Skip to content

Commit

Permalink
drm/i915: protect RPS/RC6 related accesses (including PCU) with a new…
Browse files Browse the repository at this point in the history 
… mutex

This allows the power related code to run independently of the rest of
the pipeline, extending the resume and init time improvements into
userspace, which would otherwise have been blocked on the struct mutex
if we were doing PCU communication.

v2: Also convert the locking for the rps sysfs interface.

Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> (v1)
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
  • Loading branch information
Jesse Barnes authored and Daniel Vetter committed Nov 11, 2012
1 parent 1a01ab3 commit 4fc688c
Show file tree
Hide file tree
Showing 6 changed files with 41 additions and 44 deletions.
20 changes: 10 additions & 10 deletions drivers/gpu/drm/i915/i915_debugfs.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1280,7 +1280,7 @@ static int i915_ring_freq_table(struct seq_file *m, void *unused)
return 0;
}

ret = mutex_lock_interruptible(&dev->struct_mutex);
ret = mutex_lock_interruptible(&dev_priv->rps.hw_lock);
if (ret)
return ret;

Expand All @@ -1296,7 +1296,7 @@ static int i915_ring_freq_table(struct seq_file *m, void *unused)
seq_printf(m, "%d\t\t%d\n", gpu_freq * GT_FREQUENCY_MULTIPLIER, ia_freq * 100);
}

mutex_unlock(&dev->struct_mutex);
mutex_unlock(&dev_priv->rps.hw_lock);

return 0;
}
Expand Down Expand Up @@ -1713,13 +1713,13 @@ i915_max_freq_read(struct file *filp,
if (!(IS_GEN6(dev) || IS_GEN7(dev)))
return -ENODEV;

ret = mutex_lock_interruptible(&dev->struct_mutex);
ret = mutex_lock_interruptible(&dev_priv->rps.hw_lock);
if (ret)
return ret;

len = snprintf(buf, sizeof(buf),
"max freq: %d\n", dev_priv->rps.max_delay * GT_FREQUENCY_MULTIPLIER);
mutex_unlock(&dev->struct_mutex);
mutex_unlock(&dev_priv->rps.hw_lock);

if (len > sizeof(buf))
len = sizeof(buf);
Expand Down Expand Up @@ -1754,7 +1754,7 @@ i915_max_freq_write(struct file *filp,

DRM_DEBUG_DRIVER("Manually setting max freq to %d\n", val);

ret = mutex_lock_interruptible(&dev->struct_mutex);
ret = mutex_lock_interruptible(&dev_priv->rps.hw_lock);
if (ret)
return ret;

Expand All @@ -1764,7 +1764,7 @@ i915_max_freq_write(struct file *filp,
dev_priv->rps.max_delay = val / GT_FREQUENCY_MULTIPLIER;

gen6_set_rps(dev, val / GT_FREQUENCY_MULTIPLIER);
mutex_unlock(&dev->struct_mutex);
mutex_unlock(&dev_priv->rps.hw_lock);

return cnt;
}
Expand All @@ -1789,13 +1789,13 @@ i915_min_freq_read(struct file *filp, char __user *ubuf, size_t max,
if (!(IS_GEN6(dev) || IS_GEN7(dev)))
return -ENODEV;

ret = mutex_lock_interruptible(&dev->struct_mutex);
ret = mutex_lock_interruptible(&dev_priv->rps.hw_lock);
if (ret)
return ret;

len = snprintf(buf, sizeof(buf),
"min freq: %d\n", dev_priv->rps.min_delay * GT_FREQUENCY_MULTIPLIER);
mutex_unlock(&dev->struct_mutex);
mutex_unlock(&dev_priv->rps.hw_lock);

if (len > sizeof(buf))
len = sizeof(buf);
Expand Down Expand Up @@ -1828,7 +1828,7 @@ i915_min_freq_write(struct file *filp, const char __user *ubuf, size_t cnt,

DRM_DEBUG_DRIVER("Manually setting min freq to %d\n", val);

ret = mutex_lock_interruptible(&dev->struct_mutex);
ret = mutex_lock_interruptible(&dev_priv->rps.hw_lock);
if (ret)
return ret;

Expand All @@ -1838,7 +1838,7 @@ i915_min_freq_write(struct file *filp, const char __user *ubuf, size_t cnt,
dev_priv->rps.min_delay = val / GT_FREQUENCY_MULTIPLIER;

gen6_set_rps(dev, val / GT_FREQUENCY_MULTIPLIER);
mutex_unlock(&dev->struct_mutex);
mutex_unlock(&dev_priv->rps.hw_lock);

return cnt;
}
Expand Down
2 changes: 2 additions & 0 deletions drivers/gpu/drm/i915/i915_dma.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1625,6 +1625,8 @@ int i915_driver_load(struct drm_device *dev, unsigned long flags)
spin_lock_init(&dev_priv->rps.lock);
spin_lock_init(&dev_priv->dpio_lock);

mutex_init(&dev_priv->rps.hw_lock);

if (IS_IVYBRIDGE(dev) || IS_HASWELL(dev))
dev_priv->num_pipe = 3;
else if (IS_MOBILE(dev) || !IS_GEN2(dev))
Expand Down
6 changes: 6 additions & 0 deletions drivers/gpu/drm/i915/i915_drv.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -564,6 +564,12 @@ struct intel_gen6_power_mgmt {
u8 max_delay;

struct delayed_work delayed_resume_work;

