xref: /linux/drivers/net/ethernet/intel/igb/e1000_mac.c (revision 58f6259b7a08f8d47d4629609703d358b042f0fd)
1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright(c) 2007 - 2018 Intel Corporation. */
3 
4 #include <linux/if_ether.h>
5 #include <linux/delay.h>
6 #include <linux/pci.h>
7 #include <linux/netdevice.h>
8 #include <linux/etherdevice.h>
9 
10 #include "e1000_mac.h"
11 
12 #include "igb.h"
13 
14 static s32 igb_set_default_fc(struct e1000_hw *hw);
15 static void igb_set_fc_watermarks(struct e1000_hw *hw);
16 
17 /**
18  *  igb_get_bus_info_pcie - Get PCIe bus information
19  *  @hw: pointer to the HW structure
20  *
21  *  Determines and stores the system bus information for a particular
22  *  network interface.  The following bus information is determined and stored:
23  *  bus speed, bus width, type (PCIe), and PCIe function.
24  **/
25 s32 igb_get_bus_info_pcie(struct e1000_hw *hw)
26 {
27 	struct e1000_bus_info *bus = &hw->bus;
28 	s32 ret_val;
29 	u32 reg;
30 	u16 pcie_link_status;
31 
32 	bus->type = e1000_bus_type_pci_express;
33 
34 	ret_val = igb_read_pcie_cap_reg(hw,
35 					PCI_EXP_LNKSTA,
36 					&pcie_link_status);
37 	if (ret_val) {
38 		bus->width = e1000_bus_width_unknown;
39 		bus->speed = e1000_bus_speed_unknown;
40 	} else {
41 		switch (pcie_link_status & PCI_EXP_LNKSTA_CLS) {
42 		case PCI_EXP_LNKSTA_CLS_2_5GB:
43 			bus->speed = e1000_bus_speed_2500;
44 			break;
45 		case PCI_EXP_LNKSTA_CLS_5_0GB:
46 			bus->speed = e1000_bus_speed_5000;
47 			break;
48 		default:
49 			bus->speed = e1000_bus_speed_unknown;
50 			break;
51 		}
52 
53 		bus->width = (enum e1000_bus_width)((pcie_link_status &
54 						     PCI_EXP_LNKSTA_NLW) >>
55 						     PCI_EXP_LNKSTA_NLW_SHIFT);
56 	}
57 
58 	reg = rd32(E1000_STATUS);
59 	bus->func = (reg & E1000_STATUS_FUNC_MASK) >> E1000_STATUS_FUNC_SHIFT;
60 
61 	return 0;
62 }
63 
64 /**
65  *  igb_clear_vfta - Clear VLAN filter table
66  *  @hw: pointer to the HW structure
67  *
68  *  Clears the register array which contains the VLAN filter table by
69  *  setting all the values to 0.
70  **/
71 void igb_clear_vfta(struct e1000_hw *hw)
72 {
73 	u32 offset;
74 
75 	for (offset = E1000_VLAN_FILTER_TBL_SIZE; offset--;)
76 		hw->mac.ops.write_vfta(hw, offset, 0);
77 }
78 
79 /**
80  *  igb_write_vfta - Write value to VLAN filter table
81  *  @hw: pointer to the HW structure
82  *  @offset: register offset in VLAN filter table
83  *  @value: register value written to VLAN filter table
84  *
85  *  Writes value at the given offset in the register array which stores
86  *  the VLAN filter table.
87  **/
88 void igb_write_vfta(struct e1000_hw *hw, u32 offset, u32 value)
89 {
90 	struct igb_adapter *adapter = hw->back;
91 
92 	array_wr32(E1000_VFTA, offset, value);
93 	wrfl();
94 
95 	adapter->shadow_vfta[offset] = value;
96 }
97 
98 /**
99  *  igb_init_rx_addrs - Initialize receive address's
100  *  @hw: pointer to the HW structure
101  *  @rar_count: receive address registers
102  *
103  *  Setups the receive address registers by setting the base receive address
104  *  register to the devices MAC address and clearing all the other receive
105  *  address registers to 0.
106  **/
107 void igb_init_rx_addrs(struct e1000_hw *hw, u16 rar_count)
108 {
109 	u32 i;
110 	u8 mac_addr[ETH_ALEN] = {0};
111 
112 	/* Setup the receive address */
113 	hw_dbg("Programming MAC Address into RAR[0]\n");
114 
115 	hw->mac.ops.rar_set(hw, hw->mac.addr, 0);
116 
117 	/* Zero out the other (rar_entry_count - 1) receive addresses */
118 	hw_dbg("Clearing RAR[1-%u]\n", rar_count-1);
119 	for (i = 1; i < rar_count; i++)
120 		hw->mac.ops.rar_set(hw, mac_addr, i);
121 }
122 
123 /**
124  *  igb_find_vlvf_slot - find the VLAN id or the first empty slot
125  *  @hw: pointer to hardware structure
126  *  @vlan: VLAN id to write to VLAN filter
127  *  @vlvf_bypass: skip VLVF if no match is found
128  *
129  *  return the VLVF index where this VLAN id should be placed
130  *
131  **/
132 static s32 igb_find_vlvf_slot(struct e1000_hw *hw, u32 vlan, bool vlvf_bypass)
133 {
134 	s32 regindex, first_empty_slot;
135 	u32 bits;
136 
137 	/* short cut the special case */
138 	if (vlan == 0)
139 		return 0;
140 
141 	/* if vlvf_bypass is set we don't want to use an empty slot, we
142 	 * will simply bypass the VLVF if there are no entries present in the
143 	 * VLVF that contain our VLAN
144 	 */
145 	first_empty_slot = vlvf_bypass ? -E1000_ERR_NO_SPACE : 0;
146 
147 	/* Search for the VLAN id in the VLVF entries. Save off the first empty
148 	 * slot found along the way.
149 	 *
150 	 * pre-decrement loop covering (IXGBE_VLVF_ENTRIES - 1) .. 1
151 	 */
152 	for (regindex = E1000_VLVF_ARRAY_SIZE; --regindex > 0;) {
153 		bits = rd32(E1000_VLVF(regindex)) & E1000_VLVF_VLANID_MASK;
154 		if (bits == vlan)
155 			return regindex;
156 		if (!first_empty_slot && !bits)
157 			first_empty_slot = regindex;
158 	}
159 
160 	return first_empty_slot ? : -E1000_ERR_NO_SPACE;
161 }
162 
163 /**
164  *  igb_vfta_set - enable or disable vlan in VLAN filter table
165  *  @hw: pointer to the HW structure
166  *  @vlan: VLAN id to add or remove
167  *  @vind: VMDq output index that maps queue to VLAN id
168  *  @vlan_on: if true add filter, if false remove
169  *  @vlvf_bypass: skip VLVF if no match is found
170  *
171  *  Sets or clears a bit in the VLAN filter table array based on VLAN id
172  *  and if we are adding or removing the filter
173  **/
174 s32 igb_vfta_set(struct e1000_hw *hw, u32 vlan, u32 vind,
175 		 bool vlan_on, bool vlvf_bypass)
176 {
177 	struct igb_adapter *adapter = hw->back;
178 	u32 regidx, vfta_delta, vfta, bits;
179 	s32 vlvf_index;
180 
181 	if ((vlan > 4095) || (vind > 7))
182 		return -E1000_ERR_PARAM;
183 
184 	/* this is a 2 part operation - first the VFTA, then the
185 	 * VLVF and VLVFB if VT Mode is set
186 	 * We don't write the VFTA until we know the VLVF part succeeded.
187 	 */
188 
189 	/* Part 1
190 	 * The VFTA is a bitstring made up of 128 32-bit registers
191 	 * that enable the particular VLAN id, much like the MTA:
192 	 *    bits[11-5]: which register
193 	 *    bits[4-0]:  which bit in the register
194 	 */
195 	regidx = vlan / 32;
196 	vfta_delta = BIT(vlan % 32);
197 	vfta = adapter->shadow_vfta[regidx];
198 
199 	/* vfta_delta represents the difference between the current value
200 	 * of vfta and the value we want in the register.  Since the diff
201 	 * is an XOR mask we can just update vfta using an XOR.
