- EFX_POPULATE_OWORD_3(oword,
- ERF_DZ_TX_DESC_WPTR, wptr,
- ERF_DZ_TX_DESC_HWORD, EFX_QWORD_FIELD(desc, EFX_DWORD_1),
- ERF_DZ_TX_DESC_LWORD, EFX_QWORD_FIELD(desc, EFX_DWORD_0));
-
- /* Guarantee ordering of memory (descriptors) and PIO (doorbell) */
- EFX_DMA_SYNC_QUEUE_FOR_DEVICE(etp->et_esmp, etp->et_mask + 1, wptr, id);
- EFSYS_PIO_WRITE_BARRIER();
- EFX_BAR_TBL_DOORBELL_WRITEO(enp, ER_DZ_TX_DESC_UPD_REG, etp->et_index,
- &oword);
+
+ /*
+ * Bug 65776: TSO option descriptors cannot be pushed if pacer bypass is
+ * enabled on the event queue this transmit queue is attached to.
+ *
+ * To ensure the code is safe, it is easiest to simply test the type of
+ * the descriptor to push, and only push it is if it not a TSO option
+ * descriptor.
+ */
+ if ((EFX_QWORD_FIELD(desc, ESF_DZ_TX_DESC_IS_OPT) != 1) ||
+ (EFX_QWORD_FIELD(desc, ESF_DZ_TX_OPTION_TYPE) !=
+ ESE_DZ_TX_OPTION_DESC_TSO)) {
+ /* Push the descriptor and update the wptr. */
+ EFX_POPULATE_OWORD_3(oword, ERF_DZ_TX_DESC_WPTR, wptr,
+ ERF_DZ_TX_DESC_HWORD, EFX_QWORD_FIELD(desc, EFX_DWORD_1),
+ ERF_DZ_TX_DESC_LWORD, EFX_QWORD_FIELD(desc, EFX_DWORD_0));
+
+ /* Ensure ordering of memory (descriptors) and PIO (doorbell) */
+ EFX_DMA_SYNC_QUEUE_FOR_DEVICE(etp->et_esmp, etp->et_mask + 1,
+ wptr, id);
+ EFSYS_PIO_WRITE_BARRIER();
+ EFX_BAR_VI_DOORBELL_WRITEO(enp, ER_DZ_TX_DESC_UPD_REG,
+ etp->et_index, &oword);
+ } else {
+ efx_dword_t dword;
+
+ /*
+ * Only update the wptr. This is signalled to the hardware by
+ * only writing one DWORD of the doorbell register.
+ */
+ EFX_POPULATE_OWORD_1(oword, ERF_DZ_TX_DESC_WPTR, wptr);
+ dword = oword.eo_dword[2];
+
+ /* Ensure ordering of memory (descriptors) and PIO (doorbell) */
+ EFX_DMA_SYNC_QUEUE_FOR_DEVICE(etp->et_esmp, etp->et_mask + 1,
+ wptr, id);
+ EFSYS_PIO_WRITE_BARRIER();
+ EFX_BAR_VI_WRITED2(enp, ER_DZ_TX_DESC_UPD_REG,
+ etp->et_index, &dword, B_FALSE);
+ }