From: Sean Anderson Date: Tue, 20 Sep 2022 22:12:28 +0000 (-0400) Subject: net: phylink: Document MAC_(A)SYM_PAUSE X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=72bc36956f73ac54f19a7ac7302fb274069bec18;p=linux.git net: phylink: Document MAC_(A)SYM_PAUSE This documents the possible MLO_PAUSE_* settings which can result from different combinations of MAC_(A)SYM_PAUSE. Special note is paid to settings which can result from user configuration (MLO_PAUSE_AN). The autonegotiation results are more-or-less a direct consequence of IEEE 802.3 Table 28B-2. Signed-off-by: Sean Anderson Signed-off-by: David S. Miller --- diff --git a/include/linux/phylink.h b/include/linux/phylink.h index 6d06896fc20d8..1f997e14bf80b 100644 --- a/include/linux/phylink.h +++ b/include/linux/phylink.h @@ -21,6 +21,35 @@ enum { MLO_AN_FIXED, /* Fixed-link mode */ MLO_AN_INBAND, /* In-band protocol */ + /* MAC_SYM_PAUSE and MAC_ASYM_PAUSE are used when configuring our + * autonegotiation advertisement. They correspond to the PAUSE and + * ASM_DIR bits defined by 802.3, respectively. + * + * The following table lists the values of tx_pause and rx_pause which + * might be requested in mac_link_up. The exact values depend on either + * the results of autonegotation (if MLO_PAUSE_AN is set) or user + * configuration (if MLO_PAUSE_AN is not set). + * + * MAC_SYM_PAUSE MAC_ASYM_PAUSE MLO_PAUSE_AN tx_pause/rx_pause + * ============= ============== ============ ================== + * 0 0 0 0/0 + * 0 0 1 0/0 + * 0 1 0 0/0, 0/1, 1/0, 1/1 + * 0 1 1 0/0, 1/0 + * 1 0 0 0/0, 1/1 + * 1 0 1 0/0, 1/1 + * 1 1 0 0/0, 0/1, 1/0, 1/1 + * 1 1 1 0/0, 0/1, 1/1 + * + * If you set MAC_ASYM_PAUSE, the user may request any combination of + * tx_pause and rx_pause. You do not have to support these + * combinations. + * + * However, you should support combinations of tx_pause and rx_pause + * which might be the result of autonegotation. For example, don't set + * MAC_SYM_PAUSE unless your device can support tx_pause and rx_pause + * at the same time. + */ MAC_SYM_PAUSE = BIT(0), MAC_ASYM_PAUSE = BIT(1), MAC_10HD = BIT(2),