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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/net/ipa/ipa_power.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/net/ipa/ipa_power.c')
-rw-r--r-- | drivers/net/ipa/ipa_power.c | 448 |
1 files changed, 448 insertions, 0 deletions
diff --git a/drivers/net/ipa/ipa_power.c b/drivers/net/ipa/ipa_power.c new file mode 100644 index 000000000..8057be8cd --- /dev/null +++ b/drivers/net/ipa/ipa_power.c @@ -0,0 +1,448 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved. + * Copyright (C) 2018-2022 Linaro Ltd. + */ + +#include <linux/clk.h> +#include <linux/device.h> +#include <linux/interconnect.h> +#include <linux/pm.h> +#include <linux/pm_runtime.h> +#include <linux/bitops.h> + +#include "linux/soc/qcom/qcom_aoss.h" + +#include "ipa.h" +#include "ipa_power.h" +#include "ipa_endpoint.h" +#include "ipa_modem.h" +#include "ipa_data.h" + +/** + * DOC: IPA Power Management + * + * The IPA hardware is enabled when the IPA core clock and all the + * interconnects (buses) it depends on are enabled. Runtime power + * management is used to determine whether the core clock and + * interconnects are enabled, and if not in use to be suspended + * automatically. + * + * The core clock currently runs at a fixed clock rate when enabled, + * an all interconnects use a fixed average and peak bandwidth. + */ + +#define IPA_AUTOSUSPEND_DELAY 500 /* milliseconds */ + +/** + * enum ipa_power_flag - IPA power flags + * @IPA_POWER_FLAG_RESUMED: Whether resume from suspend has been signaled + * @IPA_POWER_FLAG_SYSTEM: Hardware is system (not runtime) suspended + * @IPA_POWER_FLAG_STOPPED: Modem TX is disabled by ipa_start_xmit() + * @IPA_POWER_FLAG_STARTED: Modem TX was enabled by ipa_runtime_resume() + * @IPA_POWER_FLAG_COUNT: Number of defined power flags + */ +enum ipa_power_flag { + IPA_POWER_FLAG_RESUMED, + IPA_POWER_FLAG_SYSTEM, + IPA_POWER_FLAG_STOPPED, + IPA_POWER_FLAG_STARTED, + IPA_POWER_FLAG_COUNT, /* Last; not a flag */ +}; + +/** + * struct ipa_power - IPA power management information + * @dev: IPA device pointer + * @core: IPA core clock + * @qmp: QMP handle for AOSS communication + * @spinlock: Protects modem TX queue enable/disable + * @flags: Boolean state flags + * @interconnect_count: Number of elements in interconnect[] + * @interconnect: Interconnect array + */ +struct ipa_power { + struct device *dev; + struct clk *core; + struct qmp *qmp; + spinlock_t spinlock; /* used with STOPPED/STARTED power flags */ + DECLARE_BITMAP(flags, IPA_POWER_FLAG_COUNT); + u32 interconnect_count; + struct icc_bulk_data interconnect[]; +}; + +/* Initialize interconnects required for IPA operation */ +static int ipa_interconnect_init(struct ipa_power *power, + const struct ipa_interconnect_data *data) +{ + struct icc_bulk_data *interconnect; + int ret; + u32 i; + + /* Initialize our interconnect data array for bulk operations */ + interconnect = &power->interconnect[0]; + for (i = 0; i < power->interconnect_count; i++) { + /* interconnect->path is filled in by of_icc_bulk_get() */ + interconnect->name = data->name; + interconnect->avg_bw = data->average_bandwidth; + interconnect->peak_bw = data->peak_bandwidth; + data++; + interconnect++; + } + + ret = of_icc_bulk_get(power->dev, power->interconnect_count, + power->interconnect); + if (ret) + return ret; + + /* All interconnects are initially disabled */ + icc_bulk_disable(power->interconnect_count, power->interconnect); + + /* Set the bandwidth values to be used when enabled */ + ret = icc_bulk_set_bw(power->interconnect_count, power->interconnect); + if (ret) + icc_bulk_put(power->interconnect_count, power->interconnect); + + return ret; +} + +/* Inverse of ipa_interconnect_init() */ +static void ipa_interconnect_exit(struct ipa_power *power) +{ + icc_bulk_put(power->interconnect_count, power->interconnect); +} + +/* Enable IPA power, enabling interconnects and the core clock */ +static int ipa_power_enable(struct ipa *ipa) +{ + struct ipa_power *power = ipa->power; + int ret; + + ret = icc_bulk_enable(power->interconnect_count, power->interconnect); + if (ret) + return ret; + + ret = clk_prepare_enable(power->core); + if (ret) { + dev_err(power->dev, "error %d enabling core clock\n", ret); + icc_bulk_disable(power->interconnect_count, + power->interconnect); + } + + return ret; +} + +/* Inverse of ipa_power_enable() */ +static void ipa_power_disable(struct