xref: /openbmc/linux/drivers/net/ethernet/intel/igb/e1000_mac.c (revision 5ef12cb4a3a78ffb331c03a795a15eea4ae35155)
1 // SPDX-License-Identifier: GPL-2.0
2 /* Intel(R) Gigabit Ethernet Linux driver
3  * Copyright(c) 2007-2014 Intel Corporation.
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms and conditions of the GNU General Public License,
7  * version 2, as published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12  * more details.
13  *
14  * You should have received a copy of the GNU General Public License along with
15  * this program; if not, see <http://www.gnu.org/licenses/>.
16  *
17  * The full GNU General Public License is included in this distribution in
18  * the file called "COPYING".
19  *
20  * Contact Information:
21  * e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
22  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
23  */
24 
25 #include <linux/if_ether.h>
26 #include <linux/delay.h>
27 #include <linux/pci.h>
28 #include <linux/netdevice.h>
29 #include <linux/etherdevice.h>
30 
31 #include "e1000_mac.h"
32 
33 #include "igb.h"
34 
35 static s32 igb_set_default_fc(struct e1000_hw *hw);
36 static s32 igb_set_fc_watermarks(struct e1000_hw *hw);
37 
38 /**
39  *  igb_get_bus_info_pcie - Get PCIe bus information
40  *  @hw: pointer to the HW structure
41  *
42  *  Determines and stores the system bus information for a particular
43  *  network interface.  The following bus information is determined and stored:
44  *  bus speed, bus width, type (PCIe), and PCIe function.
45  **/
46 s32 igb_get_bus_info_pcie(struct e1000_hw *hw)
47 {
48 	struct e1000_bus_info *bus = &hw->bus;
49 	s32 ret_val;
50 	u32 reg;
51 	u16 pcie_link_status;
52 
53 	bus->type = e1000_bus_type_pci_express;
54 
55 	ret_val = igb_read_pcie_cap_reg(hw,
56 					PCI_EXP_LNKSTA,
57 					&pcie_link_status);
58 	if (ret_val) {
59 		bus->width = e1000_bus_width_unknown;
60 		bus->speed = e1000_bus_speed_unknown;
61 	} else {
62 		switch (pcie_link_status & PCI_EXP_LNKSTA_CLS) {
63 		case PCI_EXP_LNKSTA_CLS_2_5GB:
64 			bus->speed = e1000_bus_speed_2500;
65 			break;
66 		case PCI_EXP_LNKSTA_CLS_5_0GB:
67 			bus->speed = e1000_bus_speed_5000;
68 			break;
69 		default:
70 			bus->speed = e1000_bus_speed_unknown;
71 			break;
72 		}
73 
74 		bus->width = (enum e1000_bus_width)((pcie_link_status &
75 						     PCI_EXP_LNKSTA_NLW) >>
76 						     PCI_EXP_LNKSTA_NLW_SHIFT);
77 	}
78 
79 	reg = rd32(E1000_STATUS);
80 	bus->func = (reg & E1000_STATUS_FUNC_MASK) >> E1000_STATUS_FUNC_SHIFT;
81 
82 	return 0;
83 }
84 
85 /**
86  *  igb_clear_vfta - Clear VLAN filter table
87  *  @hw: pointer to the HW structure
88  *
89  *  Clears the register array which contains the VLAN filter table by
90  *  setting all the values to 0.
91  **/
92 void igb_clear_vfta(struct e1000_hw *hw)
93 {
94 	u32 offset;
95 
96 	for (offset = E1000_VLAN_FILTER_TBL_SIZE; offset--;)
97 		hw->mac.ops.write_vfta(hw, offset, 0);
98 }
99 
100 /**
101  *  igb_write_vfta - Write value to VLAN filter table
102  *  @hw: pointer to the HW structure
103  *  @offset: register offset in VLAN filter table
104  *  @value: register value written to VLAN filter table
105  *
106  *  Writes value at the given offset in the register array which stores
107  *  the VLAN filter table.
108  **/
109 void igb_write_vfta(struct e1000_hw *hw, u32 offset, u32 value)
110 {
111 	struct igb_adapter *adapter = hw->back;
112 
113 	array_wr32(E1000_VFTA, offset, value);
114 	wrfl();
115 
116 	adapter->shadow_vfta[offset] = value;
117 }
118 
119 /**
120  *  igb_init_rx_addrs - Initialize receive address's
121  *  @hw: pointer to the HW structure
122  *  @rar_count: receive address registers
123  *
124  *  Setups the receive address registers by setting the base receive address
125  *  register to the devices MAC address and clearing all the other receive
126  *  address registers to 0.
127  **/
128 void igb_init_rx_addrs(struct e1000_hw *hw, u16 rar_count)
129 {
130 	u32 i;
131 	u8 mac_addr[ETH_ALEN] = {0};
132 
133 	/* Setup the receive address */
134 	hw_dbg("Programming MAC Address into RAR[0]\n");
135 
136 	hw->mac.ops.rar_set(hw, hw->mac.addr, 0);
137 
138 	/* Zero out the other (rar_entry_count - 1) receive addresses */
139 	hw_dbg("Clearing RAR[1-%u]\n", rar_count-1);
140 	for (i = 1; i < rar_count; i++)
141 		hw->mac.ops.rar_set(hw, mac_addr, i);
142 }
143 
144 /**
145  *  igb_find_vlvf_slot - find the VLAN id or the first empty slot
146  *  @hw: pointer to hardware structure
147  *  @vlan: VLAN id to write to VLAN filter
148  *  @vlvf_bypass: skip VLVF if no match is found
149  *
150  *  return the VLVF index where this VLAN id should be placed
151  *
152  **/
153 static s32 igb_find_vlvf_slot(struct e1000_hw *hw, u32 vlan, bool vlvf_bypass)
154 {
155 	s32 regindex, first_empty_slot;
156 	u32 bits;
157 
158 	/* short cut the special case */
159 	if (vlan == 0)
160 		return 0;
161 
162 	/* if vlvf_bypass is set we don't want to use an empty slot, we
163 	 * will simply bypass the VLVF if there are no entries present in the
164 	 * VLVF that contain our VLAN
165 	 */
166 	first_empty_slot = vlvf_bypass ? -E1000_ERR_NO_SPACE : 0;
167 
168 	/* Search for the VLAN id in the VLVF entries. Save off the first empty
169 	 * slot found along the way.
170 	 *
171 	 * pre-decrement loop covering (IXGBE_VLVF_ENTRIES - 1) .. 1
172 	 */
173 	for (regindex = E1000_VLVF_ARRAY_SIZE; --regindex > 0;) {
174 		bits = rd32(E1000_VLVF(regindex)) & E1000_VLVF_VLANID_MASK;
175 		if (bits == vlan)
176 			return regindex;
177 		if (!first_empty_slot && !bits)
178 			first_empty_slot = regindex;
179 	}
180 
181 	return first_empty_slot ? : -E1000_ERR_NO_SPACE;
182 }
183 
184 /**
185  *  igb_vfta_set - enable or disable vlan in VLAN filter table
186  *  @hw: pointer to the HW structure
187  *  @vlan: VLAN id to add or remove
188  *  @vind: VMDq output index that maps queue to VLAN id
189  *  @vlan_on: if true add filter, if false remove
190  *
191  *  Sets or clears a bit in the VLAN filter table array based on VLAN id
192  *  and if we are adding or removing the filter
193  **/
194 s32 igb_vfta_set(struct e1000_hw *hw, u32 vlan, u32 vind,
195 		 bool vlan_on, bool vlvf_bypass)
196 {
197 	struct igb_adapter *adapter = hw->back;
198 	u32 regidx, vfta_delta, vfta, bits;
199 	s32 vlvf_index;
200 
201 	if ((vlan > 4095) || (vind > 7))
202 		return -E1000_ERR_PARAM;
203 
204 	/* this is a 2 part operation - first the VFTA, then the
205 	 * VLVF and VLVFB if VT Mode is set
206 	 * We don't write the VFTA until we know the VLVF part succeeded.
207 	 */
208 
209 	/* Part 1
210 	 * The VFTA is a bitstring made up of 128 32-bit registers
211 	 * that enable the particular VLAN id, much like the MTA:
212 	 *    bits[11-5]: which register
213 	 *    bits[4-0]:  which bit in the register
214 	 */
215 	regidx = vlan / 32;
216 	vfta_delta = BIT(vlan % 32);
217 	vfta = adapter->shadow_vfta[regidx];
218 
219 	/* vfta_delta represents the difference between the current value
220 	 * of vfta and the value we want in the register.  Since the diff
221 	 * is an XOR mask we can just update vfta using an XOR.
