1 // SPDX-License-Identifier: GPL-2.0
3 /* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved.
4  * Copyright (C) 2019-2020 Linaro Ltd.
15 #include "ipa.h"
20  * DOC: IPA SMP2P communication with the modem
23  * the modem.  The IPA driver uses this for two purposes:  to enable the modem
25  * state of the IPA clock in the event of a crash.
29  * latter case, the modem uses an SMP2P interrupt to tell the AP IPA driver
32  * The modem is also able to inquire about the current state of the IPA
33  * clock by trigging another SMP2P interrupt to the AP.  We communicate
34  * whether the clock is enabled using two SMP2P state bits--one to
35  * indicate the clock state (on or off), and a second to indicate the
36  * clock state bit is valid.  The modem will poll the valid bit until it
37  * is set, and at that time records whether the AP has the IPA clock enabled.
44  * struct ipa_smp2p - IPA SMP2P information
45  * @ipa:		IPA pointer
46  * @valid_state:	SMEM state indicating enabled state is valid
47  * @enabled_state:	SMEM state to indicate clock is enabled
48  * @valid_bit:		Valid bit in 32-bit SMEM state mask
49  * @enabled_bit:	Enabled bit in 32-bit SMEM state mask
50  * @enabled_bit:	Enabled bit in 32-bit SMEM state mask
51  * @clock_query_irq:	IPA interrupt triggered by modem for clock query
52  * @setup_ready_irq:	IPA interrupt triggered by modem to signal GSI ready
53  * @clock_on:		Whether IPA clock is on
54  * @notified:		Whether modem has been notified of clock state
56  * @mutex:		Mutex protecting ready-interrupt/shutdown interlock
60 	struct ipa *ipa;  member
75  * ipa_smp2p_notify() - use SMP2P to tell modem about IPA clock state
79  * the modem clock query IPA interrupt) or whenever the AP is shutting down
80  * (via a panic notifier).  It sets the two SMP2P state bits--one saying
81  * whether the IPA clock is running, and the other indicating the first bit
82  * is valid.
89 	if (smp2p->notified)  in ipa_smp2p_notify()
92 	smp2p->clock_on = ipa_clock_get_additional(smp2p->ipa);  in ipa_smp2p_notify()
94 	/* Signal whether the clock is enabled */  in ipa_smp2p_notify()
95 	mask = BIT(smp2p->enabled_bit);  in ipa_smp2p_notify()
96 	value = smp2p->clock_on ? mask : 0;  in ipa_smp2p_notify()
97 	qcom_smem_state_update_bits(smp2p->enabled_state, mask, value);  in ipa_smp2p_notify()
99 	/* Now indicate that the enabled flag is valid */  in ipa_smp2p_notify()
100 	mask = BIT(smp2p->valid_bit);  in ipa_smp2p_notify()
102 	qcom_smem_state_update_bits(smp2p->valid_state, mask, value);  in ipa_smp2p_notify()
104 	smp2p->notified = true;  in ipa_smp2p_notify()
107 /* Threaded IRQ handler for modem "ipa-clock-query" SMP2P interrupt */
126 	if (smp2p->clock_on)  in ipa_smp2p_panic_notifier()
127 		ipa_uc_panic_notifier(smp2p->ipa);  in ipa_smp2p_panic_notifier()
134 	/* IPA panic handler needs to run before modem shuts down */  in ipa_smp2p_panic_notifier_register()
135 	smp2p->panic_notifier.notifier_call = ipa_smp2p_panic_notifier;  in ipa_smp2p_panic_notifier_register()
136 	smp2p->panic_notifier.priority = INT_MAX;	/* Do it early */  in ipa_smp2p_panic_notifier_register()
139 					      &smp2p->panic_notifier);  in ipa_smp2p_panic_notifier_register()
145 					 &smp2p->panic_notifier);  in ipa_smp2p_panic_notifier_unregister()
148 /* Threaded IRQ handler for modem "ipa-setup-ready" SMP2P interrupt */
153 	mutex_lock(&smp2p->mutex);  in ipa_smp2p_modem_setup_ready_isr()
155 	if (!smp2p->disabled) {  in ipa_smp2p_modem_setup_ready_isr()
158 		ret = ipa_setup(smp2p->ipa);  in ipa_smp2p_modem_setup_ready_isr()
160 			dev_err(&smp2p->ipa->pdev->dev,  in ipa_smp2p_modem_setup_ready_isr()
162 		smp2p->disabled = true;  in ipa_smp2p_modem_setup_ready_isr()
165 	mutex_unlock(&smp2p->mutex);  in ipa_smp2p_modem_setup_ready_isr()
