[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCH] ahci: Force ICC bits in PxCMD to zero
From: |
John Snow |
Subject: |
Re: [Qemu-devel] [PATCH] ahci: Force ICC bits in PxCMD to zero |
Date: |
Fri, 17 Jul 2015 13:47:58 -0400 |
User-agent: |
Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.7.0 |
On 07/16/2015 03:54 PM, Stefan Fritsch wrote:
> The AHCI spec requires that the HBA sets the ICC bits to zero after the
> ICC change is done. Since we don't do any ICC change, force the bits to
> zero all the time.
>
> This fixes delays with some OSs (e.g. OpenBSD) waiting for the ICC bits
> to change to 0.
>
> Signed-off-by: Stefan Fritsch <address@hidden>
> ---
> hw/ide/ahci.c | 9 +++++++--
> 1 file changed, 7 insertions(+), 2 deletions(-)
>
> diff --git a/hw/ide/ahci.c b/hw/ide/ahci.c
> index bb6a92f..48749c1 100644
> --- a/hw/ide/ahci.c
> +++ b/hw/ide/ahci.c
> @@ -279,8 +279,13 @@ static void ahci_port_write(AHCIState *s, int port, int
> offset, uint32_t val)
> 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);
> + * including LIST_ON and FIS_ON.
> + * The spec requires to set ICC bits to zero after the ICC change
> + * is done. We don't support ICC state changes, therefore always
> + * force the ICC bits to zero.
> + */
> + pr->cmd = (pr->cmd & PORT_CMD_RO_MASK) |
> + (val & ~(PORT_CMD_RO_MASK|PORT_CMD_ICC_MASK));
>
> /* Check FIS RX and CLB engines, allow transition to false: */
> ahci_cond_start_engines(&s->dev[port], true);
>
I guess I'll need to start testing with OpenBSD...
Looks good to me -- (If there's a next time, please also CC qemu-devel
so patch management tools pick this up.)
Reviewed-by: John Snow <address@hidden>
and:
Thanks, applied to my IDE tree:
https://github.com/jnsnow/qemu/commits/ide
https://github.com/jnsnow/qemu.git
--js
[Prev in Thread] |
Current Thread |
[Next in Thread] |
- Re: [Qemu-devel] [PATCH] ahci: Force ICC bits in PxCMD to zero,
John Snow <=