222 	 */
223 	vfta_delta &= vlan_on ? ~vfta : vfta;
224 	vfta ^= vfta_delta;
225 
226 	/* Part 2
227 	 * If VT Mode is set
228 	 *   Either vlan_on
229 	 *     make sure the VLAN is in VLVF
230 	 *     set the vind bit in the matching VLVFB
231 	 *   Or !vlan_on
232 	 *     clear the pool bit and possibly the vind
233 	 */
234 	if (!adapter->vfs_allocated_count)
235 		goto vfta_update;
236 
237 	vlvf_index = igb_find_vlvf_slot(hw, vlan, vlvf_bypass);
238 	if (vlvf_index < 0) {
239 		if (vlvf_bypass)
240 			goto vfta_update;
241 		return vlvf_index;
242 	}
243 
244 	bits = rd32(E1000_VLVF(vlvf_index));
245 
246 	/* set the pool bit */
247 	bits |= BIT(E1000_VLVF_POOLSEL_SHIFT + vind);
248 	if (vlan_on)
249 		goto vlvf_update;
250 
251 	/* clear the pool bit */
252 	bits ^= BIT(E1000_VLVF_POOLSEL_SHIFT + vind);
253 
254 	if (!(bits & E1000_VLVF_POOLSEL_MASK)) {
255 		/* Clear VFTA first, then disable VLVF.  Otherwise
256 		 * we run the risk of stray packets leaking into
257 		 * the PF via the default pool
258 		 */
259 		if (vfta_delta)
260 			hw->mac.ops.write_vfta(hw, regidx, vfta);
261 
262 		/* disable VLVF and clear remaining bit from pool */
263 		wr32(E1000_VLVF(vlvf_index), 0);
264 
265 		return 0;
266 	}
267 
268 	/* If there are still bits set in the VLVFB registers
269 	 * for the VLAN ID indicated we need to see if the
270 	 * caller is requesting that we clear the VFTA entry bit.
271 	 * If the caller has requested that we clear the VFTA
272 	 * entry bit but there are still pools/VFs using this VLAN
273 	 * ID entry then ignore the request.  We're not worried
274 	 * about the case where we're turning the VFTA VLAN ID
275 	 * entry bit on, only when requested to turn it off as
276 	 * there may be multiple pools and/or VFs using the
277 	 * VLAN ID entry.  In that case we cannot clear the
278 	 * VFTA bit until all pools/VFs using that VLAN ID have also
279 	 * been cleared.  This will be indicated by "bits" being
280 	 * zero.
281 	 */
282 	vfta_delta = 0;
283 
284 vlvf_update:
285 	/* record pool change and enable VLAN ID if not already enabled */
286 	wr32(E1000_VLVF(vlvf_index), bits | vlan | E1000_VLVF_VLANID_ENABLE);
287 
288 vfta_update:
289 	/* bit was set/cleared before we started */
290 	if (vfta_delta)
291 		hw->mac.ops.write_vfta(hw, regidx, vfta);
292 
293 	return 0;
294 }
295 
296 /**
297  *  igb_check_alt_mac_addr - Check for alternate MAC addr
298  *  @hw: pointer to the HW structure
299  *
300  *  Checks the nvm for an alternate MAC address.  An alternate MAC address
301  *  can be setup by pre-boot software and must be treated like a permanent
302  *  address and must override the actual permanent MAC address.  If an
303  *  alternate MAC address is found it is saved in the hw struct and
304  *  programmed into RAR0 and the function returns success, otherwise the
305  *  function returns an error.
306  **/
307 s32 igb_check_alt_mac_addr(struct e1000_hw *hw)
308 {
309 	u32 i;
310 	s32 ret_val = 0;
311 	u16 offset, nvm_alt_mac_addr_offset, nvm_data;
312 	u8 alt_mac_addr[ETH_ALEN];
313 
314 	/* Alternate MAC address is handled by the option ROM for 82580
315 	 * and newer. SW support not required.
316 	 */
317 	if (hw->mac.type >= e1000_82580)
318 		goto out;
319 
320 	ret_val = hw->nvm.ops.read(hw, NVM_ALT_MAC_ADDR_PTR, 1,
321 				 &nvm_alt_mac_addr_offset);
322 	if (ret_val) {
323 		hw_dbg("NVM Read Error\n");
324 		goto out;
325 	}
326 
327 	if ((nvm_alt_mac_addr_offset == 0xFFFF) ||
328 	    (nvm_alt_mac_addr_offset == 0x0000))
329 		/* There is no Alternate MAC Address */
330 		goto out;
331 
332 	if (hw->bus.func == E1000_FUNC_1)
333 		nvm_alt_mac_addr_offset += E1000_ALT_MAC_ADDRESS_OFFSET_LAN1;
334 	if (hw->bus.func == E1000_FUNC_2)
335 		nvm_alt_mac_addr_offset += E1000_ALT_MAC_ADDRESS_OFFSET_LAN2;
336 
337 	if (hw->bus.func == E1000_FUNC_3)
338 		nvm_alt_mac_addr_offset += E1000_ALT_MAC_ADDRESS_OFFSET_LAN3;
339 	for (i = 0; i < ETH_ALEN; i += 2) {
340 		offset = nvm_alt_mac_addr_offset + (i >> 1);
341 		ret_val = hw->nvm.ops.read(hw, offset, 1, &nvm_data);
342 		if (ret_val) {
343 			hw_dbg("NVM Read Error\n");
344 			goto out;
345 		}
346 
347 		alt_mac_addr[i] = (u8)(nvm_data & 0xFF);
348 		alt_mac_addr[i + 1] = (u8)(nvm_data >> 8);
349 	}
350 
351 	/* if multicast bit is set, the alternate address will not be used */
352 	if (is_multicast_ether_addr(alt_mac_addr)) {
353 		hw_dbg("Ignoring Alternate Mac Address with MC bit set\n");
354 		goto out;
355 	}
356 
357 	/* We have a valid alternate MAC address, and we want to treat it the
358 	 * same as the normal permanent MAC address stored by the HW into the
359 	 * RAR. Do this by mapping this address into RAR0.
360 	 */
361 	hw->mac.ops.rar_set(hw, alt_mac_addr, 0);
362 
363 out:
364 	return ret_val;
365 }
366 
367 /**
368  *  igb_rar_set - Set receive address register
369  *  @hw: pointer to the HW structure
370  *  @addr: pointer to the receive address
371  *  @index: receive address array register
372  *
373  *  Sets the receive address array register at index to the address passed
374  *  in by addr.
375  **/
376 void igb_rar_set(struct e1000_hw *hw, u8 *addr, u32 index)
377 {
378 	u32 rar_low, rar_high;
379 
380 	/* HW expects these in little endian so we reverse the byte order
381 	 * from network order (big endian) to little endian
382 	 */
383 	rar_low = ((u32) addr[0] |
384 		   ((u32) addr[1] << 8) |
385 		    ((u32) addr[2] << 16) | ((u32) addr[3] << 24));
386 
387 	rar_high = ((u32) addr[4] | ((u32) addr[5] << 8));
388 
389 	/* If MAC address zero, no need to set the AV bit */
390 	if (rar_low || rar_high)
391 		rar_high |= E1000_RAH_AV;
392 
393 	/* Some bridges will combine consecutive 32-bit writes into
394 	 * a single burst write, which will malfunction on some parts.
395 	 * The flushes avoid this.
396 	 */
397 	wr32(E1000_RAL(index), rar_low);
398 	wrfl();
399 	wr32(E1000_RAH(index), rar_high);
400 	wrfl();
401 }
402 
403 /**
404  *  igb_mta_set - Set multicast filter table address
405  *  @hw: pointer to the HW structure
406  *  @hash_value: determines the MTA register and bit to set
407  *
408  *  The multicast table address is a register array of 32-bit registers.
409  *  The hash_value is used to determine what register the bit is in, the
410  *  current value is read, the new bit is OR'd in and the new value is
411  *  written back into the register.
412  **/
413 void igb_mta_set(struct e1000_hw *hw, u32 hash_value)
414 {
415 	u32 hash_bit, hash_reg, mta;
416 
417 	/* The MTA is a register array of 32-bit registers. It is
418 	 * treated like an array of (32*mta_reg_count) bits.  We want to
419 	 * set bit BitArray[hash_value]. So we figure out what register
420 	 * the bit is in, read it, OR in the new bit, then write
421 	 * back the new value.  The (hw->mac.mta_reg_count - 1) serves as a
422 	 * mask to bits 31:5 of the hash value which gives us the
423 	 * register we're modifying.  The hash bit within that register
424 	 * is determined by the lower 5 bits of the hash value.
