1 /******************************************************************************
2  *
3  * This file is provided under a dual BSD/GPLv2 license.  When using or
4  * redistributing this file, you may do so under either license.
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6  * GPL LICENSE SUMMARY
7  *
8  * Copyright(c) 2017 Intel Deutschland GmbH
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of version 2 of the GNU General Public License as
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17  * General Public License for more details.
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50  *****************************************************************************/
51 #include "iwl-trans.h"
52 #include "iwl-context-info.h"
53 #include "internal.h"
54 
55 /*
56  * Start up NIC's basic functionality after it has been reset
57  * (e.g. after platform boot, or shutdown via iwl_pcie_apm_stop())
58  * NOTE:  This does not load uCode nor start the embedded processor
59  */
60 static int iwl_pcie_gen2_apm_init(struct iwl_trans *trans)
61 {
62 	int ret = 0;
63 
64 	IWL_DEBUG_INFO(trans, "Init card's basic functions\n");
65 
66 	/*
67 	 * Use "set_bit" below rather than "write", to preserve any hardware
68 	 * bits already set by default after reset.
69 	 */
70 
71 	/*
72 	 * Disable L0s without affecting L1;
73 	 * don't wait for ICH L0s (ICH bug W/A)
74 	 */
75 	iwl_set_bit(trans, CSR_GIO_CHICKEN_BITS,
76 		    CSR_GIO_CHICKEN_BITS_REG_BIT_L1A_NO_L0S_RX);
77 
78 	/* Set FH wait threshold to maximum (HW error during stress W/A) */
79 	iwl_set_bit(trans, CSR_DBG_HPET_MEM_REG, CSR_DBG_HPET_MEM_REG_VAL);
80 
81 	/*
82 	 * Enable HAP INTA (interrupt from management bus) to
83 	 * wake device's PCI Express link L1a -> L0s
84 	 */
85 	iwl_set_bit(trans, CSR_HW_IF_CONFIG_REG,
86 		    CSR_HW_IF_CONFIG_REG_BIT_HAP_WAKE_L1A);
87 
88 	iwl_pcie_apm_config(trans);
89 
90 	/*
91 	 * Set "initialization complete" bit to move adapter from
92 	 * D0U* --> D0A* (powered-up active) state.
93 	 */
94 	iwl_set_bit(trans, CSR_GP_CNTRL, CSR_GP_CNTRL_REG_FLAG_INIT_DONE);
95 
96 	/*
97 	 * Wait for clock stabilization; once stabilized, access to
98 	 * device-internal resources is supported, e.g. iwl_write_prph()
99 	 * and accesses to uCode SRAM.
100 	 */
101 	ret = iwl_poll_bit(trans, CSR_GP_CNTRL,
102 			   CSR_GP_CNTRL_REG_FLAG_MAC_CLOCK_READY,
103 			   CSR_GP_CNTRL_REG_FLAG_MAC_CLOCK_READY, 25000);
104 	if (ret < 0) {
105 		IWL_DEBUG_INFO(trans, "Failed to init the card\n");
106 		return ret;
107 	}
108 
109 	set_bit(STATUS_DEVICE_ENABLED, &trans->status);
110 
111 	return 0;
112 }
113 
114 static void iwl_pcie_gen2_apm_stop(struct iwl_trans *trans, bool op_mode_leave)
115 {
116 	IWL_DEBUG_INFO(trans, "Stop card, put in low power state\n");
117 
118 	if (op_mode_leave) {
119 		if (!test_bit(STATUS_DEVICE_ENABLED, &trans->status))
120 			iwl_pcie_gen2_apm_init(trans);
121 
122 		/* inform ME that we are leaving */
123 		iwl_set_bit(trans, CSR_DBG_LINK_PWR_MGMT_REG,
124 			    CSR_RESET_LINK_PWR_MGMT_DISABLED);
125 		iwl_set_bit(trans, CSR_HW_IF_CONFIG_REG,
126 			    CSR_HW_IF_CONFIG_REG_PREPARE |
127 			    CSR_HW_IF_CONFIG_REG_ENABLE_PME);
128 		mdelay(1);
129 		iwl_clear_bit(trans, CSR_DBG_LINK_PWR_MGMT_REG,
130 			      CSR_RESET_LINK_PWR_MGMT_DISABLED);
131 		mdelay(5);
132 	}
133 
134 	clear_bit(STATUS_DEVICE_ENABLED, &trans->status);
135 
136 	/* Stop device's DMA activity */
137 	iwl_pcie_apm_stop_master(trans);
138 
139 	/* Reset the entire device */
140 	iwl_set_bit(trans, CSR_RESET, CSR_RESET_REG_FLAG_SW_RESET);
141 	usleep_range(1000, 2000);
142 
143 	/*
144 	 * Clear "initialization complete" bit to move adapter from
145 	 * D0A* (powered-up Active) --> D0U* (Uninitialized) state.
