xref: /freebsd/sys/dev/e1000/e1000_vf.c (revision 71625ec9ad2a9bc8c09784fbd23b759830e0ee5f)
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4   Copyright (c) 2001-2020, Intel Corporation
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34 
35 
36 #include "e1000_api.h"
37 
38 
39 static s32 e1000_init_phy_params_vf(struct e1000_hw *hw);
40 static s32 e1000_init_nvm_params_vf(struct e1000_hw *hw);
41 static void e1000_release_vf(struct e1000_hw *hw);
42 static s32 e1000_acquire_vf(struct e1000_hw *hw);
43 static s32 e1000_setup_link_vf(struct e1000_hw *hw);
44 static s32 e1000_get_bus_info_pcie_vf(struct e1000_hw *hw);
45 static s32 e1000_init_mac_params_vf(struct e1000_hw *hw);
46 static s32 e1000_check_for_link_vf(struct e1000_hw *hw);
47 static s32 e1000_get_link_up_info_vf(struct e1000_hw *hw, u16 *speed,
48 				     u16 *duplex);
49 static s32 e1000_init_hw_vf(struct e1000_hw *hw);
50 static s32 e1000_reset_hw_vf(struct e1000_hw *hw);
51 static void e1000_update_mc_addr_list_vf(struct e1000_hw *hw, u8 *, u32);
52 static int  e1000_rar_set_vf(struct e1000_hw *, u8 *, u32);
53 static s32 e1000_read_mac_addr_vf(struct e1000_hw *);
54 
55 /**
56  *  e1000_init_phy_params_vf - Inits PHY params
57  *  @hw: pointer to the HW structure
58  *
59  *  Doesn't do much - there's no PHY available to the VF.
60  **/
e1000_init_phy_params_vf(struct e1000_hw * hw)61 static s32 e1000_init_phy_params_vf(struct e1000_hw *hw)
62 {
63 	DEBUGFUNC("e1000_init_phy_params_vf");
64 	hw->phy.type = e1000_phy_vf;
65 	hw->phy.ops.acquire = e1000_acquire_vf;
66 	hw->phy.ops.release = e1000_release_vf;
67 
68 	return E1000_SUCCESS;
69 }
70 
71 /**
72  *  e1000_init_nvm_params_vf - Inits NVM params
73  *  @hw: pointer to the HW structure
74  *
75  *  Doesn't do much - there's no NVM available to the VF.
76  **/
e1000_init_nvm_params_vf(struct e1000_hw * hw)77 static s32 e1000_init_nvm_params_vf(struct e1000_hw *hw)
78 {
79 	DEBUGFUNC("e1000_init_nvm_params_vf");
80 	hw->nvm.type = e1000_nvm_none;
81 	hw->nvm.ops.acquire = e1000_acquire_vf;
82 	hw->nvm.ops.release = e1000_release_vf;
83 
84 	return E1000_SUCCESS;
85 }
86 
87 /**
88  *  e1000_init_mac_params_vf - Inits MAC params
89  *  @hw: pointer to the HW structure
90  **/
e1000_init_mac_params_vf(struct e1000_hw * hw)91 static s32 e1000_init_mac_params_vf(struct e1000_hw *hw)
92 {
93 	struct e1000_mac_info *mac = &hw->mac;
94 
95 	DEBUGFUNC("e1000_init_mac_params_vf");
96 
97 	/* Set media type */
98 	/*
99 	 * Virtual functions don't care what they're media type is as they
100 	 * have no direct access to the PHY, or the media.  That is handled
101 	 * by the physical function driver.