425 	 */
426 	hash_reg = (hash_value >> 5) & (hw->mac.mta_reg_count - 1);
427 	hash_bit = hash_value & 0x1F;
428 
429 	mta = array_rd32(E1000_MTA, hash_reg);
430 
431 	mta |= BIT(hash_bit);
432 
433 	array_wr32(E1000_MTA, hash_reg, mta);
434 	wrfl();
435 }
436 
437 /**
438  *  igb_hash_mc_addr - Generate a multicast hash value
439  *  @hw: pointer to the HW structure
440  *  @mc_addr: pointer to a multicast address
441  *
442  *  Generates a multicast address hash value which is used to determine
443  *  the multicast filter table array address and new table value.  See
444  *  igb_mta_set()
445  **/
446 static u32 igb_hash_mc_addr(struct e1000_hw *hw, u8 *mc_addr)
447 {
448 	u32 hash_value, hash_mask;
449 	u8 bit_shift = 0;
450 
451 	/* Register count multiplied by bits per register */
452 	hash_mask = (hw->mac.mta_reg_count * 32) - 1;
453 
454 	/* For a mc_filter_type of 0, bit_shift is the number of left-shifts
455 	 * where 0xFF would still fall within the hash mask.
456 	 */
457 	while (hash_mask >> bit_shift != 0xFF)
458 		bit_shift++;
459 
460 	/* The portion of the address that is used for the hash table
461 	 * is determined by the mc_filter_type setting.
462 	 * The algorithm is such that there is a total of 8 bits of shifting.
463 	 * The bit_shift for a mc_filter_type of 0 represents the number of
464 	 * left-shifts where the MSB of mc_addr[5] would still fall within
465 	 * the hash_mask.  Case 0 does this exactly.  Since there are a total
466 	 * of 8 bits of shifting, then mc_addr[4] will shift right the
467 	 * remaining number of bits. Thus 8 - bit_shift.  The rest of the
468 	 * cases are a variation of this algorithm...essentially raising the
469 	 * number of bits to shift mc_addr[5] left, while still keeping the
470 	 * 8-bit shifting total.
471 	 *
472 	 * For example, given the following Destination MAC Address and an
473 	 * mta register count of 128 (thus a 4096-bit vector and 0xFFF mask),
474 	 * we can see that the bit_shift for case 0 is 4.  These are the hash
475 	 * values resulting from each mc_filter_type...
476 	 * [0] [1] [2] [3] [4] [5]
477 	 * 01  AA  00  12  34  56
478 	 * LSB                 MSB
479 	 *
480 	 * case 0: hash_value = ((0x34 >> 4) | (0x56 << 4)) & 0xFFF = 0x563
481 	 * case 1: hash_value = ((0x34 >> 3) | (0x56 << 5)) & 0xFFF = 0xAC6
482 	 * case 2: hash_value = ((0x34 >> 2) | (0x56 << 6)) & 0xFFF = 0x163
483 	 * case 3: hash_value = ((0x34 >> 0) | (0x56 << 8)) & 0xFFF = 0x634
484 	 */
485 	switch (hw->mac.mc_filter_type) {
486 	default:
487 	case 0:
488 		break;
489 	case 1:
490 		bit_shift += 1;
491 		break;
492 	case 2:
493 		bit_shift += 2;
494 		break;
495 	case 3:
496 		bit_shift += 4;
497 		break;
498 	}
499 
500 	hash_value = hash_mask & (((mc_addr[4] >> (8 - bit_shift)) |
501 				  (((u16) mc_addr[5]) << bit_shift)));
502 
503 	return hash_value;
504 }
505 
506 /**
507  *  igb_update_mc_addr_list - Update Multicast addresses
508  *  @hw: pointer to the HW structure
509  *  @mc_addr_list: array of multicast addresses to program
510  *  @mc_addr_count: number of multicast addresses to program
511  *
512  *  Updates entire Multicast Table Array.
513  *  The caller must have a packed mc_addr_list of multicast addresses.
514  **/
515 void igb_update_mc_addr_list(struct e1000_hw *hw,
516 			     u8 *mc_addr_list, u32 mc_addr_count)
517 {
518 	u32 hash_value, hash_bit, hash_reg;
519 	int i;
520 
521 	/* clear mta_shadow */
522 	memset(&hw->mac.mta_shadow, 0, sizeof(hw->mac.mta_shadow));
523 
524 	/* update mta_shadow from mc_addr_list */
525 	for (i = 0; (u32) i < mc_addr_count; i++) {
526 		hash_value = igb_hash_mc_addr(hw, mc_addr_list);
527 
528 		hash_reg = (hash_value >> 5) & (hw->mac.mta_reg_count - 1);
529 		hash_bit = hash_value & 0x1F;
530 
531 		hw->mac.mta_shadow[hash_reg] |= BIT(hash_bit);
532 		mc_addr_list += (ETH_ALEN);
533 	}
534 
535 	/* replace the entire MTA table */
536 	for (i = hw->mac.mta_reg_count - 1; i >= 0; i--)
537 		array_wr32(E1000_MTA, i, hw->mac.mta_shadow[i]);
538 	wrfl();
539 }
540 
541 /**
542  *  igb_clear_hw_cntrs_base - Clear base hardware counters
543  *  @hw: pointer to the HW structure
544  *
545  *  Clears the base hardware counters by reading the counter registers.
546  **/
547 void igb_clear_hw_cntrs_base(struct e1000_hw *hw)
548 {
549 	rd32(E1000_CRCERRS);
550 	rd32(E1000_SYMERRS);
551 	rd32(E1000_MPC);
552 	rd32(E1000_SCC);
553 	rd32(E1000_ECOL);
554 	rd32(E1000_MCC);
555 	rd32(E1000_LATECOL);
556 	rd32(E1000_COLC);
557 	rd32(E1000_DC);
558 	rd32(E1000_SEC);
559 	rd32(E1000_RLEC);
560 	rd32(E1000_XONRXC);
561 	rd32(E1000_XONTXC);
562 	rd32(E1000_XOFFRXC);
563 	rd32(E1000_XOFFTXC);
564 	rd32(E1000_FCRUC);
565 	rd32(E1000_GPRC);
566 	rd32(E1000_BPRC);
567 	rd32(E1000_MPRC);
568 	rd32(E1000_GPTC);
569 	rd32(E1000_GORCL);
570 	rd32(E1000_GORCH);
571 	rd32(E1000_GOTCL);
572 	rd32(E1000_GOTCH);
573 	rd32(E1000_RNBC);
574 	rd32(E1000_RUC);
575 	rd32(E1000_RFC);
576 	rd32(E1000_ROC);
577 	rd32(E1000_RJC);
578 	rd32(E1000_TORL);
579 	rd32(E1000_TORH);
580 	rd32(E1000_TOTL);
581 	rd32(E1000_TOTH);
582 	rd32(E1000_TPR);
583 	rd32(E1000_TPT);
584 	rd32(E1000_MPTC);
585 	rd32(E1000_BPTC);
586 }
587 
588 /**
589  *  igb_check_for_copper_link - Check for link (Copper)
590  *  @hw: pointer to the HW structure
591  *
592  *  Checks to see of the link status of the hardware has changed.  If a
593  *  change in link status has been detected, then we read the PHY registers
594  *  to get the current speed/duplex if link exists.
595  **/
596 s32 igb_check_for_copper_link(struct e1000_hw *hw)
597 {
598 	struct e1000_mac_info *mac = &hw->mac;
599 	s32 ret_val;
600 	bool link;
601 
602 	/* We only want to go out to the PHY registers to see if Auto-Neg
603 	 * has completed and/or if our link status has changed.  The
604 	 * get_link_status flag is set upon receiving a Link Status
605 	 * Change or Rx Sequence Error interrupt.
606 	 */
607 	if (!mac->get_link_status) {
608 		ret_val = 0;
609 		goto out;
610 	}
611 
612 	/* First we want to see if the MII Status Register reports
613 	 * link.  If so, then we want to get the current speed/duplex
614 	 * of the PHY.
615 	 */
616 	ret_val = igb_phy_has_link(hw, 1, 0, &link);
617 	if (ret_val)
618 		goto out;
619 
620 	if (!link)
621 		goto out; /* No link detected */
622 
623 	mac->get_link_status = false;
624 
625 	/* Check if there was DownShift, must be checked
626 	 * immediately after link-up
627 	 */
628 	igb_check_downshift(hw);
629 
630 	/* If we are forcing speed/duplex, then we simply return since
631 	 * we have already determined whether we have link or not.
632 	 */
633 	if (!mac->autoneg) {
634 		ret_val = -E1000_ERR_CONFIG;
635 		goto out;
636 	}
637 
638 	/* Auto-Neg is enabled.  Auto Speed Detection takes care
639 	 * of MAC speed/duplex configuration.  So we only need to
640 	 * configure Collision Distance in the MAC.
641 	 */
642 	igb_config_collision_dist(hw);
643 
644 	/* Configure Flow Control now that Auto-Neg has completed.
645 	 * First, we need to restore the desired flow control
646 	 * settings because we may have had to re-autoneg with a
647 	 * different link partner.