ipa *ipa) +{ + struct ipa_power *power = ipa->power; + + clk_disable_unprepare(power->core); + + icc_bulk_disable(power->interconnect_count, power->interconnect); +} + +static int ipa_runtime_suspend(struct device *dev) +{ + struct ipa *ipa = dev_get_drvdata(dev); + + /* Endpoints aren't usable until setup is complete */ + if (ipa->setup_complete) { + __clear_bit(IPA_POWER_FLAG_RESUMED, ipa->power->flags); + ipa_endpoint_suspend(ipa); + gsi_suspend(&ipa->gsi); + } + + ipa_power_disable(ipa); + + return 0; +} + +static int ipa_runtime_resume(struct device *dev) +{ + struct ipa *ipa = dev_get_drvdata(dev); + int ret; + + ret = ipa_power_enable(ipa); + if (WARN_ON(ret < 0)) + return ret; + + /* Endpoints aren't usable until setup is complete */ + if (ipa->setup_complete) { + gsi_resume(&ipa->gsi); + ipa_endpoint_resume(ipa); + } + + return 0; +} + +static int ipa_suspend(struct device *dev) +{ + struct ipa *ipa = dev_get_drvdata(dev); + + __set_bit(IPA_POWER_FLAG_SYSTEM, ipa->power->flags); + + /* Increment the disable depth to ensure that the IRQ won't + * be re-enabled until the matching _enable call in + * ipa_resume(). We do this to ensure that the interrupt + * handler won't run whilst PM runtime is disabled. + * + * Note that disabling the IRQ is NOT the same as disabling + * irq wake. If wakeup is enabled for the IPA then the IRQ + * will still cause the system to wake up, see irq_set_irq_wake(). + */ + ipa_interrupt_irq_disable(ipa); + + return pm_runtime_force_suspend(dev); +} + +static int ipa_resume(struct device *dev) +{ + struct ipa *ipa = dev_get_drvdata(dev); + int ret; + + ret = pm_runtime_force_resume(dev); + + __clear_bit(IPA_POWER_FLAG_SYSTEM, ipa->power->flags); + + /* Now that PM runtime is enabled again it's safe + * to turn the IRQ back on and process any data + * that was received during suspend. + */ + ipa_interrupt_irq_enable(ipa); + + return ret; +} + +/* Return the current IPA core clock rate */ +u32 ipa_core_clock_rate(struct ipa *ipa) +{ + return ipa->power ? (u32)clk_get_rate(ipa->power->core) : 0; +} + +/** + * ipa_suspend_handler() - Handle the suspend IPA interrupt + * @ipa: IPA pointer + * @irq_id: IPA interrupt type (unused) + * + * If an RX endpoint is suspended, and the IPA has a packet destined for + * that endpoint, the IPA generates a SUSPEND interrupt to inform the AP + * that it should resume the endpoint. If we get one of these interrupts + * we just wake up the system. + */ +static void ipa_suspend_handler(struct ipa *ipa, enum ipa_irq_id irq_id) +{ + /* To handle an IPA interrupt we will have resumed the hardware + * just to handle the interrupt, so we're done. If we are in a + * system suspend, trigger a system resume. + */ + if (!__test_and_set_bit(IPA_POWER_FLAG_RESUMED, ipa->power->flags)) + if (test_bit(IPA_POWER_FLAG_SYSTEM, ipa->power->flags)) + pm_wakeup_dev_event(&ipa->pdev->dev, 0, true); + + /* Acknowledge/clear the suspend interrupt on all endpoints */ + ipa_interrupt_suspend_clear_all(ipa->interrupt); +} + +/* The next few functions coordinate stopping and starting the modem + * network device transmit queue. + * + * Transmit can be running concurrent with power resume, and there's a + * chance the resume completes before the transmit path stops the queue, + * leaving the queue in a stopped state. The next two functions are used + * to avoid this: ipa_power_modem_queue_stop() is used by ipa_start_xmit() + * to conditionally stop the TX queue; and ipa_power_modem_queue_start() + * is used by ipa_runtime_resume() to conditionally restart it. + * + * Two flags and a spinlock are used. If the queue is stopped, the STOPPED + * power flag is set. And if the queue is started, the STARTED flag is set. + * The queue is only started on resume if the STOPPED flag is set. And the + * queue is only started in ipa_start_xmit() if the STARTED flag is *not* + * set. As a result, the queue remains operational if the two activites + * happen concurrently regardless of the order they complete. The spinlock + * ensures the flag and TX queue operations are done atomically. + * + * The first function stops the modem netdev transmit queue, but only if + * the STARTED flag is *not* set. That flag is cleared if it was set. + * If the queue is stopped, the STOPPED flag is set. This is called only + * from the power ->runtime_resume operation. + */ +void ipa_power_modem_queue_stop(struct ipa *ipa) +{ + struct ipa_power *power = ipa->power; + unsigned long flags; + + spin_lock_irqsave(&power->spinlock, flags); + + if (!