102 	 */
103 	hw->phy.media_type = e1000_media_type_unknown;
104 
105 	/* No ASF features for the VF driver */
106 	mac->asf_firmware_present = false;
107 	/* ARC subsystem not supported */
108 	mac->arc_subsystem_valid = false;
109 	/* Disable adaptive IFS mode so the generic funcs don't do anything */
110 	mac->adaptive_ifs = false;
111 	/* VF's have no MTA Registers - PF feature only */
112 	mac->mta_reg_count = 128;
113 	/* VF's have no access to RAR entries  */
114 	mac->rar_entry_count = 1;
115 
116 	/* Function pointers */
117 	/* link setup */
118 	mac->ops.setup_link = e1000_setup_link_vf;
119 	/* bus type/speed/width */
120 	mac->ops.get_bus_info = e1000_get_bus_info_pcie_vf;
121 	/* reset */
122 	mac->ops.reset_hw = e1000_reset_hw_vf;
123 	/* hw initialization */
124 	mac->ops.init_hw = e1000_init_hw_vf;
125 	/* check for link */
126 	mac->ops.check_for_link = e1000_check_for_link_vf;
127 	/* link info */
128 	mac->ops.get_link_up_info = e1000_get_link_up_info_vf;
129 	/* multicast address update */
130 	mac->ops.update_mc_addr_list = e1000_update_mc_addr_list_vf;
131 	/* set mac address */
132 	mac->ops.rar_set = e1000_rar_set_vf;
133 	/* read mac address */
134 	mac->ops.read_mac_addr = e1000_read_mac_addr_vf;
135 
136 
137 	return E1000_SUCCESS;
138 }
139 
140 /**
141  *  e1000_init_function_pointers_vf - Inits function pointers
142  *  @hw: pointer to the HW structure
143  **/
e1000_init_function_pointers_vf(struct e1000_hw * hw)144 void e1000_init_function_pointers_vf(struct e1000_hw *hw)
145 {
146 	DEBUGFUNC("e1000_init_function_pointers_vf");
147 
148 	hw->mac.ops.init_params = e1000_init_mac_params_vf;
149 	hw->nvm.ops.init_params = e1000_init_nvm_params_vf;
150 	hw->phy.ops.init_params = e1000_init_phy_params_vf;
151 	hw->mbx.ops.init_params = e1000_init_mbx_params_vf;
152 }
153 
154 /**
155  *  e1000_acquire_vf - Acquire rights to access PHY or NVM.
156  *  @hw: pointer to the HW structure
157  *
158  *  There is no PHY or NVM so we want all attempts to acquire these to fail.
159  *  In addition, the MAC registers to access PHY/NVM don't exist so we don't
160  *  even want any SW to attempt to use them.
161  **/
e1000_acquire_vf(struct e1000_hw E1000_UNUSEDARG * hw)162 static s32 e1000_acquire_vf(struct e1000_hw E1000_UNUSEDARG *hw)
163 {
164 	return -E1000_ERR_PHY;
165 }
166 
167 /**
168  *  e1000_release_vf - Release PHY or NVM
169  *  @hw: pointer to the HW structure
170  *
171  *  There is no PHY or NVM so we want all attempts to acquire these to fail.
172  *  In addition, the MAC registers to access PHY/NVM don't exist so we don't
173  *  even want any SW to attempt to use them.
174  **/
e1000_release_vf(struct e1000_hw E1000_UNUSEDARG * hw)175 static void e1000_release_vf(struct e1000_hw E1000_UNUSEDARG *hw)
176 {
177 	return;
178 }
179 
180 /**
181  *  e1000_setup_link_vf - Sets up link.
182  *  @hw: pointer to the HW structure
183  *
184  *  Virtual functions cannot change link.
185  **/
e1000_setup_link_vf(struct e1000_hw E1000_UNUSEDARG * hw)186 static s32 e1000_setup_link_vf(struct e1000_hw E1000_UNUSEDARG *hw)
187 {
188 	DEBUGFUNC("e1000_setup_link_vf");
189 
190 	return E1000_SUCCESS;
191 }
192 
193 /**
194  *  e1000_get_bus_info_pcie_vf - Gets the bus info.
195  *  @hw: pointer to the HW structure
196  *
197  *  Virtual functions are not really on their own bus.
198  **/
e1000_get_bus_info_pcie_vf(struct e1000_hw * hw)199 static s32 e1000_get_bus_info_pcie_vf(struct e1000_hw *hw)
200 {
201 	struct e1000_bus_info *bus = &hw->bus;
202 
203 	DEBUGFUNC("e1000_get_bus_info_pcie_vf");
204 
205 	/* Do not set type PCI-E because we don't want disable master to run */
206 	bus->type = e1000_bus_type_reserved;
207 	bus->speed = e1000_bus_speed_2500;
208 
209 	return 0;
210 }
211 
212 /**
213  *  e1000_get_link_up_info_vf - Gets link info.
