* MXC MMC driver and SDIO peripherals
2009-10-28 16:47 ` Daniel Mack
@ 2009-10-28 17:06 ` Dan Williams
2009-10-28 17:19 ` Daniel Mack
2009-10-29 10:27 ` Daniel Mack
2009-10-28 17:11 ` Dan Williams
1 sibling, 2 replies; 14+ messages in thread
From: Dan Williams @ 2009-10-28 17:06 UTC (permalink / raw)
To: linux-arm-kernel
On Wed, 2009-10-28 at 17:47 +0100, Daniel Mack wrote:
> On Wed, Oct 21, 2009 at 01:15:19PM -0700, Dan Williams wrote:
> > On Wed, 2009-10-21 at 21:20 +0200, Daniel Mack wrote:
> > > Hi,
> > >
> > > we're having trouble getting SDIO connected harware to fly on MX31 based
> > > designs. In particular, a SD8686 chip supported by the libertas_sdio
> > > driver will hang forever when built without CONFIG_MMC_DEBUG=y. With
> > > that option selected, however, the behaviour is a little different, and
> > > I can at least see the following messages on a recent 2.6.32-rc5 based
> > > MX31 tree.
> > >
> > > Is there any common pitfall for such setups? I did more or less the same
> > > thing on PXAs (same WLAN chip, same kind of interface, same firmware),
> > > and haven't seen any such effects, so I suspect the MXC specific parts
> > > to be the reason for that. Any ideas?
> >
> > Any idea what quirks your SDHC is using if any? Does it require PIO or
> > can it do DMA? Does it have any transfer restrictions on block size or
> > bit-width? What is the debug output of the MMC stack when loading the
> > module for your SDHC?
>
> I did some more research on this and it turns out that the problem is
> related to multi block transfers. At least, this is when it first
> occurs.
>
> The libertas SDIO driver downloads two firmwares to the device, one
> 'helper' and one 'real' firmware The first one only uses chunks of 64
> bytes each and that seems to work fine. The real firmware, however,
> loads in 512 bytes chunks which the SDIO core breaks up into 16 blocks
> of 32 bytes. And this is where the MXC host controller bails out with a
> CRC error. Unfortunately, it does not give any more detailed information
> about what exactly went wrong.
>
> The effect might be related to an errata entry[1], which is what I'm
> currently investigating. To do so, I would like to limit the the
> communication to singe-block transfers, just to exclude all other
> possible (electrical, clock speed, ...) issues. I did that by setting
> mmc->max_blk_count to 1 in the the host controller, but then again,
> the libertas driver and/or the firmware doesn't like that and dies in
> if_sdio_pro_real() with
>
> firmware wants 17 bytes
> firmware helper signalled error
>
> Any idea how to get that working with only single block small transfers?
All the Marvell documentation (v5 at least) refers to 512-byte transfers
of the second-stage firmware in 32-byte blocks:
Section 2.2.1.1 of the v5 spec states:
"
2) If the length requested by helper is larger than 512 bytes, it is cut
into multiple pieces for CMD53 write. The current download length is set
to 512 bytes (16 blocks x 32 bytes per block) in each iteration of CMD53
write.
3) Host starts the download of 16 blocks of firmware (512 bytes)
4) Host copies the payload to the buffer.
5) Host writes 16 blocks of the firmware image data using CMD 53.
6) Repeat Steps 3 through 5 until the firmware image data specified by
the helper (Step 2) for this iteration is downloaded completely.
"
The helper firmware may well expect all 16 blocks. But try adjusting
"chunk_size" in if_sdio.c::if_sdio_prog_real() down to one block (ie, 32
not 512) and see if the helper pukes. The code looks like it can handle
chunk_size changes just fine.
If it does, and we after we further test that with other v8 and v9
firmware, then maybe we can print out a big fat warning about SDHC
suckage before trying a single-block fallback.
Dan
> Btw - there's a number of things missing for SDIO in the MXC MMC driver
> which I implemented/fixed. I'll send patches as soon as I have more
> confidence about the whole setup.