146 	 */
147 	iwl_clear_bit(trans, CSR_GP_CNTRL, CSR_GP_CNTRL_REG_FLAG_INIT_DONE);
148 }
149 
150 void _iwl_trans_pcie_gen2_stop_device(struct iwl_trans *trans, bool low_power)
151 {
152 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
153 	bool hw_rfkill, was_hw_rfkill;
154 
155 	lockdep_assert_held(&trans_pcie->mutex);
156 
157 	if (trans_pcie->is_down)
158 		return;
159 
160 	trans_pcie->is_down = true;
161 
162 	was_hw_rfkill = iwl_is_rfkill_set(trans);
163 
164 	/* tell the device to stop sending interrupts */
165 	iwl_disable_interrupts(trans);
166 
167 	/* device going down, Stop using ICT table */
168 	iwl_pcie_disable_ict(trans);
169 
170 	/*
171 	 * If a HW restart happens during firmware loading,
172 	 * then the firmware loading might call this function
173 	 * and later it might be called again due to the
174 	 * restart. So don't process again if the device is
175 	 * already dead.
176 	 */
177 	if (test_and_clear_bit(STATUS_DEVICE_ENABLED, &trans->status)) {
178 		IWL_DEBUG_INFO(trans,
179 			       "DEVICE_ENABLED bit was set and is now cleared\n");
180 		iwl_pcie_gen2_tx_stop(trans);
181 		iwl_pcie_rx_stop(trans);
182 	}
183 
184 	iwl_pcie_ctxt_info_free_paging(trans);
185 	iwl_pcie_ctxt_info_free(trans);
186 
187 	/* Make sure (redundant) we've released our request to stay awake */
188 	iwl_clear_bit(trans, CSR_GP_CNTRL,
189 		      CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ);
190 
191 	/* Stop the device, and put it in low power state */
192 	iwl_pcie_gen2_apm_stop(trans, false);
193 
194 	/* stop and reset the on-board processor */
195 	iwl_write32(trans, CSR_RESET, CSR_RESET_REG_FLAG_SW_RESET);
196 	usleep_range(1000, 2000);
197 
198 	/*
199 	 * Upon stop, the IVAR table gets erased, so msi-x won't
200 	 * work. This causes a bug in RF-KILL flows, since the interrupt
201 	 * that enables radio won't fire on the correct irq, and the
202 	 * driver won't be able to handle the interrupt.
203 	 * Configure the IVAR table again after reset.
204 	 */
205 	iwl_pcie_conf_msix_hw(trans_pcie);
206 
207 	/*
208 	 * Upon stop, the APM issues an interrupt if HW RF kill is set.
209 	 * This is a bug in certain verions of the hardware.
210 	 * Certain devices also keep sending HW RF kill interrupt all
211 	 * the time, unless the interrupt is ACKed even if the interrupt
212 	 * should be masked. Re-ACK all the interrupts here.
213 	 */
214 	iwl_disable_interrupts(trans);
215 
216 	/* clear all status bits */
217 	clear_bit(STATUS_SYNC_HCMD_ACTIVE, &trans->status);
218 	clear_bit(STATUS_INT_ENABLED, &trans->status);
219 	clear_bit(STATUS_TPOWER_PMI, &trans->status);
220 	clear_bit(STATUS_RFKILL, &trans->status);
221 
222 	/*
223 	 * Even if we stop the HW, we still want the RF kill
224 	 * interrupt
225 	 */
226 	iwl_enable_rfkill_int(trans);
227 
228 	/*
229 	 * Check again since the RF kill state may have changed while
230 	 * all the interrupts were disabled, in this case we couldn't
231 	 * receive the RF kill interrupt and update the state in the
232 	 * op_mode.
233 	 * Don't call the op_mode if the rkfill state hasn't changed.
234 	 * This allows the op_mode to call stop_device from the rfkill
235 	 * notification without endless recursion. Under very rare
236 	 * circumstances, we might have a small recursion if the rfkill
237 	 * state changed exactly now while we were called from stop_device.
238 	 * This is very unlikely but can happen and is supported.
