Date: Wed, 18 Jul 2007 08:38:01 +0200 From: Patrick Oeschger <paketix@bluewin.ch> To: freebsd-net@freebsd.org Subject: Re: em(4)/82571eb: fifo not dma'ed to host memory Message-ID: <20070718063801.GA40653@hbnnbsddev03.sharedtcs.net> In-Reply-To: <2a41acea0707170917n56e35cfbyc6e0bca094bfa729@mail.gmail.com> References: <20070717110156.GA37722@hbnnbsddev03.sharedtcs.net> <2a41acea0707170917n56e35cfbyc6e0bca094bfa729@mail.gmail.com>
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thanks for your feedback jack - i tried the MSI stuff as first task this
morning
the interface init'ed without a problem and did not complain about MSI
what i like most is that no IRQ is assigned now, everything seems to get
handled in a TASKQ (IRQs were quite weird sometimes when having a bunch of
interfaces...)
but now the bad news: even with MSI it is not possible to recv any frames
what makes me curious is, that the head pointer for receive fifo is *not*
counting up after receiving a frame (good_packets counter incrementing)
as far as i understand the 82571EB chipset manual, recv head counter inc
is done in hardware after receiving a good_packet and having dma'ed it to
host memory
from if_em.c/em_process_receive_interrupts:
* This routine executes in interrupt context. It replenishes
* the mbufs in the descriptor and sends data which has been
* dma'ed into host memory to upper layer.
i did a quick test to check this on 6.1-RELENG by inserting a return
at the top of em_process_receive_interrupts (see diff)
register RDH0 is still incrementing for each good_packet received - even
without receive interrupts being processed at the driver level
freebsd61# sysctl dev.em.0.debug_info=1
dev.em.0.debug_iemnfo: 0:-1 Adapter hardware address = 0xc4b7c928
em0: CTRL = 0x81c0241 RCTL = 0x8002
em0: RDBAH0 = 0x0 RDBAL0 = 0x3e0ff000
em0: RDLEN0 = 0x1000 RDH0 = 0x3
em0: RDT0 = 0xff RXDCTL = 0x10000
...so IMHO this increment (and also dma transfer to host memory) is done
in hardware - RDH0 is not counting up when running under 7.0-CURRENT...
erroneous init of chipset?
anyone else running 7.0-CURRENT on a 82571EB pci express chipset?
TIA for any help on this
pat
details for dmesg/if_stats/diff:
pcib9: <PCI-PCI bridge> irq 19 at device 11.0 on pci2
pcib9: secondary bus 9
pcib9: subordinate bus 9
pcib9: I/O decode 0x6000-0x6fff
pcib9: memory decode 0xfd700000-0xfd7fffff
pcib9: prefetched decode 0xfce00000-0xfcefffff
pci9: <PCI bus> on pcib9
pci9: physical bus=9
found-> vendor=0x8086, dev=0x105e, revid=0x06
bus=9, slot=0, func=0
class=02-00-00, hdrtype=0x00, mfdev=1
cmdreg=0x0000, statreg=0x0010, cachelnsz=16 (dwords)
lattimer=0x00 (0 ns), mingnt=0x00 (0 ns), maxlat=0x00 (0 ns)
intpin=a, irq=255
powerspec 2 supports D0 D3 current D0
MSI supports 1 message, 64 bit
map[10]: type Memory, range 32, base 0, size 17, memory disabled
map[14]: type Memory, range 32, base 0, size 17, memory disabled
map[18]: type I/O Port, range 32, base 0, size 5, port disabled
found-> vendor=0x8086, dev=0x105e, revid=0x06
bus=9, slot=0, func=1
class=02-00-00, hdrtype=0x00, mfdev=1
cmdreg=0x0000, statreg=0x0010, cachelnsz=16 (dwords)
lattimer=0x00 (0 ns), mingnt=0x00 (0 ns), maxlat=0x00 (0 ns)
intpin=b, irq=255
powerspec 2 supports D0 D3 current D0
MSI supports 1 message, 64 bit
map[10]: type Memory, range 32, base 0, size 17, memory disabled
map[14]: type Memory, range 32, base 0, size 17, memory disabled
map[18]: type I/O Port, range 32, base 0, size 5, port disabled
em0: <Intel(R) PRO/1000 Network Connection Version - 6.5.3> at device
0.0 on pci9
pcib9: em0 requested memory range 0xfd700000-0xfd7fffff: good
pcib2: em0 requested memory range 0xfd700000-0xfd7fffff: good
pcib1: em0 requested memory range 0xfd700000-0xfd7fffff: good
em0: Lazy allocation of 0x20000 bytes rid 0x10 type 3 at 0xfd700000
em0: attempting to allocate 1 MSI vectors (1 supported)
msi: routing MSI IRQ 256 to vector 49
em0: using IRQ 256 for MSI
em0: bpf attached
em0: Ethernet address: 00:10:f3:0c:5b:2a
em0: [FILTER]
pci9: <network, ethernet> at device 0.1 (no driver attached)
freebsd61# diff -u sys/dev/em/if_em.c.orig sys/dev/em/if_em.c
--- sys/dev/em/if_em.c.orig Wed Jul 18 07:32:53 2007
+++ sys/dev/em/if_em.c Wed Jul 18 07:48:42 2007
@@ -277,6 +277,11 @@
INIT_DEBUGOUT("em_probe: begin");
+ // prevent init of all em(4) devices except pci9/0/0
+ if(pci_get_bus(dev) != 0x09 || pci_get_slot(dev) != 0x00 ||
+ pci_get_function(dev) != 0x00)
+ return (ENXIO);
+
pci_vendor_id = pci_get_vendor(dev);
if (pci_vendor_id != EM_VENDOR_ID)
return(ENXIO);
@@ -2906,6 +2911,8 @@
u_int8_t eop = 0;
u_int16_t len, desc_len, prev_len_adj;
int i;
+
+ return;
/* Pointer to the receive descriptor being examined. */
struct em_rx_desc *current_desc;
On Tue, Jul 17, 2007 at 09:17:36AM -0700, Jack Vogel wrote:
> As an experiment, search in if_em.c for 'msix' look at the logic there.
> If the adapter is 82575 it will use msix, but the else clause has it
> use msi ONLY if its '>82571', change that to >=82571 and let's
> see if maybe using MSI will help you with your problems as I'm
> pretty confident its interrupt related.
>
> I had intended on making this change shortly anyway, my tests
> have shown the 571 to work fine this way.
>
> Let me know of the results.
>
> Jack
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