// SPDX-License-Identifier: GPL-2.0+#include <linux/linkmode.h> /** * linkmode_resolve_pause - resolve the allowable pause modes * @local_adv: local advertisement in ethtool format * @partner_adv: partner advertisement in ethtool format * @tx_pause: pointer to bool to indicate whether transmit pause should be * enabled. * @rx_pause: pointer to bool to indicate whether receive pause should be * enabled. * * Flow control is resolved according to our and the link partners * advertisements using the following drawn from the 802.3 specs: *  Local device  Link partner *  Pause AsymDir Pause AsymDir Result *    0     X       0     X     Disabled *    0     1       1     0     Disabled *    0     1       1     1     TX *    1     0       0     X     Disabled *    1     X       1     X     TX+RX *    1     1       0     1     RX */void linkmode_resolve_pause(const unsigned long *local_adv,			    const unsigned long *partner_adv,			    bool *tx_pause, bool *rx_pause){	__ETHTOOL_DECLARE_LINK_MODE_MASK(m); 	linkmode_and(m, local_adv, partner_adv);	if (linkmode_test_bit(ETHTOOL_LINK_MODE_Pause_BIT, m)) {		*tx_pause = true;		*rx_pause = true;	} else if (linkmode_test_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT, m)) {		*tx_pause = linkmode_test_bit(ETHTOOL_LINK_MODE_Pause_BIT,					      partner_adv);		*rx_pause = linkmode_test_bit(ETHTOOL_LINK_MODE_Pause_BIT,					      local_adv);	} else {		*tx_pause = false;		*rx_pause = false;	}}EXPORT_SYMBOL_GPL(linkmode_resolve_pause); /** * linkmode_set_pause - set the pause mode advertisement * @advertisement: advertisement in ethtool format * @tx: boolean from ethtool struct ethtool_pauseparam tx_pause member * @rx: boolean from ethtool struct ethtool_pauseparam rx_pause member * * Configure the advertised Pause and Asym_Pause bits according to the * capabilities of provided in @tx and @rx. * * We convert as follows: *  tx rx  Pause AsymDir *  0  0   0     0 *  0  1   1     1 *  1  0   0     1 *  1  1   1     0 * * Note: this translation from ethtool tx/rx notation to the advertisement * is actually very problematical. Here are some examples: * * For tx=0 rx=1, meaning transmit is unsupported, receive is supported: * *  Local device  Link partner *  Pause AsymDir Pause AsymDir Result *    1     1       1     0     TX + RX - but we have no TX support. *    1     1       0     1	Only this gives RX only * * For tx=1 rx=1, meaning we have the capability to transmit and receive * pause frames: * *  Local device  Link partner *  Pause AsymDir Pause AsymDir Result *    1     0       0     1     Disabled - but since we do support tx and rx, *				this should resolve to RX only. * * Hence, asking for: *  rx=1 tx=0 gives Pause+AsymDir advertisement, but we may end up *            resolving to tx+rx pause or only rx pause depending on *            the partners advertisement. *  rx=0 tx=1 gives AsymDir only, which will only give tx pause if *            the partners advertisement allows it. *  rx=1 tx=1 gives Pause only, which will only allow tx+rx pause *            if the other end also advertises Pause. */void linkmode_set_pause(unsigned long *advertisement, bool tx, bool rx){	linkmode_mod_bit(ETHTOOL_LINK_MODE_Pause_BIT, advertisement, rx);	linkmode_mod_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT, advertisement,			 rx ^ tx);}EXPORT_SYMBOL_GPL(linkmode_set_pause);