174 	struct device *dev = &smp2p->ipa->pdev->dev;  in ipa_smp2p_irq_init()
178 	ret = platform_get_irq_byname(smp2p->ipa->pdev, name);  in ipa_smp2p_irq_init()
182 		return ret ? : -EINVAL;  in ipa_smp2p_irq_init()
200 /* Drop the clock reference if it was taken in ipa_smp2p_notify() */
201 static void ipa_smp2p_clock_release(struct ipa *ipa)  in ipa_smp2p_clock_release()  argument
203 	if (!ipa->smp2p->clock_on)  in ipa_smp2p_clock_release()
206 	ipa_clock_put(ipa);  in ipa_smp2p_clock_release()
207 	ipa->smp2p->clock_on = false;  in ipa_smp2p_clock_release()
210 /* Initialize the IPA SMP2P subsystem */
211 int ipa_smp2p_init(struct ipa *ipa, bool modem_init)  in ipa_smp2p_init()  argument
214 	struct device *dev = &ipa->pdev->dev;  in ipa_smp2p_init()
221 	valid_state = qcom_smem_state_get(dev, "ipa-clock-enabled-valid",  in ipa_smp2p_init()
226 		return -EINVAL;  in ipa_smp2p_init()
228 	enabled_state = qcom_smem_state_get(dev, "ipa-clock-enabled",  in ipa_smp2p_init()
233 		return -EINVAL;  in ipa_smp2p_init()
237 		return -ENOMEM;  in ipa_smp2p_init()
239 	smp2p->ipa = ipa;  in ipa_smp2p_init()
241 	/* These fields are needed by the clock query interrupt  in ipa_smp2p_init()
244 	mutex_init(&smp2p->mutex);  in ipa_smp2p_init()
245 	smp2p->valid_state = valid_state;  in ipa_smp2p_init()
246 	smp2p->valid_bit = valid_bit;  in ipa_smp2p_init()
247 	smp2p->enabled_state = enabled_state;  in ipa_smp2p_init()
248 	smp2p->enabled_bit = enabled_bit;  in ipa_smp2p_init()
251 	ipa->smp2p = smp2p;  in ipa_smp2p_init()
253 	ret = ipa_smp2p_irq_init(smp2p, "ipa-clock-query",  in ipa_smp2p_init()
257 	smp2p->clock_query_irq = ret;  in ipa_smp2p_init()
264 		/* Result will be non-zero (negative for error) */  in ipa_smp2p_init()
265 		ret = ipa_smp2p_irq_init(smp2p, "ipa-setup-ready",  in ipa_smp2p_init()
269 		smp2p->setup_ready_irq = ret;  in ipa_smp2p_init()
277 	ipa_smp2p_irq_exit(smp2p, smp2p->clock_query_irq);  in ipa_smp2p_init()
279 	ipa->smp2p = NULL;  in ipa_smp2p_init()
280 	mutex_destroy(&smp2p->mutex);  in ipa_smp2p_init()
286 void ipa_smp2p_exit(struct ipa *ipa)  in ipa_smp2p_exit()  argument
288 	struct ipa_smp2p *smp2p = ipa->smp2p;  in ipa_smp2p_exit()
290 	if (smp2p->setup_ready_irq)  in ipa_smp2p_exit()
291 		ipa_smp2p_irq_exit(smp2p, smp2p->setup_ready_irq);  in ipa_smp2p_exit()
293 	ipa_smp2p_irq_exit(smp2p, smp2p->clock_query_irq);  in ipa_smp2p_exit()
294 	/* We won't get notified any more; drop clock reference (if any) */  in ipa_smp2p_exit()
295 	ipa_smp2p_clock_release(ipa);  in ipa_smp2p_exit()
296 	ipa->smp2p = NULL;  in ipa_smp2p_exit()
297 	mutex_destroy(&smp2p->mutex);  in ipa_smp2p_exit()
301 void ipa_smp2p_disable(struct ipa *ipa)  in ipa_smp2p_disable()  argument
303 	struct ipa_smp2p *smp2p = ipa->smp2p;  in ipa_smp2p_disable()
305 	if (!smp2p->setup_ready_irq)  in ipa_smp2p_disable()
308 	mutex_lock(&smp2p->mutex);  in ipa_smp2p_disable()
310 	smp2p->disabled = true;  in ipa_smp2p_disable()
312 	mutex_unlock(&smp2p->mutex);  in ipa_smp2p_disable()
316 void ipa_smp2p_notify_reset(struct ipa *ipa)  in ipa_smp2p_notify_reset()  argument
318 	struct ipa_smp2p *smp2p = ipa->smp2p;  in ipa_smp2p_notify_reset()
321 	if (!smp2p->notified)  in ipa_smp2p_notify_reset()
324 	ipa_smp2p_clock_release(ipa);  in ipa_smp2p_notify_reset()
326 	/* Reset the clock enabled valid flag */  in ipa_smp2p_notify_reset()
327 	mask = BIT(smp2p->valid_bit);  in ipa_smp2p_notify_reset()
328 	qcom_smem_state_update_bits(smp2p->valid_state, mask, 0);  in ipa_smp2p_notify_reset()
330 	/* Mark the clock disabled for good measure... */  in ipa_smp2p_notify_reset()
331 	mask = BIT(smp2p->enabled_bit);  in ipa_smp2p_notify_reset()
332 	qcom_smem_state_update_bits(smp2p->enabled_state, mask, 0);  in ipa_smp2p_notify_reset()
334 	smp2p->notified = false;  in ipa_smp2p_notify_reset()