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PCI burst writes to OPENCORE PC slave are STOPedafter6words.
by Unknown on Oct 19, 2004 |
Not available! | ||
|
What's the value of your PCIW_ADDR_LENGTH define?
This is the one that actually sets the FIFO depth, the other two
are used for RAM instances (and they limit the maximum FIFO depth you can
set).
Regards,
Miha Dolenc
----- Original Message -----
From: "Dave Warren" dave@luscher.co.uk>
To: "Discussion list about free,open source PCI IP core" pci@opencores.org>
Sent: Tuesday, October 19, 2004 10:50 AM
Subject: Re: [pci] PCI burst writes to OPENCORE PC slave are
STOPedafter6words.
Hi Miha,
My PCI fifo size was 128 words, also it is not shared so 6 seems a small
number for the burst. I will recompile with 256 words to see if the burst
size changes.
`define PCI_FIFO_RAM_ADDR_LENGTH 7
`define PCI_RAM_DONT_SHARE
regards
Dave Warren
----- Original Message -----
From: "Miha Dolenc" mihad@opencores.org>
To: "Discussion list about free, open source PCI IP core"
pci@opencores.org>
Sent: Tuesday, October 19, 2004 8:24 AM
Subject: Re: [pci] PCI burst writes to OPENCORE PC slave are STOPed
after6words.
> Hi!
>
> Have you tried increasing the FIFO size?
>
> Regards,
> Miha Dolenc
>
> ----- Original Message -----
> From: "Dave Warren" dave@luscher.co.uk>
> To: pci@opencores.org>
> Sent: Monday, October 18, 2004 4:53 PM
> Subject: [pci] PCI burst writes to OPENCORE PC slave are STOPed after
> 6words.
>
>
>
> I have the PCI core configured as a PCI slave, wishbone master. The > transfer
> rate for large burst transfers is disappointing. My PCI bus is clocked
at
> 33Mhz, wishbone at 40Mhz. Data is written by an external PCI master
which
> can write long bursts, up to 256 words. The PCI target is the OPENCORE
PCI
> bridge, the wishbone target is an internal FIFO which means no wait
> states.
>
> However after six words have been written the OPENCORE PCI generates STOP
> halting the transfer. The external master starts another burst, this
also
> is
_______________________________________________
http://www.opencores.org/mailman/listinfo/pci
> STOPped after six words. So my overall PCI data rate is very poor.
>
> Is there any way to get longer bursts to work?
>
> Dave Warren
>
> dave@luscher.co.uk
>
>
> _______________________________________________
> http://www.opencores.org/mailman/listinfo/pci
>
> _______________________________________________
> http://www.opencores.org/mailman/listinfo/pci
>
|
|||
|
PCI burst writes to OPENCORE PC slave are STOPedafter6words.
by Unknown on Oct 19, 2004 |
Not available! | ||
|
Oh, maybe just one more suggestion - if it is possible for your application,
try splitting up the 256 dword burst to multiple 16 or 32 dword bursts when
using FIFO depth of 128.
This way the PCI Target and WB Master will work simultaneously and probably
achieve better performance.
Regards,
Miha Dolenc
----- Original Message -----
From: "Dave Warren" dave@luscher.co.uk>
To: "Discussion list about free,open source PCI IP core" pci@opencores.org>
Sent: Tuesday, October 19, 2004 10:50 AM
Subject: Re: [pci] PCI burst writes to OPENCORE PC slave are
STOPedafter6words.
Hi Miha,
My PCI fifo size was 128 words, also it is not shared so 6 seems a small
number for the burst. I will recompile with 256 words to see if the burst
size changes.
`define PCI_FIFO_RAM_ADDR_LENGTH 7
`define PCI_RAM_DONT_SHARE
regards
Dave Warren
----- Original Message -----
From: "Miha Dolenc" mihad@opencores.org>
To: "Discussion list about free, open source PCI IP core"
pci@opencores.org>
Sent: Tuesday, October 19, 2004 8:24 AM
Subject: Re: [pci] PCI burst writes to OPENCORE PC slave are STOPed
after6words.
> Hi!
>
> Have you tried increasing the FIFO size?
>
> Regards,
> Miha Dolenc
>
> ----- Original Message -----
> From: "Dave Warren" dave@luscher.co.uk>
> To: pci@opencores.org>
> Sent: Monday, October 18, 2004 4:53 PM
> Subject: [pci] PCI burst writes to OPENCORE PC slave are STOPed after
> 6words.