202 	 */
203 	vfta_delta &= vlan_on ? ~vfta : vfta;
204 	vfta ^= vfta_delta;
205 
206 	/* Part 2
207 	 * If VT Mode is set
208 	 *   Either vlan_on
209 	 *     make sure the VLAN is in VLVF
210 	 *     set the vind bit in the matching VLVFB
211 	 *   Or !vlan_on
212 	 *     clear the pool bit and possibly the vind
213 	 */
214 	if (!adapter->vfs_allocated_count)
215 		goto vfta_update;
216 
217 	vlvf_index = igb_find_vlvf_slot(hw, vlan, vlvf_bypass);
218 	if (vlvf_index < 0) {
219 		if (vlvf_bypass)
220 			goto vfta_update;
221 		return vlvf_index;
222 	}
223 
224 	bits = rd32(E1000_VLVF(vlvf_index));
225 
226 	/* set the pool bit */
227 	bits |= BIT(E1000_VLVF_POOLSEL_SHIFT + vind);
228 	if (vlan_on)
229 		goto vlvf_update;
230 
231 	/* clear the pool bit */
232 	bits ^= BIT(E1000_VLVF_POOLSEL_SHIFT + vind);
233 
234 	if (!(bits & E1000_VLVF_POOLSEL_MASK)) {
235 		/* Clear VFTA first, then disable VLVF.  Otherwise
236 		 * we run the risk of stray packets leaking into
237 		 * the PF via the default pool
238 		 */
239 		if (vfta_delta)
240 			hw->mac.ops.write_vfta(hw, regidx, vfta);
241 
242 		/* disable VLVF and clear remaining bit from pool */
243 		wr32(E1000_VLVF(vlvf_index), 0);
244 
245 		return 0;
246 	}
247 
248 	/* If there are still bits set in the VLVFB registers
249 	 * for the VLAN ID indicated we need to see if the
250 	 * caller is requesting that we clear the VFTA entry bit.
251 	 * If the caller has requested that we clear the VFTA
252 	 * entry bit but there are still pools/VFs using this VLAN
253 	 * ID entry then ignore the request.  We're not worried
254 	 * about the case where we're turning the VFTA VLAN ID
255 	 * entry bit on, only when requested to turn it off as
256 	 * there may be multiple pools and/or VFs using the
257 	 * VLAN ID entry.  In that case we cannot clear the
258 	 * VFTA bit until all pools/VFs using that VLAN ID have also
259 	 * been cleared.  This will be indicated by "bits" being
260 	 * zero.
261 	 */
262 	vfta_delta = 0;
263 
264 vlvf_update:
265 	/* record pool change and enable VLAN ID if not already enabled */
266 	wr32(E1000_VLVF(vlvf_index), bits | vlan | E1000_VLVF_VLANID_ENABLE);
267 
268 vfta_update:
269 	/* bit was set/cleared before we started */
270 	if (vfta_delta)
271 		hw->mac.ops.write_vfta(hw, regidx, vfta);
272 
273 	return 0;
274 }
275 
276 /**
277  *  igb_check_alt_mac_addr - Check for alternate MAC addr
278  *  @hw: pointer to the HW structure
279  *
280  *  Checks the nvm for an alternate MAC address.  An alternate MAC address
281  *  can be setup by pre-boot software and must be treated like a permanent
282  *  address and must override the actual permanent MAC address.  If an
283  *  alternate MAC address is found it is saved in the hw struct and
284  *  programmed into RAR0 and the function returns success, otherwise the
285  *  function returns an error.
286  **/
287 s32 igb_check_alt_mac_addr(struct e1000_hw *hw)
288 {
289 	u32 i;
290 	s32 ret_val = 0;
291 	u16 offset, nvm_alt_mac_addr_offset, nvm_data;
292 	u8 alt_mac_addr[ETH_ALEN];
293 
294 	/* Alternate MAC address is handled by the option ROM for 82580
295 	 * and newer. SW support not required.
296 	 */
297 	if (hw->mac.type >= e1000_82580)
298 		goto out;
299 
300 	ret_val = hw->nvm.ops.read(hw, NVM_ALT_MAC_ADDR_PTR, 1,
301 				 &nvm_alt_mac_addr_offset);
302 	if (ret_val) {
303 		hw_dbg("NVM Read Error\n");
304 		goto out;
305 	}
306 
307 	if ((nvm_alt_mac_addr_offset == 0xFFFF) ||
308 	    (nvm_alt_mac_addr_offset == 0x0000))
309 		/* There is no Alternate MAC Address */
310 		goto out;
311 
312 	if (hw->bus.func == E1000_FUNC_1)
313 		nvm_alt_mac_addr_offset += E1000_ALT_MAC_ADDRESS_OFFSET_LAN1;
314 	if (hw->bus.func == E1000_FUNC_2)
315 		nvm_alt_mac_addr_offset += E1000_ALT_MAC_ADDRESS_OFFSET_LAN2;
316 
317 	if (hw->bus.func == E1000_FUNC_3)
318 		nvm_alt_mac_addr_offset += E1000_ALT_MAC_ADDRESS_OFFSET_LAN3;
319 	for (i = 0; i < ETH_ALEN; i += 2) {
320 		offset = nvm_alt_mac_addr_offset + (i >> 1);
321 		ret_val = hw->nvm.ops.read(hw, offset, 1, &nvm_data);
322 		if (ret_val) {
323 			hw_dbg("NVM Read Error\n");
324 			goto out;
325 		}
326 
327 		alt_mac_addr[i] = (u8)(nvm_data & 0xFF);
328 		alt_mac_addr[i + 1] = (u8)(nvm_data >> 8);
329 	}
330 
331 	/* if multicast bit is set, the alternate address will not be used */
332 	if (is_multicast_ether_addr(alt_mac_addr)) {
333 		hw_dbg("Ignoring Alternate Mac Address with MC bit set\n");
334 		goto out;
335 	}
336 
337 	/* We have a valid alternate MAC address, and we want to treat it the
338 	 * same as the normal permanent MAC address stored by the HW into the
339 	 * RAR. Do this by mapping this address into RAR0.
340 	 */
341 	hw->mac.ops.rar_set(hw, alt_mac_addr, 0);
342 
343 out:
344 	return ret_val;
345 }
346 
347 /**
348  *  igb_rar_set - Set receive address register
349  *  @hw: pointer to the HW structure
350  *  @addr: pointer to the receive address
351  *  @index: receive address array register
352  *
353  *  Sets the receive address array register at index to the address passed
354  *  in by addr.
355  **/
356 void igb_rar_set(struct e1000_hw *hw, u8 *addr, u32 index)
357 {
358 	u32 rar_low, rar_high;
359 
360 	/* HW expects these in little endian so we reverse the byte order
361 	 * from network order (big endian) to little endian
362 	 */
363 	rar_low = ((u32) addr[0] |
364 		   ((u32) addr[1] << 8) |
365 		    ((u32) addr[2] << 16) | ((u32) addr[3] << 24));
366 
367 	rar_high = ((u32) addr[4] | ((u32) addr[5] << 8));
368 
369 	/* If MAC address zero, no need to set the AV bit */
370 	if (rar_low || rar_high)
371 		rar_high |= E1000_RAH_AV;
372 
373 	/* Some bridges will combine consecutive 32-bit writes into
374 	 * a single burst write, which will malfunction on some parts.
375 	 * The flushes avoid this.
376 	 */
377 	wr32(E1000_RAL(index), rar_low);
378 	wrfl();
379 	wr32(E1000_RAH(index), rar_high);
380 	wrfl();
381 }
382 
383 /**
384  *  igb_mta_set - Set multicast filter table address
385  *  @hw: pointer to the HW structure
386  *  @hash_value: determines the MTA register and bit to set
387  *
388  *  The multicast table address is a register array of 32-bit registers.
389  *  The hash_value is used to determine what register the bit is in, the
390  *  current value is read, the new bit is OR'd in and the new value is
391  *  written back into the register.
392  **/
393 void igb_mta_set(struct e1000_hw *hw, u32 hash_value)
394 {
395 	u32 hash_bit, hash_reg, mta;
396 
397 	/* The MTA is a register array of 32-bit registers. It is
398 	 * treated like an array of (32*mta_reg_count) bits.  We want to
399 	 * set bit BitArray[hash_value]. So we figure out what register
400 	 * the bit is in, read it, OR in the new bit, then write
401 	 * back the new value.  The (hw->mac.mta_reg_count - 1) serves as a
402 	 * mask to bits 31:5 of the hash value which gives us the
403 	 * register we're modifying.  The hash bit within that register
404 	 * is determined by the lower 5 bits of the hash value.
405 	 */
406 	hash_reg = (hash_value >> 5) & (hw->mac.mta_reg_count - 1);
407 	hash_bit = hash_value & 0x1F;
408 
409 	mta = array_rd32(E1000_MTA, hash_reg);
410 
411 	mta |= BIT(hash_bit);
412 
413 	array_wr32(E1000_MTA, hash_reg, mta);
414 	wrfl();
415 }
416 
417 /**
418  *  igb_hash_mc_addr - Generate a multicast hash value
419  *  @hw: pointer to the HW structure
420  *  @mc_addr: pointer to a multicast address
421  *
422  *  Generates a multicast address hash value which is used to determine
423  *  the multicast filter table array address and new table value.  See
424  *  igb_mta_set()
425  **/
426 static u32 igb_hash_mc_addr(struct e1000_hw *hw, u8 *mc_addr)
427 {
428 	u32 hash_value, hash_mask;
429 	u8 bit_shift = 1;
430 
431 	/* Register count multiplied by bits per register */
432 	hash_mask = (hw->mac.mta_reg_count * 32) - 1;
433 
434 	/* For a mc_filter_type of 0, bit_shift is the number of left-shifts
435 	 * where 0xFF would still fall within the hash mask.