648 	 */
649 	ret_val = igb_config_fc_after_link_up(hw);
650 	if (ret_val)
651 		hw_dbg("Error configuring flow control\n");
652 
653 out:
654 	return ret_val;
655 }
656 
657 /**
658  *  igb_setup_link - Setup flow control and link settings
659  *  @hw: pointer to the HW structure
660  *
661  *  Determines which flow control settings to use, then configures flow
662  *  control.  Calls the appropriate media-specific link configuration
663  *  function.  Assuming the adapter has a valid link partner, a valid link
664  *  should be established.  Assumes the hardware has previously been reset
665  *  and the transmitter and receiver are not enabled.
666  **/
667 s32 igb_setup_link(struct e1000_hw *hw)
668 {
669 	s32 ret_val = 0;
670 
671 	/* In the case of the phy reset being blocked, we already have a link.
672 	 * We do not need to set it up again.
673 	 */
674 	if (igb_check_reset_block(hw))
675 		goto out;
676 
677 	/* If requested flow control is set to default, set flow control
678 	 * based on the EEPROM flow control settings.
679 	 */
680 	if (hw->fc.requested_mode == e1000_fc_default) {
681 		ret_val = igb_set_default_fc(hw);
682 		if (ret_val)
683 			goto out;
684 	}
685 
686 	/* We want to save off the original Flow Control configuration just
687 	 * in case we get disconnected and then reconnected into a different
688 	 * hub or switch with different Flow Control capabilities.
689 	 */
690 	hw->fc.current_mode = hw->fc.requested_mode;
691 
692 	hw_dbg("After fix-ups FlowControl is now = %x\n", hw->fc.current_mode);
693 
694 	/* Call the necessary media_type subroutine to configure the link. */
695 	ret_val = hw->mac.ops.setup_physical_interface(hw);
696 	if (ret_val)
697 		goto out;
698 
699 	/* Initialize the flow control address, type, and PAUSE timer
700 	 * registers to their default values.  This is done even if flow
701 	 * control is disabled, because it does not hurt anything to
702 	 * initialize these registers.
703 	 */
704 	hw_dbg("Initializing the Flow Control address, type and timer regs\n");
705 	wr32(E1000_FCT, FLOW_CONTROL_TYPE);
706 	wr32(E1000_FCAH, FLOW_CONTROL_ADDRESS_HIGH);
707 	wr32(E1000_FCAL, FLOW_CONTROL_ADDRESS_LOW);
708 
709 	wr32(E1000_FCTTV, hw->fc.pause_time);
710 
711 	ret_val = igb_set_fc_watermarks(hw);
712 
713 out:
714 
715 	return ret_val;
716 }
717 
718 /**
719  *  igb_config_collision_dist - Configure collision distance
720  *  @hw: pointer to the HW structure
721  *
722  *  Configures the collision distance to the default value and is used
723  *  during link setup. Currently no func pointer exists and all
724  *  implementations are handled in the generic version of this function.
725  **/
726 void igb_config_collision_dist(struct e1000_hw *hw)
727 {
728 	u32 tctl;
729 
730 	tctl = rd32(E1000_TCTL);
731 
732 	tctl &= ~E1000_TCTL_COLD;
733 	tctl |= E1000_COLLISION_DISTANCE << E1000_COLD_SHIFT;
734 
735 	wr32(E1000_TCTL, tctl);
736 	wrfl();
737 }
738 
739 /**
740  *  igb_set_fc_watermarks - Set flow control high/low watermarks
741  *  @hw: pointer to the HW structure
742  *
743  *  Sets the flow control high/low threshold (watermark) registers.  If
744  *  flow control XON frame transmission is enabled, then set XON frame
745  *  tansmission as well.
746  **/
747 static s32 igb_set_fc_watermarks(struct e1000_hw *hw)
748 {
749 	s32 ret_val = 0;
750 	u32 fcrtl = 0, fcrth = 0;
751 
752 	/* Set the flow control receive threshold registers.  Normally,
753 	 * these registers will be set to a default threshold that may be
754 	 * adjusted later by the driver's runtime code.  However, if the
755 	 * ability to transmit pause frames is not enabled, then these
756 	 * registers will be set to 0.
757 	 */
758 	if (hw->fc.current_mode & e1000_fc_tx_pause) {
759 		/* We need to set up the Receive Threshold high and low water
760 		 * marks as well as (optionally) enabling the transmission of
761 		 * XON frames.
762 		 */
763 		fcrtl = hw->fc.low_water;
764 		if (hw->fc.send_xon)
765 			fcrtl |= E1000_FCRTL_XONE;
766 
767 		fcrth = hw->fc.high_water;
768 	}
769 	wr32(E1000_FCRTL, fcrtl);
770 	wr32(E1000_FCRTH, fcrth);
771 
772 	return ret_val;
773 }
774 
775 /**
776  *  igb_set_default_fc - Set flow control default values
777  *  @hw: pointer to the HW structure
778  *
779  *  Read the EEPROM for the default values for flow control and store the
780  *  values.
781  **/
782 static s32 igb_set_default_fc(struct e1000_hw *hw)
783 {
784 	s32 ret_val = 0;
785 	u16 lan_offset;
786 	u16 nvm_data;
787 
788 	/* Read and store word 0x0F of the EEPROM. This word contains bits
789 	 * that determine the hardware's default PAUSE (flow control) mode,
790 	 * a bit that determines whether the HW defaults to enabling or
791 	 * disabling auto-negotiation, and the direction of the
792 	 * SW defined pins. If there is no SW over-ride of the flow
793 	 * control setting, then the variable hw->fc will
794 	 * be initialized based on a value in the EEPROM.
795 	 */
796 	if (hw->mac.type == e1000_i350)
797 		lan_offset = NVM_82580_LAN_FUNC_OFFSET(hw->bus.func);
798 	else
799 		lan_offset = 0;
800 
801 	ret_val = hw->nvm.ops.read(hw, NVM_INIT_CONTROL2_REG + lan_offset,
802 				   1, &nvm_data);
803 	if (ret_val) {
804 		hw_dbg("NVM Read Error\n");
805 		goto out;
806 	}
807 
808 	if ((nvm_data & NVM_WORD0F_PAUSE_MASK) == 0)
809 		hw->fc.requested_mode = e1000_fc_none;
810 	else if ((nvm_data & NVM_WORD0F_PAUSE_MASK) == NVM_WORD0F_ASM_DIR)
811 		hw->fc.requested_mode = e1000_fc_tx_pause;
812 	else
813 		hw->fc.requested_mode = e1000_fc_full;
814 
815 out:
816 	return ret_val;
817 }
818 
819 /**
820  *  igb_force_mac_fc - Force the MAC's flow control settings
821  *  @hw: pointer to the HW structure
822  *
823  *  Force the MAC's flow control settings.  Sets the TFCE and RFCE bits in the
824  *  device control register to reflect the adapter settings.  TFCE and RFCE
825  *  need to be explicitly set by software when a copper PHY is used because
826  *  autonegotiation is managed by the PHY rather than the MAC.  Software must
827  *  also configure these bits when link is forced on a fiber connection.
828  **/
829 s32 igb_force_mac_fc(struct e1000_hw *hw)
830 {
831 	u32 ctrl;
832 	s32 ret_val = 0;
833 
834 	ctrl = rd32(E1000_CTRL);
835 
836 	/* Because we didn't get link via the internal auto-negotiation
837 	 * mechanism (we either forced link or we got link via PHY
838 	 * auto-neg), we have to manually enable/disable transmit an
839 	 * receive flow control.
840 	 *
841 	 * The "Case" statement below enables/disable flow control
842 	 * according to the "hw->fc.current_mode" parameter.
843 	 *
844 	 * The possible values of the "fc" parameter are:
845 	 *      0:  Flow control is completely disabled
846 	 *      1:  Rx flow control is enabled (we can receive pause
847 	 *          frames but not send pause frames).
848 	 *      2:  Tx flow control is enabled (we can send pause frames
849 	 *          frames but we do not receive pause frames).
850 	 *      3:  Both Rx and TX flow control (symmetric) is enabled.
851 	 *  other:  No other values should be possible at this point.
852 	 */
853 	hw_dbg("hw->fc.current_mode = %u\n", hw->fc.current_mode);
854 
855 	switch (hw->fc.current_mode) {
856 	case e1000_fc_none:
857 		ctrl &= (~(E1000_CTRL_TFCE | E1000_CTRL_RFCE));
858 		break;
859 	case e1000_fc_rx_pause:
860 		ctrl &= (~E1000_CTRL_TFCE);
861 		ctrl |= E1000_CTRL_RFCE;
862 		break;
863 	case e1000_fc_tx_pause:
864 		ctrl &= (~E1000_CTRL_RFCE);
865 		ctrl |= E1000_CTRL_TFCE;
866 		break;
867 	case e1000_fc_full:
868 		ctrl |= (E1000_CTRL_TFCE | E1000_CTRL_RFCE);
869 		break;
870 	default:
871 		hw_dbg("Flow control param set incorrectly\n");
872 		ret_val = -E1000_ERR_CONFIG;
873 		goto out;
874 	}
875 
876 	wr32(E1000_CTRL, ctrl);
877 
878 out:
879 	return ret_val;
880 }
881 
882 /**
883  *  igb_config_fc_after_link_up - Configures flow control after link
884  *  @hw: pointer to the HW structure
885  *
886  *  Checks the status of auto-negotiation after link up to ensure that the
887  *  speed and duplex were not forced.  If the link needed to be forced, then
888  *  flow control needs to be forced also.  If auto-negotiation is enabled
889  *  and did not fail, then we configure flow control based on our link
890  *  partner.