214  *  @hw: pointer to the HW structure
215  *  @speed: pointer to 16 bit value to store link speed.
216  *  @duplex: pointer to 16 bit value to store duplex.
217  *
218  *  Since we cannot read the PHY and get accurate link info, we must rely upon
219  *  the status register's data which is often stale and inaccurate.
220  **/
e1000_get_link_up_info_vf(struct e1000_hw * hw,u16 * speed,u16 * duplex)221 static s32 e1000_get_link_up_info_vf(struct e1000_hw *hw, u16 *speed,
222 				     u16 *duplex)
223 {
224 	s32 status;
225 
226 	DEBUGFUNC("e1000_get_link_up_info_vf");
227 
228 	status = E1000_READ_REG(hw, E1000_STATUS);
229 	if (status & E1000_STATUS_SPEED_1000) {
230 		*speed = SPEED_1000;
231 		DEBUGOUT("1000 Mbs, ");
232 	} else if (status & E1000_STATUS_SPEED_100) {
233 		*speed = SPEED_100;
234 		DEBUGOUT("100 Mbs, ");
235 	} else {
236 		*speed = SPEED_10;
237 		DEBUGOUT("10 Mbs, ");
238 	}
239 
240 	if (status & E1000_STATUS_FD) {
241 		*duplex = FULL_DUPLEX;
242 		DEBUGOUT("Full Duplex\n");
243 	} else {
244 		*duplex = HALF_DUPLEX;
245 		DEBUGOUT("Half Duplex\n");
246 	}
247 
248 	return E1000_SUCCESS;
249 }
250 
251 /**
252  *  e1000_reset_hw_vf - Resets the HW
253  *  @hw: pointer to the HW structure
254  *
255  *  VF's provide a function level reset. This is done using bit 26 of ctrl_reg.
256  *  This is all the reset we can perform on a VF.
257  **/
e1000_reset_hw_vf(struct e1000_hw * hw)258 static s32 e1000_reset_hw_vf(struct e1000_hw *hw)
259 {
260 	struct e1000_mbx_info *mbx = &hw->mbx;
261 	u32 timeout = E1000_VF_INIT_TIMEOUT;
262 	s32 ret_val = -E1000_ERR_MAC_INIT;
263 	u32 ctrl, msgbuf[3];
264 	u8 *addr = (u8 *)(&msgbuf[1]);
265 
266 	DEBUGFUNC("e1000_reset_hw_vf");
267 
268 	DEBUGOUT("Issuing a function level reset to MAC\n");
269 	ctrl = E1000_READ_REG(hw, E1000_CTRL);
270 	E1000_WRITE_REG(hw, E1000_CTRL, ctrl | E1000_CTRL_RST);
271 
272 	/* we cannot reset while the RSTI / RSTD bits are asserted */
273 	while (!mbx->ops.check_for_rst(hw, 0) && timeout) {
274 		timeout--;
275 		usec_delay(5);
276 	}
277 
278 	if (timeout) {
279 		/* mailbox timeout can now become active */
280 		mbx->timeout = E1000_VF_MBX_INIT_TIMEOUT;
281 
282 		msgbuf[0] = E1000_VF_RESET;
283 		mbx->ops.write_posted(hw, msgbuf, 1, 0);
284 
285 		msec_delay(10);
286 
287 		/* set our "perm_addr" based on info provided by PF */
288 		ret_val = mbx->ops.read_posted(hw, msgbuf, 3, 0);
289 		if (!ret_val) {
290 			if (msgbuf[0] == (E1000_VF_RESET |
291 			    E1000_VT_MSGTYPE_ACK))
292 				memcpy(hw->mac.perm_addr, addr, 6);
293 			else
294 				ret_val = -E1000_ERR_MAC_INIT;
295 		}
296 	}
297 
298 	return ret_val;
299 }
300 
301 /**
302  *  e1000_init_hw_vf - Inits the HW
303  *  @hw: pointer to the HW structure
304  *
305  *  Not much to do here except clear the PF Reset indication if there is one.
