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git.proxmox.com Git - mirror_ubuntu-jammy-kernel.git/blob - drivers/net/ipa/ipa_power.c
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1 // SPDX-License-Identifier: GPL-2.0
3 /* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved.
4 * Copyright (C) 2018-2021 Linaro Ltd.
8 #include <linux/device.h>
9 #include <linux/interconnect.h>
11 #include <linux/pm_runtime.h>
12 #include <linux/bitops.h>
15 #include "ipa_power.h"
16 #include "ipa_endpoint.h"
17 #include "ipa_modem.h"
21 * DOC: IPA Power Management
23 * The IPA hardware is enabled when the IPA core clock and all the
24 * interconnects (buses) it depends on are enabled. Runtime power
25 * management is used to determine whether the core clock and
26 * interconnects are enabled, and if not in use to be suspended
29 * The core clock currently runs at a fixed clock rate when enabled,
30 * an all interconnects use a fixed average and peak bandwidth.
33 #define IPA_AUTOSUSPEND_DELAY 500 /* milliseconds */
36 * struct ipa_interconnect - IPA interconnect information
37 * @path: Interconnect path
38 * @average_bandwidth: Average interconnect bandwidth (KB/second)
39 * @peak_bandwidth: Peak interconnect bandwidth (KB/second)
41 struct ipa_interconnect
{
42 struct icc_path
*path
;
43 u32 average_bandwidth
;
48 * enum ipa_power_flag - IPA power flags
49 * @IPA_POWER_FLAG_RESUMED: Whether resume from suspend has been signaled
50 * @IPA_POWER_FLAG_SYSTEM: Hardware is system (not runtime) suspended
51 * @IPA_POWER_FLAG_STOPPED: Modem TX is disabled by ipa_start_xmit()
52 * @IPA_POWER_FLAG_STARTED: Modem TX was enabled by ipa_runtime_resume()
53 * @IPA_POWER_FLAG_COUNT: Number of defined power flags
56 IPA_POWER_FLAG_RESUMED
,
57 IPA_POWER_FLAG_SYSTEM
,
58 IPA_POWER_FLAG_STOPPED
,
59 IPA_POWER_FLAG_STARTED
,
60 IPA_POWER_FLAG_COUNT
, /* Last; not a flag */
64 * struct ipa_power - IPA power management information
65 * @dev: IPA device pointer
66 * @core: IPA core clock
67 * @spinlock: Protects modem TX queue enable/disable
68 * @flags: Boolean state flags
69 * @interconnect_count: Number of elements in interconnect[]
70 * @interconnect: Interconnect array
75 spinlock_t spinlock
; /* used with STOPPED/STARTED power flags */
76 DECLARE_BITMAP(flags
, IPA_POWER_FLAG_COUNT
);
77 u32 interconnect_count
;
78 struct ipa_interconnect
*interconnect
;
81 static int ipa_interconnect_init_one(struct device
*dev
,
82 struct ipa_interconnect
*interconnect
,
83 const struct ipa_interconnect_data
*data
)
85 struct icc_path
*path
;
87 path
= of_icc_get(dev
, data
->name
);
89 int ret
= PTR_ERR(path
);
91 dev_err_probe(dev
, ret
, "error getting %s interconnect\n",
97 interconnect
->path
= path
;
98 interconnect
->average_bandwidth
= data
->average_bandwidth
;
99 interconnect
->peak_bandwidth
= data
->peak_bandwidth
;
104 static void ipa_interconnect_exit_one(struct ipa_interconnect
*interconnect
)
106 icc_put(interconnect
->path
);
107 memset(interconnect
, 0, sizeof(*interconnect
));
110 /* Initialize interconnects required for IPA operation */
111 static int ipa_interconnect_init(struct ipa_power
*power
, struct device
*dev
,
112 const struct ipa_interconnect_data
*data
)
114 struct ipa_interconnect
*interconnect
;
118 count
= power
->interconnect_count
;
119 interconnect
= kcalloc(count
, sizeof(*interconnect
), GFP_KERNEL
);
122 power
->interconnect
= interconnect
;
125 ret
= ipa_interconnect_init_one(dev
, interconnect
, data
++);
134 while (interconnect
-- > power
->interconnect
)
135 ipa_interconnect_exit_one(interconnect
);
136 kfree(power
->interconnect
);
137 power
->interconnect
= NULL
;
142 /* Inverse of ipa_interconnect_init() */
143 static void ipa_interconnect_exit(struct ipa_power
*power
)
145 struct ipa_interconnect
*interconnect
;
147 interconnect
= power
->interconnect
+ power
->interconnect_count
;
148 while (interconnect
-- > power
->interconnect
)
149 ipa_interconnect_exit_one(interconnect
);
150 kfree(power
->interconnect
);
151 power
->interconnect