891  **/
892 s32 igb_config_fc_after_link_up(struct e1000_hw *hw)
893 {
894 	struct e1000_mac_info *mac = &hw->mac;
895 	s32 ret_val = 0;
896 	u32 pcs_status_reg, pcs_adv_reg, pcs_lp_ability_reg, pcs_ctrl_reg;
897 	u16 mii_status_reg, mii_nway_adv_reg, mii_nway_lp_ability_reg;
898 	u16 speed, duplex;
899 
900 	/* Check for the case where we have fiber media and auto-neg failed
901 	 * so we had to force link.  In this case, we need to force the
902 	 * configuration of the MAC to match the "fc" parameter.
903 	 */
904 	if (mac->autoneg_failed) {
905 		if (hw->phy.media_type == e1000_media_type_internal_serdes)
906 			ret_val = igb_force_mac_fc(hw);
907 	} else {
908 		if (hw->phy.media_type == e1000_media_type_copper)
909 			ret_val = igb_force_mac_fc(hw);
910 	}
911 
912 	if (ret_val) {
913 		hw_dbg("Error forcing flow control settings\n");
914 		goto out;
915 	}
916 
917 	/* Check for the case where we have copper media and auto-neg is
918 	 * enabled.  In this case, we need to check and see if Auto-Neg
919 	 * has completed, and if so, how the PHY and link partner has
920 	 * flow control configured.
921 	 */
922 	if ((hw->phy.media_type == e1000_media_type_copper) && mac->autoneg) {
923 		/* Read the MII Status Register and check to see if AutoNeg
924 		 * has completed.  We read this twice because this reg has
925 		 * some "sticky" (latched) bits.
926 		 */
927 		ret_val = hw->phy.ops.read_reg(hw, PHY_STATUS,
928 						   &mii_status_reg);
929 		if (ret_val)
930 			goto out;
931 		ret_val = hw->phy.ops.read_reg(hw, PHY_STATUS,
932 						   &mii_status_reg);
933 		if (ret_val)
934 			goto out;
935 
936 		if (!(mii_status_reg & MII_SR_AUTONEG_COMPLETE)) {
937 			hw_dbg("Copper PHY and Auto Neg has not completed.\n");
938 			goto out;
939 		}
940 
941 		/* The AutoNeg process has completed, so we now need to
942 		 * read both the Auto Negotiation Advertisement
943 		 * Register (Address 4) and the Auto_Negotiation Base
944 		 * Page Ability Register (Address 5) to determine how
945 		 * flow control was negotiated.
946 		 */
947 		ret_val = hw->phy.ops.read_reg(hw, PHY_AUTONEG_ADV,
948 					    &mii_nway_adv_reg);
949 		if (ret_val)
950 			goto out;
951 		ret_val = hw->phy.ops.read_reg(hw, PHY_LP_ABILITY,
952 					    &mii_nway_lp_ability_reg);
953 		if (ret_val)
954 			goto out;
955 
956 		/* Two bits in the Auto Negotiation Advertisement Register
957 		 * (Address 4) and two bits in the Auto Negotiation Base
958 		 * Page Ability Register (Address 5) determine flow control
959 		 * for both the PHY and the link partner.  The following
960 		 * table, taken out of the IEEE 802.3ab/D6.0 dated March 25,
961 		 * 1999, describes these PAUSE resolution bits and how flow
962 		 * control is determined based upon these settings.
963 		 * NOTE:  DC = Don't Care
964 		 *
965 		 *   LOCAL DEVICE  |   LINK PARTNER
966 		 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | NIC Resolution
967 		 *-------|---------|-------|---------|--------------------
968 		 *   0   |    0    |  DC   |   DC    | e1000_fc_none
969 		 *   0   |    1    |   0   |   DC    | e1000_fc_none
970 		 *   0   |    1    |   1   |    0    | e1000_fc_none
971 		 *   0   |    1    |   1   |    1    | e1000_fc_tx_pause
972 		 *   1   |    0    |   0   |   DC    | e1000_fc_none
973 		 *   1   |   DC    |   1   |   DC    | e1000_fc_full
974 		 *   1   |    1    |   0   |    0    | e1000_fc_none
975 		 *   1   |    1    |   0   |    1    | e1000_fc_rx_pause
976 		 *
977 		 * Are both PAUSE bits set to 1?  If so, this implies
978 		 * Symmetric Flow Control is enabled at both ends.  The
979 		 * ASM_DIR bits are irrelevant per the spec.
980 		 *
981 		 * For Symmetric Flow Control:
982 		 *
983 		 *   LOCAL DEVICE  |   LINK PARTNER
984 		 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
985 		 *-------|---------|-------|---------|--------------------
986 		 *   1   |   DC    |   1   |   DC    | E1000_fc_full
987 		 *
988 		 */
989 		if ((mii_nway_adv_reg & NWAY_AR_PAUSE) &&
990 		    (mii_nway_lp_ability_reg & NWAY_LPAR_PAUSE)) {
991 			/* Now we need to check if the user selected RX ONLY
992 			 * of pause frames.  In this case, we had to advertise
993 			 * FULL flow control because we could not advertise RX
994 			 * ONLY. Hence, we must now check to see if we need to
995 			 * turn OFF  the TRANSMISSION of PAUSE frames.
996 			 */
997 			if (hw->fc.requested_mode == e1000_fc_full) {
998 				hw->fc.current_mode = e1000_fc_full;
999 				hw_dbg("Flow Control = FULL.\n");
1000 			} else {
1001 				hw->fc.current_mode = e1000_fc_rx_pause;
1002 				hw_dbg("Flow Control = RX PAUSE frames only.\n");
1003 			}
1004 		}
1005 		/* For receiving PAUSE frames ONLY.
1006 		 *
1007 		 *   LOCAL DEVICE  |   LINK PARTNER
1008 		 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
1009 		 *-------|---------|-------|---------|--------------------
1010 		 *   0   |    1    |   1   |    1    | e1000_fc_tx_pause
1011 		 */
1012 		else if (!(mii_nway_adv_reg & NWAY_AR_PAUSE) &&
1013 			  (mii_nway_adv_reg & NWAY_AR_ASM_DIR) &&
1014 			  (mii_nway_lp_ability_reg & NWAY_LPAR_PAUSE) &&
1015 			  (mii_nway_lp_ability_reg & NWAY_LPAR_ASM_DIR)) {
1016 			hw->fc.current_mode = e1000_fc_tx_pause;
1017 			hw_dbg("Flow Control = TX PAUSE frames only.\n");
1018 		}
1019 		/* For transmitting PAUSE frames ONLY.
1020 		 *
1021 		 *   LOCAL DEVICE  |   LINK PARTNER
1022 		 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
1023 		 *-------|---------|-------|---------|--------------------
1024 		 *   1   |    1    |   0   |    1    | e1000_fc_rx_pause
1025 		 */
1026 		else if ((mii_nway_adv_reg & NWAY_AR_PAUSE) &&
1027 			 (mii_nway_adv_reg & NWAY_AR_ASM_DIR) &&
1028 			 !(mii_nway_lp_ability_reg & NWAY_LPAR_PAUSE) &&
1029 			 (mii_nway_lp_ability_reg & NWAY_LPAR_ASM_DIR)) {
1030 			hw->fc.current_mode = e1000_fc_rx_pause;
1031 			hw_dbg("Flow Control = RX PAUSE frames only.\n");
1032 		}
1033 		/* Per the IEEE spec, at this point flow control should be
1034 		 * disabled.  However, we want to consider that we could
1035 		 * be connected to a legacy switch that doesn't advertise
1036 		 * desired flow control, but can be forced on the link
1037 		 * partner.  So if we advertised no flow control, that is
1038 		 * what we will resolve to.  If we advertised some kind of
1039 		 * receive capability (Rx Pause Only or Full Flow Control)
1040 		 * and the link partner advertised none, we will configure
1041 		 * ourselves to enable Rx Flow Control only.  We can do
1042 		 * this safely for two reasons:  If the link partner really
1043 		 * didn't want flow control enabled, and we enable Rx, no
1044 		 * harm done since we won't be receiving any PAUSE frames
1045 		 * anyway.  If the intent on the link partner was to have
1046 		 * flow control enabled, then by us enabling RX only, we
1047 		 * can at least receive pause frames and process them.
