[PATCH] phy: cadence: torrent: add support for three or more links using 2 protocols
Hrushikesh Salunke
h-salunke at ti.com
Fri Jun 13 08:21:21 CEST 2025
This is a port of the corresponding commit in the Linux kernel which
adds the same support for the Cadence Torrent driver[0]. The commit
message below is taken as-is from the Linux kernel commit being ported.
The Torrent SERDES can support at most two different protocols (PHY types).
This only mandates that the device-tree sub-nodes used to represent the
configuration should describe links with at-most two different protocols.
The existing implementation however imposes an artificial constraint that
allows only two links (device-tree sub-nodes). As long as at-most two
protocols are chosen, using more than two links to describe them in an
alternating configuration is still a valid configuration of the Torrent
SERDES.
A 3-Link 2-Protocol configuration of the 4-Lane SERDES can be:
Lane 0 => Protocol 1 => Link 1
Lane 1 => Protocol 1 => Link 1
Lane 2 => Protocol 2 => Link 2
Lane 3 => Protocol 1 => Link 3
A 4-Link 2-Protocol configuration of the 4-Lane SERDES can be:
Lane 0 => Protocol 1 => Link 1
Lane 1 => Protocol 2 => Link 2
Lane 2 => Protocol 1 => Link 3
Lane 3 => Protocol 2 => Link 4
[0] https://github.com/torvalds/linux/commit/5b7b83a9839be643410c31d56f17c2d430245813
Signed-off-by: Hrushikesh Salunke <h-salunke at ti.com>
---
This patch is based on commit
59d00e20fce Merge tag 'v2025.07-rc4' into next
drivers/phy/cadence/phy-cadence-torrent.c | 225 +++++++++++++---------
1 file changed, 130 insertions(+), 95 deletions(-)
diff --git a/drivers/phy/cadence/phy-cadence-torrent.c b/drivers/phy/cadence/phy-cadence-torrent.c
index d4e8ece4935..1f566d082f9 100644
--- a/drivers/phy/cadence/phy-cadence-torrent.c
+++ b/drivers/phy/cadence/phy-cadence-torrent.c
@@ -240,6 +240,7 @@ struct cdns_torrent_inst {
struct cdns_torrent_phy {
void __iomem *sd_base; /* SD0801 register base */
+ u32 protocol_bitmask;
size_t size;
struct reset_control *phy_rst;
struct udevice *dev;
@@ -432,124 +433,155 @@ static int cdns_torrent_phy_configure_multilink(struct cdns_torrent_phy *cdns_ph
struct cdns_reg_pairs *reg_pairs;
enum cdns_torrent_ssc_mode ssc;
struct regmap *regmap;
- u32 num_regs;
+ u32 num_regs, num_protocols, protocol;
+
+ num_protocols = hweight32(cdns_phy->protocol_bitmask);
- /* Maximum 2 links (subnodes) are supported */
- if (cdns_phy->nsubnodes != 2)
+ /* Maximum 2 protocols are supported */
+ if (num_protocols > 2) {
+ dev_err(cdns_phy->dev, "at most 2 protocols are supported\n");
return -EINVAL;
+ }
- phy_t1 = cdns_phy->phys[0].phy_type;
- phy_t2 = cdns_phy->phys[1].phy_type;
+ if (cdns_phy->nsubnodes == 2) {
+ phy_t1 = cdns_phy->phys[0].phy_type;
+ phy_t2 = cdns_phy->phys[1].phy_type;
+ } else {
+ if (num_protocols != 2) {
+ dev_err(cdns_phy->dev, "incorrect representation of link\n");
+ return -EINVAL;
+ }
+ phy_t1 = __ffs(cdns_phy->protocol_bitmask);
+ phy_t2 = __fls(cdns_phy->protocol_bitmask);
+ }
- /*
- * First configure the PHY for first link with phy_t1. Geth the array
- * values are [phy_t1][phy_t2][ssc].
+ /**
+ * Configure all links with the protocol phy_t1 first followed by
+ * configuring all links with the protocol phy_t2.
+ *
+ * When phy_t1 = phy_t2, it is a single protocol and configuration
+ * is performed with a single iteration of the protocol and multiple
+ * iterations over the sub-nodes (links).
+ *
+ * When phy_t1 != phy_t2, there are two protocols and configuration
+ * is performed by iterating over all sub-nodes matching the first
+ * protocol and configuring them first, followed by iterating over
+ * all sub-nodes matching the second protocol and configuring them
+ * next.
*/
- for (node = 0; node < cdns_phy->nsubnodes; node++) {
- if (node == 1) {
- /*
- * If fist link with phy_t1 is configured, then
- * configure the PHY for second link with phy_t2.
- * Get the array values as [phy_t2][phy_t1][ssc]
- */
+
+ for (protocol = 0; protocol < num_protocols; protocol++) {
+ /**
+ * For the case where num_protocols is 1,
+ * phy_t1 = phy_t2 and the swap is unnecessary.
