xref: /linux/drivers/net/wireless/intel/iwlwifi/pcie/trans-gen2.c (revision a460513ed4b6994bfeb7bd86f72853140bc1ac12)
1 // SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
2 /*
3  * Copyright (C) 2017 Intel Deutschland GmbH
4  * Copyright (C) 2018-2020 Intel Corporation
5  */
6 #include "iwl-trans.h"
7 #include "iwl-prph.h"
8 #include "iwl-context-info.h"
9 #include "iwl-context-info-gen3.h"
10 #include "internal.h"
11 #include "fw/dbg.h"
12 
13 #define FW_RESET_TIMEOUT (HZ / 5)
14 
15 /*
16  * Start up NIC's basic functionality after it has been reset
17  * (e.g. after platform boot, or shutdown via iwl_pcie_apm_stop())
18  * NOTE:  This does not load uCode nor start the embedded processor
19  */
20 int iwl_pcie_gen2_apm_init(struct iwl_trans *trans)
21 {
22 	int ret = 0;
23 
24 	IWL_DEBUG_INFO(trans, "Init card's basic functions\n");
25 
26 	/*
27 	 * Use "set_bit" below rather than "write", to preserve any hardware
28 	 * bits already set by default after reset.
29 	 */
30 
31 	/*
32 	 * Disable L0s without affecting L1;
33 	 * don't wait for ICH L0s (ICH bug W/A)
34 	 */
35 	iwl_set_bit(trans, CSR_GIO_CHICKEN_BITS,
36 		    CSR_GIO_CHICKEN_BITS_REG_BIT_L1A_NO_L0S_RX);
37 
38 	/* Set FH wait threshold to maximum (HW error during stress W/A) */
39 	iwl_set_bit(trans, CSR_DBG_HPET_MEM_REG, CSR_DBG_HPET_MEM_REG_VAL);
40 
41 	/*
42 	 * Enable HAP INTA (interrupt from management bus) to
43 	 * wake device's PCI Express link L1a -> L0s
44 	 */
45 	iwl_set_bit(trans, CSR_HW_IF_CONFIG_REG,
46 		    CSR_HW_IF_CONFIG_REG_BIT_HAP_WAKE_L1A);
47 
48 	iwl_pcie_apm_config(trans);
49 
50 	ret = iwl_finish_nic_init(trans, trans->trans_cfg);
51 	if (ret)
52 		return ret;
53 
54 	set_bit(STATUS_DEVICE_ENABLED, &trans->status);
55 
56 	return 0;
57 }
58 
59 static void iwl_pcie_gen2_apm_stop(struct iwl_trans *trans, bool op_mode_leave)
60 {
61 	IWL_DEBUG_INFO(trans, "Stop card, put in low power state\n");
62 
63 	if (op_mode_leave) {
64 		if (!test_bit(STATUS_DEVICE_ENABLED, &trans->status))
65 			iwl_pcie_gen2_apm_init(trans);
66 
67 		/* inform ME that we are leaving */
68 		iwl_set_bit(trans, CSR_DBG_LINK_PWR_MGMT_REG,
69 			    CSR_RESET_LINK_PWR_MGMT_DISABLED);
70 		iwl_set_bit(trans, CSR_HW_IF_CONFIG_REG,
71 			    CSR_HW_IF_CONFIG_REG_PREPARE |
72 			    CSR_HW_IF_CONFIG_REG_ENABLE_PME);
73 		mdelay(1);
74 		iwl_clear_bit(trans, CSR_DBG_LINK_PWR_MGMT_REG,
75 			      CSR_RESET_LINK_PWR_MGMT_DISABLED);
76 		mdelay(5);
77 	}
78 
79 	clear_bit(STATUS_DEVICE_ENABLED, &trans->status);
80 
81 	/* Stop device's DMA activity */
82 	iwl_pcie_apm_stop_master(trans);
83 
84 	iwl_trans_sw_reset(trans);
85 
86 	/*
87 	 * Clear "initialization complete" bit to move adapter from
88 	 * D0A* (powered-up Active) --> D0U* (Uninitialized) state.