306  **/
e1000_init_hw_vf(struct e1000_hw * hw)307 static s32 e1000_init_hw_vf(struct e1000_hw *hw)
308 {
309 	DEBUGFUNC("e1000_init_hw_vf");
310 
311 	/* attempt to set and restore our mac address */
312 	e1000_rar_set_vf(hw, hw->mac.addr, 0);
313 
314 	return E1000_SUCCESS;
315 }
316 
317 /**
318  *  e1000_rar_set_vf - set device MAC address
319  *  @hw: pointer to the HW structure
320  *  @addr: pointer to the receive address
321  *  @index receive address array register
322  **/
e1000_rar_set_vf(struct e1000_hw * hw,u8 * addr,u32 E1000_UNUSEDARG index)323 static int e1000_rar_set_vf(struct e1000_hw *hw, u8 *addr,
324 			     u32 E1000_UNUSEDARG index)
325 {
326 	struct e1000_mbx_info *mbx = &hw->mbx;
327 	u32 msgbuf[3];
328 	u8 *msg_addr = (u8 *)(&msgbuf[1]);
329 	s32 ret_val;
330 
331 	memset(msgbuf, 0, 12);
332 	msgbuf[0] = E1000_VF_SET_MAC_ADDR;
333 	memcpy(msg_addr, addr, 6);
334 	ret_val = mbx->ops.write_posted(hw, msgbuf, 3, 0);
335 
336 	if (!ret_val)
337 		ret_val = mbx->ops.read_posted(hw, msgbuf, 3, 0);
338 
339 	msgbuf[0] &= ~E1000_VT_MSGTYPE_CTS;
340 
341 	/* if nacked the address was rejected, use "perm_addr" */
342 	if (!ret_val &&
343 	    (msgbuf[0] == (E1000_VF_SET_MAC_ADDR | E1000_VT_MSGTYPE_NACK)))
344 		e1000_read_mac_addr_vf(hw);
345 
346 	return E1000_SUCCESS;
347 }
348 
349 /**
350  *  e1000_hash_mc_addr_vf - Generate a multicast hash value
351  *  @hw: pointer to the HW structure
352  *  @mc_addr: pointer to a multicast address
353  *
354  *  Generates a multicast address hash value which is used to determine
355  *  the multicast filter table array address and new table value.
356  **/
e1000_hash_mc_addr_vf(struct e1000_hw * hw,u8 * mc_addr)357 static u32 e1000_hash_mc_addr_vf(struct e1000_hw *hw, u8 *mc_addr)
358 {
359 	u32 hash_value, hash_mask;
360 	u8 bit_shift = 0;
361 
362 	DEBUGFUNC("e1000_hash_mc_addr_generic");
363 
364 	/* Register count multiplied by bits per register */
365 	hash_mask = (hw->mac.mta_reg_count * 32) - 1;
366 
367 	/*
368 	 * The bit_shift is the number of left-shifts
369 	 * where 0xFF would still fall within the hash mask.
370 	 */
371 	while (hash_mask >> bit_shift != 0xFF)
372 		bit_shift++;
373 
374 	hash_value = hash_mask & (((mc_addr[4] >> (8 - bit_shift)) |
375 				  (((u16) mc_addr[5]) << bit_shift)));
376 
377 	return hash_value;
378 }
379 
e1000_write_msg_read_ack(struct e1000_hw * hw,u32 * msg,u16 size)380 static void e1000_write_msg_read_ack(struct e1000_hw *hw,
381 				     u32 *msg, u16 size)
382 {
383 	struct e1000_mbx_info *mbx = &hw->mbx;
384 	u32 retmsg[E1000_VFMAILBOX_SIZE];
385 	s32 retval = mbx->ops.write_posted(hw, msg, size, 0);
386 
387 	if (!retval)
388 		mbx->ops.read_posted(hw, retmsg, E1000_VFMAILBOX_SIZE, 0);
389 }
390 
391 /**
392  *  e1000_update_mc_addr_list_vf - Update Multicast addresses
393  *  @hw: pointer to the HW structure
394  *  @mc_addr_list: array of multicast addresses to program
395  *  @mc_addr_count: number of multicast addresses to program
396  *
397  *  Updates the Multicast Table Array.
398  *  The caller must have a packed mc_addr_list of multicast addresses.