= NULL
;
154 /* Currently we only use one bandwidth level, so just "enable" interconnects */
155 static int ipa_interconnect_enable(struct ipa
*ipa
)
157 struct ipa_interconnect
*interconnect
;
158 struct ipa_power
*power
= ipa
->power
;
162 interconnect
= power
->interconnect
;
163 for (i
= 0; i
< power
->interconnect_count
; i
++) {
164 ret
= icc_set_bw(interconnect
->path
,
165 interconnect
->average_bandwidth
,
166 interconnect
->peak_bandwidth
);
168 dev_err(&ipa
->pdev
->dev
,
169 "error %d enabling %s interconnect\n",
170 ret
, icc_get_name(interconnect
->path
));
179 while (interconnect
-- > power
->interconnect
)
180 (void)icc_set_bw(interconnect
->path
, 0, 0);
185 /* To disable an interconnect, we just its bandwidth to 0 */
186 static int ipa_interconnect_disable(struct ipa
*ipa
)
188 struct ipa_interconnect
*interconnect
;
189 struct ipa_power
*power
= ipa
->power
;
190 struct device
*dev
= &ipa
->pdev
->dev
;
195 count
= power
->interconnect_count
;
196 interconnect
= power
->interconnect
+ count
;
199 ret
= icc_set_bw(interconnect
->path
, 0, 0);
201 dev_err(dev
, "error %d disabling %s interconnect\n",
202 ret
, icc_get_name(interconnect
->path
));
203 /* Try to disable all; record only the first error */
212 /* Enable IPA power, enabling interconnects and the core clock */
213 static int ipa_power_enable(struct ipa
*ipa
)
217 ret
= ipa_interconnect_enable(ipa
);
221 ret
= clk_prepare_enable(ipa
->power
->core
);
223 dev_err(&ipa
->pdev
->dev
, "error %d enabling core clock\n", ret
);
224 (void)ipa_interconnect_disable(ipa
);
230 /* Inverse of ipa_power_enable() */
231 static int ipa_power_disable(struct ipa
*ipa
)
233 clk_disable_unprepare(ipa
->power
->core
);
235 return ipa_interconnect_disable(ipa
);
238 static int ipa_runtime_suspend(struct device
*dev
)
240 struct ipa
*ipa
= dev_get_drvdata(dev
);
242 /* Endpoints aren't usable until setup is complete */
243 if (ipa
->setup_complete
) {
244 __clear_bit(IPA_POWER_FLAG_RESUMED
, ipa
->power
->flags
);
245 ipa_endpoint_suspend(ipa
);
246 gsi_suspend(&ipa
->gsi
);
249 return ipa_power_disable(ipa
);
252 static int ipa_runtime_resume(struct device
*dev
)
254 struct ipa
*ipa
= dev_get_drvdata(dev
);
257 ret
= ipa_power_enable(ipa
);
258 if (WARN_ON(ret
< 0))
261 /* Endpoints aren't usable until setup is complete */
262 if (ipa
->setup_complete
) {
263 gsi_resume(&ipa
->gsi
);
264 ipa_endpoint_resume(ipa
);
270 static int ipa_suspend(struct device
*dev
)
272 struct ipa
*ipa
= dev_get_drvdata(dev
);
274 __set_bit(IPA_POWER_FLAG_SYSTEM
, ipa
->power
->flags
);
276 return pm_runtime_force_suspend(dev
);
279 static int ipa_resume(struct device
*dev
)
281 struct ipa
*ipa
= dev_get_drvdata(dev
);
284 ret
= pm_runtime_force_resume(dev
);
286 __clear_bit(IPA_POWER_FLAG_SYSTEM
, ipa
->power
->flags
);
291 /* Return the current IPA core clock rate */
292 u32
ipa_core_clock_rate(struct ipa
*ipa
)
294 return ipa
->power
? (u32
)clk_get_rate(ipa
->power
->core
) : 0;
298 * ipa_suspend_handler() - Handle the suspend IPA interrupt
300 * @irq_id: IPA interrupt type (unused)
302 * If an RX endpoint is suspended, and the IPA has a packet destined for
303 * that endpoint, the IPA generates a SUSPEND interrupt to inform the AP
304 * that it should resume the endpoint. If we get one of these interrupts
305 * we just wake up the system.
307 static void ipa_suspend_handler(struct ipa
*ipa
, enum ipa_irq_id irq_id
)
309 /* To handle an IPA interrupt we will have resumed the hardware
310 * just to handle the interrupt, so we're done. If we are in a
311 * system suspend, trigger a system resume.
313 if (!__test_and_set_bit(IPA_POWER_FLAG_RESUMED
, ipa
->power
->flags
))
314 if (test_bit(IPA_POWER_FLAG_SYSTEM
, ipa
->power
->flags
))
315 pm_wakeup_dev_event(&ipa
->pdev
->dev
, 0, true);
317 /* Acknowledge/clear the suspend interrupt on all endpoints */
318 ipa_interrupt_suspend_clear_all(ipa
->interrupt
);
321 /* The next few functions coordinate stopping and starting the modem
322 * network device transmit queue.