89 	 */
90 	iwl_clear_bit(trans, CSR_GP_CNTRL, CSR_GP_CNTRL_REG_FLAG_INIT_DONE);
91 }
92 
93 static void iwl_trans_pcie_fw_reset_handshake(struct iwl_trans *trans)
94 {
95 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
96 	int ret;
97 
98 	trans_pcie->fw_reset_done = false;
99 
100 	if (trans->trans_cfg->device_family < IWL_DEVICE_FAMILY_AX210)
101 		iwl_write_umac_prph(trans, UREG_NIC_SET_NMI_DRIVER,
102 				    UREG_NIC_SET_NMI_DRIVER_RESET_HANDSHAKE);
103 	else
104 		iwl_write_umac_prph(trans, UREG_DOORBELL_TO_ISR6,
105 				    UREG_DOORBELL_TO_ISR6_RESET_HANDSHAKE);
106 
107 	/* wait 200ms */
108 	ret = wait_event_timeout(trans_pcie->fw_reset_waitq,
109 				 trans_pcie->fw_reset_done, FW_RESET_TIMEOUT);
110 	if (!ret)
111 		IWL_ERR(trans,
112 			"firmware didn't ACK the reset - continue anyway\n");
113 }
114 
115 void _iwl_trans_pcie_gen2_stop_device(struct iwl_trans *trans)
116 {
117 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
118 
119 	lockdep_assert_held(&trans_pcie->mutex);
120 
121 	if (trans_pcie->is_down)
122 		return;
123 
124 	if (trans_pcie->fw_reset_handshake &&
125 	    trans->state >= IWL_TRANS_FW_STARTED)
126 		iwl_trans_pcie_fw_reset_handshake(trans);
127 
128 	trans_pcie->is_down = true;
129 
130 	/* tell the device to stop sending interrupts */
131 	iwl_disable_interrupts(trans);
132 
133 	/* device going down, Stop using ICT table */
134 	iwl_pcie_disable_ict(trans);
135 
136 	/*
137 	 * If a HW restart happens during firmware loading,
138 	 * then the firmware loading might call this function
139 	 * and later it might be called again due to the
140 	 * restart. So don't process again if the device is
141 	 * already dead.
142 	 */
143 	if (test_and_clear_bit(STATUS_DEVICE_ENABLED, &trans->status)) {
144 		IWL_DEBUG_INFO(trans,
145 			       "DEVICE_ENABLED bit was set and is now cleared\n");
146 		iwl_txq_gen2_tx_stop(trans);
147 		iwl_pcie_rx_stop(trans);
148 	}
149 
150 	iwl_pcie_ctxt_info_free_paging(trans);
151 	if (trans->trans_cfg->device_family >= IWL_DEVICE_FAMILY_AX210)
152 		iwl_pcie_ctxt_info_gen3_free(trans);
153 	else
154 		iwl_pcie_ctxt_info_free(trans);
155 
156 	/* Make sure (redundant) we've released our request to stay awake */
157 	iwl_clear_bit(trans, CSR_GP_CNTRL,
158 		      CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ);
159 
160 	/* Stop the device, and put it in low power state */
161 	iwl_pcie_gen2_apm_stop(trans, false);
162 
163 	iwl_trans_sw_reset(trans);
164 
165 	/*
166 	 * Upon stop, the IVAR table gets erased, so msi-x won't
167 	 * work. This causes a bug in RF-KILL flows, since the interrupt
168 	 * that enables radio won't fire on the correct irq, and the
169 	 * driver won't be able to handle the interrupt.
170 	 * Configure the IVAR table again after reset.
171 	 */
172 	iwl_pcie_conf_msix_hw(trans_pcie);
173 
174 	/*
175 	 * Upon stop, the APM issues an interrupt if HW RF kill is set.
176 	 * This is a bug in certain verions of the hardware.
177 	 * Certain devices also keep sending HW RF kill interrupt all
178 	 * the time, unless the interrupt is ACKed even if the interrupt
179 	 * should be masked. Re-ACK all the interrupts here.
180 	 */
181 	iwl_disable_interrupts(trans);
182 
183 	/* clear all status bits */
184 	clear_bit(STATUS_SYNC_HCMD_ACTIVE, &trans->status);
185 	clear_bit(STATUS_INT_ENABLED, &trans->status);
186 	clear_bit(STATUS_TPOWER_PMI, &trans->status);
187 
188 	/*
189 	 * Even if we stop the HW, we still want the RF kill
190 	 * interrupt
191 	 */
192 	iwl_enable_rfkill_int(trans);
193 
194 	/* re-take ownership to prevent other users from stealing the device */
195 	iwl_pcie_prepare_card_hw(trans);
196 }
197 
198 void iwl_trans_pcie_gen2_stop_device(struct iwl_trans *trans)
199 {
200 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
201 	bool was_in_rfkill;
202 
203 	iwl_op_mode_time_point(trans->op_mode,
204 			       IWL_FW_INI_TIME_POINT_HOST_DEVICE_DISABLE,
205 			       NULL);
206 
207 	mutex_lock(&trans_pcie->mutex);
208 	trans_pcie->opmode_down = true;
209 	was_in_rfkill = test_bit(STATUS_RFKILL_OPMODE, &trans->status);
210 	_iwl_trans_pcie_gen2_stop_device(trans);
211 	iwl_trans_pcie_handle_stop_rfkill(trans, was_in_rfkill);
212 	mutex_unlock(&trans_pcie->mutex);
213 }
214 
215 static int iwl_pcie_gen2_nic_init(struct iwl_trans *trans)
216 {
217 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
218 	int queue_size = max_t(u32, IWL_CMD_QUEUE_SIZE,
219 			       trans->cfg->min_txq_size);
220 
221 	/* TODO: most of the logic can be removed in A0 - but not in Z0 */
222 	spin_lock_bh(&trans_pcie->irq_lock);
223 	iwl_pcie_gen2_apm_init(trans);
224 	spin_unlock_bh(&trans_pcie->irq_lock);
225 
226 	iwl_op_mode_nic_config(trans->op_mode);
227 
228 	/* Allocate the RX queue, or reset if it is already allocated */
229 	if (iwl_pcie_gen2_rx_init(trans))
230 		return -ENOMEM;
231 
232 	/* Allocate or reset and init all Tx and Command queues */
233 	if (iwl_txq_gen2_init(trans, trans->txqs.cmd.q_id, queue_size))
234 		return -ENOMEM;
235 
236 	/* enable shadow regs in HW */
237 	iwl_set_bit(trans, CSR_MAC_SHADOW_REG_CTRL, 0x800FFFFF);
238 	IWL_DEBUG_INFO(trans, "Enabling shadow registers in device\n");
239 
240 	return 0;
241 }
242 
243 void iwl_trans_pcie_gen2_fw_alive(struct iwl_trans *trans, u32 scd_addr)
244 {
245 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
246 
247 	iwl_pcie_reset_ict(trans);
248 
249 	/* make sure all queue are not stopped/used */
250 	memset(trans->txqs.queue_stopped, 0,
251 	       sizeof(trans->txqs.queue_stopped));
252 	memset(trans->txqs.queue_used, 0, sizeof(trans->txqs.queue_used));
253 
254 	/* now that we got alive we can free the fw image & the context info.