>
>
> Thanks,
> Daniel
>
>
> [1] Errata IDs TLSbo91748 and TLSbo78667 from
> http://www.freescale.com/files/32bit/doc/errata/MCIMX31CE.pdf?fpsp=1
>
>
> _______________________________________________
> libertas-dev mailing list
> libertas-dev at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/libertas-dev
^ permalink raw reply [flat|nested] 14+ messages in thread
* MXC MMC driver and SDIO peripherals
2009-10-28 17:06 ` Dan Williams
@ 2009-10-28 17:19 ` Daniel Mack
2009-10-28 18:46 ` Dan Williams
2009-10-29 10:27 ` Daniel Mack
1 sibling, 1 reply; 14+ messages in thread
From: Daniel Mack @ 2009-10-28 17:19 UTC (permalink / raw)
To: linux-arm-kernel
On Wed, Oct 28, 2009 at 10:06:02AM -0700, Dan Williams wrote:
> On Wed, 2009-10-28 at 17:47 +0100, Daniel Mack wrote:
> > I did some more research on this and it turns out that the problem is
> > related to multi block transfers. At least, this is when it first
> > occurs.
> >
> > The libertas SDIO driver downloads two firmwares to the device, one
> > 'helper' and one 'real' firmware The first one only uses chunks of 64
> > bytes each and that seems to work fine. The real firmware, however,
> > loads in 512 bytes chunks which the SDIO core breaks up into 16 blocks
> > of 32 bytes. And this is where the MXC host controller bails out with a
> > CRC error. Unfortunately, it does not give any more detailed information
> > about what exactly went wrong.
> >
> > The effect might be related to an errata entry[1], which is what I'm
> > currently investigating. To do so, I would like to limit the the
> > communication to singe-block transfers, just to exclude all other
> > possible (electrical, clock speed, ...) issues. I did that by setting
> > mmc->max_blk_count to 1 in the the host controller, but then again,
> > the libertas driver and/or the firmware doesn't like that and dies in
> > if_sdio_pro_real() with
> >
> > firmware wants 17 bytes
> > firmware helper signalled error
> >
> > Any idea how to get that working with only single block small transfers?
>
> All the Marvell documentation (v5 at least) refers to 512-byte transfers
> of the second-stage firmware in 32-byte blocks:
>
> Section 2.2.1.1 of the v5 spec states:
>
> "
> 2) If the length requested by helper is larger than 512 bytes, it is cut
> into multiple pieces for CMD53 write. The current download length is set
> to 512 bytes (16 blocks x 32 bytes per block) in each iteration of CMD53
> write.
> 3) Host starts the download of 16 blocks of firmware (512 bytes)
> 4) Host copies the payload to the buffer.
> 5) Host writes 16 blocks of the firmware image data using CMD 53.
> 6) Repeat Steps 3 through 5 until the firmware image data specified by
> the helper (Step 2) for this iteration is downloaded completely.
> "
>
> The helper firmware may well expect all 16 blocks. But try adjusting
> "chunk_size" in if_sdio.c::if_sdio_prog_real() down to one block (ie, 32
> not 512) and see if the helper pukes. The code looks like it can handle
> chunk_size changes just fine.
The code can, yes. But it seems the helper can't. I think I tried this
earlier. Here's the output:
[ 5.620000] libertas_sdio mmc0:0001:1: firmware: requesting sd8686_helper.bin
[ 5.700000] libertas sdio: waiting for helper to boot...
[ 5.710000] libertas_sdio mmc0:0001:1: firmware: requesting sd8686.bin
[ 5.770000] libertas sdio: firmware wants 16 bytes
[ 5.780000] libertas sdio: sending 16 bytes (32 bytes) chunk
[ 5.790000] libertas sdio: firmware wants 512 bytes
[ 5.790000] libertas sdio: sending 32 bytes (32 bytes) chunk
[ 5.800000] libertas sdio: sending 32 bytes (32 bytes) chunk
[ 5.810000] libertas sdio: sending 32 bytes (32 bytes) chunk
[ 5.810000] libertas sdio: sending 32 bytes (32 bytes) chunk
[ 5.820000] libertas sdio: sending 32 bytes (32 bytes) chunk
[ 5.830000] libertas sdio: sending 32 bytes (32 bytes) chunk
[ 5.830000] libertas sdio: sending 32 bytes (32 bytes) chunk
[ 5.840000] libertas sdio: sending 32 bytes (32 bytes) chunk
[ 5.840000] libertas sdio: sending 32 bytes (32 bytes) chunk
[ 5.850000] libertas sdio: sending 32 bytes (32 bytes) chunk
[ 5.860000] libertas sdio: sending 32 bytes (32 bytes) chunk
[ 5.860000] libertas sdio: sending 32 bytes (32 bytes) chunk
[ 5.870000] libertas sdio: sending 32 bytes (32 bytes) chunk
[ 5.880000] libertas sdio: sending 32 bytes (32 bytes) chunk
[ 5.880000] libertas sdio: sending 32 bytes (32 bytes) chunk
[ 5.890000] libertas sdio: sending 32 bytes (32 bytes) chunk
[ 5.900000] libertas sdio: firmware wants 17 bytes
[ 5.900000] libertas sdio: firmware helper signalled error
[ 5.910000] libertas: failed to load firmware
[ 5.910000] libertas_sdio: probe of mmc0:0001:1 failed with error -5
Maybe I need to tweak the core to send 512 bytes in one block instead of
multiple ones?
