and add a signed-off-by line (very important) to the patch.

OK. Here it is:

Signed-off-by: Alexander Motin <mav@FreeBSD.org>

--- hw/ide/ahci.c.prev	2011-09-11 16:39:53.000000000 +0300
+++ hw/ide/ahci.c	2011-09-11 16:39:48.000000000 +0300
@@ -505,10 +505,7 @@ static void ahci_reset_port(AHCIState *s
     ide_bus_reset(&d->port);
     ide_state->ncq_queues = AHCI_MAX_CMDS;

-    pr->irq_stat = 0;
-    pr->irq_mask = 0;
     pr->scr_stat = 0;
-    pr->scr_ctl = 0;
     pr->scr_err = 0;
     pr->scr_act = 0;
     d->busy_slot = -1;
@@ -1157,12 +1154,17 @@ void ahci_uninit(AHCIState *s)
 void ahci_reset(void *opaque)
 {
     struct AHCIPCIState *d = opaque;
+    AHCIPortRegs *pr;
     int i;

     d->ahci.control_regs.irqstatus = 0;
     d->ahci.control_regs.ghc = 0;

     for (i = 0; i < d->ahci.ports; i++) {
+        pr = &d->ahci.dev[i].port_regs;
+        pr->irq_stat = 0;
+        pr->irq_mask = 0;
+        pr->scr_ctl = 0;
         ahci_reset_port(&d->ahci, i);
     }
 }

-- 
Alexander Motin