Re: [Qemu-devel] hw/esp.c mishandles commands without dma

[Martin Husemann <martin@duskware.de>]

On Sun, Jun 17, 2012 at 11:55:20PM +0200, Martin Husemann wrote:
> The NetBSD driver sometimes uses commands without DMA (for example a simple
> TEST_UNIT_READY). On esp hardware, the command has a DMA bit (if dma is to
> be used), and when writing to the command register, the s->dma status is
> updated accordingly.
> 
> When commands with dma are used and dma is disabled, the command is defered
> untill dma is enabled again. This is all fine. However, the deferal should
> not happen if the command does not use dma.
> 
> This can bee seen by booting NetBSD/sparc: for every scsi device attached
> there will be a 5 second timeout and an error message.
> 
> Here is a trivial patch wich fixes this problem for me:
> 
> --- hw/esp.c.orig	2012-06-01 11:13:13.000000000 +0200
> +++ hw/esp.c	2012-06-18 01:43:34.000000000 +0200
> @@ -270,7 +270,7 @@ static void handle_satn(ESPState *s)
>      uint8_t buf[32];
>      int len;
>  
> -    if (!s->dma_enabled) {
> +    if (s->dma && !s->dma_enabled) {
>          s->dma_cb = handle_satn;
>          return;
>      }
> @@ -284,7 +284,7 @@ static void handle_s_without_atn(ESPStat
>      uint8_t buf[32];
>      int len;
>  
> -    if (!s->dma_enabled) {
> +    if (s->dma && !s->dma_enabled) {
>          s->dma_cb = handle_s_without_atn;
>          return;
>      }
> @@ -296,7 +296,7 @@ static void handle_s_without_atn(ESPStat
>  
>  static void handle_satn_stop(ESPState *s)
>  {
> -    if (!s->dma_enabled) {
> +    if (s->dma && !s->dma_enabled) {
>          s->dma_cb = handle_satn_stop;
>          return;
>      }
> 
> 
> I filed a ticket in the bugtracker for it: #1014099.
> 
> 
> Martin

Forgot to add:

Signed-off-by: Martin Husemann <martin@NetBSD.org>