255 	 * paging memory cannot be freed included since FW will still use it
256 	 */
257 	iwl_pcie_ctxt_info_free(trans);
258 
259 	/*
260 	 * Re-enable all the interrupts, including the RF-Kill one, now that
261 	 * the firmware is alive.
262 	 */
263 	iwl_enable_interrupts(trans);
264 	mutex_lock(&trans_pcie->mutex);
265 	iwl_pcie_check_hw_rf_kill(trans);
266 	mutex_unlock(&trans_pcie->mutex);
267 }
268 
269 int iwl_trans_pcie_gen2_start_fw(struct iwl_trans *trans,
270 				 const struct fw_img *fw, bool run_in_rfkill)
271 {
272 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
273 	bool hw_rfkill;
274 	int ret;
275 
276 	/* This may fail if AMT took ownership of the device */
277 	if (iwl_pcie_prepare_card_hw(trans)) {
278 		IWL_WARN(trans, "Exit HW not ready\n");
279 		ret = -EIO;
280 		goto out;
281 	}
282 
283 	iwl_enable_rfkill_int(trans);
284 
285 	iwl_write32(trans, CSR_INT, 0xFFFFFFFF);
286 
287 	/*
288 	 * We enabled the RF-Kill interrupt and the handler may very
289 	 * well be running. Disable the interrupts to make sure no other
290 	 * interrupt can be fired.
291 	 */
292 	iwl_disable_interrupts(trans);
293 
294 	/* Make sure it finished running */
295 	iwl_pcie_synchronize_irqs(trans);
296 
297 	mutex_lock(&trans_pcie->mutex);
298 
299 	/* If platform's RF_KILL switch is NOT set to KILL */
300 	hw_rfkill = iwl_pcie_check_hw_rf_kill(trans);
301 	if (hw_rfkill && !run_in_rfkill) {
302 		ret = -ERFKILL;
303 		goto out;
304 	}
305 
306 	/* Someone called stop_device, don't try to start_fw */
307 	if (trans_pcie->is_down) {
308 		IWL_WARN(trans,
309 			 "Can't start_fw since the HW hasn't been started\n");
310 		ret = -EIO;
311 		goto out;
312 	}
313 
314 	/* make sure rfkill handshake bits are cleared */
315 	iwl_write32(trans, CSR_UCODE_DRV_GP1_CLR, CSR_UCODE_SW_BIT_RFKILL);
316 	iwl_write32(trans, CSR_UCODE_DRV_GP1_CLR,
317 		    CSR_UCODE_DRV_GP1_BIT_CMD_BLOCKED);
318 
319 	/* clear (again), then enable host interrupts */
320 	iwl_write32(trans, CSR_INT, 0xFFFFFFFF);
321 
322 	ret = iwl_pcie_gen2_nic_init(trans);
323 	if (ret) {
324 		IWL_ERR(trans, "Unable to init nic\n");
325 		goto out;
326 	}
327 
328 	if (trans->trans_cfg->device_family >= IWL_DEVICE_FAMILY_AX210)
329 		ret = iwl_pcie_ctxt_info_gen3_init(trans, fw);
330 	else
331 		ret = iwl_pcie_ctxt_info_init(trans, fw);
332 	if (ret)
333 		goto out;
334 
335 	/* re-check RF-Kill state since we may have missed the interrupt */
336 	hw_rfkill = iwl_pcie_check_hw_rf_kill(trans);
337 	if (hw_rfkill && !run_in_rfkill)
338 		ret = -ERFKILL;
339 
340 out:
341 	mutex_unlock(&trans_pcie->mutex);
342 	return ret;
343 }
344