399  **/
e1000_update_mc_addr_list_vf(struct e1000_hw * hw,u8 * mc_addr_list,u32 mc_addr_count)400 void e1000_update_mc_addr_list_vf(struct e1000_hw *hw,
401 				  u8 *mc_addr_list, u32 mc_addr_count)
402 {
403 	u32 msgbuf[E1000_VFMAILBOX_SIZE];
404 	u16 *hash_list = (u16 *)&msgbuf[1];
405 	u32 hash_value;
406 	u32 i;
407 
408 	DEBUGFUNC("e1000_update_mc_addr_list_vf");
409 
410 	/* Each entry in the list uses 1 16 bit word.  We have 30
411 	 * 16 bit words available in our HW msg buffer (minus 1 for the
412 	 * msg type).  That's 30 hash values if we pack 'em right.  If
413 	 * there are more than 30 MC addresses to add then punt the
414 	 * extras for now and then add code to handle more than 30 later.
415 	 * It would be unusual for a server to request that many multi-cast
416 	 * addresses except for in large enterprise network environments.
417 	 */
418 
419 	DEBUGOUT1("MC Addr Count = %d\n", mc_addr_count);
420 
421 	msgbuf[0] = E1000_VF_SET_MULTICAST;
422 
423 	if (mc_addr_count > 30) {
424 		msgbuf[0] |= E1000_VF_SET_MULTICAST_OVERFLOW;
425 		mc_addr_count = 30;
426 	}
427 
428 	msgbuf[0] |= mc_addr_count << E1000_VT_MSGINFO_SHIFT;
429 
430 	for (i = 0; i < mc_addr_count; i++) {
431 		hash_value = e1000_hash_mc_addr_vf(hw, mc_addr_list);
432 		DEBUGOUT1("Hash value = 0x%03X\n", hash_value);
433 		hash_list[i] = hash_value & 0x0FFF;
434 		mc_addr_list += ETHER_ADDR_LEN;
435 	}
436 
437 	e1000_write_msg_read_ack(hw, msgbuf, E1000_VFMAILBOX_SIZE);
438 }
439 
440 /**
441  *  e1000_vfta_set_vf - Set/Unset vlan filter table address
442  *  @hw: pointer to the HW structure
443  *  @vid: determines the vfta register and bit to set/unset
444  *  @set: if true then set bit, else clear bit
445  **/
e1000_vfta_set_vf(struct e1000_hw * hw,u16 vid,bool set)446 void e1000_vfta_set_vf(struct e1000_hw *hw, u16 vid, bool set)
447 {
448 	u32 msgbuf[2];
449 
450 	msgbuf[0] = E1000_VF_SET_VLAN;
451 	msgbuf[1] = vid;
452 	/* Setting the 8 bit field MSG INFO to true indicates "add" */
453 	if (set)
454 		msgbuf[0] |= E1000_VF_SET_VLAN_ADD;
455 
456 	e1000_write_msg_read_ack(hw, msgbuf, 2);
457 }
458 
459 /** e1000_rlpml_set_vf - Set the maximum receive packet length
460  *  @hw: pointer to the HW structure
461  *  @max_size: value to assign to max frame size
462  **/
e1000_rlpml_set_vf(struct e1000_hw * hw,u16 max_size)463 void e1000_rlpml_set_vf(struct e1000_hw *hw, u16 max_size)
464 {
465 	u32 msgbuf[2];
466 
467 	msgbuf[0] = E1000_VF_SET_LPE;
468 	msgbuf[1] = max_size;
469 
470 	e1000_write_msg_read_ack(hw, msgbuf, 2);
471 }
472 
473 /**
474  *  e1000_promisc_set_vf - Set flags for Unicast or Multicast promisc
475  *  @hw: pointer to the HW structure
476  *  @uni: boolean indicating unicast promisc status
477  *  @multi: boolean indicating multicast promisc status
478  **/
e1000_promisc_set_vf(struct e1000_hw * hw,enum e1000_promisc_type type)479 s32 e1000_promisc_set_vf(struct e1000_hw *hw, enum e1000_promisc_type type)
480 {
481 	struct e1000_mbx_info *mbx = &hw->mbx;
482 	u32 msgbuf = E1000_VF_SET_PROMISC;
483 	s32 ret_val;
484 
485 	switch (type) {
486 	case e1000_promisc_multicast:
487 		msgbuf |= E1000_VF_SET_PROMISC_MULTICAST;