436 	 */
437 	while (hash_mask >> bit_shift != 0xFF && bit_shift < 4)
438 		bit_shift++;
439 
440 	/* The portion of the address that is used for the hash table
441 	 * is determined by the mc_filter_type setting.
442 	 * The algorithm is such that there is a total of 8 bits of shifting.
443 	 * The bit_shift for a mc_filter_type of 0 represents the number of
444 	 * left-shifts where the MSB of mc_addr[5] would still fall within
445 	 * the hash_mask.  Case 0 does this exactly.  Since there are a total
446 	 * of 8 bits of shifting, then mc_addr[4] will shift right the
447 	 * remaining number of bits. Thus 8 - bit_shift.  The rest of the
448 	 * cases are a variation of this algorithm...essentially raising the
449 	 * number of bits to shift mc_addr[5] left, while still keeping the
450 	 * 8-bit shifting total.
451 	 *
452 	 * For example, given the following Destination MAC Address and an
453 	 * mta register count of 128 (thus a 4096-bit vector and 0xFFF mask),
454 	 * we can see that the bit_shift for case 0 is 4.  These are the hash
455 	 * values resulting from each mc_filter_type...
456 	 * [0] [1] [2] [3] [4] [5]
457 	 * 01  AA  00  12  34  56
458 	 * LSB                 MSB
459 	 *
460 	 * case 0: hash_value = ((0x34 >> 4) | (0x56 << 4)) & 0xFFF = 0x563
461 	 * case 1: hash_value = ((0x34 >> 3) | (0x56 << 5)) & 0xFFF = 0xAC6
462 	 * case 2: hash_value = ((0x34 >> 2) | (0x56 << 6)) & 0xFFF = 0x163
463 	 * case 3: hash_value = ((0x34 >> 0) | (0x56 << 8)) & 0xFFF = 0x634
464 	 */
465 	switch (hw->mac.mc_filter_type) {
466 	default:
467 	case 0:
468 		break;
469 	case 1:
470 		bit_shift += 1;
471 		break;
472 	case 2:
473 		bit_shift += 2;
474 		break;
475 	case 3:
476 		bit_shift += 4;
477 		break;
478 	}
479 
480 	hash_value = hash_mask & (((mc_addr[4] >> (8 - bit_shift)) |
481 				  (((u16) mc_addr[5]) << bit_shift)));
482 
483 	return hash_value;
484 }
485 
486 /**
487  * igb_i21x_hw_doublecheck - double checks potential HW issue in i21X
488  * @hw: pointer to the HW structure
489  *
490  * Checks if multicast array is wrote correctly
491  * If not then rewrites again to register
492  **/
493 static void igb_i21x_hw_doublecheck(struct e1000_hw *hw)
494 {
495 	int failed_cnt = 3;
496 	bool is_failed;
497 	int i;
498 
499 	do {
500 		is_failed = false;
501 		for (i = hw->mac.mta_reg_count - 1; i >= 0; i--) {
502 			if (array_rd32(E1000_MTA, i) != hw->mac.mta_shadow[i]) {
503 				is_failed = true;
504 				array_wr32(E1000_MTA, i, hw->mac.mta_shadow[i]);
505 				wrfl();
506 			}
507 		}
508 		if (is_failed && --failed_cnt <= 0) {
509 			hw_dbg("Failed to update MTA_REGISTER, too many retries");
510 			break;
511 		}
512 	} while (is_failed);
513 }
514 
515 /**
516  *  igb_update_mc_addr_list - Update Multicast addresses
517  *  @hw: pointer to the HW structure
518  *  @mc_addr_list: array of multicast addresses to program
519  *  @mc_addr_count: number of multicast addresses to program
520  *
521  *  Updates entire Multicast Table Array.
522  *  The caller must have a packed mc_addr_list of multicast addresses.
523  **/
524 void igb_update_mc_addr_list(struct e1000_hw *hw,
525 			     u8 *mc_addr_list, u32 mc_addr_count)
526 {
527 	u32 hash_value, hash_bit, hash_reg;
528 	int i;
529 
530 	/* clear mta_shadow */
531 	memset(&hw->mac.mta_shadow, 0, sizeof(hw->mac.mta_shadow));
532 
533 	/* update mta_shadow from mc_addr_list */
534 	for (i = 0; (u32) i < mc_addr_count; i++) {
535 		hash_value = igb_hash_mc_addr(hw, mc_addr_list);
536 
537 		hash_reg = (hash_value >> 5) & (hw->mac.mta_reg_count - 1);
538 		hash_bit = hash_value & 0x1F;
539 
540 		hw->mac.mta_shadow[hash_reg] |= BIT(hash_bit);
541 		mc_addr_list += (ETH_ALEN);
542 	}
543 
544 	/* replace the entire MTA table */
545 	for (i = hw->mac.mta_reg_count - 1; i >= 0; i--)
546 		array_wr32(E1000_MTA, i, hw->mac.mta_shadow[i]);
547 	wrfl();
548 	if (hw->mac.type == e1000_i210 || hw->mac.type == e1000_i211)
549 		igb_i21x_hw_doublecheck(hw);
550 }
551 
552 /**
553  *  igb_clear_hw_cntrs_base - Clear base hardware counters
554  *  @hw: pointer to the HW structure
555  *
556  *  Clears the base hardware counters by reading the counter registers.
557  **/
558 void igb_clear_hw_cntrs_base(struct e1000_hw *hw)
559 {
560 	rd32(E1000_CRCERRS);
561 	rd32(E1000_SYMERRS);
562 	rd32(E1000_MPC);
563 	rd32(E1000_SCC);
564 	rd32(E1000_ECOL);
565 	rd32(E1000_MCC);
566 	rd32(E1000_LATECOL);
567 	rd32(E1000_COLC);
568 	rd32(E1000_DC);
569 	rd32(E1000_SEC);
570 	rd32(E1000_RLEC);
571 	rd32(E1000_XONRXC);
572 	rd32(E1000_XONTXC);
573 	rd32(E1000_XOFFRXC);
574 	rd32(E1000_XOFFTXC);
575 	rd32(E1000_FCRUC);
576 	rd32(E1000_GPRC);
577 	rd32(E1000_BPRC);
578 	rd32(E1000_MPRC);
579 	rd32(E1000_GPTC);
580 	rd32(E1000_GORCL);
581 	rd32(E1000_GORCH);
582 	rd32(E1000_GOTCL);
583 	rd32(E1000_GOTCH);
584 	rd32(E1000_RNBC);
585 	rd32(E1000_RUC);
586 	rd32(E1000_RFC);
587 	rd32(E1000_ROC);
588 	rd32(E1000_RJC);
589 	rd32(E1000_TORL);
590 	rd32(E1000_TORH);
591 	rd32(E1000_TOTL);
592 	rd32(E1000_TOTH);
593 	rd32(E1000_TPR);
594 	rd32(E1000_TPT);
595 	rd32(E1000_MPTC);
596 	rd32(E1000_BPTC);
597 }
598 
599 /**
600  *  igb_check_for_copper_link - Check for link (Copper)
601  *  @hw: pointer to the HW structure
602  *
603  *  Checks to see of the link status of the hardware has changed.  If a
604  *  change in link status has been detected, then we read the PHY registers
605  *  to get the current speed/duplex if link exists.
606  **/
607 s32 igb_check_for_copper_link(struct e1000_hw *hw)
608 {
609 	struct e1000_mac_info *mac = &hw->mac;
610 	s32 ret_val;
611 	bool link;
612 
613 	/* We only want to go out to the PHY registers to see if Auto-Neg
614 	 * has completed and/or if our link status has changed.  The
615 	 * get_link_status flag is set upon receiving a Link Status
616 	 * Change or Rx Sequence Error interrupt.
617 	 */
618 	if (!mac->get_link_status) {
619 		ret_val = 0;
620 		goto out;
621 	}
622 
623 	/* First we want to see if the MII Status Register reports
624 	 * link.  If so, then we want to get the current speed/duplex
625 	 * of the PHY.
626 	 */
627 	ret_val = igb_phy_has_link(hw, 1, 0, &link);
628 	if (ret_val)
629 		goto out;
630 
631 	if (!link)
632 		goto out; /* No link detected */
633 
634 	mac->get_link_status = false;
635 
636 	/* Check if there was DownShift, must be checked
637 	 * immediately after link-up
638 	 */
639 	igb_check_downshift(hw);
640 
641 	/* If we are forcing speed/duplex, then we simply return since
642 	 * we have already determined whether we have link or not.
643 	 */
644 	if (!mac->autoneg) {
645 		ret_val = -E1000_ERR_CONFIG;
646 		goto out;
647 	}
648 
649 	/* Auto-Neg is enabled.  Auto Speed Detection takes care
650 	 * of MAC speed/duplex configuration.  So we only need to
651 	 * configure Collision Distance in the MAC.