Just to exclude other issues - seeing the driver coming that far tells
that electrical issues can't be the reason, right? Or is there anything
else that changes after the helper is downloaded successfully? Does the
hardware change anything on the hardware link layer at this point?
Daniel
^ permalink raw reply [flat|nested] 14+ messages in thread
* MXC MMC driver and SDIO peripherals
2009-10-28 17:19 ` Daniel Mack
@ 2009-10-28 18:46 ` Dan Williams
0 siblings, 0 replies; 14+ messages in thread
From: Dan Williams @ 2009-10-28 18:46 UTC (permalink / raw)
To: linux-arm-kernel
On Wed, 2009-10-28 at 18:19 +0100, Daniel Mack wrote:
> On Wed, Oct 28, 2009 at 10:06:02AM -0700, Dan Williams wrote:
> > On Wed, 2009-10-28 at 17:47 +0100, Daniel Mack wrote:
> > > I did some more research on this and it turns out that the problem is
> > > related to multi block transfers. At least, this is when it first
> > > occurs.
> > >
> > > The libertas SDIO driver downloads two firmwares to the device, one
> > > 'helper' and one 'real' firmware The first one only uses chunks of 64
> > > bytes each and that seems to work fine. The real firmware, however,
> > > loads in 512 bytes chunks which the SDIO core breaks up into 16 blocks
> > > of 32 bytes. And this is where the MXC host controller bails out with a
> > > CRC error. Unfortunately, it does not give any more detailed information
> > > about what exactly went wrong.
> > >
> > > The effect might be related to an errata entry[1], which is what I'm
> > > currently investigating. To do so, I would like to limit the the
> > > communication to singe-block transfers, just to exclude all other
> > > possible (electrical, clock speed, ...) issues. I did that by setting
> > > mmc->max_blk_count to 1 in the the host controller, but then again,
> > > the libertas driver and/or the firmware doesn't like that and dies in
> > > if_sdio_pro_real() with
> > >
> > > firmware wants 17 bytes
> > > firmware helper signalled error
> > >
> > > Any idea how to get that working with only single block small transfers?
> >
> > All the Marvell documentation (v5 at least) refers to 512-byte transfers
> > of the second-stage firmware in 32-byte blocks:
> >
> > Section 2.2.1.1 of the v5 spec states:
> >
> > "
> > 2) If the length requested by helper is larger than 512 bytes, it is cut
> > into multiple pieces for CMD53 write. The current download length is set
> > to 512 bytes (16 blocks x 32 bytes per block) in each iteration of CMD53
> > write.
> > 3) Host starts the download of 16 blocks of firmware (512 bytes)
> > 4) Host copies the payload to the buffer.
> > 5) Host writes 16 blocks of the firmware image data using CMD 53.
> > 6) Repeat Steps 3 through 5 until the firmware image data specified by
> > the helper (Step 2) for this iteration is downloaded completely.
> > "
> >
> > The helper firmware may well expect all 16 blocks. But try adjusting
> > "chunk_size" in if_sdio.c::if_sdio_prog_real() down to one block (ie, 32
> > not 512) and see if the helper pukes. The code looks like it can handle
> > chunk_size changes just fine.
>
> The code can, yes. But it seems the helper can't. I think I tried this
> earlier. Here's the output:
>
> [ 5.620000] libertas_sdio mmc0:0001:1: firmware: requesting sd8686_helper.bin
> [ 5.700000] libertas sdio: waiting for helper to boot...