/*
* Protects RPS/RC6 register access and PCU communication.
* Must be taken after struct_mutex if nested.
*/
struct mutex hw_lock;
};

struct intel_ilk_power_mgmt {
Expand Down
4 changes: 2 additions & 2 deletions drivers/gpu/drm/i915/i915_irq.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -378,7 +378,7 @@ static void gen6_pm_rps_work(struct work_struct *work)
if ((pm_iir & GEN6_PM_DEFERRED_EVENTS) == 0)
return;

mutex_lock(&dev_priv->dev->struct_mutex);
mutex_lock(&dev_priv->rps.hw_lock);

if (pm_iir & GEN6_PM_RP_UP_THRESHOLD)
new_delay = dev_priv->rps.cur_delay + 1;
Expand All @@ -393,7 +393,7 @@ static void gen6_pm_rps_work(struct work_struct *work)
gen6_set_rps(dev_priv->dev, new_delay);
}

mutex_unlock(&dev_priv->dev->struct_mutex);
mutex_unlock(&dev_priv->rps.hw_lock);
}


Expand Down
37 changes: 12 additions & 25 deletions drivers/gpu/drm/i915/i915_sysfs.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -211,12 +211,9 @@ static ssize_t gt_cur_freq_mhz_show(struct device *kdev,
struct drm_i915_private *dev_priv = dev->dev_private;
int ret;

ret = i915_mutex_lock_interruptible(dev);
if (ret)
return ret;

mutex_lock(&dev_priv->rps.hw_lock);
ret = dev_priv->rps.cur_delay * GT_FREQUENCY_MULTIPLIER;
mutex_unlock(&dev->struct_mutex);
mutex_unlock(&dev_priv->rps.hw_lock);

return snprintf(buf, PAGE_SIZE, "%d", ret);
}
Expand All @@ -228,12 +225,9 @@ static ssize_t gt_max_freq_mhz_show(struct device *kdev, struct device_attribute
struct drm_i915_private *dev_priv = dev->dev_private;
int ret;

ret = i915_mutex_lock_interruptible(dev);
if (ret)
return ret;

mutex_lock(&dev_priv->rps.hw_lock);
ret = dev_priv->rps.max_delay * GT_FREQUENCY_MULTIPLIER;
mutex_unlock(&dev->struct_mutex);
mutex_unlock(&dev_priv->rps.hw_lock);

return snprintf(buf, PAGE_SIZE, "%d", ret);
}
Expand All @@ -254,16 +248,14 @@ static ssize_t gt_max_freq_mhz_store(struct device *kdev,

val /= GT_FREQUENCY_MULTIPLIER;

ret = mutex_lock_interruptible(&dev->struct_mutex);
if (ret)
return ret;
mutex_lock(&dev_priv->rps.hw_lock);

rp_state_cap = I915_READ(GEN6_RP_STATE_CAP);
hw_max = (rp_state_cap & 0xff);
hw_min = ((rp_state_cap & 0xff0000) >> 16);

if (val < hw_min || val > hw_max || val < dev_priv->rps.min_delay) {
mutex_unlock(&dev->struct_mutex);
mutex_unlock(&dev_priv->rps.hw_lock);
return -EINVAL;
}

Expand All @@ -272,7 +264,7 @@ static ssize_t gt_max_freq_mhz_store(struct device *kdev,

dev_priv->rps.max_delay = val;

mutex_unlock(&dev->struct_mutex);
mutex_unlock(&dev_priv->rps.hw_lock);

return count;
}
Expand All @@ -284,12 +276,9 @@ static ssize_t gt_min_freq_mhz_show(struct device *kdev, struct device_attribute
struct drm_i915_private *dev_priv = dev->dev_private;
int ret;

ret = i915_mutex_lock_interruptible(dev);
if (ret)
return ret;

mutex_lock(&dev_priv->rps.hw_lock);
ret = dev_priv->rps.min_delay * GT_FREQUENCY_MULTIPLIER;
mutex_unlock(&dev->struct_mutex);
mutex_unlock(&dev_priv->rps.hw_lock);

return snprintf(buf, PAGE_SIZE, "%d", ret);
}
Expand All @@ -310,16 +299,14 @@ static ssize_t gt_min_freq_mhz_store(struct device *kdev,

val /= GT_FREQUENCY_MULTIPLIER;

ret = mutex_lock_interruptible(&dev->struct_mutex);
if (ret)
return ret;
mutex_lock(&dev_priv->rps.hw_lock);

rp_state_cap = I915_READ(GEN6_RP_STATE_CAP);
hw_max = (rp_state_cap & 0xff);
hw_min = ((rp_state_cap & 0xff0000) >> 16);

if (val < hw_min || val > hw_max || val > dev_priv->rps.max_delay) {
mutex_unlock(&dev->struct_mutex);
mutex_unlock(&dev_priv->rps.hw_lock);
return -EINVAL;
}