652 	 */
653 	igb_config_collision_dist(hw);
654 
655 	/* Configure Flow Control now that Auto-Neg has completed.
656 	 * First, we need to restore the desired flow control
657 	 * settings because we may have had to re-autoneg with a
658 	 * different link partner.
659 	 */
660 	ret_val = igb_config_fc_after_link_up(hw);
661 	if (ret_val)
662 		hw_dbg("Error configuring flow control\n");
663 
664 out:
665 	return ret_val;
666 }
667 
668 /**
669  *  igb_setup_link - Setup flow control and link settings
670  *  @hw: pointer to the HW structure
671  *
672  *  Determines which flow control settings to use, then configures flow
673  *  control.  Calls the appropriate media-specific link configuration
674  *  function.  Assuming the adapter has a valid link partner, a valid link
675  *  should be established.  Assumes the hardware has previously been reset
676  *  and the transmitter and receiver are not enabled.
677  **/
678 s32 igb_setup_link(struct e1000_hw *hw)
679 {
680 	s32 ret_val = 0;
681 
682 	/* In the case of the phy reset being blocked, we already have a link.
683 	 * We do not need to set it up again.
684 	 */
685 	if (igb_check_reset_block(hw))
686 		goto out;
687 
688 	/* If requested flow control is set to default, set flow control
689 	 * based on the EEPROM flow control settings.
690 	 */
691 	if (hw->fc.requested_mode == e1000_fc_default) {
692 		ret_val = igb_set_default_fc(hw);
693 		if (ret_val)
694 			goto out;
695 	}
696 
697 	/* We want to save off the original Flow Control configuration just
698 	 * in case we get disconnected and then reconnected into a different
699 	 * hub or switch with different Flow Control capabilities.
700 	 */
701 	hw->fc.current_mode = hw->fc.requested_mode;
702 
703 	hw_dbg("After fix-ups FlowControl is now = %x\n", hw->fc.current_mode);
704 
705 	/* Call the necessary media_type subroutine to configure the link. */
706 	ret_val = hw->mac.ops.setup_physical_interface(hw);
707 	if (ret_val)
708 		goto out;
709 
710 	/* Initialize the flow control address, type, and PAUSE timer
711 	 * registers to their default values.  This is done even if flow
712 	 * control is disabled, because it does not hurt anything to
713 	 * initialize these registers.
714 	 */
715 	hw_dbg("Initializing the Flow Control address, type and timer regs\n");
716 	wr32(E1000_FCT, FLOW_CONTROL_TYPE);
717 	wr32(E1000_FCAH, FLOW_CONTROL_ADDRESS_HIGH);
718 	wr32(E1000_FCAL, FLOW_CONTROL_ADDRESS_LOW);
719 
720 	wr32(E1000_FCTTV, hw->fc.pause_time);
721 
722 	igb_set_fc_watermarks(hw);
723 
724 out:
725 
726 	return ret_val;
727 }
728 
729 /**
730  *  igb_config_collision_dist - Configure collision distance
731  *  @hw: pointer to the HW structure
732  *
733  *  Configures the collision distance to the default value and is used
734  *  during link setup. Currently no func pointer exists and all
735  *  implementations are handled in the generic version of this function.
736  **/
737 void igb_config_collision_dist(struct e1000_hw *hw)
738 {
739 	u32 tctl;
740 
741 	tctl = rd32(E1000_TCTL);
742 
743 	tctl &= ~E1000_TCTL_COLD;
744 	tctl |= E1000_COLLISION_DISTANCE << E1000_COLD_SHIFT;
745 
746 	wr32(E1000_TCTL, tctl);
747 	wrfl();
748 }
749 
750 /**
751  *  igb_set_fc_watermarks - Set flow control high/low watermarks
752  *  @hw: pointer to the HW structure
753  *
754  *  Sets the flow control high/low threshold (watermark) registers.  If
755  *  flow control XON frame transmission is enabled, then set XON frame
756  *  tansmission as well.
757  **/
758 static void igb_set_fc_watermarks(struct e1000_hw *hw)
759 {
760 	u32 fcrtl = 0, fcrth = 0;
761 
762 	/* Set the flow control receive threshold registers.  Normally,
763 	 * these registers will be set to a default threshold that may be
764 	 * adjusted later by the driver's runtime code.  However, if the
765 	 * ability to transmit pause frames is not enabled, then these
766 	 * registers will be set to 0.
767 	 */
768 	if (hw->fc.current_mode & e1000_fc_tx_pause) {
769 		/* We need to set up the Receive Threshold high and low water
770 		 * marks as well as (optionally) enabling the transmission of
771 		 * XON frames.
772 		 */
773 		fcrtl = hw->fc.low_water;
774 		if (hw->fc.send_xon)
775 			fcrtl |= E1000_FCRTL_XONE;
776 
777 		fcrth = hw->fc.high_water;
778 	}
779 	wr32(E1000_FCRTL, fcrtl);
780 	wr32(E1000_FCRTH, fcrth);
781 }
782 
783 /**
784  *  igb_set_default_fc - Set flow control default values
785  *  @hw: pointer to the HW structure
786  *
787  *  Read the EEPROM for the default values for flow control and store the
788  *  values.
789  **/
790 static s32 igb_set_default_fc(struct e1000_hw *hw)
791 {
792 	s32 ret_val = 0;
793 	u16 lan_offset;
794 	u16 nvm_data;
795 
796 	/* Read and store word 0x0F of the EEPROM. This word contains bits
797 	 * that determine the hardware's default PAUSE (flow control) mode,
798 	 * a bit that determines whether the HW defaults to enabling or
799 	 * disabling auto-negotiation, and the direction of the
800 	 * SW defined pins. If there is no SW over-ride of the flow
801 	 * control setting, then the variable hw->fc will
802 	 * be initialized based on a value in the EEPROM.
803 	 */
804 	if (hw->mac.type == e1000_i350)
805 		lan_offset = NVM_82580_LAN_FUNC_OFFSET(hw->bus.func);
806 	else
807 		lan_offset = 0;
808 
809 	ret_val = hw->nvm.ops.read(hw, NVM_INIT_CONTROL2_REG + lan_offset,
810 				   1, &nvm_data);
811 	if (ret_val) {
812 		hw_dbg("NVM Read Error\n");
813 		goto out;
814 	}
815 
816 	if ((nvm_data & NVM_WORD0F_PAUSE_MASK) == 0)
817 		hw->fc.requested_mode = e1000_fc_none;
818 	else if ((nvm_data & NVM_WORD0F_PAUSE_MASK) == NVM_WORD0F_ASM_DIR)
819 		hw->fc.requested_mode = e1000_fc_tx_pause;
820 	else
821 		hw->fc.requested_mode = e1000_fc_full;
822 
823 out:
824 	return ret_val;
825 }
826 
827 /**
828  *  igb_force_mac_fc - Force the MAC's flow control settings
829  *  @hw: pointer to the HW structure
830  *
831  *  Force the MAC's flow control settings.  Sets the TFCE and RFCE bits in the
832  *  device control register to reflect the adapter settings.  TFCE and RFCE
833  *  need to be explicitly set by software when a copper PHY is used because
834  *  autonegotiation is managed by the PHY rather than the MAC.  Software must
835  *  also configure these bits when link is forced on a fiber connection.
836  **/
837 s32 igb_force_mac_fc(struct e1000_hw *hw)
838 {
839 	u32 ctrl;
840 	s32 ret_val = 0;
841 
842 	ctrl = rd32(E1000_CTRL);
843 
844 	/* Because we didn't get link via the internal auto-negotiation
845 	 * mechanism (we either forced link or we got link via PHY
846 	 * auto-neg), we have to manually enable/disable transmit an
847 	 * receive flow control.
848 	 *
849 	 * The "Case" statement below enables/disable flow control
850 	 * according to the "hw->fc.current_mode" parameter.
851 	 *
852 	 * The possible values of the "fc" parameter are:
853 	 *      0:  Flow control is completely disabled
854 	 *      1:  Rx flow control is enabled (we can receive pause
855 	 *          frames but not send pause frames).
856 	 *      2:  Tx flow control is enabled (we can send pause frames
857 	 *          but we do not receive pause frames).
858 	 *      3:  Both Rx and TX flow control (symmetric) is enabled.
859 	 *  other:  No other values should be possible at this point.
