mdiobus_free(felix->imdio);
}
+/* Extract shortest continuous gate open intervals in ns for each traffic class
+ * of a cyclic tc-taprio schedule. If a gate is always open, the duration is
+ * considered U64_MAX. If the gate is always closed, it is considered 0.
+ */
+static void vsc9959_tas_min_gate_lengths(struct tc_taprio_qopt_offload *taprio,
+ u64 min_gate_len[OCELOT_NUM_TC])
+{
+ struct tc_taprio_sched_entry *entry;
+ u64 gate_len[OCELOT_NUM_TC];
+ int tc, i, n;
+
+ /* Initialize arrays */
+ for (tc = 0; tc < OCELOT_NUM_TC; tc++) {
+ min_gate_len[tc] = U64_MAX;
+ gate_len[tc] = 0;
+ }
+
+ /* If we don't have taprio, consider all gates as permanently open */
+ if (!taprio)
+ return;
+
+ n = taprio->num_entries;
+
+ /* Walk through the gate list twice to determine the length
+ * of consecutively open gates for a traffic class, including
+ * open gates that wrap around. We are just interested in the
+ * minimum window size, and this doesn't change what the
+ * minimum is (if the gate never closes, min_gate_len will
+ * remain U64_MAX).
+ */
+ for (i = 0; i < 2 * n; i++) {
+ entry = &taprio->entries[i % n];
+
+ for (tc = 0; tc < OCELOT_NUM_TC; tc++) {
+ if (entry->gate_mask & BIT(tc)) {
+ gate_len[tc] += entry->interval;
+ } else {
+ /* Gate closes now, record a potential new
+ * minimum and reinitialize length
+ */
+ if (min_gate_len[tc] > gate_len[tc])
+ min_gate_len[tc] = gate_len[tc];
+ gate_len[tc] = 0;
+ }
+ }
+ }
+}
+
+/* Update QSYS_PORT_MAX_SDU to make sure the static guard bands added by the
+ * switch (see the ALWAYS_GUARD_BAND_SCH_Q comment) are correct at all MTU
+ * values (the default value is 1518). Also, for traffic class windows smaller
+ * than one MTU sized frame, update QSYS_QMAXSDU_CFG to enable oversized frame
+ * dropping, such that these won't hang the port, as they will never be sent.
+ */
+static void vsc9959_tas_guard_bands_update(struct ocelot *ocelot, int port)
+{
+ struct ocelot_port *ocelot_port = ocelot->ports[port];
+ u64 min_gate_len[OCELOT_NUM_TC];
+ int speed, picos_per_byte;
+ u64 needed_bit_time_ps;
+ u32 val, maxlen;
+ u8 tas_speed;
+ int tc;
+
+ lockdep_assert_held(&ocelot->tas_lock);
+
+ val = ocelot_read_rix(ocelot, QSYS_TAG_CONFIG, port);
+ tas_speed = QSYS_TAG_CONFIG_LINK_SPEED_X(val);
+
+ switch (tas_speed) {
+ case OCELOT_SPEED_10:
+ speed = SPEED_10;
+ break;
+ case OCELOT_SPEED_100:
+ speed = SPEED_100;
+ break;
+ case OCELOT_SPEED_1000:
+ speed = SPEED_1000;
+ break;
+ case OCELOT_SPEED_2500:
+ speed = SPEED_2500;
+ break;
+ default:
+ return;
+ }
+
+ picos_per_byte = (USEC_PER_SEC * 8) / speed;
+
+ val = ocelot_port_readl(ocelot_port, DEV_MAC_MAXLEN_CFG);
+ /* MAXLEN_CFG accounts automatically for VLAN. We need to include it
+ * manually in the bit time calculation, plus the preamble and SFD.
+ */
+ maxlen = val + 2 * VLAN_HLEN;
+ /* Consider the standard Ethernet overhead of 8 octets preamble+SFD,
+ * 4 octets FCS, 12 octets IFG.
+ */
+ needed_bit_time_ps = (maxlen + 24) * picos_per_byte;
+
+ dev_dbg(ocelot->dev,
+ "port %d: max frame size %d needs %llu ps at speed %d\n",
+ port, maxlen, needed_bit_time_ps, speed);
+
+ vsc9959_tas_min_gate_lengths(ocelot_port->taprio, min_gate_len);
+
+ for (tc = 0; tc < OCELOT_NUM_TC; tc++) {
+ u32 max_sdu;
+
+ if (min_gate_len[tc] == U64_MAX /* Gate always open */ ||
+ min_gate_len[tc] * 1000 > needed_bit_time_ps) {
+ /* Setting QMAXSDU_CFG to 0 disables oversized frame
+ * dropping.