488 		break;
489 	case e1000_promisc_enabled:
490 		msgbuf |= E1000_VF_SET_PROMISC_MULTICAST;
491 		/* FALLTHROUGH */
492 	case e1000_promisc_unicast:
493 		msgbuf |= E1000_VF_SET_PROMISC_UNICAST;
494 		/* FALLTHROUGH */
495 	case e1000_promisc_disabled:
496 		break;
497 	default:
498 		return -E1000_ERR_MAC_INIT;
499 	}
500 
501 	 ret_val = mbx->ops.write_posted(hw, &msgbuf, 1, 0);
502 
503 	if (!ret_val)
504 		ret_val = mbx->ops.read_posted(hw, &msgbuf, 1, 0);
505 
506 	if (!ret_val && !(msgbuf & E1000_VT_MSGTYPE_ACK))
507 		ret_val = -E1000_ERR_MAC_INIT;
508 
509 	return ret_val;
510 }
511 
512 /**
513  *  e1000_read_mac_addr_vf - Read device MAC address
514  *  @hw: pointer to the HW structure
515  **/
e1000_read_mac_addr_vf(struct e1000_hw * hw)516 static s32 e1000_read_mac_addr_vf(struct e1000_hw *hw)
517 {
518 	int i;
519 
520 	for (i = 0; i < ETHER_ADDR_LEN; i++)
521 		hw->mac.addr[i] = hw->mac.perm_addr[i];
522 
523 	return E1000_SUCCESS;
524 }
525 
526 /**
527  *  e1000_check_for_link_vf - Check for link for a virtual interface
528  *  @hw: pointer to the HW structure
529  *
530  *  Checks to see if the underlying PF is still talking to the VF and
531  *  if it is then it reports the link state to the hardware, otherwise
532  *  it reports link down and returns an error.
533  **/
e1000_check_for_link_vf(struct e1000_hw * hw)534 static s32 e1000_check_for_link_vf(struct e1000_hw *hw)
535 {
536 	struct e1000_mbx_info *mbx = &hw->mbx;
537 	struct e1000_mac_info *mac = &hw->mac;
538 	s32 ret_val = E1000_SUCCESS;
539 	u32 in_msg = 0;
540 
541 	DEBUGFUNC("e1000_check_for_link_vf");
542 
543 	/*
544 	 * We only want to run this if there has been a rst asserted.
545 	 * in this case that could mean a link change, device reset,
546 	 * or a virtual function reset
547 	 */
548 
549 	/* If we were hit with a reset or timeout drop the link */
550 	if (!mbx->ops.check_for_rst(hw, 0) || !mbx->timeout)
551 		mac->get_link_status = true;
552 
553 	if (!mac->get_link_status)
554 		goto out;
555 
556 	/* if link status is down no point in checking to see if pf is up */
557 	if (!(E1000_READ_REG(hw, E1000_STATUS) & E1000_STATUS_LU))
558 		goto out;
559 
560 	/* if the read failed it could just be a mailbox collision, best wait
561 	 * until we are called again and don't report an error */
562 	if (mbx->ops.read(hw, &in_msg, 1, 0))
563 		goto out;
564 
565 	/* if incoming message isn't clear to send we are waiting on response */
566 	if (!(in_msg & E1000_VT_MSGTYPE_CTS)) {
567 		/* message is not CTS and is NACK we have lost CTS status */
568 		if (in_msg & E1000_VT_MSGTYPE_NACK)
569 			ret_val = -E1000_ERR_MAC_INIT;
570 		goto out;
571 	}
572 
573 	/* at this point we know the PF is talking to us, check and see if
574 	 * we are still accepting timeout or if we had a timeout failure.
575 	 * if we failed then we will need to reinit */
576 	if (!mbx->timeout) {
577 		ret_val = -E1000_ERR_MAC_INIT;
578 		goto out;
579 	}
580 
581 	/* if we passed all the tests above then the link is up and we no
582 	 * longer need to check for link */
583 	mac->get_link_status = false;
584 
585 out:
586 	return ret_val;
587 }
588 
589