__test_and_clear_bit(IPA_POWER_FLAG_STARTED, power->flags)) { + netif_stop_queue(ipa->modem_netdev); + __set_bit(IPA_POWER_FLAG_STOPPED, power->flags); + } + + spin_unlock_irqrestore(&power->spinlock, flags); +} + +/* This function starts the modem netdev transmit queue, but only if the + * STOPPED flag is set. That flag is cleared if it was set. If the queue + * was restarted, the STARTED flag is set; this allows ipa_start_xmit() + * to skip stopping the queue in the event of a race. + */ +void ipa_power_modem_queue_wake(struct ipa *ipa) +{ + struct ipa_power *power = ipa->power; + unsigned long flags; + + spin_lock_irqsave(&power->spinlock, flags); + + if (__test_and_clear_bit(IPA_POWER_FLAG_STOPPED, power->flags)) { + __set_bit(IPA_POWER_FLAG_STARTED, power->flags); + netif_wake_queue(ipa->modem_netdev); + } + + spin_unlock_irqrestore(&power->spinlock, flags); +} + +/* This function clears the STARTED flag once the TX queue is operating */ +void ipa_power_modem_queue_active(struct ipa *ipa) +{ + clear_bit(IPA_POWER_FLAG_STARTED, ipa->power->flags); +} + +static int ipa_power_retention_init(struct ipa_power *power) +{ + struct qmp *qmp = qmp_get(power->dev); + + if (IS_ERR(qmp)) { + if (PTR_ERR(qmp) == -EPROBE_DEFER) + return -EPROBE_DEFER; + + /* We assume any other error means it's not defined/needed */ + qmp = NULL; + } + power->qmp = qmp; + + return 0; +} + +static void ipa_power_retention_exit(struct ipa_power *power) +{ + qmp_put(power->qmp); + power->qmp = NULL; +} + +/* Control register retention on power collapse */ +void ipa_power_retention(struct ipa *ipa, bool enable) +{ + static const char fmt[] = "{ class: bcm, res: ipa_pc, val: %c }"; + struct ipa_power *power = ipa->power; + char buf[36]; /* Exactly enough for fmt[]; size a multiple of 4 */ + int ret; + + if (!power->qmp) + return; /* Not needed on this platform */ + + (void)snprintf(buf, sizeof(buf), fmt, enable ? '1' : '0'); + + ret = qmp_send(power->qmp, buf, sizeof(buf)); + if (ret) + dev_err(power->dev, "error %d sending QMP %sable request\n", + ret, enable ? "en" : "dis"); +} + +int ipa_power_setup(struct ipa *ipa) +{ + int ret; + + ipa_interrupt_add(ipa->interrupt, IPA_IRQ_TX_SUSPEND, + ipa_suspend_handler); + + ret = device_init_wakeup(&ipa->pdev->dev, true); + if (ret) + ipa_interrupt_remove(ipa->interrupt, IPA_IRQ_TX_SUSPEND); + + return ret; +} + +void ipa_power_teardown(struct ipa *ipa) +{ + (void)device_init_wakeup(&ipa->pdev->dev, false); + ipa_interrupt_remove(ipa->interrupt, IPA_IRQ_TX_SUSPEND); +} + +/* Initialize IPA power management */ +struct ipa_power * +ipa_power_init(struct device *dev, const struct ipa_power_data *data) +{ + struct ipa_power *power; + struct clk *clk; + size_t size; + int ret; + + clk = clk_get(dev, "core"); + if (IS_ERR(clk)) { + dev_err_probe(dev, PTR_ERR(clk), "error getting core clock\n"); + + return ERR_CAST(clk); + } + + ret = clk_set_rate(clk, data->core_clock_rate); + if (ret) { + dev_err(dev, "error %d setting core clock rate to %u\n", + ret, data->core_clock_rate); + goto err_clk_put; + } + + size = struct_size(power, interconnect, data->interconnect_count); + power = kzalloc(size, GFP_KERNEL); + if (!power) { + ret = -ENOMEM; + goto err_clk_put; + } + power->dev = dev; + power->core = clk; + spin_lock_init(&power->spinlock); + power->interconnect_count = data->interconnect_count; + + ret = ipa_interconnect_init(power, data->interconnect_data); + if (ret) + goto err_kfree; + + ret = ipa_power_retention_init(power); + if (ret) + goto err_interconnect_exit; + + pm_runtime_set_autosuspend_delay(dev, IPA_AUTOSUSPEND_DELAY); + pm_runtime_use_autosuspend(dev); + pm_runtime_enable(dev); + + return power; + +err_interconnect_exit: + ipa_interconnect_exit(power); +err_kfree: + kfree(power); +err_clk_put: + clk_put(clk); + + return ERR_PTR(ret); +} + +/* Inverse of ipa_power_init() */ +void ipa_power_exit(struct ipa_power *power) +{ + struct device *dev = power->dev; + struct clk *clk = power->core; + + pm_runtime_disable(dev); + pm_runtime_dont_use_autosuspend(dev); + ipa_power_retention_exit(power); + ipa_interconnect_exit(power); + kfree(power); + clk_put(clk); +} + +const struct dev_pm_ops ipa_pm_ops = { + .suspend = ipa_suspend, + .resume = ipa_resume, + .runtime_suspend = ipa_runtime_suspend, + .runtime_resume = ipa_runtime_resume, +}; |