860 	 */
861 	hw_dbg("hw->fc.current_mode = %u\n", hw->fc.current_mode);
862 
863 	switch (hw->fc.current_mode) {
864 	case e1000_fc_none:
865 		ctrl &= (~(E1000_CTRL_TFCE | E1000_CTRL_RFCE));
866 		break;
867 	case e1000_fc_rx_pause:
868 		ctrl &= (~E1000_CTRL_TFCE);
869 		ctrl |= E1000_CTRL_RFCE;
870 		break;
871 	case e1000_fc_tx_pause:
872 		ctrl &= (~E1000_CTRL_RFCE);
873 		ctrl |= E1000_CTRL_TFCE;
874 		break;
875 	case e1000_fc_full:
876 		ctrl |= (E1000_CTRL_TFCE | E1000_CTRL_RFCE);
877 		break;
878 	default:
879 		hw_dbg("Flow control param set incorrectly\n");
880 		ret_val = -E1000_ERR_CONFIG;
881 		goto out;
882 	}
883 
884 	wr32(E1000_CTRL, ctrl);
885 
886 out:
887 	return ret_val;
888 }
889 
890 /**
891  *  igb_config_fc_after_link_up - Configures flow control after link
892  *  @hw: pointer to the HW structure
893  *
894  *  Checks the status of auto-negotiation after link up to ensure that the
895  *  speed and duplex were not forced.  If the link needed to be forced, then
896  *  flow control needs to be forced also.  If auto-negotiation is enabled
897  *  and did not fail, then we configure flow control based on our link
898  *  partner.
899  **/
900 s32 igb_config_fc_after_link_up(struct e1000_hw *hw)
901 {
902 	struct e1000_mac_info *mac = &hw->mac;
903 	s32 ret_val = 0;
904 	u32 pcs_status_reg, pcs_adv_reg, pcs_lp_ability_reg, pcs_ctrl_reg;
905 	u16 mii_status_reg, mii_nway_adv_reg, mii_nway_lp_ability_reg;
906 	u16 speed, duplex;
907 
908 	/* Check for the case where we have fiber media and auto-neg failed
909 	 * so we had to force link.  In this case, we need to force the
910 	 * configuration of the MAC to match the "fc" parameter.
911 	 */
912 	if (mac->autoneg_failed) {
913 		if (hw->phy.media_type == e1000_media_type_internal_serdes)
914 			ret_val = igb_force_mac_fc(hw);
915 	} else {
916 		if (hw->phy.media_type == e1000_media_type_copper)
917 			ret_val = igb_force_mac_fc(hw);
918 	}
919 
920 	if (ret_val) {
921 		hw_dbg("Error forcing flow control settings\n");
922 		goto out;
923 	}
924 
925 	/* Check for the case where we have copper media and auto-neg is
926 	 * enabled.  In this case, we need to check and see if Auto-Neg
927 	 * has completed, and if so, how the PHY and link partner has
928 	 * flow control configured.
929 	 */
930 	if ((hw->phy.media_type == e1000_media_type_copper) && mac->autoneg) {
931 		/* Read the MII Status Register and check to see if AutoNeg
932 		 * has completed.  We read this twice because this reg has
933 		 * some "sticky" (latched) bits.
934 		 */
935 		ret_val = hw->phy.ops.read_reg(hw, PHY_STATUS,
936 						   &mii_status_reg);
937 		if (ret_val)
938 			goto out;
939 		ret_val = hw->phy.ops.read_reg(hw, PHY_STATUS,
940 						   &mii_status_reg);
941 		if (ret_val)
942 			goto out;
943 
944 		if (!(mii_status_reg & MII_SR_AUTONEG_COMPLETE)) {
945 			hw_dbg("Copper PHY and Auto Neg has not completed.\n");
946 			goto out;
947 		}
948 
949 		/* The AutoNeg process has completed, so we now need to
950 		 * read both the Auto Negotiation Advertisement
951 		 * Register (Address 4) and the Auto_Negotiation Base
952 		 * Page Ability Register (Address 5) to determine how
953 		 * flow control was negotiated.
954 		 */
955 		ret_val = hw->phy.ops.read_reg(hw, PHY_AUTONEG_ADV,
956 					    &mii_nway_adv_reg);
957 		if (ret_val)
958 			goto out;
959 		ret_val = hw->phy.ops.read_reg(hw, PHY_LP_ABILITY,
960 					    &mii_nway_lp_ability_reg);
961 		if (ret_val)
962 			goto out;
963 
964 		/* Two bits in the Auto Negotiation Advertisement Register
965 		 * (Address 4) and two bits in the Auto Negotiation Base
966 		 * Page Ability Register (Address 5) determine flow control
967 		 * for both the PHY and the link partner.  The following
968 		 * table, taken out of the IEEE 802.3ab/D6.0 dated March 25,
969 		 * 1999, describes these PAUSE resolution bits and how flow
970 		 * control is determined based upon these settings.
971 		 * NOTE:  DC = Don't Care
972 		 *
973 		 *   LOCAL DEVICE  |   LINK PARTNER
974 		 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | NIC Resolution
975 		 *-------|---------|-------|---------|--------------------
976 		 *   0   |    0    |  DC   |   DC    | e1000_fc_none
977 		 *   0   |    1    |   0   |   DC    | e1000_fc_none
978 		 *   0   |    1    |   1   |    0    | e1000_fc_none
979 		 *   0   |    1    |   1   |    1    | e1000_fc_tx_pause
980 		 *   1   |    0    |   0   |   DC    | e1000_fc_none
981 		 *   1   |   DC    |   1   |   DC    | e1000_fc_full
982 		 *   1   |    1    |   0   |    0    | e1000_fc_none
983 		 *   1   |    1    |   0   |    1    | e1000_fc_rx_pause
984 		 *
985 		 * Are both PAUSE bits set to 1?  If so, this implies
986 		 * Symmetric Flow Control is enabled at both ends.  The
987 		 * ASM_DIR bits are irrelevant per the spec.
988 		 *
989 		 * For Symmetric Flow Control:
990 		 *
991 		 *   LOCAL DEVICE  |   LINK PARTNER
992 		 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
993 		 *-------|---------|-------|---------|--------------------
994 		 *   1   |   DC    |   1   |   DC    | E1000_fc_full
995 		 *
996 		 */
997 		if ((mii_nway_adv_reg & NWAY_AR_PAUSE) &&
998 		    (mii_nway_lp_ability_reg & NWAY_LPAR_PAUSE)) {
999 			/* Now we need to check if the user selected RX ONLY
1000 			 * of pause frames.  In this case, we had to advertise
1001 			 * FULL flow control because we could not advertise RX
1002 			 * ONLY. Hence, we must now check to see if we need to
1003 			 * turn OFF  the TRANSMISSION of PAUSE frames.
1004 			 */
1005 			if (hw->fc.requested_mode == e1000_fc_full) {
1006 				hw->fc.current_mode = e1000_fc_full;
1007 				hw_dbg("Flow Control = FULL.\n");
1008 			} else {
1009 				hw->fc.current_mode = e1000_fc_rx_pause;
1010 				hw_dbg("Flow Control = RX PAUSE frames only.\n");
1011 			}
1012 		}
1013 		/* For receiving PAUSE frames ONLY.
1014 		 *
1015 		 *   LOCAL DEVICE  |   LINK PARTNER
1016 		 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
1017 		 *-------|---------|-------|---------|--------------------
1018 		 *   0   |    1    |   1   |    1    | e1000_fc_tx_pause
1019 		 */
1020 		else if (!(mii_nway_adv_reg & NWAY_AR_PAUSE) &&
1021 			  (mii_nway_adv_reg & NWAY_AR_ASM_DIR) &&
1022 			  (mii_nway_lp_ability_reg & NWAY_LPAR_PAUSE) &&
1023 			  (mii_nway_lp_ability_reg & NWAY_LPAR_ASM_DIR)) {
1024 			hw->fc.current_mode = e1000_fc_tx_pause;
1025 			hw_dbg("Flow Control = TX PAUSE frames only.\n");
1026 		}
1027 		/* For transmitting PAUSE frames ONLY.
1028 		 *
1029 		 *   LOCAL DEVICE  |   LINK PARTNER
1030 		 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
1031 		 *-------|---------|-------|---------|--------------------
1032 		 *   1   |    1    |   0   |    1    | e1000_fc_rx_pause
1033 		 */
1034 		else if ((mii_nway_adv_reg & NWAY_AR_PAUSE) &&
1035 			 (mii_nway_adv_reg & NWAY_AR_ASM_DIR) &&
1036 			 !(mii_nway_lp_ability_reg & NWAY_LPAR_PAUSE) &&
1037 			 (mii_nway_lp_ability_reg & NWAY_LPAR_ASM_DIR)) {
1038 			hw->fc.current_mode = e1000_fc_rx_pause;
1039 			hw_dbg("Flow Control = RX PAUSE frames only.\n");
1040 		}
1041 		/* Per the IEEE spec, at this point flow control should be
1042 		 * disabled.  However, we want to consider that we could
1043 		 * be connected to a legacy switch that doesn't advertise
1044 		 * desired flow control, but can be forced on the link
1045 		 * partner.  So if we advertised no flow control, that is
1046 		 * what we will resolve to.  If we advertised some kind of
1047 		 * receive capability (Rx Pause Only or Full Flow Control)
1048 		 * and the link partner advertised none, we will configure
1049 		 * ourselves to enable Rx Flow Control only.  We can do
1050 		 * this safely for two reasons:  If the link partner really
1051 		 * didn't want flow control enabled, and we enable Rx, no
1052 		 * harm done since we won't be receiving any PAUSE frames
1053 		 * anyway.  If the intent on the link partner was to have
1054 		 * flow control enabled, then by us enabling RX only, we
1055 		 * can at least receive pause frames and process them.