Expand All @@ -328,7 +315,7 @@ static ssize_t gt_min_freq_mhz_store(struct device *kdev,

dev_priv->rps.min_delay = val;

mutex_unlock(&dev->struct_mutex);
mutex_unlock(&dev_priv->rps.hw_lock);

return count;

Expand Down
16 changes: 9 additions & 7 deletions drivers/gpu/drm/i915/intel_pm.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -2323,7 +2323,7 @@ void gen6_set_rps(struct drm_device *dev, u8 val)
struct drm_i915_private *dev_priv = dev->dev_private;
u32 limits = gen6_rps_limits(dev_priv, &val);

WARN_ON(!mutex_is_locked(&dev->struct_mutex));
WARN_ON(!mutex_is_locked(&dev_priv->rps.hw_lock));
WARN_ON(val > dev_priv->rps.max_delay);
WARN_ON(val < dev_priv->rps.min_delay);

Expand Down Expand Up @@ -2409,7 +2409,7 @@ static void gen6_enable_rps(struct drm_device *dev)
int rc6_mode;
int i, ret;

WARN_ON(!mutex_is_locked(&dev->struct_mutex));
WARN_ON(!mutex_is_locked(&dev_priv->rps.hw_lock));

/* Here begins a magic sequence of register writes to enable
* auto-downclocking.
Expand Down Expand Up @@ -2550,7 +2550,7 @@ static void gen6_update_ring_freq(struct drm_device *dev)
int gpu_freq, ia_freq, max_ia_freq;
int scaling_factor = 180;

WARN_ON(!mutex_is_locked(&dev->struct_mutex));
WARN_ON(!mutex_is_locked(&dev_priv->rps.hw_lock));

max_ia_freq = cpufreq_quick_get_max(0);
/*
Expand Down Expand Up @@ -3311,7 +3311,9 @@ void intel_disable_gt_powersave(struct drm_device *dev)
ironlake_disable_rc6(dev);
} else if (INTEL_INFO(dev)->gen >= 6 && !IS_VALLEYVIEW(dev)) {
cancel_delayed_work_sync(&dev_priv->rps.delayed_resume_work);
mutex_lock(&dev_priv->rps.hw_lock);
gen6_disable_rps(dev);
mutex_unlock(&dev_priv->rps.hw_lock);
}
}

Expand All @@ -3322,10 +3324,10 @@ static void intel_gen6_powersave_work(struct work_struct *work)
rps.delayed_resume_work.work);
struct drm_device *dev = dev_priv->dev;

mutex_lock(&dev->struct_mutex);
mutex_lock(&dev_priv->rps.hw_lock);
gen6_enable_rps(dev);
gen6_update_ring_freq(dev);
mutex_unlock(&dev->struct_mutex);
mutex_unlock(&dev_priv->rps.hw_lock);
}

void intel_enable_gt_powersave(struct drm_device *dev)
Expand Down Expand Up @@ -4245,7 +4247,7 @@ void intel_gt_init(struct drm_device *dev)

int sandybridge_pcode_read(struct drm_i915_private *dev_priv, u8 mbox, u32 *val)
{
WARN_ON(!mutex_is_locked(&dev_priv->dev->struct_mutex));
WARN_ON(!mutex_is_locked(&dev_priv->rps.hw_lock));

if (I915_READ(GEN6_PCODE_MAILBOX) & GEN6_PCODE_READY) {
DRM_DEBUG_DRIVER("warning: pcode (read) mailbox access failed\n");
Expand All @@ -4269,7 +4271,7 @@ int sandybridge_pcode_read(struct drm_i915_private *dev_priv, u8 mbox, u32 *val)

int sandybridge_pcode_write(struct drm_i915_private *dev_priv, u8 mbox, u32 val)
{
WARN_ON(!mutex_is_locked(&dev_priv->dev->struct_mutex));
WARN_ON(!mutex_is_locked(&dev_priv->rps.hw_lock));

if (I915_READ(GEN6_PCODE_MAILBOX) & GEN6_PCODE_READY) {
DRM_DEBUG_DRIVER("warning: pcode (write) mailbox access failed\n");
Expand Down

0 comments on commit 4fc688c

Please sign in to comment.