239 	 */
240 	hw_rfkill = iwl_is_rfkill_set(trans);
241 	if (hw_rfkill)
242 		set_bit(STATUS_RFKILL, &trans->status);
243 	else
244 		clear_bit(STATUS_RFKILL, &trans->status);
245 	if (hw_rfkill != was_hw_rfkill)
246 		iwl_trans_pcie_rf_kill(trans, hw_rfkill);
247 
248 	/* re-take ownership to prevent other users from stealing the device */
249 	iwl_pcie_prepare_card_hw(trans);
250 }
251 
252 void iwl_trans_pcie_gen2_stop_device(struct iwl_trans *trans, bool low_power)
253 {
254 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
255 
256 	mutex_lock(&trans_pcie->mutex);
257 	_iwl_trans_pcie_gen2_stop_device(trans, low_power);
258 	mutex_unlock(&trans_pcie->mutex);
259 }
260 
261 static int iwl_pcie_gen2_nic_init(struct iwl_trans *trans)
262 {
263 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
264 
265 	/* TODO: most of the logic can be removed in A0 - but not in Z0 */
266 	spin_lock(&trans_pcie->irq_lock);
267 	iwl_pcie_gen2_apm_init(trans);
268 	spin_unlock(&trans_pcie->irq_lock);
269 
270 	iwl_op_mode_nic_config(trans->op_mode);
271 
272 	/* Allocate the RX queue, or reset if it is already allocated */
273 	if (iwl_pcie_gen2_rx_init(trans))
274 		return -ENOMEM;
275 
276 	/* Allocate or reset and init all Tx and Command queues */
277 	if (iwl_pcie_gen2_tx_init(trans))
278 		return -ENOMEM;
279 
280 	/* enable shadow regs in HW */
281 	iwl_set_bit(trans, CSR_MAC_SHADOW_REG_CTRL, 0x800FFFFF);
282 	IWL_DEBUG_INFO(trans, "Enabling shadow registers in device\n");
283 
284 	return 0;
285 }
286 
287 void iwl_trans_pcie_gen2_fw_alive(struct iwl_trans *trans, u32 scd_addr)
288 {
289 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
290 
291 	iwl_pcie_reset_ict(trans);
292 
293 	/* make sure all queue are not stopped/used */
294 	memset(trans_pcie->queue_stopped, 0, sizeof(trans_pcie->queue_stopped));
295 	memset(trans_pcie->queue_used, 0, sizeof(trans_pcie->queue_used));
296 
297 	/* now that we got alive we can free the fw image & the context info.
298 	 * paging memory cannot be freed included since FW will still use it
299 	 */
300 	iwl_pcie_ctxt_info_free(trans);
301 }
302 
303 int iwl_trans_pcie_gen2_start_fw(struct iwl_trans *trans,
304 				 const struct fw_img *fw, bool run_in_rfkill)
305 {
306 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
307 	bool hw_rfkill;
308 	int ret;
309 
310 	/* This may fail if AMT took ownership of the device */
311 	if (iwl_pcie_prepare_card_hw(trans)) {
312 		IWL_WARN(trans, "Exit HW not ready\n");
313 		ret = -EIO;
314 		goto out;
315 	}
316 
317 	iwl_enable_rfkill_int(trans);
318 
319 	iwl_write32(trans, CSR_INT, 0xFFFFFFFF);
320 
321 	/*
322 	 * We enabled the RF-Kill interrupt and the handler may very
323 	 * well be running. Disable the interrupts to make sure no other
324 	 * interrupt can be fired.
325 	 */
326 	iwl_disable_interrupts(trans);
327 
328 	/* Make sure it finished running */
329 	iwl_pcie_synchronize_irqs(trans);
330 
331 	mutex_lock(&trans_pcie->mutex);
332 
333 	/* If platform's RF_KILL switch is NOT set to KILL */
334 	hw_rfkill = iwl_trans_check_hw_rf_kill(trans);
335 	if (hw_rfkill && !run_in_rfkill) {
336 		ret = -ERFKILL;
337 		goto out;
338 	}
339 
340 	/* Someone called stop_device, don't try to start_fw */
341 	if (trans_pcie->is_down) {
342 		IWL_WARN(trans,
343 			 "Can't start_fw since the HW hasn't been started\n");
344 		ret = -EIO;
345 		goto out;
346 	}
347 
348 	/* make sure rfkill handshake bits are cleared */
349 	iwl_write32(trans, CSR_UCODE_DRV_GP1_CLR, CSR_UCODE_SW_BIT_RFKILL);
350 	iwl_write32(trans, CSR_UCODE_DRV_GP1_CLR,
351 		    CSR_UCODE_DRV_GP1_BIT_CMD_BLOCKED);
352 
353 	/* clear (again), then enable host interrupts */
354 	iwl_write32(trans, CSR_INT, 0xFFFFFFFF);
355 
356 	ret = iwl_pcie_gen2_nic_init(trans);
357 	if (ret) {
358 		IWL_ERR(trans, "Unable to init nic\n");
359 		goto out;
360 	}
361 
362 	ret = iwl_pcie_ctxt_info_init(trans, fw);
363 	if (ret)
364 		goto out;
365 
366 	/* re-check RF-Kill state since we may have missed the interrupt */
367 	hw_rfkill = iwl_trans_check_hw_rf_kill(trans);
368 	if (hw_rfkill && !run_in_rfkill)
369 		ret = -ERFKILL;
370 
371 out:
372 	mutex_unlock(&trans_pcie->mutex);
373 	return ret;
374 }
375