1048 		 * This is a good idea because in most cases, since we are
1049 		 * predominantly a server NIC, more times than not we will
1050 		 * be asked to delay transmission of packets than asking
1051 		 * our link partner to pause transmission of frames.
1052 		 */
1053 		else if ((hw->fc.requested_mode == e1000_fc_none) ||
1054 			 (hw->fc.requested_mode == e1000_fc_tx_pause) ||
1055 			 (hw->fc.strict_ieee)) {
1056 			hw->fc.current_mode = e1000_fc_none;
1057 			hw_dbg("Flow Control = NONE.\n");
1058 		} else {
1059 			hw->fc.current_mode = e1000_fc_rx_pause;
1060 			hw_dbg("Flow Control = RX PAUSE frames only.\n");
1061 		}
1062 
1063 		/* Now we need to do one last check...  If we auto-
1064 		 * negotiated to HALF DUPLEX, flow control should not be
1065 		 * enabled per IEEE 802.3 spec.
1066 		 */
1067 		ret_val = hw->mac.ops.get_speed_and_duplex(hw, &speed, &duplex);
1068 		if (ret_val) {
1069 			hw_dbg("Error getting link speed and duplex\n");
1070 			goto out;
1071 		}
1072 
1073 		if (duplex == HALF_DUPLEX)
1074 			hw->fc.current_mode = e1000_fc_none;
1075 
1076 		/* Now we call a subroutine to actually force the MAC
1077 		 * controller to use the correct flow control settings.
1078 		 */
1079 		ret_val = igb_force_mac_fc(hw);
1080 		if (ret_val) {
1081 			hw_dbg("Error forcing flow control settings\n");
1082 			goto out;
1083 		}
1084 	}
1085 	/* Check for the case where we have SerDes media and auto-neg is
1086 	 * enabled.  In this case, we need to check and see if Auto-Neg
1087 	 * has completed, and if so, how the PHY and link partner has
1088 	 * flow control configured.
1089 	 */
1090 	if ((hw->phy.media_type == e1000_media_type_internal_serdes)
1091 		&& mac->autoneg) {
1092 		/* Read the PCS_LSTS and check to see if AutoNeg
1093 		 * has completed.
1094 		 */
1095 		pcs_status_reg = rd32(E1000_PCS_LSTAT);
1096 
1097 		if (!(pcs_status_reg & E1000_PCS_LSTS_AN_COMPLETE)) {
1098 			hw_dbg("PCS Auto Neg has not completed.\n");
1099 			return ret_val;
1100 		}
1101 
1102 		/* The AutoNeg process has completed, so we now need to
1103 		 * read both the Auto Negotiation Advertisement
1104 		 * Register (PCS_ANADV) and the Auto_Negotiation Base
1105 		 * Page Ability Register (PCS_LPAB) to determine how
1106 		 * flow control was negotiated.
1107 		 */
1108 		pcs_adv_reg = rd32(E1000_PCS_ANADV);
1109 		pcs_lp_ability_reg = rd32(E1000_PCS_LPAB);
1110 
1111 		/* Two bits in the Auto Negotiation Advertisement Register
1112 		 * (PCS_ANADV) and two bits in the Auto Negotiation Base
1113 		 * Page Ability Register (PCS_LPAB) determine flow control
1114 		 * for both the PHY and the link partner.  The following
1115 		 * table, taken out of the IEEE 802.3ab/D6.0 dated March 25,
1116 		 * 1999, describes these PAUSE resolution bits and how flow
1117 		 * control is determined based upon these settings.
1118 		 * NOTE:  DC = Don't Care
1119 		 *
1120 		 *   LOCAL DEVICE  |   LINK PARTNER
1121 		 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | NIC Resolution
1122 		 *-------|---------|-------|---------|--------------------
1123 		 *   0   |    0    |  DC   |   DC    | e1000_fc_none
1124 		 *   0   |    1    |   0   |   DC    | e1000_fc_none
1125 		 *   0   |    1    |   1   |    0    | e1000_fc_none
1126 		 *   0   |    1    |   1   |    1    | e1000_fc_tx_pause
1127 		 *   1   |    0    |   0   |   DC    | e1000_fc_none
1128 		 *   1   |   DC    |   1   |   DC    | e1000_fc_full
1129 		 *   1   |    1    |   0   |    0    | e1000_fc_none
1130 		 *   1   |    1    |   0   |    1    | e1000_fc_rx_pause
1131 		 *
1132 		 * Are both PAUSE bits set to 1?  If so, this implies
1133 		 * Symmetric Flow Control is enabled at both ends.  The
1134 		 * ASM_DIR bits are irrelevant per the spec.
1135 		 *
1136 		 * For Symmetric Flow Control:
1137 		 *
1138 		 *   LOCAL DEVICE  |   LINK PARTNER
1139 		 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
1140 		 *-------|---------|-------|---------|--------------------
1141 		 *   1   |   DC    |   1   |   DC    | e1000_fc_full
1142 		 *
1143 		 */
1144 		if ((pcs_adv_reg & E1000_TXCW_PAUSE) &&
1145 		    (pcs_lp_ability_reg & E1000_TXCW_PAUSE)) {
1146 			/* Now we need to check if the user selected Rx ONLY
1147 			 * of pause frames.  In this case, we had to advertise
1148 			 * FULL flow control because we could not advertise Rx
1149 			 * ONLY. Hence, we must now check to see if we need to
1150 			 * turn OFF the TRANSMISSION of PAUSE frames.
1151 			 */
1152 			if (hw->fc.requested_mode == e1000_fc_full) {
1153 				hw->fc.current_mode = e1000_fc_full;
1154 				hw_dbg("Flow Control = FULL.\n");
1155 			} else {
1156 				hw->fc.current_mode = e1000_fc_rx_pause;
1157 				hw_dbg("Flow Control = Rx PAUSE frames only.\n");
1158 			}
1159 		}
1160 		/* For receiving PAUSE frames ONLY.
1161 		 *
1162 		 *   LOCAL DEVICE  |   LINK PARTNER
1163 		 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
1164 		 *-------|---------|-------|---------|--------------------
1165 		 *   0   |    1    |   1   |    1    | e1000_fc_tx_pause
1166 		 */
1167 		else if (!(pcs_adv_reg & E1000_TXCW_PAUSE) &&
1168 			  (pcs_adv_reg & E1000_TXCW_ASM_DIR) &&
1169 			  (pcs_lp_ability_reg & E1000_TXCW_PAUSE) &&
1170 			  (pcs_lp_ability_reg & E1000_TXCW_ASM_DIR)) {
1171 			hw->fc.current_mode = e1000_fc_tx_pause;
1172 			hw_dbg("Flow Control = Tx PAUSE frames only.\n");
1173 		}
1174 		/* For transmitting PAUSE frames ONLY.
1175 		 *
1176 		 *   LOCAL DEVICE  |   LINK PARTNER
1177 		 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
1178 		 *-------|---------|-------|---------|--------------------
1179 		 *   1   |    1    |   0   |    1    | e1000_fc_rx_pause
1180 		 */
1181 		else if ((pcs_adv_reg & E1000_TXCW_PAUSE) &&
1182 			 (pcs_adv_reg & E1000_TXCW_ASM_DIR) &&
1183 			 !(pcs_lp_ability_reg & E1000_TXCW_PAUSE) &&
1184 			 (pcs_lp_ability_reg & E1000_TXCW_ASM_DIR)) {
1185 			hw->fc.current_mode = e1000_fc_rx_pause;
1186 			hw_dbg("Flow Control = Rx PAUSE frames only.\n");
1187 		} else {
1188 			/* Per the IEEE spec, at this point flow control
1189 			 * should be disabled.
1190 			 */
1191 			hw->fc.current_mode = e1000_fc_none;
1192 			hw_dbg("Flow Control = NONE.\n");
1193 		}
1194 
1195 		/* Now we call a subroutine to actually force the MAC
1196 		 * controller to use the correct flow control settings.
1197 		 */
1198 		pcs_ctrl_reg = rd32(E1000_PCS_LCTL);
1199 		pcs_ctrl_reg |= E1000_PCS_LCTL_FORCE_FCTRL;
1200 		wr32(E1000_PCS_LCTL, pcs_ctrl_reg);
1201 
1202 		ret_val = igb_force_mac_fc(hw);
1203 		if (ret_val) {
1204 			hw_dbg("Error forcing flow control settings\n");
1205 			return ret_val;
1206 		}
1207 	}
1208 
1209 out:
1210 	return ret_val;
1211 }
1212 
1213 /**
1214  *  igb_get_speed_and_duplex_copper - Retrieve current speed/duplex
1215  *  @hw: pointer to the HW structure
1216  *  @speed: stores the current speed
1217  *  @duplex: stores the current duplex
1218  *
1219  *  Read the status register for the current speed/duplex and store the current
1220  *  speed and duplex for copper connections.
