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[PATCH v2 0/3] hw/i3c: fix DW-I3C FIFO depth advertisement

Jithu Joseph posted 3 patches 3 days, 21 hours ago
Patches applied successfully (tree, apply log)
git fetch https://github.com/patchew-project/qemu tags/patchew/20260604000734.1094382-1-jithu.joseph@oss.qualcomm.com
Maintainers: Joe Komlodi <komlodi@google.com>, "Cédric Le Goater" <clg@kaod.org>, Jamin Lin <jamin_lin@aspeedtech.com>, Nabih Estefan <nabihestefan@google.com>
There is a newer version of this series
include/hw/i3c/dw-i3c.h |  6 ++---
hw/i3c/dw-i3c.c         | 58 +++++++++++++++++++++++++++++++----------
2 files changed, 47 insertions(+), 17 deletions(-)
[PATCH v2 0/3] hw/i3c: fix DW-I3C FIFO depth advertisement
Posted by Jithu Joseph 3 days, 21 hours ago 
This series corrects the DesignWare I3C controller's advertised CMD/data
FIFO depths and cleans up the misleading queue-capacity field names that
made the bug easy to overlook.

The Linux DW-I3C master driver reads QUEUE_STATUS_LEVEL and
DATA_BUFFER_STATUS_LEVEL at probe to learn the controller's queue depths,
then rejects any transfer larger than what was advertised with
-EOPNOTSUPP.  QEMU was resetting these registers to 0x02 / 0x10 instead of
the real 0x10 / 0x40, so the guest believed the controller could only do
64-byte transfers and failed any I3C transfer with a payload larger than
64 B.  The backing FIFOs were already allocated at the correct size; only
the advertised reset values were wrong.

Patch 1 fixes the reset values, and additionally drives the advertised
depths from the queue-capacity configs in the reset handlers (per
Philippe's review) so a configured override is no longer silently ignored.
Patch 2 is a no-functional-change cleanup renaming the queue-capacity
struct fields and device properties from _bytes to _words, since the
values are word counts passed to fifo32_create() -- the old names were
what made the depth bug slow to spot.  Patch 3 keeps the old _bytes
property names working as aliases, since they are user-visible and shipped
in v11.0.0.

Patch 1 is the actual bug fix and is tagged Cc: qemu-stable; it is kept
self-contained (using the _bytes field names that exist in released
branches) so it cherry-picks cleanly.  Patches 2 and 3 are master-only
cleanup.

Note on the IBI queue capacity: unlike the cmd/resp and tx/rx capacities,
it is not advertised to the guest through any status register (the
hardware exposes only IBI occupancy via IBI_BUF_BLR / IBI_STATUS_CNT, not
a depth), so it sizes only the internal fifo32 backing store and has no
entry in dw_i3c_resets[].

Changes since v1:
 - Patch 1: drive QUEUE_STATUS_LEVEL / DATA_BUFFER_STATUS_LEVEL from the
   queue-capacity configs in the reset handlers, in addition to correcting
   the reset-array values (Philippe Mathieu-Daude).
 - New patch 3: keep the renamed _bytes properties working as aliases so
   existing command lines do not break (Philippe Mathieu-Daude).
 - v1: https://lore.kernel.org/qemu-devel/20260529014034.864722-1-jithu.joseph@oss.qualcomm.com/

Jithu Joseph (3):
  hw/i3c: fix CMD/data FIFO depth reset values to match real silicon
  hw/i3c: rename DW-I3C queue capacity fields from _bytes to _words
  hw/i3c: keep _bytes aliases for renamed queue-capacity properties

 include/hw/i3c/dw-i3c.h |  6 ++---
 hw/i3c/dw-i3c.c         | 58 +++++++++++++++++++++++++++++++----------
 2 files changed, 47 insertions(+), 17 deletions(-)


