diff options
| -rw-r--r-- | net/dsa/tag_8021q.c | 60 |
1 files changed, 50 insertions, 10 deletions
diff --git a/net/dsa/tag_8021q.c b/net/dsa/tag_8021q.c index 4adec6bbfe59..65a35e976d7b 100644 --- a/net/dsa/tag_8021q.c +++ b/net/dsa/tag_8021q.c @@ -11,20 +11,59 @@ #include "dsa_priv.h" -/* Allocating two VLAN tags per port - one for the RX VID and - * the other for the TX VID - see below +/* Binary structure of the fake 12-bit VID field (when the TPID is + * ETH_P_DSA_8021Q): + * + * | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | + * +-----------+-----+-----------------+-----------+-----------------------+ + * | DIR | RSV | SWITCH_ID | RSV | PORT | + * +-----------+-----+-----------------+-----------+-----------------------+ + * + * DIR - VID[11:10]: + * Direction flags. + * * 1 (0b01) for RX VLAN, + * * 2 (0b10) for TX VLAN. + * These values make the special VIDs of 0, 1 and 4095 to be left + * unused by this coding scheme. + * + * RSV - VID[9]: + * To be used for further expansion of SWITCH_ID or for other purposes. + * + * SWITCH_ID - VID[8:6]: + * Index of switch within DSA tree. Must be between 0 and + * DSA_MAX_SWITCHES - 1. + * + * RSV - VID[5:4]: + * To be used for further expansion of PORT or for other purposes. + * + * PORT - VID[3:0]: + * Index of switch port. Must be between 0 and DSA_MAX_PORTS - 1. */ -#define DSA_8021Q_VID_RANGE (DSA_MAX_SWITCHES * DSA_MAX_PORTS) -#define DSA_8021Q_VID_BASE (VLAN_N_VID - 2 * DSA_8021Q_VID_RANGE - 1) -#define DSA_8021Q_RX_VID_BASE (DSA_8021Q_VID_BASE) -#define DSA_8021Q_TX_VID_BASE (DSA_8021Q_VID_BASE + DSA_8021Q_VID_RANGE) + +#define DSA_8021Q_DIR_SHIFT 10 +#define DSA_8021Q_DIR_MASK GENMASK(11, 10) +#define DSA_8021Q_DIR(x) (((x) << DSA_8021Q_DIR_SHIFT) & \ + DSA_8021Q_DIR_MASK) +#define DSA_8021Q_DIR_RX DSA_8021Q_DIR(1) +#define DSA_8021Q_DIR_TX DSA_8021Q_DIR(2) + +#define DSA_8021Q_SWITCH_ID_SHIFT 6 +#define DSA_8021Q_SWITCH_ID_MASK GENMASK(8, 6) +#define DSA_8021Q_SWITCH_ID(x) (((x) << DSA_8021Q_SWITCH_ID_SHIFT) & \ + DSA_8021Q_SWITCH_ID_MASK) + +#define DSA_8021Q_PORT_SHIFT 0 +#define DSA_8021Q_PORT_MASK GENMASK(3, 0) +#define DSA_8021Q_PORT(x) (((x) << DSA_8021Q_PORT_SHIFT) & \ + DSA_8021Q_PORT_MASK) /* Returns the VID to be inserted into the frame from xmit for switch steering * instructions on egress. Encodes switch ID and port ID. */ u16 dsa_8021q_tx_vid(struct dsa_switch *ds, int port) { - return DSA_8021Q_TX_VID_BASE + (DSA_MAX_PORTS * ds->index) + port; + return DSA_8021Q_DIR_TX | DSA_8021Q_SWITCH_ID(ds->index) | + DSA_8021Q_PORT(port); } EXPORT_SYMBOL_GPL(dsa_8021q_tx_vid); @@ -33,21 +72,22 @@ EXPORT_SYMBOL_GPL(dsa_8021q_tx_vid); */ u16 dsa_8021q_rx_vid(struct dsa_switch *ds, int port) { - return DSA_8021Q_RX_VID_BASE + (DSA_MAX_PORTS * ds->index) + port; + return DSA_8021Q_DIR_RX | DSA_8021Q_SWITCH_ID(ds->index) | + DSA_8021Q_PORT(port); } EXPORT_SYMBOL_GPL(dsa_8021q_rx_vid); /* Returns the decoded switch ID from the RX VID. */ int dsa_8021q_rx_switch_id(u16 vid) { - return ((vid - DSA_8021Q_RX_VID_BASE) / DSA_MAX_PORTS); + return (vid & DSA_8021Q_SWITCH_ID_MASK) >> DSA_8021Q_SWITCH_ID_SHIFT; } EXPORT_SYMBOL_GPL(dsa_8021q_rx_switch_id); /* Returns the decoded port ID from the RX VID. */ int dsa_8021q_rx_source_port(u16 vid) { - return ((vid - DSA_8021Q_RX_VID_BASE) % DSA_MAX_PORTS); + return (vid & DSA_8021Q_PORT_MASK) >> DSA_8021Q_PORT_SHIFT; } EXPORT_SYMBOL_GPL(dsa_8021q_rx_source_port); |