1221  **/
1222 s32 igb_get_speed_and_duplex_copper(struct e1000_hw *hw, u16 *speed,
1223 				      u16 *duplex)
1224 {
1225 	u32 status;
1226 
1227 	status = rd32(E1000_STATUS);
1228 	if (status & E1000_STATUS_SPEED_1000) {
1229 		*speed = SPEED_1000;
1230 		hw_dbg("1000 Mbs, ");
1231 	} else if (status & E1000_STATUS_SPEED_100) {
1232 		*speed = SPEED_100;
1233 		hw_dbg("100 Mbs, ");
1234 	} else {
1235 		*speed = SPEED_10;
1236 		hw_dbg("10 Mbs, ");
1237 	}
1238 
1239 	if (status & E1000_STATUS_FD) {
1240 		*duplex = FULL_DUPLEX;
1241 		hw_dbg("Full Duplex\n");
1242 	} else {
1243 		*duplex = HALF_DUPLEX;
1244 		hw_dbg("Half Duplex\n");
1245 	}
1246 
1247 	return 0;
1248 }
1249 
1250 /**
1251  *  igb_get_hw_semaphore - Acquire hardware semaphore
1252  *  @hw: pointer to the HW structure
1253  *
1254  *  Acquire the HW semaphore to access the PHY or NVM
1255  **/
1256 s32 igb_get_hw_semaphore(struct e1000_hw *hw)
1257 {
1258 	u32 swsm;
1259 	s32 ret_val = 0;
1260 	s32 timeout = hw->nvm.word_size + 1;
1261 	s32 i = 0;
1262 
1263 	/* Get the SW semaphore */
1264 	while (i < timeout) {
1265 		swsm = rd32(E1000_SWSM);
1266 		if (!(swsm & E1000_SWSM_SMBI))
1267 			break;
1268 
1269 		udelay(50);
1270 		i++;
1271 	}
1272 
1273 	if (i == timeout) {
1274 		hw_dbg("Driver can't access device - SMBI bit is set.\n");
1275 		ret_val = -E1000_ERR_NVM;
1276 		goto out;
1277 	}
1278 
1279 	/* Get the FW semaphore. */
1280 	for (i = 0; i < timeout; i++) {
1281 		swsm = rd32(E1000_SWSM);
1282 		wr32(E1000_SWSM, swsm | E1000_SWSM_SWESMBI);
1283 
1284 		/* Semaphore acquired if bit latched */
1285 		if (rd32(E1000_SWSM) & E1000_SWSM_SWESMBI)
1286 			break;
1287 
1288 		udelay(50);
1289 	}
1290 
1291 	if (i == timeout) {
1292 		/* Release semaphores */
1293 		igb_put_hw_semaphore(hw);
1294 		hw_dbg("Driver can't access the NVM\n");
1295 		ret_val = -E1000_ERR_NVM;
1296 		goto out;
1297 	}
1298 
1299 out:
1300 	return ret_val;
1301 }
1302 
1303 /**
1304  *  igb_put_hw_semaphore - Release hardware semaphore
1305  *  @hw: pointer to the HW structure
1306  *
1307  *  Release hardware semaphore used to access the PHY or NVM
1308  **/
1309 void igb_put_hw_semaphore(struct e1000_hw *hw)
1310 {
1311 	u32 swsm;
1312 
1313 	swsm = rd32(E1000_SWSM);
1314 
1315 	swsm &= ~(E1000_SWSM_SMBI | E1000_SWSM_SWESMBI);
1316 
1317 	wr32(E1000_SWSM, swsm);
1318 }
1319 
1320 /**
1321  *  igb_get_auto_rd_done - Check for auto read completion
1322  *  @hw: pointer to the HW structure
1323  *
1324  *  Check EEPROM for Auto Read done bit.
1325  **/
1326 s32 igb_get_auto_rd_done(struct e1000_hw *hw)
1327 {
1328 	s32 i = 0;
1329 	s32 ret_val = 0;
1330 
1331 
1332 	while (i < AUTO_READ_DONE_TIMEOUT) {
1333 		if (rd32(E1000_EECD) & E1000_EECD_AUTO_RD)
1334 			break;
1335 		usleep_range(1000, 2000);
1336 		i++;
1337 	}
1338 
1339 	if (i == AUTO_READ_DONE_TIMEOUT) {
1340 		hw_dbg("Auto read by HW from NVM has not completed.\n");
1341 		ret_val = -E1000_ERR_RESET;
1342 		goto out;
1343 	}
1344 
1345 out:
1346 	return ret_val;
1347 }
1348 
1349 /**
1350  *  igb_valid_led_default - Verify a valid default LED config
1351  *  @hw: pointer to the HW structure
1352  *  @data: pointer to the NVM (EEPROM)
1353  *
1354  *  Read the EEPROM for the current default LED configuration.  If the
1355  *  LED configuration is not valid, set to a valid LED configuration.
1356  **/
1357 static s32 igb_valid_led_default(struct e1000_hw *hw, u16 *data)
1358 {
1359 	s32 ret_val;
1360 
1361 	ret_val = hw->nvm.ops.read(hw, NVM_ID_LED_SETTINGS, 1, data);
1362 	if (ret_val) {
1363 		hw_dbg("NVM Read Error\n");
1364 		goto out;
1365 	}
1366 
1367 	if (*data == ID_LED_RESERVED_0000 || *data == ID_LED_RESERVED_FFFF) {
1368 		switch (hw->phy.media_type) {
1369 		case e1000_media_type_internal_serdes:
1370 			*data = ID_LED_DEFAULT_82575_SERDES;
1371 			break;
1372 		case e1000_media_type_copper:
1373 		default:
1374 			*data = ID_LED_DEFAULT;
1375 			break;
1376 		}
1377 	}
1378 out:
1379 	return ret_val;
1380 }
1381 
1382 /**
1383  *  igb_id_led_init -
1384  *  @hw: pointer to the HW structure
1385  *
1386  **/
1387 s32 igb_id_led_init(struct e1000_hw *hw)
1388 {
1389 	struct e1000_mac_info *mac = &hw->mac;
1390 	s32 ret_val;
1391 	const u32 ledctl_mask = 0x000000FF;
1392 	const u32 ledctl_on = E1000_LEDCTL_MODE_LED_ON;
1393 	const u32 ledctl_off = E1000_LEDCTL_MODE_LED_OFF;
1394 	u16 data, i, temp;
1395 	const u16 led_mask = 0x0F;
1396 
1397 	/* i210 and i211 devices have different LED mechanism */
1398 	if ((hw->mac.type == e1000_i210) ||
1399 	    (hw->mac.type == e1000_i211))
1400 		ret_val = igb_valid_led_default_i210(hw, &data);
1401 	else
1402 		ret_val = igb_valid_led_default(hw, &data);
1403 
1404 	if (ret_val)
1405 		goto out;
1406 
1407 	mac->ledctl_default = rd32(E1000_LEDCTL);
1408 	mac->ledctl_mode1 = mac->ledctl_default;
1409 	mac->ledctl_mode2 = mac->ledctl_default;
1410 
1411 	for (i = 0; i < 4; i++) {
1412 		temp = (data >> (i << 2)) & led_mask;
1413 		switch (temp) {
1414 		case ID_LED_ON1_DEF2:
1415 		case ID_LED_ON1_ON2:
1416 		case ID_LED_ON1_OFF2:
1417 			mac->ledctl_mode1 &= ~(ledctl_mask << (i << 3));
1418 			mac->ledctl_mode1 |= ledctl_on << (i << 3);
1419 			break;
1420 		case ID_LED_OFF1_DEF2:
1421 		case ID_LED_OFF1_ON2:
1422 		case ID_LED_OFF1_OFF2:
1423 			mac->ledctl_mode1 &= ~(ledctl_mask << (i << 3));
1424 			mac->ledctl_mode1 |= ledctl_off << (i << 3);
1425 			break;
1426 		default:
1427 			/* Do nothing */
1428 			break;
1429 		}
1430 		switch (temp) {
1431 		case ID_LED_DEF1_ON2:
1432 		case ID_LED_ON1_ON2:
1433 		case ID_LED_OFF1_ON2:
1434 			mac->ledctl_mode2 &= ~(ledctl_mask << (i << 3));
1435 			mac->ledctl_mode2 |= ledctl_on << (i << 3);
1436 			break;
1437 		case ID_LED_DEF1_OFF2:
1438 		case ID_LED_ON1_OFF2:
1439 		case ID_LED_OFF1_OFF2:
1440 			mac->ledctl_mode2 &= ~(ledctl_mask << (i << 3));
1441 			mac->ledctl_mode2 |= ledctl_off << (i << 3);
1442 			break;
1443 		default:
1444 			/* Do nothing */
1445 			break;
1446 		}
1447 	}
1448 
1449 out:
1450 	return ret_val;
1451 }
1452 
1453 /**
1454  *  igb_cleanup_led - Set LED config to default operation
1455  *  @hw: pointer to the HW structure
1456  *
1457  *  Remove the current LED configuration and set the LED configuration
1458  *  to the default value, saved from the EEPROM.