> [ 5.710000] libertas_sdio mmc0:0001:1: firmware: requesting sd8686.bin
> [ 5.770000] libertas sdio: firmware wants 16 bytes
> [ 5.780000] libertas sdio: sending 16 bytes (32 bytes) chunk
> [ 5.790000] libertas sdio: firmware wants 512 bytes
> [ 5.790000] libertas sdio: sending 32 bytes (32 bytes) chunk
> [ 5.800000] libertas sdio: sending 32 bytes (32 bytes) chunk
> [ 5.810000] libertas sdio: sending 32 bytes (32 bytes) chunk
> [ 5.810000] libertas sdio: sending 32 bytes (32 bytes) chunk
> [ 5.820000] libertas sdio: sending 32 bytes (32 bytes) chunk
> [ 5.830000] libertas sdio: sending 32 bytes (32 bytes) chunk
> [ 5.830000] libertas sdio: sending 32 bytes (32 bytes) chunk
> [ 5.840000] libertas sdio: sending 32 bytes (32 bytes) chunk
> [ 5.840000] libertas sdio: sending 32 bytes (32 bytes) chunk
> [ 5.850000] libertas sdio: sending 32 bytes (32 bytes) chunk
> [ 5.860000] libertas sdio: sending 32 bytes (32 bytes) chunk
> [ 5.860000] libertas sdio: sending 32 bytes (32 bytes) chunk
> [ 5.870000] libertas sdio: sending 32 bytes (32 bytes) chunk
> [ 5.880000] libertas sdio: sending 32 bytes (32 bytes) chunk
> [ 5.880000] libertas sdio: sending 32 bytes (32 bytes) chunk
> [ 5.890000] libertas sdio: sending 32 bytes (32 bytes) chunk
> [ 5.900000] libertas sdio: firmware wants 17 bytes
> [ 5.900000] libertas sdio: firmware helper signalled error
> [ 5.910000] libertas: failed to load firmware
> [ 5.910000] libertas_sdio: probe of mmc0:0001:1 failed with error -5
>
> Maybe I need to tweak the core to send 512 bytes in one block instead of
> multiple ones?
Maybe? But I bet the helper would fail on that too, since it's
expecting 32 byte blocks.
> Just to exclude other issues - seeing the driver coming that far tells
> that electrical issues can't be the reason, right? Or is there anything
> else that changes after the helper is downloaded successfully? Does the
> hardware change anything on the hardware link layer at this point?
I can't think of a reason why it would be electrical, but we can't
exclude that completely of course. The helper is simply a small program
that knows how to buffer a larger firmware and load that firmware at a
given address in memory on the Libertas. I don't believe it has
anything to do with the SDIO bits of the chip, but I don't know for sure
since I don't have the code for it.
I think this just boils down to a pretty badly implemented SDHC :(
Dan
^ permalink raw reply [flat|nested] 14+ messages in thread
* MXC MMC driver and SDIO peripherals
2009-10-28 17:06 ` Dan Williams
2009-10-28 17:19 ` Daniel Mack
@ 2009-10-29 10:27 ` Daniel Mack
2009-11-02 20:00 ` Dan Williams
1 sibling, 1 reply; 14+ messages in thread
From: Daniel Mack @ 2009-10-29 10:27 UTC (permalink / raw)
To: linux-arm-kernel
On Wed, Oct 28, 2009 at 10:06:02AM -0700, Dan Williams wrote:
> On Wed, 2009-10-28 at 17:47 +0100, Daniel Mack wrote:
> > I did some more research on this and it turns out that the problem is
> > related to multi block transfers. At least, this is when it first
> > occurs.
> >
> > The libertas SDIO driver downloads two firmwares to the device, one
> > 'helper' and one 'real' firmware The first one only uses chunks of 64
> > bytes each and that seems to work fine. The real firmware, however,
> > loads in 512 bytes chunks which the SDIO core breaks up into 16 blocks
> > of 32 bytes. And this is where the MXC host controller bails out with a
> > CRC error. Unfortunately, it does not give any more detailed information
> > about what exactly went wrong.
> >
> > The effect might be related to an errata entry[1], which is what I'm
> > currently investigating. To do so, I would like to limit the the
> > communication to singe-block transfers, just to exclude all other
> > possible (electrical, clock speed, ...) issues. I did that by setting
> > mmc->max_blk_count to 1 in the the host controller, but then again,
> > the libertas driver and/or the firmware doesn't like that and dies in
> > if_sdio_pro_real() with
> >
> > firmware wants 17 bytes
> > firmware helper signalled error
A number of bytes requested has bit 1 set indicates an error, according
to the code if_sdio_prog_real(). Is there any more information in such
cases? An error code that tells us about the real reason maybe?