1056 		 * This is a good idea because in most cases, since we are
1057 		 * predominantly a server NIC, more times than not we will
1058 		 * be asked to delay transmission of packets than asking
1059 		 * our link partner to pause transmission of frames.
1060 		 */
1061 		else if ((hw->fc.requested_mode == e1000_fc_none) ||
1062 			 (hw->fc.requested_mode == e1000_fc_tx_pause) ||
1063 			 (hw->fc.strict_ieee)) {
1064 			hw->fc.current_mode = e1000_fc_none;
1065 			hw_dbg("Flow Control = NONE.\n");
1066 		} else {
1067 			hw->fc.current_mode = e1000_fc_rx_pause;
1068 			hw_dbg("Flow Control = RX PAUSE frames only.\n");
1069 		}
1070 
1071 		/* Now we need to do one last check...  If we auto-
1072 		 * negotiated to HALF DUPLEX, flow control should not be
1073 		 * enabled per IEEE 802.3 spec.
1074 		 */
1075 		ret_val = hw->mac.ops.get_speed_and_duplex(hw, &speed, &duplex);
1076 		if (ret_val) {
1077 			hw_dbg("Error getting link speed and duplex\n");
1078 			goto out;
1079 		}
1080 
1081 		if (duplex == HALF_DUPLEX)
1082 			hw->fc.current_mode = e1000_fc_none;
1083 
1084 		/* Now we call a subroutine to actually force the MAC
1085 		 * controller to use the correct flow control settings.
1086 		 */
1087 		ret_val = igb_force_mac_fc(hw);
1088 		if (ret_val) {
1089 			hw_dbg("Error forcing flow control settings\n");
1090 			goto out;
1091 		}
1092 	}
1093 	/* Check for the case where we have SerDes media and auto-neg is
1094 	 * enabled.  In this case, we need to check and see if Auto-Neg
1095 	 * has completed, and if so, how the PHY and link partner has
1096 	 * flow control configured.
1097 	 */
1098 	if ((hw->phy.media_type == e1000_media_type_internal_serdes)
1099 		&& mac->autoneg) {
1100 		/* Read the PCS_LSTS and check to see if AutoNeg
1101 		 * has completed.
1102 		 */
1103 		pcs_status_reg = rd32(E1000_PCS_LSTAT);
1104 
1105 		if (!(pcs_status_reg & E1000_PCS_LSTS_AN_COMPLETE)) {
1106 			hw_dbg("PCS Auto Neg has not completed.\n");
1107 			return ret_val;
1108 		}
1109 
1110 		/* The AutoNeg process has completed, so we now need to
1111 		 * read both the Auto Negotiation Advertisement
1112 		 * Register (PCS_ANADV) and the Auto_Negotiation Base
1113 		 * Page Ability Register (PCS_LPAB) to determine how
1114 		 * flow control was negotiated.
1115 		 */
1116 		pcs_adv_reg = rd32(E1000_PCS_ANADV);
1117 		pcs_lp_ability_reg = rd32(E1000_PCS_LPAB);
1118 
1119 		/* Two bits in the Auto Negotiation Advertisement Register
1120 		 * (PCS_ANADV) and two bits in the Auto Negotiation Base
1121 		 * Page Ability Register (PCS_LPAB) determine flow control
1122 		 * for both the PHY and the link partner.  The following
1123 		 * table, taken out of the IEEE 802.3ab/D6.0 dated March 25,
1124 		 * 1999, describes these PAUSE resolution bits and how flow
1125 		 * control is determined based upon these settings.
1126 		 * NOTE:  DC = Don't Care
1127 		 *
1128 		 *   LOCAL DEVICE  |   LINK PARTNER
1129 		 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | NIC Resolution
1130 		 *-------|---------|-------|---------|--------------------
1131 		 *   0   |    0    |  DC   |   DC    | e1000_fc_none
1132 		 *   0   |    1    |   0   |   DC    | e1000_fc_none
1133 		 *   0   |    1    |   1   |    0    | e1000_fc_none
1134 		 *   0   |    1    |   1   |    1    | e1000_fc_tx_pause
1135 		 *   1   |    0    |   0   |   DC    | e1000_fc_none
1136 		 *   1   |   DC    |   1   |   DC    | e1000_fc_full
1137 		 *   1   |    1    |   0   |    0    | e1000_fc_none
1138 		 *   1   |    1    |   0   |    1    | e1000_fc_rx_pause
1139 		 *
1140 		 * Are both PAUSE bits set to 1?  If so, this implies
1141 		 * Symmetric Flow Control is enabled at both ends.  The
1142 		 * ASM_DIR bits are irrelevant per the spec.
1143 		 *
1144 		 * For Symmetric Flow Control:
1145 		 *
1146 		 *   LOCAL DEVICE  |   LINK PARTNER
1147 		 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
1148 		 *-------|---------|-------|---------|--------------------
1149 		 *   1   |   DC    |   1   |   DC    | e1000_fc_full
1150 		 *
1151 		 */
1152 		if ((pcs_adv_reg & E1000_TXCW_PAUSE) &&
1153 		    (pcs_lp_ability_reg & E1000_TXCW_PAUSE)) {
1154 			/* Now we need to check if the user selected Rx ONLY
1155 			 * of pause frames.  In this case, we had to advertise
1156 			 * FULL flow control because we could not advertise Rx
1157 			 * ONLY. Hence, we must now check to see if we need to
1158 			 * turn OFF the TRANSMISSION of PAUSE frames.
1159 			 */
1160 			if (hw->fc.requested_mode == e1000_fc_full) {
1161 				hw->fc.current_mode = e1000_fc_full;
1162 				hw_dbg("Flow Control = FULL.\n");
1163 			} else {
1164 				hw->fc.current_mode = e1000_fc_rx_pause;
1165 				hw_dbg("Flow Control = Rx PAUSE frames only.\n");
1166 			}
1167 		}
1168 		/* For receiving PAUSE frames ONLY.
1169 		 *
1170 		 *   LOCAL DEVICE  |   LINK PARTNER
1171 		 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
1172 		 *-------|---------|-------|---------|--------------------
1173 		 *   0   |    1    |   1   |    1    | e1000_fc_tx_pause
1174 		 */
1175 		else if (!(pcs_adv_reg & E1000_TXCW_PAUSE) &&
1176 			  (pcs_adv_reg & E1000_TXCW_ASM_DIR) &&
1177 			  (pcs_lp_ability_reg & E1000_TXCW_PAUSE) &&
1178 			  (pcs_lp_ability_reg & E1000_TXCW_ASM_DIR)) {
1179 			hw->fc.current_mode = e1000_fc_tx_pause;
1180 			hw_dbg("Flow Control = Tx PAUSE frames only.\n");
1181 		}
1182 		/* For transmitting PAUSE frames ONLY.
1183 		 *
1184 		 *   LOCAL DEVICE  |   LINK PARTNER
1185 		 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
1186 		 *-------|---------|-------|---------|--------------------
1187 		 *   1   |    1    |   0   |    1    | e1000_fc_rx_pause
1188 		 */
1189 		else if ((pcs_adv_reg & E1000_TXCW_PAUSE) &&
1190 			 (pcs_adv_reg & E1000_TXCW_ASM_DIR) &&
1191 			 !(pcs_lp_ability_reg & E1000_TXCW_PAUSE) &&
1192 			 (pcs_lp_ability_reg & E1000_TXCW_ASM_DIR)) {
1193 			hw->fc.current_mode = e1000_fc_rx_pause;
1194 			hw_dbg("Flow Control = Rx PAUSE frames only.\n");
1195 		} else {
1196 			/* Per the IEEE spec, at this point flow control
1197 			 * should be disabled.
1198 			 */
1199 			hw->fc.current_mode = e1000_fc_none;
1200 			hw_dbg("Flow Control = NONE.\n");
1201 		}
1202 
1203 		/* Now we call a subroutine to actually force the MAC
1204 		 * controller to use the correct flow control settings.
1205 		 */
1206 		pcs_ctrl_reg = rd32(E1000_PCS_LCTL);
1207 		pcs_ctrl_reg |= E1000_PCS_LCTL_FORCE_FCTRL;
1208 		wr32(E1000_PCS_LCTL, pcs_ctrl_reg);
1209 
1210 		ret_val = igb_force_mac_fc(hw);
1211 		if (ret_val) {
1212 			hw_dbg("Error forcing flow control settings\n");
1213 			return ret_val;
1214 		}
1215 	}
1216 
1217 out:
1218 	return ret_val;
1219 }
1220 
1221 /**
1222  *  igb_get_speed_and_duplex_copper - Retrieve current speed/duplex
1223  *  @hw: pointer to the HW structure
1224  *  @speed: stores the current speed
1225  *  @duplex: stores the current duplex
1226  *
1227  *  Read the status register for the current speed/duplex and store the current
1228  *  speed and duplex for copper connections.