+ */
+ max_sdu = 0;
+ dev_dbg(ocelot->dev,
+ "port %d tc %d min gate len %llu"
+ ", sending all frames\n",
+ port, tc, min_gate_len[tc]);
+ } else {
+ /* If traffic class doesn't support a full MTU sized
+ * frame, make sure to enable oversize frame dropping
+ * for frames larger than the smallest that would fit.
+ */
+ max_sdu = div_u64(min_gate_len[tc] * 1000,
+ picos_per_byte);
+ /* A TC gate may be completely closed, which is a
+ * special case where all packets are oversized.
+ * Any limit smaller than 64 octets accomplishes this
+ */
+ if (!max_sdu)
+ max_sdu = 1;
+ /* Take L1 overhead into account, but just don't allow
+ * max_sdu to go negative or to 0. Here we use 20
+ * because QSYS_MAXSDU_CFG_* already counts the 4 FCS
+ * octets as part of packet size.
+ */
+ if (max_sdu > 20)
+ max_sdu -= 20;
+ dev_info(ocelot->dev,
+ "port %d tc %d min gate length %llu"
+ " ns not enough for max frame size %d at %d"
+ " Mbps, dropping frames over %d"
+ " octets including FCS\n",
+ port, tc, min_gate_len[tc], maxlen, speed,
+ max_sdu);
+ }
+
+ /* ocelot_write_rix is a macro that concatenates
+ * QSYS_MAXSDU_CFG_* with _RSZ, so we need to spell out
+ * the writes to each traffic class
+ */
+ switch (tc) {
+ case 0:
+ ocelot_write_rix(ocelot, max_sdu, QSYS_QMAXSDU_CFG_0,
+ port);
+ break;
+ case 1:
+ ocelot_write_rix(ocelot, max_sdu, QSYS_QMAXSDU_CFG_1,
+ port);
+ break;
+ case 2:
+ ocelot_write_rix(ocelot, max_sdu, QSYS_QMAXSDU_CFG_2,
+ port);
+ break;
+ case 3:
+ ocelot_write_rix(ocelot, max_sdu, QSYS_QMAXSDU_CFG_3,
+ port);
+ break;
+ case 4:
+ ocelot_write_rix(ocelot, max_sdu, QSYS_QMAXSDU_CFG_4,
+ port);
+ break;
+ case 5:
+ ocelot_write_rix(ocelot, max_sdu, QSYS_QMAXSDU_CFG_5,
+ port);
+ break;
+ case 6:
+ ocelot_write_rix(ocelot, max_sdu, QSYS_QMAXSDU_CFG_6,
+ port);
+ break;
+ case 7:
+ ocelot_write_rix(ocelot, max_sdu, QSYS_QMAXSDU_CFG_7,
+ port);
+ break;
+ }
+ }
+
+ ocelot_write_rix(ocelot, maxlen, QSYS_PORT_MAX_SDU, port);
+}
+
static void vsc9959_sched_speed_set(struct ocelot *ocelot, int port,
u32 speed)
{
+ struct ocelot_port *ocelot_port = ocelot->ports[port];
u8 tas_speed;
switch (speed) {
QSYS_TAG_CONFIG_LINK_SPEED(tas_speed),
QSYS_TAG_CONFIG_LINK_SPEED_M,
QSYS_TAG_CONFIG, port);
+
+ mutex_lock(&ocelot->tas_lock);
+
+ if (ocelot_port->taprio)
+ vsc9959_tas_guard_bands_update(ocelot, port);
+
+ mutex_unlock(&ocelot->tas_lock);
}
static void vsc9959_new_base_time(struct ocelot *ocelot, ktime_t base_time,
taprio_offload_free(ocelot_port->taprio);
ocelot_port->taprio = NULL;
+ vsc9959_tas_guard_bands_update(ocelot, port);
+
mutex_unlock(&ocelot->tas_lock);
return 0;
}
goto err;
ocelot_port->taprio = taprio_offload_get(taprio);
+ vsc9959_tas_guard_bands_update(ocelot, port);
err:
mutex_unlock(&ocelot->tas_lock);
.port_modes = vsc9959_port_modes,
.port_setup_tc = vsc9959_port_setup_tc,
.port_sched_speed_set = vsc9959_sched_speed_set,
+ .tas_guard_bands_update = vsc9959_tas_guard_bands_update,
.init_regmap = ocelot_regmap_init,
};