324 * Transmit can be running concurrent with power resume, and there's a
325 * chance the resume completes before the transmit path stops the queue,
326 * leaving the queue in a stopped state. The next two functions are used
327 * to avoid this: ipa_power_modem_queue_stop() is used by ipa_start_xmit()
328 * to conditionally stop the TX queue; and ipa_power_modem_queue_start()
329 * is used by ipa_runtime_resume() to conditionally restart it.
331 * Two flags and a spinlock are used. If the queue is stopped, the STOPPED
332 * power flag is set. And if the queue is started, the STARTED flag is set.
333 * The queue is only started on resume if the STOPPED flag is set. And the
334 * queue is only started in ipa_start_xmit() if the STARTED flag is *not*
335 * set. As a result, the queue remains operational if the two activites
336 * happen concurrently regardless of the order they complete. The spinlock
337 * ensures the flag and TX queue operations are done atomically.
339 * The first function stops the modem netdev transmit queue, but only if
340 * the STARTED flag is *not* set. That flag is cleared if it was set.
341 * If the queue is stopped, the STOPPED flag is set. This is called only
342 * from the power ->runtime_resume operation.
344 void ipa_power_modem_queue_stop(struct ipa
*ipa
)
346 struct ipa_power
*power
= ipa
->power
;
349 spin_lock_irqsave(&power
->spinlock
, flags
);
351 if (!__test_and_clear_bit(IPA_POWER_FLAG_STARTED
, power
->flags
)) {
352 netif_stop_queue(ipa
->modem_netdev
);
353 __set_bit(IPA_POWER_FLAG_STOPPED
, power
->flags
);
356 spin_unlock_irqrestore(&power
->spinlock
, flags
);
359 /* This function starts the modem netdev transmit queue, but only if the
360 * STOPPED flag is set. That flag is cleared if it was set. If the queue
361 * was restarted, the STARTED flag is set; this allows ipa_start_xmit()
362 * to skip stopping the queue in the event of a race.
364 void ipa_power_modem_queue_wake(struct ipa
*ipa
)
366 struct ipa_power
*power
= ipa
->power
;
369 spin_lock_irqsave(&power
->spinlock
, flags
);
371 if (__test_and_clear_bit(IPA_POWER_FLAG_STOPPED
, power
->flags
)) {
372 __set_bit(IPA_POWER_FLAG_STARTED
, power
->flags
);
373 netif_wake_queue(ipa
->modem_netdev
);
376 spin_unlock_irqrestore(&power
->spinlock
, flags
);
379 /* This function clears the STARTED flag once the TX queue is operating */
380 void ipa_power_modem_queue_active(struct ipa
*ipa
)
382 clear_bit(IPA_POWER_FLAG_STARTED
, ipa
->power
->flags
);
385 int ipa_power_setup(struct ipa
*ipa
)
389 ipa_interrupt_add(ipa
->interrupt
, IPA_IRQ_TX_SUSPEND
,
390 ipa_suspend_handler
);
392 ret
= device_init_wakeup(&ipa
->pdev
->dev
, true);
394 ipa_interrupt_remove(ipa
->interrupt
, IPA_IRQ_TX_SUSPEND
);
399 void ipa_power_teardown(struct ipa
*ipa
)
401 (void)device_init_wakeup(&ipa
->pdev
->dev
, false);
402 ipa_interrupt_remove(ipa
->interrupt
, IPA_IRQ_TX_SUSPEND
);
405 /* Initialize IPA power management */
407 ipa_power_init(struct device
*dev
, const struct ipa_power_data
*data
)
409 struct ipa_power
*power
;
413 clk
= clk_get(dev
, "core");
415 dev_err_probe(dev
, PTR_ERR(clk
), "error getting core clock\n");
417 return ERR_CAST(clk
);
420 ret
= clk_set_rate(clk
, data
->core_clock_rate
);
422 dev_err(dev
, "error %d setting core clock rate to %u\n",
423 ret
, data
->core_clock_rate
);
427 power
= kzalloc(sizeof(*power
), GFP_KERNEL
);
434 spin_lock_init(&power
->spinlock
);
435 power
->interconnect_count
= data
->interconnect_count
;
437 ret
= ipa_interconnect_init(power
, dev
, data
->interconnect_data
);
441 pm_runtime_set_autosuspend_delay(dev
, IPA_AUTOSUSPEND_DELAY
);
442 pm_runtime_use_autosuspend(dev
);
443 pm_runtime_enable(dev
);
455 /* Inverse of ipa_power_init() */
456 void ipa_power_exit(struct ipa_power
*power
)
458 struct device
*dev
= power
->dev
;
459 struct clk
*clk
= power
->core
;
461 pm_runtime_disable(dev
);
462 pm_runtime_dont_use_autosuspend(dev
);
463 ipa_interconnect_exit(power
);
468 const struct dev_pm_ops ipa_pm_ops
= {
469 .suspend
= ipa_suspend
,
470 .resume
= ipa_resume
,
471 .runtime_suspend
= ipa_runtime_suspend
,
472 .runtime_resume
= ipa_runtime_resume
,