>
>
>
> I have the PCI core configured as a PCI slave, wishbone master. The > transfer
> rate for large burst transfers is disappointing. My PCI bus is clocked
at
> 33Mhz, wishbone at 40Mhz. Data is written by an external PCI master
which
> can write long bursts, up to 256 words. The PCI target is the OPENCORE
PCI
> bridge, the wishbone target is an internal FIFO which means no wait
> states.
>
> However after six words have been written the OPENCORE PCI generates STOP
> halting the transfer. The external master starts another burst, this
also
> is
_______________________________________________
http://www.opencores.org/mailman/listinfo/pci
> STOPped after six words. So my overall PCI data rate is very poor.
>
> Is there any way to get longer bursts to work?
>
> Dave Warren
>
> dave@luscher.co.uk
>
>
> _______________________________________________
> http://www.opencores.org/mailman/listinfo/pci
>
> _______________________________________________
> http://www.opencores.org/mailman/listinfo/pci
>
|
|||
|
PCI burst writes to OPENCORE PC slave are STOPedafter6words.
by Unknown on Oct 19, 2004 |
Not available! | ||
|
Hi Miha,
My PCIW_ADDR_LENGTH was 3, setting it larger made a longer burst. However
I found setting it to 5 gave best results. Wishbone transfer does not start
until the first PCI transfer has completed
Thanks for your help on this
regards
Dave Warren
----- Original Message -----
From: "Miha Dolenc" mihad@opencores.org>
To: "Discussion list about free, open source PCI IP core"
pci@opencores.org>
Sent: Tuesday, October 19, 2004 10:27 AM
Subject: Re: [pci] PCI burst writes to OPENCORE PC slave are
STOPedafter6words.
Oh, maybe just one more suggestion - if it is possible for your
application,
try splitting up the 256 dword burst to multiple 16 or 32 dword bursts
when
using FIFO depth of 128.
This way the PCI Target and WB Master will work simultaneously and probably
achieve better performance.
Regards,
Miha Dolenc
----- Original Message -----
From: "Dave Warren" dave@luscher.co.uk>
To: "Discussion list about free,open source PCI IP core"
pci@opencores.org>
Sent: Tuesday, October 19, 2004 10:50 AM
Subject: Re: [pci] PCI burst writes to OPENCORE PC slave are STOPedafter6words.
> Hi Miha,
> > My PCI fifo size was 128 words, also it is not shared so 6 seems a small > number for the burst. I will recompile with 256 words to see if the burst
> size changes.
>
> `define PCI_FIFO_RAM_ADDR_LENGTH 7
> `define PCI_RAM_DONT_SHARE
>
> regards
>
> Dave Warren
>
> ----- Original Message -----
> From: "Miha Dolenc" mihad@opencores.org>
> To: "Discussion list about free, open source PCI IP core"
> pci@opencores.org>
> Sent: Tuesday, October 19, 2004 8:24 AM
> Subject: Re: [pci] PCI burst writes to OPENCORE PC slave are STOPed
> after6words.
>
>
> Hi!
>
> Have you tried increasing the FIFO size?
>
> Regards,
> Miha Dolenc
>
> ----- Original Message -----
> From: "Dave Warren" dave@luscher.co.uk>
> To: pci@opencores.org>
> Sent: Monday, October 18, 2004 4:53 PM
> Subject: [pci] PCI burst writes to OPENCORE PC slave are STOPed after
> 6words.
>
>
> >
> > I have the PCI core configured as a PCI slave, wishbone master. The > transfer
> > rate for large burst transfers is disappointing. My PCI bus is
clocked
> at
> > 33Mhz, wishbone at 40Mhz. Data is written by an external PCI master
> which
> > can write long bursts, up to 256 words. The PCI target is the
OPENCORE
> PCI
_______________________________________________
http://www.opencores.org/mailman/listinfo/pci
> > bridge, the wishbone target is an internal FIFO which means no wait
> states.
> >
> > However after six words have been written the OPENCORE PCI generates > STOP
> > halting the transfer. The external master starts another burst, this
> also
> is
>
>
> _______________________________________________
> http://www.opencores.org/mailman/listinfo/pci
> > STOPped after six words. So my overall PCI data rate is very poor.
> >
> > Is there any way to get longer bursts to work?
> >
> > Dave Warren
> >
> > dave@luscher.co.uk
> >
> >
> > _______________________________________________
> > http://www.opencores.org/mailman/listinfo/pci
>
> _______________________________________________
> http://www.opencores.org/mailman/listinfo/pci
>
|
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