[linux-dvb] cx23885 driver and DMA timeouts
stoth at linuxtv.org
Thu Jun 26 00:53:54 CEST 2008
stev391 at email.com wrote:
> I have found the cause of my DMA timeouts, as per your suggestion I
> checked the sram settings.
> The cause of the issue was in SRAM_CH06 cdt, this was originally set to
> 0x10480 and is currently set to 0x108d0. In changeset 7005:a6d2028a4aab
> you introduced this as an alternative set of values and then in
> changeset 7464:20a1412b4f1a it was all converted to these values. I was
> wondering why this value was required to change?
> I have not yet had the time to analyse these values in detail, but the
> following are possible options that I/we can persue:
> 1) Set the value back to 0x10480 (diff attached), the following
> supported cards will use this value (from a quick glance):
> 2) Introduce another variable in struct cx23885_board to allow board
> specific srams. The sram would not be duplicated in this struct, a
> second version would be included in cx23885-core.c (similar to the 7005
> changeset except it is now manual configurable and not switching on PCI
> id). The down side of this is the cx23885-core.c will be slightly
> larger, with a larger memory footprint.
> 3) Reallocate entire sram, this would require a detailed look on my
> behalf to see how much space each variable requires and reallocate it.
> This will potentially break the cards mentioned in option 1 and will
> take more time to implement and test. This is highly undesirable my
> 4) Something else? Please suggest a solution...
> diff -Naur v4l-dvb/linux/drivers/media/video/cx23885/cx23885-core.c
> --- v4l-dvb/linux/drivers/media/video/cx23885/cx23885-core.c
> 2008-06-06 14:57:55.000000000 +1000
> +++ v4l-dvb1/linux/drivers/media/video/cx23885/cx23885-core.c
> 2008-06-26 08:26:42.000000000 +1000
> @@ -142,7 +142,7 @@
> .name = "TS2 C",
> .cmds_start = 0x10140,
> .ctrl_start = 0x10680,
> - .cdt = 0x108d0,
> + .cdt = 0x10480,
> .fifo_start = 0x6000,
> .fifo_size = 0x1000,
> .ptr1_reg = DMA5_PTR1,
> ----- Original Message -----
> From: "Steven Toth"
> To: stev391 at email.com
> Subject: Re: [linux-dvb] cx23885 driver and DMA timeouts
> Date: Mon, 23 Jun 2008 08:51:10 -0400
> No need to try windows, if you have the driver already running
> (pascoe's patches) then your chipset and hardware are fine.
> Sounds like you have a simple merge issue.
> Try to figure out which parts of the merge actually create the
> problem then bring that issue back to this list for discussion.
> - Steve
Let me go back and look at the existing layout. Something is obviously
We don't want board specific values.
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