base-commit: 2db91528542672cf0db78b3f2cc0e22b36302b38
-- 
2.43.0
Re: [PATCH v2 0/3] hw/i3c: fix DW-I3C FIFO depth advertisement
Posted by Cédric Le Goater 3 days, 12 hours ago 
On 6/4/26 02:07, Jithu Joseph wrote:
> This series corrects the DesignWare I3C controller's advertised CMD/data
> FIFO depths and cleans up the misleading queue-capacity field names that
> made the bug easy to overlook.
> 
> The Linux DW-I3C master driver reads QUEUE_STATUS_LEVEL and
> DATA_BUFFER_STATUS_LEVEL at probe to learn the controller's queue depths,
> then rejects any transfer larger than what was advertised with
> -EOPNOTSUPP.  QEMU was resetting these registers to 0x02 / 0x10 instead of
> the real 0x10 / 0x40, so the guest believed the controller could only do
> 64-byte transfers and failed any I3C transfer with a payload larger than
> 64 B.  The backing FIFOs were already allocated at the correct size; only
> the advertised reset values were wrong.
> 
> Patch 1 fixes the reset values, and additionally drives the advertised
> depths from the queue-capacity configs in the reset handlers (per
> Philippe's review) so a configured override is no longer silently ignored.
> Patch 2 is a no-functional-change cleanup renaming the queue-capacity
> struct fields and device properties from _bytes to _words, since the
> values are word counts passed to fifo32_create() -- the old names were
> what made the depth bug slow to spot.  Patch 3 keeps the old _bytes
> property names working as aliases, since they are user-visible and shipped
> in v11.0.0.
> 
> Patch 1 is the actual bug fix and is tagged Cc: qemu-stable; it is kept
> self-contained (using the _bytes field names that exist in released
> branches) so it cherry-picks cleanly.  Patches 2 and 3 are master-only
> cleanup.
> 
> Note on the IBI queue capacity: unlike the cmd/resp and tx/rx capacities,
> it is not advertised to the guest through any status register (the
> hardware exposes only IBI occupancy via IBI_BUF_BLR / IBI_STATUS_CNT, not
> a depth), so it sizes only the internal fifo32 backing store and has no
> entry in dw_i3c_resets[].
> 
> Changes since v1:
>   - Patch 1: drive QUEUE_STATUS_LEVEL / DATA_BUFFER_STATUS_LEVEL from the
>     queue-capacity configs in the reset handlers, in addition to correcting
>     the reset-array values (Philippe Mathieu-Daude).
>   - New patch 3: keep the renamed _bytes properties working as aliases so
>     existing command lines do not break (Philippe Mathieu-Daude).
>   - v1: https://lore.kernel.org/qemu-devel/20260529014034.864722-1-jithu.joseph@oss.qualcomm.com/
> 
> Jithu Joseph (3):
>    hw/i3c: fix CMD/data FIFO depth reset values to match real silicon
>    hw/i3c: rename DW-I3C queue capacity fields from _bytes to _words
>    hw/i3c: keep _bytes aliases for renamed queue-capacity properties
> 
>   include/hw/i3c/dw-i3c.h |  6 ++---
>   hw/i3c/dw-i3c.c         | 58 +++++++++++++++++++++++++++++++----------
>   2 files changed, 47 insertions(+), 17 deletions(-)
> 
> 
> base-commit: 2db91528542672cf0db78b3f2cc0e22b36302b38


Jithu,

When you sent this v2, you did as a thread reply to :

   https://lore.kernel.org/qemu-devel/20260529014034.864722-1-jithu.joseph@oss.qualcomm.com/	

This confuses the b4 tool and, in consequence, Jamin's Reviewed-by
is not collected it seems.

Can you please resend as new thread ? If you can can collect Jamin's
Reviewed-by trailers it would be nice.

Thanks,

C.
Re: [PATCH v2 0/3] hw/i3c: fix DW-I3C FIFO depth advertisement
Posted by Jithu Joseph 3 days, 5 hours ago 
On 6/4/2026 1:28 AM, Cédric Le Goater wrote:
> On 6/4/26 02:07, Jithu Joseph wrote:
>> This series corrects the DesignWare I3C controller's advertised CMD/data
>> FIFO depths and cleans up the misleading queue-capacity field names that
>> made the bug easy to overlook.
>>

...
> 
> 
> Jithu,
> 
> When you sent this v2, you did as a thread reply to :
> 
>   https://lore.kernel.org/qemu-devel/20260529014034.864722-1-jithu.joseph@oss.qualcomm.com/   
> 
> This confuses the b4 tool and, in consequence, Jamin's Reviewed-by
> is not collected it seems.