+ *
+ * Swapping phy_t1 and phy_t2 is only required when the
+ * number of protocols is 2 and there are 2 or more links.
+ */
+ if (protocol == 1) {
tmp_phy_type = phy_t1;
phy_t1 = phy_t2;
phy_t2 = tmp_phy_type;
}
- mlane = cdns_phy->phys[node].mlane;
- ssc = cdns_phy->phys[node].ssc_mode;
- num_lanes = cdns_phy->phys[node].num_lanes;
+ for (node = 0; node < cdns_phy->nsubnodes; node++) {
+ if (cdns_phy->phys[node].phy_type != phy_t1)
+ continue;
- /**
- * PHY configuration specific registers:
- * link_cmn_vals depend on combination of PHY types being
- * configured and are common for both PHY types, so array
- * values should be same for [phy_t1][phy_t2][ssc] and
- * [phy_t2][phy_t1][ssc].
- * xcvr_diag_vals also depend on combination of PHY types
- * being configured, but these can be different for particular
- * PHY type and are per lane.
- */
- link_cmn_vals = init_data->link_cmn_vals[phy_t1][phy_t2][ssc];
- if (link_cmn_vals) {
- reg_pairs = link_cmn_vals->reg_pairs;
- num_regs = link_cmn_vals->num_regs;
- regmap = cdns_phy->regmap_common_cdb;
+ mlane = cdns_phy->phys[node].mlane;
+ ssc = cdns_phy->phys[node].ssc_mode;
+ num_lanes = cdns_phy->phys[node].num_lanes;
/**
- * First array value in link_cmn_vals must be of
- * PHY_PLL_CFG register
+ * PHY configuration specific registers:
+ * link_cmn_vals depend on combination of PHY types being
+ * configured and are common for both PHY types, so array
+ * values should be same for [phy_t1][phy_t2][ssc] and
+ * [phy_t2][phy_t1][ssc].
+ * xcvr_diag_vals also depend on combination of PHY types
+ * being configured, but these can be different for particular
+ * PHY type and are per lane.
*/
- regmap_field_write(cdns_phy->phy_pll_cfg,
- reg_pairs[0].val);
-
- for (i = 1; i < num_regs; i++)
- regmap_write(regmap, reg_pairs[i].off,
- reg_pairs[i].val);
- }
+ link_cmn_vals = init_data->link_cmn_vals[phy_t1][phy_t2][ssc];
+ if (link_cmn_vals) {
+ reg_pairs = link_cmn_vals->reg_pairs;
+ num_regs = link_cmn_vals->num_regs;
+ regmap = cdns_phy->regmap_common_cdb;
+
+ /**
+ * First array value in link_cmn_vals must be of
+ * PHY_PLL_CFG register
+ */
+ regmap_field_write(cdns_phy->phy_pll_cfg,
+ reg_pairs[0].val);
+
+ for (i = 1; i < num_regs; i++)
+ regmap_write(regmap, reg_pairs[i].off,
+ reg_pairs[i].val);
+ }
- xcvr_diag_vals = init_data->xcvr_diag_vals[phy_t1][phy_t2][ssc];
- if (xcvr_diag_vals) {
- reg_pairs = xcvr_diag_vals->reg_pairs;
- num_regs = xcvr_diag_vals->num_regs;
- for (i = 0; i < num_lanes; i++) {
- regmap = cdns_phy->regmap_tx_lane_cdb[i + mlane];
- for (j = 0; j < num_regs; j++)
- regmap_write(regmap, reg_pairs[j].off,
- reg_pairs[j].val);
+ xcvr_diag_vals = init_data->xcvr_diag_vals[phy_t1][phy_t2][ssc];
+ if (xcvr_diag_vals) {
+ reg_pairs = xcvr_diag_vals->reg_pairs;
+ num_regs = xcvr_diag_vals->num_regs;
+ for (i = 0; i < num_lanes; i++) {
+ regmap = cdns_phy->regmap_tx_lane_cdb[i + mlane];
+ for (j = 0; j < num_regs; j++)
+ regmap_write(regmap, reg_pairs[j].off,
+ reg_pairs[j].val);
+ }
}
- }
- /* PHY PCS common registers configurations */
- pcs_cmn_vals = init_data->pcs_cmn_vals[phy_t1][phy_t2][ssc];
- if (pcs_cmn_vals) {
- reg_pairs = pcs_cmn_vals->reg_pairs;
- num_regs = pcs_cmn_vals->num_regs;
- regmap = cdns_phy->regmap_phy_pcs_common_cdb;
- for (i = 0; i < num_regs; i++)
- regmap_write(regmap, reg_pairs[i].off,