1229  **/
1230 s32 igb_get_speed_and_duplex_copper(struct e1000_hw *hw, u16 *speed,
1231 				      u16 *duplex)
1232 {
1233 	u32 status;
1234 
1235 	status = rd32(E1000_STATUS);
1236 	if (status & E1000_STATUS_SPEED_1000) {
1237 		*speed = SPEED_1000;
1238 		hw_dbg("1000 Mbs, ");
1239 	} else if (status & E1000_STATUS_SPEED_100) {
1240 		*speed = SPEED_100;
1241 		hw_dbg("100 Mbs, ");
1242 	} else {
1243 		*speed = SPEED_10;
1244 		hw_dbg("10 Mbs, ");
1245 	}
1246 
1247 	if (status & E1000_STATUS_FD) {
1248 		*duplex = FULL_DUPLEX;
1249 		hw_dbg("Full Duplex\n");
1250 	} else {
1251 		*duplex = HALF_DUPLEX;
1252 		hw_dbg("Half Duplex\n");
1253 	}
1254 
1255 	return 0;
1256 }
1257 
1258 /**
1259  *  igb_get_hw_semaphore - Acquire hardware semaphore
1260  *  @hw: pointer to the HW structure
1261  *
1262  *  Acquire the HW semaphore to access the PHY or NVM
1263  **/
1264 s32 igb_get_hw_semaphore(struct e1000_hw *hw)
1265 {
1266 	u32 swsm;
1267 	s32 ret_val = 0;
1268 	s32 timeout = hw->nvm.word_size + 1;
1269 	s32 i = 0;
1270 
1271 	/* Get the SW semaphore */
1272 	while (i < timeout) {
1273 		swsm = rd32(E1000_SWSM);
1274 		if (!(swsm & E1000_SWSM_SMBI))
1275 			break;
1276 
1277 		udelay(50);
1278 		i++;
1279 	}
1280 
1281 	if (i == timeout) {
1282 		hw_dbg("Driver can't access device - SMBI bit is set.\n");
1283 		ret_val = -E1000_ERR_NVM;
1284 		goto out;
1285 	}
1286 
1287 	/* Get the FW semaphore. */
1288 	for (i = 0; i < timeout; i++) {
1289 		swsm = rd32(E1000_SWSM);
1290 		wr32(E1000_SWSM, swsm | E1000_SWSM_SWESMBI);
1291 
1292 		/* Semaphore acquired if bit latched */
1293 		if (rd32(E1000_SWSM) & E1000_SWSM_SWESMBI)
1294 			break;
1295 
1296 		udelay(50);
1297 	}
1298 
1299 	if (i == timeout) {
1300 		/* Release semaphores */
1301 		igb_put_hw_semaphore(hw);
1302 		hw_dbg("Driver can't access the NVM\n");
1303 		ret_val = -E1000_ERR_NVM;
1304 		goto out;
1305 	}
1306 
1307 out:
1308 	return ret_val;
1309 }
1310 
1311 /**
1312  *  igb_put_hw_semaphore - Release hardware semaphore
1313  *  @hw: pointer to the HW structure
1314  *
1315  *  Release hardware semaphore used to access the PHY or NVM
1316  **/
1317 void igb_put_hw_semaphore(struct e1000_hw *hw)
1318 {
1319 	u32 swsm;
1320 
1321 	swsm = rd32(E1000_SWSM);
1322 
1323 	swsm &= ~(E1000_SWSM_SMBI | E1000_SWSM_SWESMBI);
1324 
1325 	wr32(E1000_SWSM, swsm);
1326 }
1327 
1328 /**
1329  *  igb_get_auto_rd_done - Check for auto read completion
1330  *  @hw: pointer to the HW structure
1331  *
1332  *  Check EEPROM for Auto Read done bit.
1333  **/
1334 s32 igb_get_auto_rd_done(struct e1000_hw *hw)
1335 {
1336 	s32 i = 0;
1337 	s32 ret_val = 0;
1338 
1339 
1340 	while (i < AUTO_READ_DONE_TIMEOUT) {
1341 		if (rd32(E1000_EECD) & E1000_EECD_AUTO_RD)
1342 			break;
1343 		usleep_range(1000, 2000);
1344 		i++;
1345 	}
1346 
1347 	if (i == AUTO_READ_DONE_TIMEOUT) {
1348 		hw_dbg("Auto read by HW from NVM has not completed.\n");
1349 		ret_val = -E1000_ERR_RESET;
1350 		goto out;
1351 	}
1352 
1353 out:
1354 	return ret_val;
1355 }
1356 
1357 /**
1358  *  igb_valid_led_default - Verify a valid default LED config
1359  *  @hw: pointer to the HW structure
1360  *  @data: pointer to the NVM (EEPROM)
1361  *
1362  *  Read the EEPROM for the current default LED configuration.  If the
1363  *  LED configuration is not valid, set to a valid LED configuration.
1364  **/
1365 static s32 igb_valid_led_default(struct e1000_hw *hw, u16 *data)
1366 {
1367 	s32 ret_val;
1368 
1369 	ret_val = hw->nvm.ops.read(hw, NVM_ID_LED_SETTINGS, 1, data);
1370 	if (ret_val) {
1371 		hw_dbg("NVM Read Error\n");
1372 		goto out;
1373 	}
1374 
1375 	if (*data == ID_LED_RESERVED_0000 || *data == ID_LED_RESERVED_FFFF) {
1376 		switch (hw->phy.media_type) {
1377 		case e1000_media_type_internal_serdes:
1378 			*data = ID_LED_DEFAULT_82575_SERDES;
1379 			break;
1380 		case e1000_media_type_copper:
1381 		default:
1382 			*data = ID_LED_DEFAULT;
1383 			break;
1384 		}
1385 	}
1386 out:
1387 	return ret_val;
1388 }
1389 
1390 /**
1391  *  igb_id_led_init -
1392  *  @hw: pointer to the HW structure
1393  *
1394  **/
1395 s32 igb_id_led_init(struct e1000_hw *hw)
1396 {
1397 	struct e1000_mac_info *mac = &hw->mac;
1398 	s32 ret_val;
1399 	const u32 ledctl_mask = 0x000000FF;
1400 	const u32 ledctl_on = E1000_LEDCTL_MODE_LED_ON;
1401 	const u32 ledctl_off = E1000_LEDCTL_MODE_LED_OFF;
1402 	u16 data, i, temp;
1403 	const u16 led_mask = 0x0F;
1404 
1405 	/* i210 and i211 devices have different LED mechanism */
1406 	if ((hw->mac.type == e1000_i210) ||
1407 	    (hw->mac.type == e1000_i211))
1408 		ret_val = igb_valid_led_default_i210(hw, &data);
1409 	else
1410 		ret_val = igb_valid_led_default(hw, &data);
1411 
1412 	if (ret_val)
1413 		goto out;
1414 
1415 	mac->ledctl_default = rd32(E1000_LEDCTL);
1416 	mac->ledctl_mode1 = mac->ledctl_default;
1417 	mac->ledctl_mode2 = mac->ledctl_default;
1418 
1419 	for (i = 0; i < 4; i++) {
1420 		temp = (data >> (i << 2)) & led_mask;
1421 		switch (temp) {
1422 		case ID_LED_ON1_DEF2:
1423 		case ID_LED_ON1_ON2:
1424 		case ID_LED_ON1_OFF2:
1425 			mac->ledctl_mode1 &= ~(ledctl_mask << (i << 3));
1426 			mac->ledctl_mode1 |= ledctl_on << (i << 3);
1427 			break;
1428 		case ID_LED_OFF1_DEF2:
1429 		case ID_LED_OFF1_ON2:
1430 		case ID_LED_OFF1_OFF2:
1431 			mac->ledctl_mode1 &= ~(ledctl_mask << (i << 3));
1432 			mac->ledctl_mode1 |= ledctl_off << (i << 3);
1433 			break;
1434 		default:
1435 			/* Do nothing */
1436 			break;
1437 		}
1438 		switch (temp) {
1439 		case ID_LED_DEF1_ON2:
1440 		case ID_LED_ON1_ON2:
1441 		case ID_LED_OFF1_ON2:
1442 			mac->ledctl_mode2 &= ~(ledctl_mask << (i << 3));
1443 			mac->ledctl_mode2 |= ledctl_on << (i << 3);
1444 			break;
1445 		case ID_LED_DEF1_OFF2:
1446 		case ID_LED_ON1_OFF2:
1447 		case ID_LED_OFF1_OFF2:
1448 			mac->ledctl_mode2 &= ~(ledctl_mask << (i << 3));
1449 			mac->ledctl_mode2 |= ledctl_off << (i << 3);
1450 			break;
1451 		default:
1452 			/* Do nothing */
1453 			break;
1454 		}
1455 	}
1456 
1457 out:
1458 	return ret_val;
1459 }
1460 
1461 /**
1462  *  igb_cleanup_led - Set LED config to default operation
1463  *  @hw: pointer to the HW structure
1464  *
1465  *  Remove the current LED configuration and set the LED configuration
1466  *  to the default value, saved from the EEPROM.