Sorry Cédric that it broke your MAINTAINER flow ... 
(I used to follow similar threading while sending newer revisions in LKML a while back) 

> 
> Can you please resend as new thread ? If you can can collect Jamin's
> Reviewed-by trailers it would be nice.

I just sent out v3 with Jaimin's tag here
https://lore.kernel.org/qemu-devel/20260604142207.2118098-1-jithu.joseph@oss.qualcomm.com/

Thanks
Jithu
Re: [PATCH v2 0/3] hw/i3c: fix DW-I3C FIFO depth advertisement
Posted by Cédric Le Goater 3 days, 5 hours ago 
On 6/4/26 17:24, Jithu Joseph wrote:
> On 6/4/2026 1:28 AM, Cédric Le Goater wrote:
>> On 6/4/26 02:07, Jithu Joseph wrote:
>>> This series corrects the DesignWare I3C controller's advertised CMD/data
>>> FIFO depths and cleans up the misleading queue-capacity field names that
>>> made the bug easy to overlook.
>>>
> 
> ...
>>
>>
>> Jithu,
>>
>> When you sent this v2, you did as a thread reply to :
>>
>>    https://lore.kernel.org/qemu-devel/20260529014034.864722-1-jithu.joseph@oss.qualcomm.com/
>>
>> This confuses the b4 tool and, in consequence, Jamin's Reviewed-by
>> is not collected it seems.
> 
> Sorry Cédric that it broke your MAINTAINER flow ...

Well b4 isn't smart enough to grab the trailers on v2. Try it.

> (I used to follow similar threading while sending newer revisions in LKML a while back)

I would recommend  to start a new email thread for each respin else
the newer version of a series is "hidden" under the previous thread.

>>
>> Can you please resend as new thread ? If you can can collect Jamin's
>> Reviewed-by trailers it would be nice.
> 
> I just sent out v3 with Jaimin's tag here
> https://lore.kernel.org/qemu-devel/20260604142207.2118098-1-jithu.joseph@oss.qualcomm.com/


Applied to

     https://github.com/legoater/qemu aspeed-next

Thanks,

C.
Re: [PATCH v2 0/3] hw/i3c: fix DW-I3C FIFO depth advertisement
Posted by Jithu Joseph 3 days, 5 hours ago 
On 6/4/2026 8:33 AM, Cédric Le Goater wrote:
> On 6/4/26 17:24, Jithu Joseph wrote:
>> On 6/4/2026 1:28 AM, Cédric Le Goater wrote:
>>> On 6/4/26 02:07, Jithu Joseph wrote:
>>>> This series corrects the DesignWare I3C controller's advertised CMD/data
>>>> FIFO depths and cleans up the misleading queue-capacity field names that
>>>> made the bug easy to overlook.
>>>>
>>
>> ...
>>>
>>>
>>> Jithu,
>>>
>>> When you sent this v2, you did as a thread reply to :
>>>
>>>    https://lore.kernel.org/qemu-devel/20260529014034.864722-1-jithu.joseph@oss.qualcomm.com/
>>>
>>> This confuses the b4 tool and, in consequence, Jamin's Reviewed-by
>>> is not collected it seems.
>>
>> Sorry Cédric that it broke your MAINTAINER flow ...
> 
> Well b4 isn't smart enough to grab the trailers on v2. Try it.
>

Yes I tried it, and I could see that b4 didn't pick the tags
 

>> (I used to follow similar threading while sending newer revisions in LKML a while back)
> 
> I would recommend  to start a new email thread for each respin else
> the newer version of a series is "hidden" under the previous thread.
> 

Noted will follow this for future patches

>>>
>>> Can you please resend as new thread ? If you can can collect Jamin's
>>> Reviewed-by trailers it would be nice.
>>
>> I just sent out v3 with Jaimin's tag here
>> https://lore.kernel.org/qemu-devel/20260604142207.2118098-1-jithu.joseph@oss.qualcomm.com/
> 
> 
> Applied to
> 
>     https://github.com/legoater/qemu aspeed-next