> All the Marvell documentation (v5 at least) refers to 512-byte transfers
> of the second-stage firmware in 32-byte blocks:
>
> Section 2.2.1.1 of the v5 spec states:
What documentation is that? Is it publically available?
Thanks,
Daniel
^ permalink raw reply [flat|nested] 14+ messages in thread
* MXC MMC driver and SDIO peripherals
2009-10-29 10:27 ` Daniel Mack
@ 2009-11-02 20:00 ` Dan Williams
0 siblings, 0 replies; 14+ messages in thread
From: Dan Williams @ 2009-11-02 20:00 UTC (permalink / raw)
To: linux-arm-kernel
On Thu, 2009-10-29 at 11:27 +0100, Daniel Mack wrote:
> On Wed, Oct 28, 2009 at 10:06:02AM -0700, Dan Williams wrote:
> > On Wed, 2009-10-28 at 17:47 +0100, Daniel Mack wrote:
> > > I did some more research on this and it turns out that the problem is
> > > related to multi block transfers. At least, this is when it first
> > > occurs.
> > >
> > > The libertas SDIO driver downloads two firmwares to the device, one
> > > 'helper' and one 'real' firmware The first one only uses chunks of 64
> > > bytes each and that seems to work fine. The real firmware, however,
> > > loads in 512 bytes chunks which the SDIO core breaks up into 16 blocks
> > > of 32 bytes. And this is where the MXC host controller bails out with a
> > > CRC error. Unfortunately, it does not give any more detailed information
> > > about what exactly went wrong.
> > >
> > > The effect might be related to an errata entry[1], which is what I'm
> > > currently investigating. To do so, I would like to limit the the
> > > communication to singe-block transfers, just to exclude all other
> > > possible (electrical, clock speed, ...) issues. I did that by setting
> > > mmc->max_blk_count to 1 in the the host controller, but then again,
> > > the libertas driver and/or the firmware doesn't like that and dies in
> > > if_sdio_pro_real() with
> > >
> > > firmware wants 17 bytes
> > > firmware helper signalled error
>
> A number of bytes requested has bit 1 set indicates an error, according
> to the code if_sdio_prog_real(). Is there any more information in such
> cases? An error code that tells us about the real reason maybe?
Not that I know of; the helper is pretty simple. The v9 SD8686 vendor
driver assumes that any helper error is a CRC error, and retries that
block a few times before failing. But the helper asking for 17 bytes
seems a bit suspicious. Are you sure there aren't any TX/RX issues with
your SDHC and the connections to the card?
> > All the Marvell documentation (v5 at least) refers to 512-byte transfers
> > of the second-stage firmware in 32-byte blocks:
> >
> > Section 2.2.1.1 of the v5 spec states:
>
> What documentation is that? Is it publically available?
http://wiki.laptop.org/images/f/f3/Firmware-Spec-v5.1-MV-S103752-00.pdf
Dan
^ permalink raw reply [flat|nested] 14+ messages in thread
* MXC MMC driver and SDIO peripherals
2009-10-28 16:47 ` Daniel Mack
2009-10-28 17:06 ` Dan Williams
@ 2009-10-28 17:11 ` Dan Williams
2009-10-28 17:21 ` Daniel Mack
1 sibling, 1 reply; 14+ messages in thread
From: Dan Williams @ 2009-10-28 17:11 UTC (permalink / raw)
To: linux-arm-kernel
On Wed, 2009-10-28 at 17:47 +0100, Daniel Mack wrote:
> On Wed, Oct 21, 2009 at 01:15:19PM -0700, Dan Williams wrote:
> > On Wed, 2009-10-21 at 21:20 +0200, Daniel Mack wrote:
> > > Hi,
> > >
> > > we're having trouble getting SDIO connected harware to fly on MX31 based
> > > designs. In particular, a SD8686 chip supported by the libertas_sdio
> > > driver will hang forever when built without CONFIG_MMC_DEBUG=y. With
> > > that option selected, however, the behaviour is a little different, and
> > > I can at least see the following messages on a recent 2.6.32-rc5 based
> > > MX31 tree.
> > >
> > > Is there any common pitfall for such setups? I did more or less the same
> > > thing on PXAs (same WLAN chip, same kind of interface, same firmware),
> > > and haven't seen any such effects, so I suspect the MXC specific parts
> > > to be the reason for that. Any ideas?
