net: ipa: use runtime PM core

Use the runtime power management core to cause hardware suspend and
resume to occur.  Enable it in ipa_clock_init() (without autosuspend),
and disable it in ipa_clock_exit().

Use ipa_runtime_suspend() as the ->runtime_suspend power operation,
and arrange for it to be called by having ipa_clock_get() call
pm_runtime_get_sync() when the first clock reference is taken.
Similarly, use ipa_runtime_resume() as the ->runtime_resume power
operation, and pm_runtime_put() when the last IPA clock reference
is dropped.

Introduce ipa_runtime_idle() as the ->runtime_idle power operation,
and have it return a non-zero value; this way suspend will never
occur except when forced.

Use pm_runtime_force_suspend() and pm_runtime_force_resume() as the
system suspend and resume callbacks, and remove ipa_suspend() and
ipa_resume().

Store a pointer to the device structure passed to ipa_clock_init(),
so it can be used by ipa_clock_exit() to disable runtime power
management.

For now we preserve IPA clock reference counting.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Alex Elder 2021-08-10 14:27:01 -05:00 committed by David S. Miller
parent 2abb0c7f98
commit 63de79f031

View File

@ -60,6 +60,7 @@ enum ipa_power_flag {
* struct ipa_clock - IPA clocking information
* @count: Clocking reference count
* @mutex: Protects clock enable/disable
* @dev: IPA device pointer
* @core: IPA core clock
* @flags: Boolean state flags
* @interconnect_count: Number of elements in interconnect[]
@ -68,6 +69,7 @@ enum ipa_power_flag {
struct ipa_clock {
refcount_t count;
struct mutex mutex; /* protects clock enable/disable */
struct device *dev;
struct clk *core;
DECLARE_BITMAP(flags, IPA_POWER_FLAG_COUNT);
u32 interconnect_count;
@ -263,13 +265,29 @@ static int ipa_runtime_resume(struct device *dev)
return 0;
}
static int ipa_runtime_idle(struct device *dev)
{
return -EAGAIN;
}
/* Get an IPA clock reference, but only if the reference count is
* already non-zero. Returns true if the additional reference was
* added successfully, or false otherwise.
*/
bool ipa_clock_get_additional(struct ipa *ipa)
{
return refcount_inc_not_zero(&ipa->clock->count);
struct device *dev;
int ret;
if (!refcount_inc_not_zero(&ipa->clock->count))
return false;
dev = &ipa->pdev->dev;
ret = pm_runtime_get_sync(dev);
if (ret < 0)
dev_err(dev, "error %d enabling power\n", ret);
return true;
}
/* Get an IPA clock reference. If the reference count is non-zero, it is
@ -283,6 +301,7 @@ bool ipa_clock_get_additional(struct ipa *ipa)
int ipa_clock_get(struct ipa *ipa)
{
struct ipa_clock *clock = ipa->clock;
struct device *dev;
int ret;
/* If the clock is running, just bump the reference count */
@ -298,7 +317,8 @@ int ipa_clock_get(struct ipa *ipa)
goto out_mutex_unlock;
}
ret = ipa_runtime_resume(&ipa->pdev->dev);
dev = &ipa->pdev->dev;
ret = pm_runtime_get_sync(dev);
refcount_set(&clock->count, 1);
@ -313,14 +333,17 @@ out_mutex_unlock:
*/
int ipa_clock_put(struct ipa *ipa)
{
struct device *dev = &ipa->pdev->dev;
struct ipa_clock *clock = ipa->clock;
int last;
int ret;
/* If this is not the last reference there's nothing more to do */
if (!refcount_dec_and_mutex_lock(&clock->count, &clock->mutex))
return 0;
last = refcount_dec_and_mutex_lock(&clock->count, &clock->mutex);
ret = ipa_runtime_suspend(&ipa->pdev->dev);
ret = pm_runtime_put(dev);
if (!last)
return ret;
mutex_unlock(&clock->mutex);
@ -394,6 +417,7 @@ ipa_clock_init(struct device *dev, const struct ipa_clock_data *data)
ret = -ENOMEM;
goto err_clk_put;
}
clock->dev = dev;
clock->core = clk;
clock->interconnect_count = data->interconnect_count;
@ -404,6 +428,9 @@ ipa_clock_init(struct device *dev, const struct ipa_clock_data *data)
mutex_init(&clock->mutex);
refcount_set(&clock->count, 0);
pm_runtime_dont_use_autosuspend(dev);
pm_runtime_enable(dev);
return clock;
err_kfree:
@ -420,43 +447,17 @@ void ipa_clock_exit(struct ipa_clock *clock)
struct clk *clk = clock->core;
WARN_ON(refcount_read(&clock->count) != 0);
pm_runtime_disable(clock->dev);
mutex_destroy(&clock->mutex);
ipa_interconnect_exit(clock);
kfree(clock);
clk_put(clk);
}
/**
* ipa_suspend() - Power management system suspend callback
* @dev: IPA device structure
*
* Return: 0 on success, or a negative error code
*
* Called by the PM framework when a system suspend operation is invoked.
* Suspends endpoints and releases the clock reference held to keep
* the IPA clock running until this point.
*/
static int ipa_suspend(struct device *dev)
{
return ipa_runtime_suspend(dev);
}
/**
* ipa_resume() - Power management system resume callback
* @dev: IPA device structure
*
* Return: 0 on success, or a negative error code
*
* Called by the PM framework when a system resume operation is invoked.
* Takes an IPA clock reference to keep the clock running until suspend,
* and resumes endpoints.
*/
static int ipa_resume(struct device *dev)
{
return ipa_runtime_resume(dev);
}
const struct dev_pm_ops ipa_pm_ops = {
.suspend = ipa_suspend,
.resume = ipa_resume,
.suspend = pm_runtime_force_suspend,
.resume = pm_runtime_force_resume,
.runtime_suspend = ipa_runtime_suspend,
.runtime_resume = ipa_runtime_resume,
.runtime_idle = ipa_runtime_idle,
};