* [Qemu-devel] [PATCH] i8257: fix Terminal Count status
@ 2016-02-25 12:45 Hervé Poussineau
2016-02-26 23:51 ` John Snow
2016-02-29 14:26 ` Paolo Bonzini
0 siblings, 2 replies; 3+ messages in thread
From: Hervé Poussineau @ 2016-02-25 12:45 UTC (permalink / raw)
To: qemu-devel
Cc: Hervé Poussineau, Paolo Bonzini, John Snow,
Michael S. Tsirkin
When a DMA transfer is done (ie all bytes have been transfered), the corresponding
Terminal Count bit must be set in the status register.
This bit is already cleared in i8257_read_cont and i8257_write_cont when required.
This fixes (at least) floppy transfer in IBM 40p firmware, which checks in DMA
controller if everything went fine.
Signed-off-by: Hervé Poussineau <hpoussin@reactos.org>
---
hw/dma/i8257.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/hw/dma/i8257.c b/hw/dma/i8257.c
index 5a52707..6078893 100644
--- a/hw/dma/i8257.c
+++ b/hw/dma/i8257.c
@@ -342,6 +342,10 @@ static void i8257_channel_run(I8257State *d, int ichan)
r->now[COUNT], (r->base[COUNT] + 1) << ncont);
r->now[COUNT] = n;
ldebug ("dma_pos %d size %d\n", n, (r->base[COUNT] + 1) << ncont);
+ if (n == (r->base[COUNT] + 1) << ncont) {
+ ldebug("transfer done\n");
+ d->status |= (1 << ichan);
+ }
}
static void i8257_dma_run(void *opaque)
--
2.1.4
^ permalink raw reply related [flat|nested] 3+ messages in thread* Re: [Qemu-devel] [PATCH] i8257: fix Terminal Count status
2016-02-25 12:45 [Qemu-devel] [PATCH] i8257: fix Terminal Count status Hervé Poussineau
@ 2016-02-26 23:51 ` John Snow
2016-02-29 14:26 ` Paolo Bonzini
1 sibling, 0 replies; 3+ messages in thread
From: John Snow @ 2016-02-26 23:51 UTC (permalink / raw)
To: Hervé Poussineau, qemu-devel; +Cc: Paolo Bonzini, Michael S. Tsirkin
On 02/25/2016 07:45 AM, Hervé Poussineau wrote:
> When a DMA transfer is done (ie all bytes have been transfered), the corresponding
> Terminal Count bit must be set in the status register.
> This bit is already cleared in i8257_read_cont and i8257_write_cont when required.
>
> This fixes (at least) floppy transfer in IBM 40p firmware, which checks in DMA
> controller if everything went fine.
>
> Signed-off-by: Hervé Poussineau <hpoussin@reactos.org>
> ---
> hw/dma/i8257.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/hw/dma/i8257.c b/hw/dma/i8257.c
> index 5a52707..6078893 100644
> --- a/hw/dma/i8257.c
> +++ b/hw/dma/i8257.c
> @@ -342,6 +342,10 @@ static void i8257_channel_run(I8257State *d, int ichan)
> r->now[COUNT], (r->base[COUNT] + 1) << ncont);
> r->now[COUNT] = n;
> ldebug ("dma_pos %d size %d\n", n, (r->base[COUNT] + 1) << ncont);
> + if (n == (r->base[COUNT] + 1) << ncont) {
> + ldebug("transfer done\n");
> + d->status |= (1 << ichan);
> + }
> }
>
> static void i8257_dma_run(void *opaque)
>
As best as I can tell from the i8257 data sheet I found this seems to be
correct, assuming the size calculation is correct (looks right, based on
that existing ldebug print.)
Reviewed-by: John Snow <jsnow@redhat.com>
^ permalink raw reply [flat|nested] 3+ messages in thread* Re: [Qemu-devel] [PATCH] i8257: fix Terminal Count status
2016-02-25 12:45 [Qemu-devel] [PATCH] i8257: fix Terminal Count status Hervé Poussineau
2016-02-26 23:51 ` John Snow
@ 2016-02-29 14:26 ` Paolo Bonzini
1 sibling, 0 replies; 3+ messages in thread
From: Paolo Bonzini @ 2016-02-29 14:26 UTC (permalink / raw)
To: Hervé Poussineau, qemu-devel; +Cc: John Snow, Michael S. Tsirkin
On 25/02/2016 13:45, Hervé Poussineau wrote:
> When a DMA transfer is done (ie all bytes have been transfered), the corresponding
> Terminal Count bit must be set in the status register.
> This bit is already cleared in i8257_read_cont and i8257_write_cont when required.
>
> This fixes (at least) floppy transfer in IBM 40p firmware, which checks in DMA
> controller if everything went fine.
>
> Signed-off-by: Hervé Poussineau <hpoussin@reactos.org>
> ---
> hw/dma/i8257.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/hw/dma/i8257.c b/hw/dma/i8257.c
> index 5a52707..6078893 100644
> --- a/hw/dma/i8257.c
> +++ b/hw/dma/i8257.c
> @@ -342,6 +342,10 @@ static void i8257_channel_run(I8257State *d, int ichan)
> r->now[COUNT], (r->base[COUNT] + 1) << ncont);
> r->now[COUNT] = n;
> ldebug ("dma_pos %d size %d\n", n, (r->base[COUNT] + 1) << ncont);
> + if (n == (r->base[COUNT] + 1) << ncont) {
> + ldebug("transfer done\n");
> + d->status |= (1 << ichan);
> + }
> }
>
> static void i8257_dma_run(void *opaque)
>
Queued, thanks!
Paolo
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2016-02-29 14:27 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2016-02-25 12:45 [Qemu-devel] [PATCH] i8257: fix Terminal Count status Hervé Poussineau
2016-02-26 23:51 ` John Snow
2016-02-29 14:26 ` Paolo Bonzini
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).