- reg_pairs[i].val);
- }
+ /* PHY PCS common registers configurations */
+ pcs_cmn_vals = init_data->pcs_cmn_vals[phy_t1][phy_t2][ssc];
+ if (pcs_cmn_vals) {
+ reg_pairs = pcs_cmn_vals->reg_pairs;
+ num_regs = pcs_cmn_vals->num_regs;
+ regmap = cdns_phy->regmap_phy_pcs_common_cdb;
+ for (i = 0; i < num_regs; i++)
+ regmap_write(regmap, reg_pairs[i].off,
+ reg_pairs[i].val);
+ }
- /* PMA common registers configurations */
- cmn_vals = init_data->cmn_vals[phy_t1][phy_t2][ssc];
- if (cmn_vals) {
- reg_pairs = cmn_vals->reg_pairs;
- num_regs = cmn_vals->num_regs;
- regmap = cdns_phy->regmap_common_cdb;
- for (i = 0; i < num_regs; i++)
- regmap_write(regmap, reg_pairs[i].off,
- reg_pairs[i].val);
- }
+ /* PMA common registers configurations */
+ cmn_vals = init_data->cmn_vals[phy_t1][phy_t2][ssc];
+ if (cmn_vals) {
+ reg_pairs = cmn_vals->reg_pairs;
+ num_regs = cmn_vals->num_regs;
+ regmap = cdns_phy->regmap_common_cdb;
+ for (i = 0; i < num_regs; i++)
+ regmap_write(regmap, reg_pairs[i].off,
+ reg_pairs[i].val);
+ }
- /* PMA TX lane registers configurations */
- tx_ln_vals = init_data->tx_ln_vals[phy_t1][phy_t2][ssc];
- if (tx_ln_vals) {
- reg_pairs = tx_ln_vals->reg_pairs;
- num_regs = tx_ln_vals->num_regs;
- for (i = 0; i < num_lanes; i++) {
- regmap = cdns_phy->regmap_tx_lane_cdb[i + mlane];
- for (j = 0; j < num_regs; j++)
- regmap_write(regmap, reg_pairs[j].off,
- reg_pairs[j].val);
+ /* PMA TX lane registers configurations */
+ tx_ln_vals = init_data->tx_ln_vals[phy_t1][phy_t2][ssc];
+ if (tx_ln_vals) {
+ reg_pairs = tx_ln_vals->reg_pairs;
+ num_regs = tx_ln_vals->num_regs;
+ for (i = 0; i < num_lanes; i++) {
+ regmap = cdns_phy->regmap_tx_lane_cdb[i + mlane];
+ for (j = 0; j < num_regs; j++)
+ regmap_write(regmap, reg_pairs[j].off,
+ reg_pairs[j].val);
+ }
}
- }
- /* PMA RX lane registers configurations */
- rx_ln_vals = init_data->rx_ln_vals[phy_t1][phy_t2][ssc];
- if (rx_ln_vals) {
- reg_pairs = rx_ln_vals->reg_pairs;
- num_regs = rx_ln_vals->num_regs;
- for (i = 0; i < num_lanes; i++) {
- regmap = cdns_phy->regmap_rx_lane_cdb[i + mlane];
- for (j = 0; j < num_regs; j++)
- regmap_write(regmap, reg_pairs[j].off,
- reg_pairs[j].val);
+ /* PMA RX lane registers configurations */
+ rx_ln_vals = init_data->rx_ln_vals[phy_t1][phy_t2][ssc];
+ if (rx_ln_vals) {
+ reg_pairs = rx_ln_vals->reg_pairs;
+ num_regs = rx_ln_vals->num_regs;
+ for (i = 0; i < num_lanes; i++) {
+ regmap = cdns_phy->regmap_rx_lane_cdb[i + mlane];
+ for (j = 0; j < num_regs; j++)
+ regmap_write(regmap, reg_pairs[j].off,
+ reg_pairs[j].val);
+ }
}
- }
- reset_deassert_bulk(cdns_phy->phys[node].lnk_rst);
+ reset_deassert_bulk(cdns_phy->phys[node].lnk_rst);
+ }
}
/* Take the PHY out of reset */
@@ -575,6 +607,7 @@ static int cdns_torrent_phy_probe(struct udevice *dev)
/* Get init data for this phy */
data = (struct cdns_torrent_data *)dev_get_driver_data(dev);
cdns_phy->init_data = data;
+ cdns_phy->protocol_bitmask = 0;
cdns_phy->phy_rst = devm_reset_control_get_by_index(dev, 0);
if (IS_ERR(cdns_phy->phy_rst)) {
@@ -677,6 +710,8 @@ static int cdns_torrent_phy_probe(struct udevice *dev)
/* Get SSC mode */
ofnode_read_u32(child, "cdns,ssc-mode",
&cdns_phy->phys[node].ssc_mode);
+
+ cdns_phy->protocol_bitmask |= BIT(cdns_phy->phys[node].phy_type);
node++;
}
--
2.34.1
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