1459  **/
1460 s32 igb_cleanup_led(struct e1000_hw *hw)
1461 {
1462 	wr32(E1000_LEDCTL, hw->mac.ledctl_default);
1463 	return 0;
1464 }
1465 
1466 /**
1467  *  igb_blink_led - Blink LED
1468  *  @hw: pointer to the HW structure
1469  *
1470  *  Blink the led's which are set to be on.
1471  **/
1472 s32 igb_blink_led(struct e1000_hw *hw)
1473 {
1474 	u32 ledctl_blink = 0;
1475 	u32 i;
1476 
1477 	if (hw->phy.media_type == e1000_media_type_fiber) {
1478 		/* always blink LED0 for PCI-E fiber */
1479 		ledctl_blink = E1000_LEDCTL_LED0_BLINK |
1480 		     (E1000_LEDCTL_MODE_LED_ON << E1000_LEDCTL_LED0_MODE_SHIFT);
1481 	} else {
1482 		/* Set the blink bit for each LED that's "on" (0x0E)
1483 		 * (or "off" if inverted) in ledctl_mode2.  The blink
1484 		 * logic in hardware only works when mode is set to "on"
1485 		 * so it must be changed accordingly when the mode is
1486 		 * "off" and inverted.
1487 		 */
1488 		ledctl_blink = hw->mac.ledctl_mode2;
1489 		for (i = 0; i < 32; i += 8) {
1490 			u32 mode = (hw->mac.ledctl_mode2 >> i) &
1491 			    E1000_LEDCTL_LED0_MODE_MASK;
1492 			u32 led_default = hw->mac.ledctl_default >> i;
1493 
1494 			if ((!(led_default & E1000_LEDCTL_LED0_IVRT) &&
1495 			     (mode == E1000_LEDCTL_MODE_LED_ON)) ||
1496 			    ((led_default & E1000_LEDCTL_LED0_IVRT) &&
1497 			     (mode == E1000_LEDCTL_MODE_LED_OFF))) {
1498 				ledctl_blink &=
1499 				    ~(E1000_LEDCTL_LED0_MODE_MASK << i);
1500 				ledctl_blink |= (E1000_LEDCTL_LED0_BLINK |
1501 						 E1000_LEDCTL_MODE_LED_ON) << i;
1502 			}
1503 		}
1504 	}
1505 
1506 	wr32(E1000_LEDCTL, ledctl_blink);
1507 
1508 	return 0;
1509 }
1510 
1511 /**
1512  *  igb_led_off - Turn LED off
1513  *  @hw: pointer to the HW structure
1514  *
1515  *  Turn LED off.
1516  **/
1517 s32 igb_led_off(struct e1000_hw *hw)
1518 {
1519 	switch (hw->phy.media_type) {
1520 	case e1000_media_type_copper:
1521 		wr32(E1000_LEDCTL, hw->mac.ledctl_mode1);
1522 		break;
1523 	default:
1524 		break;
1525 	}
1526 
1527 	return 0;
1528 }
1529 
1530 /**
1531  *  igb_disable_pcie_master - Disables PCI-express master access
1532  *  @hw: pointer to the HW structure
1533  *
1534  *  Returns 0 (0) if successful, else returns -10
1535  *  (-E1000_ERR_MASTER_REQUESTS_PENDING) if master disable bit has not caused
1536  *  the master requests to be disabled.
1537  *
1538  *  Disables PCI-Express master access and verifies there are no pending
1539  *  requests.
1540  **/
1541 s32 igb_disable_pcie_master(struct e1000_hw *hw)
1542 {
1543 	u32 ctrl;
1544 	s32 timeout = MASTER_DISABLE_TIMEOUT;
1545 	s32 ret_val = 0;
1546 
1547 	if (hw->bus.type != e1000_bus_type_pci_express)
1548 		goto out;
1549 
1550 	ctrl = rd32(E1000_CTRL);
1551 	ctrl |= E1000_CTRL_GIO_MASTER_DISABLE;
1552 	wr32(E1000_CTRL, ctrl);
1553 
1554 	while (timeout) {
1555 		if (!(rd32(E1000_STATUS) &
1556 		      E1000_STATUS_GIO_MASTER_ENABLE))
1557 			break;
1558 		udelay(100);
1559 		timeout--;
1560 	}
1561 
1562 	if (!timeout) {
1563 		hw_dbg("Master requests are pending.\n");
1564 		ret_val = -E1000_ERR_MASTER_REQUESTS_PENDING;
1565 		goto out;
1566 	}
1567 
1568 out:
1569 	return ret_val;
1570 }
1571 
1572 /**
1573  *  igb_validate_mdi_setting - Verify MDI/MDIx settings
1574  *  @hw: pointer to the HW structure
1575  *
1576  *  Verify that when not using auto-negotitation that MDI/MDIx is correctly
1577  *  set, which is forced to MDI mode only.
1578  **/
1579 s32 igb_validate_mdi_setting(struct e1000_hw *hw)
1580 {
1581 	s32 ret_val = 0;
1582 
1583 	/* All MDI settings are supported on 82580 and newer. */
1584 	if (hw->mac.type >= e1000_82580)
1585 		goto out;
1586 
1587 	if (!hw->mac.autoneg && (hw->phy.mdix == 0 || hw->phy.mdix == 3)) {
1588 		hw_dbg("Invalid MDI setting detected\n");
1589 		hw->phy.mdix = 1;
1590 		ret_val = -E1000_ERR_CONFIG;
1591 		goto out;
1592 	}
1593 
1594 out:
1595 	return ret_val;
1596 }
1597 
1598 /**
1599  *  igb_write_8bit_ctrl_reg - Write a 8bit CTRL register
1600  *  @hw: pointer to the HW structure
1601  *  @reg: 32bit register offset such as E1000_SCTL
1602  *  @offset: register offset to write to
1603  *  @data: data to write at register offset
1604  *
1605  *  Writes an address/data control type register.  There are several of these
1606  *  and they all have the format address << 8 | data and bit 31 is polled for
1607  *  completion.
1608  **/
1609 s32 igb_write_8bit_ctrl_reg(struct e1000_hw *hw, u32 reg,
1610 			      u32 offset, u8 data)
1611 {
1612 	u32 i, regvalue = 0;
1613 	s32 ret_val = 0;
1614 
1615 	/* Set up the address and data */
1616 	regvalue = ((u32)data) | (offset << E1000_GEN_CTL_ADDRESS_SHIFT);
1617 	wr32(reg, regvalue);
1618 
1619 	/* Poll the ready bit to see if the MDI read completed */
1620 	for (i = 0; i < E1000_GEN_POLL_TIMEOUT; i++) {
1621 		udelay(5);
1622 		regvalue = rd32(reg);
1623 		if (regvalue & E1000_GEN_CTL_READY)
1624 			break;
1625 	}
1626 	if (!(regvalue & E1000_GEN_CTL_READY)) {
1627 		hw_dbg("Reg %08x did not indicate ready\n", reg);
1628 		ret_val = -E1000_ERR_PHY;
1629 		goto out;
1630 	}
1631 
1632 out:
1633 	return ret_val;
1634 }
1635 
1636 /**
1637  *  igb_enable_mng_pass_thru - Enable processing of ARP's
1638  *  @hw: pointer to the HW structure
1639  *
1640  *  Verifies the hardware needs to leave interface enabled so that frames can
1641  *  be directed to and from the management interface.
1642  **/
1643 bool igb_enable_mng_pass_thru(struct e1000_hw *hw)
1644 {
1645 	u32 manc;
1646 	u32 fwsm, factps;
1647 	bool ret_val = false;
1648 
1649 	if (!hw->mac.asf_firmware_present)
1650 		goto out;
1651 
1652 	manc = rd32(E1000_MANC);
1653 
1654 	if (!(manc & E1000_MANC_RCV_TCO_EN))
1655 		goto out;
1656 
1657 	if (hw->mac.arc_subsystem_valid) {
1658 		fwsm = rd32(E1000_FWSM);
1659 		factps = rd32(E1000_FACTPS);
1660 
1661 		if (!(factps & E1000_FACTPS_MNGCG) &&
1662 		    ((fwsm & E1000_FWSM_MODE_MASK) ==
1663 		     (e1000_mng_mode_pt << E1000_FWSM_MODE_SHIFT))) {
1664 			ret_val = true;
1665 			goto out;
1666 		}
1667 	} else {
1668 		if ((manc & E1000_MANC_SMBUS_EN) &&
1669 		    !(manc & E1000_MANC_ASF_EN)) {
1670 			ret_val = true;
1671 			goto out;
1672 		}
1673 	}
1674 
1675 out:
1676 	return ret_val;
1677 }
1678