1467  **/
1468 s32 igb_cleanup_led(struct e1000_hw *hw)
1469 {
1470 	wr32(E1000_LEDCTL, hw->mac.ledctl_default);
1471 	return 0;
1472 }
1473 
1474 /**
1475  *  igb_blink_led - Blink LED
1476  *  @hw: pointer to the HW structure
1477  *
1478  *  Blink the led's which are set to be on.
1479  **/
1480 s32 igb_blink_led(struct e1000_hw *hw)
1481 {
1482 	u32 ledctl_blink = 0;
1483 	u32 i;
1484 
1485 	if (hw->phy.media_type == e1000_media_type_fiber) {
1486 		/* always blink LED0 for PCI-E fiber */
1487 		ledctl_blink = E1000_LEDCTL_LED0_BLINK |
1488 		     (E1000_LEDCTL_MODE_LED_ON << E1000_LEDCTL_LED0_MODE_SHIFT);
1489 	} else {
1490 		/* Set the blink bit for each LED that's "on" (0x0E)
1491 		 * (or "off" if inverted) in ledctl_mode2.  The blink
1492 		 * logic in hardware only works when mode is set to "on"
1493 		 * so it must be changed accordingly when the mode is
1494 		 * "off" and inverted.
1495 		 */
1496 		ledctl_blink = hw->mac.ledctl_mode2;
1497 		for (i = 0; i < 32; i += 8) {
1498 			u32 mode = (hw->mac.ledctl_mode2 >> i) &
1499 			    E1000_LEDCTL_LED0_MODE_MASK;
1500 			u32 led_default = hw->mac.ledctl_default >> i;
1501 
1502 			if ((!(led_default & E1000_LEDCTL_LED0_IVRT) &&
1503 			     (mode == E1000_LEDCTL_MODE_LED_ON)) ||
1504 			    ((led_default & E1000_LEDCTL_LED0_IVRT) &&
1505 			     (mode == E1000_LEDCTL_MODE_LED_OFF))) {
1506 				ledctl_blink &=
1507 				    ~(E1000_LEDCTL_LED0_MODE_MASK << i);
1508 				ledctl_blink |= (E1000_LEDCTL_LED0_BLINK |
1509 						 E1000_LEDCTL_MODE_LED_ON) << i;
1510 			}
1511 		}
1512 	}
1513 
1514 	wr32(E1000_LEDCTL, ledctl_blink);
1515 
1516 	return 0;
1517 }
1518 
1519 /**
1520  *  igb_led_off - Turn LED off
1521  *  @hw: pointer to the HW structure
1522  *
1523  *  Turn LED off.
1524  **/
1525 s32 igb_led_off(struct e1000_hw *hw)
1526 {
1527 	switch (hw->phy.media_type) {
1528 	case e1000_media_type_copper:
1529 		wr32(E1000_LEDCTL, hw->mac.ledctl_mode1);
1530 		break;
1531 	default:
1532 		break;
1533 	}
1534 
1535 	return 0;
1536 }
1537 
1538 /**
1539  *  igb_disable_pcie_master - Disables PCI-express master access
1540  *  @hw: pointer to the HW structure
1541  *
1542  *  Returns 0 (0) if successful, else returns -10
1543  *  (-E1000_ERR_MASTER_REQUESTS_PENDING) if master disable bit has not caused
1544  *  the master requests to be disabled.
1545  *
1546  *  Disables PCI-Express master access and verifies there are no pending
1547  *  requests.
1548  **/
1549 s32 igb_disable_pcie_master(struct e1000_hw *hw)
1550 {
1551 	u32 ctrl;
1552 	s32 timeout = MASTER_DISABLE_TIMEOUT;
1553 	s32 ret_val = 0;
1554 
1555 	if (hw->bus.type != e1000_bus_type_pci_express)
1556 		goto out;
1557 
1558 	ctrl = rd32(E1000_CTRL);
1559 	ctrl |= E1000_CTRL_GIO_MASTER_DISABLE;
1560 	wr32(E1000_CTRL, ctrl);
1561 
1562 	while (timeout) {
1563 		if (!(rd32(E1000_STATUS) &
1564 		      E1000_STATUS_GIO_MASTER_ENABLE))
1565 			break;
1566 		udelay(100);
1567 		timeout--;
1568 	}
1569 
1570 	if (!timeout) {
1571 		hw_dbg("Master requests are pending.\n");
1572 		ret_val = -E1000_ERR_MASTER_REQUESTS_PENDING;
1573 		goto out;
1574 	}
1575 
1576 out:
1577 	return ret_val;
1578 }
1579 
1580 /**
1581  *  igb_validate_mdi_setting - Verify MDI/MDIx settings
1582  *  @hw: pointer to the HW structure
1583  *
1584  *  Verify that when not using auto-negotitation that MDI/MDIx is correctly
1585  *  set, which is forced to MDI mode only.
1586  **/
1587 s32 igb_validate_mdi_setting(struct e1000_hw *hw)
1588 {
1589 	s32 ret_val = 0;
1590 
1591 	/* All MDI settings are supported on 82580 and newer. */
1592 	if (hw->mac.type >= e1000_82580)
1593 		goto out;
1594 
1595 	if (!hw->mac.autoneg && (hw->phy.mdix == 0 || hw->phy.mdix == 3)) {
1596 		hw_dbg("Invalid MDI setting detected\n");
1597 		hw->phy.mdix = 1;
1598 		ret_val = -E1000_ERR_CONFIG;
1599 		goto out;
1600 	}
1601 
1602 out:
1603 	return ret_val;
1604 }
1605 
1606 /**
1607  *  igb_write_8bit_ctrl_reg - Write a 8bit CTRL register
1608  *  @hw: pointer to the HW structure
1609  *  @reg: 32bit register offset such as E1000_SCTL
1610  *  @offset: register offset to write to
1611  *  @data: data to write at register offset
1612  *
1613  *  Writes an address/data control type register.  There are several of these
1614  *  and they all have the format address << 8 | data and bit 31 is polled for
1615  *  completion.
1616  **/
1617 s32 igb_write_8bit_ctrl_reg(struct e1000_hw *hw, u32 reg,
1618 			      u32 offset, u8 data)
1619 {
1620 	u32 i, regvalue = 0;
1621 	s32 ret_val = 0;
1622 
1623 	/* Set up the address and data */
1624 	regvalue = ((u32)data) | (offset << E1000_GEN_CTL_ADDRESS_SHIFT);
1625 	wr32(reg, regvalue);
1626 
1627 	/* Poll the ready bit to see if the MDI read completed */
1628 	for (i = 0; i < E1000_GEN_POLL_TIMEOUT; i++) {
1629 		udelay(5);
1630 		regvalue = rd32(reg);
1631 		if (regvalue & E1000_GEN_CTL_READY)
1632 			break;
1633 	}
1634 	if (!(regvalue & E1000_GEN_CTL_READY)) {
1635 		hw_dbg("Reg %08x did not indicate ready\n", reg);
1636 		ret_val = -E1000_ERR_PHY;
1637 		goto out;
1638 	}
1639 
1640 out:
1641 	return ret_val;
1642 }
1643 
1644 /**
1645  *  igb_enable_mng_pass_thru - Enable processing of ARP's
1646  *  @hw: pointer to the HW structure
1647  *
1648  *  Verifies the hardware needs to leave interface enabled so that frames can
1649  *  be directed to and from the management interface.
1650  **/
1651 bool igb_enable_mng_pass_thru(struct e1000_hw *hw)
1652 {
1653 	u32 manc;
1654 	u32 fwsm, factps;
1655 	bool ret_val = false;
1656 
1657 	if (!hw->mac.asf_firmware_present)
1658 		goto out;
1659 
1660 	manc = rd32(E1000_MANC);
1661 
1662 	if (!(manc & E1000_MANC_RCV_TCO_EN))
1663 		goto out;
1664 
1665 	if (hw->mac.arc_subsystem_valid) {
1666 		fwsm = rd32(E1000_FWSM);
1667 		factps = rd32(E1000_FACTPS);
1668 
1669 		if (!(factps & E1000_FACTPS_MNGCG) &&
1670 		    ((fwsm & E1000_FWSM_MODE_MASK) ==
1671 		     (e1000_mng_mode_pt << E1000_FWSM_MODE_SHIFT))) {
1672 			ret_val = true;
1673 			goto out;
1674 		}
1675 	} else {
1676 		if ((manc & E1000_MANC_SMBUS_EN) &&
1677 		    !(manc & E1000_MANC_ASF_EN)) {
1678 			ret_val = true;
1679 			goto out;
1680 		}
1681 	}
1682 
1683 out:
1684 	return ret_val;
1685 }
1686