On Thu, Jun 6, 2024 at 12:00 PM Andrew.Yuan <andrew.y...@jaguarmicro.com> wrote:
> In the Cadence IP for Gigabit Ethernet MAC Part Number: IP7014 IP > Rev: R1p12 - Doc Rev: 1.3 User Guide, the specification for the > type2_compare_x_word_0 register is as follows: > The byte stored in bits [23:16] is compared against the byte in > the received frame from the selected offset+0, and the byte stored in bits > [31:24] is compared against the byte in > the received frame from the selected offset+1. > > However, there is an implementation error in the cadence_gem model > in qemu： > the byte stored in bits [31:24] is compared against the byte in > the received frame from the selected offset+0 > > Now, the error code is as follows: > rx_cmp = rxbuf_ptr[offset] << 8 | rxbuf_ptr[offset]; > > and needs to be corrected to： > rx_cmp = rxbuf_ptr[offset + 1] << 8 | rxbuf_ptr[offset]; > > Signed-off-by: Andrew.Yuan <andrew.y...@jaguarmicro.com> > LGTM: Reviewed-by: Edgar E. Iglesias <edgar.igles...@amd.com> At some point it would be nice to add the missing logic for the DISABLE_MASK bit that extends the compare range from 16 to 32-bits. Cheers, Edgar > --- > hw/net/cadence_gem.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/hw/net/cadence_gem.c b/hw/net/cadence_gem.c > index ec7bf562e5..9c73ded0d3 100644 > --- a/hw/net/cadence_gem.c > +++ b/hw/net/cadence_gem.c > @@ -946,7 +946,7 @@ static int get_queue_from_screen(CadenceGEMState *s, > uint8_t *rxbuf_ptr, > break; > } > > - rx_cmp = rxbuf_ptr[offset] << 8 | rxbuf_ptr[offset]; > + rx_cmp = rxbuf_ptr[offset + 1] << 8 | rxbuf_ptr[offset]; > mask = FIELD_EX32(cr0, TYPE2_COMPARE_0_WORD_0, MASK_VALUE); > compare = FIELD_EX32(cr0, TYPE2_COMPARE_0_WORD_0, > COMPARE_VALUE); > > -- > 2.37.0.windows.1 > >