> >
> > Any idea what quirks your SDHC is using if any? Does it require PIO or
> > can it do DMA? Does it have any transfer restrictions on block size or
> > bit-width? What is the debug output of the MMC stack when loading the
> > module for your SDHC?
>
> I did some more research on this and it turns out that the problem is
> related to multi block transfers. At least, this is when it first
> occurs.
>
> The libertas SDIO driver downloads two firmwares to the device, one
> 'helper' and one 'real' firmware The first one only uses chunks of 64
> bytes each and that seems to work fine. The real firmware, however,
> loads in 512 bytes chunks which the SDIO core breaks up into 16 blocks
> of 32 bytes. And this is where the MXC host controller bails out with a
> CRC error. Unfortunately, it does not give any more detailed information
> about what exactly went wrong.
>
> The effect might be related to an errata entry[1], which is what I'm
> currently investigating. To do so, I would like to limit the the
> communication to singe-block transfers, just to exclude all other
> possible (electrical, clock speed, ...) issues. I did that by setting
> mmc->max_blk_count to 1 in the the host controller, but then again,
> the libertas driver and/or the firmware doesn't like that and dies in
> if_sdio_pro_real() with
>
> firmware wants 17 bytes
> firmware helper signalled error
>
> Any idea how to get that working with only single block small transfers?
Just a note; single-block transfers will probably kill your wifi
performance, especially if the errata are true. When the libertas
driver sends network data packets it sends them with
ret = sdio_writesb(card->func, card->ioport,
packet->buffer, packet->nb);
so if your packet is normal ethernet 1500 bytes, breaking that up in to
47 single block transfers of 32-bytes each is going to be slow...
Dan
> Btw - there's a number of things missing for SDIO in the MXC MMC driver
> which I implemented/fixed. I'll send patches as soon as I have more
> confidence about the whole setup.
>
>
> Thanks,
> Daniel
>
>
> [1] Errata IDs TLSbo91748 and TLSbo78667 from
> http://www.freescale.com/files/32bit/doc/errata/MCIMX31CE.pdf?fpsp=1
>
>
> _______________________________________________
> libertas-dev mailing list
> libertas-dev at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/libertas-dev
^ permalink raw reply [flat|nested] 14+ messages in thread
* MXC MMC driver and SDIO peripherals
2009-10-28 17:11 ` Dan Williams
@ 2009-10-28 17:21 ` Daniel Mack
0 siblings, 0 replies; 14+ messages in thread
From: Daniel Mack @ 2009-10-28 17:21 UTC (permalink / raw)
To: linux-arm-kernel
On Wed, Oct 28, 2009 at 10:11:04AM -0700, Dan Williams wrote:
> On Wed, 2009-10-28 at 17:47 +0100, Daniel Mack wrote:
> > I did some more research on this and it turns out that the problem is
> > related to multi block transfers. At least, this is when it first
> > occurs.
> >
> > The libertas SDIO driver downloads two firmwares to the device, one
> > 'helper' and one 'real' firmware The first one only uses chunks of 64
> > bytes each and that seems to work fine. The real firmware, however,
> > loads in 512 bytes chunks which the SDIO core breaks up into 16 blocks
> > of 32 bytes. And this is where the MXC host controller bails out with a
> > CRC error. Unfortunately, it does not give any more detailed information
> > about what exactly went wrong.
> >
> > The effect might be related to an errata entry[1], which is what I'm
> > currently investigating. To do so, I would like to limit the the
> > communication to singe-block transfers, just to exclude all other
> > possible (electrical, clock speed, ...) issues. I did that by setting
> > mmc->max_blk_count to 1 in the the host controller, but then again,
> > the libertas driver and/or the firmware doesn't like that and dies in
> > if_sdio_pro_real() with
> >
> > firmware wants 17 bytes
> > firmware helper signalled error
> >
> > Any idea how to get that working with only single block small transfers?
>
> Just a note; single-block transfers will probably kill your wifi
> performance, especially if the errata are true. When the libertas
> driver sends network data packets it sends them with
>
> ret = sdio_writesb(card->func, card->ioport,
> packet->buffer, packet->nb);
>
> so if your packet is normal ethernet 1500 bytes, breaking that up in to
> 47 single block transfers of 32-bytes each is going to be slow...
Yep, I know. Thats's a disaster, especially without DMA enabled (which
is currently the case).
But I'd like to see it working somehow first and then see whether that's
really the issue :)
Daniel
^ permalink raw reply [flat|nested] 14+ messages in thread