Hi Cédric

> 
> Jamin,
> 
> Does that look good ?
> 
> Thanks,
> 

Looks good to me.
Added review tag

Thanks,
Jamin

> C.
> 
> On 5/5/26 15:40, Ashish Anand wrote:
> > The target_info union in dw_i3c_addr_assign_cmd() declares pid, bcr,
> > and dcr as separate union members, causing them to all alias b[0]
> > rather than their correct positions in the ENTDAA response buffer.
> > This results in dw_i3c_update_char_table() being called with BCR and
> > DCR both read from b[0] instead of b[6] and b[7] respectively,
> > corrupting the device characteristics table on every ENTDAA operation.
> > Fix by replacing the broken members with uint64_t d and extracting
> > fields per the I3C spec ENTDAA wire format.
> >
> > Additionally, dw_i3c_update_char_table() incorrectly splits PID across
> > LOC1 and LOC2 at bit 32. Per the Linux kernel HCI driver
> > (drivers/i3c/master/mipi-i3c-hci/dct_v1.c), the DCT layout requires
> > LOC1 to hold pid[47:16] and LOC2 to hold pid[15:0]. Fix the split
> > accordingly.
> >
> > Signed-off-by: Ashish Anand <[email protected]>
> > ---
> >
> > Changes from v1 :
> > 1. Replaced broken union members with uint64_t d, added wire format
> comment.
> > 2. Replaced loop with be64_to_cpu(target_info.d) >> 16.
> > 3. Fixed LOC1/LOC2 split at bit 16 in dw_i3c_update_char_table.
> > 4. Added comment to i3c.h clarifying how core.c transmits t->pid during
> ENTDAA.
> >
> > Link to v1 -
> > https://lore.kernel.org/qemu-devel/exdu52mug6fh3bwj7ofo3jlltyuwjfnddxo
> > bio4w3jhaq6uv7k@boxo3j5ocef2/T/#t
> >
> > This bug was discovered during end-to-end ENTDAA testing where BCR and
> > DCR values observed in the char table register did not match the
> > target's actual BCR and DCR values.
> >
> >   hw/i3c/dw-i3c.c      | 16 +++++++---------
> >   include/hw/i3c/i3c.h |  7 +++++++
> >   2 files changed, 14 insertions(+), 9 deletions(-)
> >
> > diff --git a/hw/i3c/dw-i3c.c b/hw/i3c/dw-i3c.c index
> > d87d42be89..17ff484c5d 100644
> > --- a/hw/i3c/dw-i3c.c
> > +++ b/hw/i3c/dw-i3c.c
> > @@ -1459,11 +1459,10 @@ static void dw_i3c_update_char_table(DWI3C
> *s, uint8_t offset, uint64_t pid,
> >
> P_DEV_CHAR_TABLE_START_ADDR) /
> >                                             sizeof(uint32_t)) +
> >                                             (offset *
> sizeof(uint32_t));
> > -    s->regs[dev_index] = pid & 0xffffffff;
> > -    pid >>= 32;
> > +    s->regs[dev_index] = (pid >> 16) & 0xffffffff;
> >       s->regs[dev_index + 1] = FIELD_DP32(s->regs[dev_index + 1],
> >
> DEVICE_CHARACTERISTIC_TABLE_LOC2,
> > -                                        MSB_PID, pid);
> > +                                        MSB_PID, pid & 0xffff);
> >       s->regs[dev_index + 2] = FIELD_DP32(s->regs[dev_index + 2],
> >
> DEVICE_CHARACTERISTIC_TABLE_LOC3, DCR,
> >                                           dcr); @@ -1507,10
> +1506,9 @@
> > static void dw_i3c_addr_assign_cmd(DWI3C *s, DWI3CAddrAssignCmd cmd)
> >       for (i = 0; i < cmd.dev_count; i++) {
> >           uint8_t addr = dw_i3c_target_addr(s, cmd.dev_index + i);
> >           union {
> > -            uint64_t pid:48;
> > -            uint8_t bcr;
> > -            uint8_t dcr;
> > +            uint64_t d;
> >               uint32_t w[2];
> > +            /* Per I3C spec: b[0]=PID MSB, b[5]=PID LSB, b[6]=BCR,
> > + b[7]=DCR */
> >               uint8_t b[8];
> >           } target_info;
> >
> > @@ -1544,9 +1542,9 @@ static void dw_i3c_addr_assign_cmd(DWI3C *s,
> DWI3CAddrAssignCmd cmd)
> >               err = DW_I3C_RESP_QUEUE_ERR_DAA_NACK;
> >               break;
> >           }
> > -        dw_i3c_update_char_table(s, cmd.dev_index + i,
> > -                                            target_info.pid,
> target_info.bcr,
> > -                                            target_info.dcr, addr);
> > +        uint64_t pid = be64_to_cpu(target_info.d) >> 16;
> > +        dw_i3c_update_char_table(s, cmd.dev_index + i, pid,
> target_info.b[6],
> > +                                 target_info.b[7], addr);
> >
> >           /* Push the PID, BCR, and DCR to the RX queue. */
> >           dw_i3c_push_rx(s, target_info.w[0]); diff --git
> > a/include/hw/i3c/i3c.h b/include/hw/i3c/i3c.h index
> > 6ba90793ad..dcf8d9b143 100644
> > --- a/include/hw/i3c/i3c.h
> > +++ b/include/hw/i3c/i3c.h
> > @@ -138,6 +138,13 @@ struct I3CTarget {
> >       uint8_t static_address;
> >       uint8_t dcr;
> >       uint8_t bcr;
> > +    /*
> > +     * Provisioned ID. Since core.c sends this LSB-first during ENTDAA
> > +     * via (pid >> (offset * 8)) & 0xff, targets must store it
> > +     * pre-reversed so that pid[47:40] goes on the wire first, as
> > +     * required by the I3C spec.
> > +     *  e.g. for a device with pid 0xAABBCCDDEEFF, store
> 0xFFEEDDCCBBAA.
> > +     */
> >       uint64_t pid;
> >
> >       /* CCC State tracking. */

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