Thanks

Jithu
RE: [PATCH v2 0/3] hw/i3c: fix DW-I3C FIFO depth advertisement
Posted by Jamin Lin 3 days, 20 hours ago 
Hi Jithu,

> -----Original Message-----
> From: Jithu Joseph <jithu.joseph@oss.qualcomm.com>
> Sent: Thursday, June 4, 2026 8:08 AM
> To: clg@kaod.org; Jamin Lin <jamin_lin@aspeedtech.com>;
> komlodi@google.com
> Cc: nabihestefan@google.com; philmd@linaro.org;
> jithu.joseph@oss.qualcomm.com; qemu-devel@nongnu.org
> Subject: [PATCH v2 0/3] hw/i3c: fix DW-I3C FIFO depth advertisement
> 
> This series corrects the DesignWare I3C controller's advertised CMD/data FIFO
> depths and cleans up the misleading queue-capacity field names that made
> the bug easy to overlook.
> 
> The Linux DW-I3C master driver reads QUEUE_STATUS_LEVEL and
> DATA_BUFFER_STATUS_LEVEL at probe to learn the controller's queue depths,
> then rejects any transfer larger than what was advertised with -EOPNOTSUPP.
> QEMU was resetting these registers to 0x02 / 0x10 instead of the real 0x10 /
> 0x40, so the guest believed the controller could only do 64-byte transfers and
> failed any I3C transfer with a payload larger than
> 64 B.  The backing FIFOs were already allocated at the correct size; only the
> advertised reset values were wrong.
> 
> Patch 1 fixes the reset values, and additionally drives the advertised depths
> from the queue-capacity configs in the reset handlers (per Philippe's review) so
> a configured override is no longer silently ignored.
> Patch 2 is a no-functional-change cleanup renaming the queue-capacity struct
> fields and device properties from _bytes to _words, since the values are word
> counts passed to fifo32_create() -- the old names were what made the depth
> bug slow to spot.  Patch 3 keeps the old _bytes property names working as
> aliases, since they are user-visible and shipped in v11.0.0.
> 
> Patch 1 is the actual bug fix and is tagged Cc: qemu-stable; it is kept
> self-contained (using the _bytes field names that exist in released
> branches) so it cherry-picks cleanly.  Patches 2 and 3 are master-only
> cleanup.
> 
> Note on the IBI queue capacity: unlike the cmd/resp and tx/rx capacities, it is
> not advertised to the guest through any status register (the hardware exposes
> only IBI occupancy via IBI_BUF_BLR / IBI_STATUS_CNT, not a depth), so it sizes
> only the internal fifo32 backing store and has no entry in dw_i3c_resets[].
> 
> Changes since v1:
>  - Patch 1: drive QUEUE_STATUS_LEVEL / DATA_BUFFER_STATUS_LEVEL from
> the
>    queue-capacity configs in the reset handlers, in addition to correcting
>    the reset-array values (Philippe Mathieu-Daude).
>  - New patch 3: keep the renamed _bytes properties working as aliases so
>    existing command lines do not break (Philippe Mathieu-Daude).
>  - v1:
> https://lore.kernel.org/qemu-devel/20260529014034.864722-1-jithu.joseph@o
> ss.qualcomm.com/
> 
> Jithu Joseph (3):
>   hw/i3c: fix CMD/data FIFO depth reset values to match real silicon
>   hw/i3c: rename DW-I3C queue capacity fields from _bytes to _words
>   hw/i3c: keep _bytes aliases for renamed queue-capacity properties
> 
>  include/hw/i3c/dw-i3c.h |  6 ++---
>  hw/i3c/dw-i3c.c         | 58 +++++++++++++++++++++++++++++++----------
>  2 files changed, 47 insertions(+), 17 deletions(-)
> 
> 
> base-commit: 2db91528542672cf0db78b3f2cc0e22b36302b38
> --
> 2.43.0

This patch series:

Reviewed-by: Jamin Lin <jamin_lin@aspeedtech.com>

Thanks,
Jamin

Patchew 2.1-devel-ea86937

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