drm/i915: Use RPM as the barrier for controlling user mmap access
We can remove the false coupling between RPM and struct mutex by the
observation that we can use the RPM wakeref as the barrier around user
mmap access. That is as we tear down the user's PTE atomically from
within rpm suspend and then to fault in new PTE requires the rpm
wakeref, means that no user access is possible through those PTE without
RPM being awake. Having made that observation, we can then remove the
presumption of having to take rpm outside of struct_mutex and so allow
fine grained acquisition of a wakeref around hw access rather than
having to remember to acquire the wakeref early on.
v2: Rejig placement of the new intel_runtime_pm_get() to be as tight
as possible around the GTT pread/pwrite.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Daniel Vetter <daniel@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161024124218.18252-2-chris@chris-wilson.co.uk
diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index 2d9617a..f85e6fb 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -743,17 +743,32 @@
I915_READ(VLV_IIR_RW));
seq_printf(m, "Display IMR:\t%08x\n",
I915_READ(VLV_IMR));
- for_each_pipe(dev_priv, pipe)
+ for_each_pipe(dev_priv, pipe) {
+ enum intel_display_power_domain power_domain;
+
+ power_domain = POWER_DOMAIN_PIPE(pipe);
+ if (!intel_display_power_get_if_enabled(dev_priv,
+ power_domain)) {
+ seq_printf(m, "Pipe %c power disabled\n",
+ pipe_name(pipe));
+ continue;
+ }
+
seq_printf(m, "Pipe %c stat:\t%08x\n",
pipe_name(pipe),
I915_READ(PIPESTAT(pipe)));
+ intel_display_power_put(dev_priv, power_domain);
+ }
+
+ intel_display_power_get(dev_priv, POWER_DOMAIN_INIT);
seq_printf(m, "Port hotplug:\t%08x\n",
I915_READ(PORT_HOTPLUG_EN));
seq_printf(m, "DPFLIPSTAT:\t%08x\n",
I915_READ(VLV_DPFLIPSTAT));
seq_printf(m, "DPINVGTT:\t%08x\n",
I915_READ(DPINVGTT));
+ intel_display_power_put(dev_priv, POWER_DOMAIN_INIT);
for (i = 0; i < 4; i++) {
seq_printf(m, "GT Interrupt IMR %d:\t%08x\n",
@@ -1396,14 +1411,9 @@
static int ironlake_drpc_info(struct seq_file *m)
{
struct drm_i915_private *dev_priv = node_to_i915(m->private);
- struct drm_device *dev = &dev_priv->drm;
u32 rgvmodectl, rstdbyctl;
u16 crstandvid;
- int ret;
- ret = mutex_lock_interruptible(&dev->struct_mutex);
- if (ret)
- return ret;
intel_runtime_pm_get(dev_priv);
rgvmodectl = I915_READ(MEMMODECTL);
@@ -1411,7 +1421,6 @@
crstandvid = I915_READ16(CRSTANDVID);
intel_runtime_pm_put(dev_priv);
- mutex_unlock(&dev->struct_mutex);
seq_printf(m, "HD boost: %s\n", yesno(rgvmodectl & MEMMODE_BOOST_EN));
seq_printf(m, "Boost freq: %d\n",
@@ -1757,6 +1766,7 @@
bool sr_enabled = false;
intel_runtime_pm_get(dev_priv);
+ intel_display_power_get(dev_priv, POWER_DOMAIN_INIT);
if (HAS_PCH_SPLIT(dev_priv))
sr_enabled = I915_READ(WM1_LP_ILK) & WM1_LP_SR_EN;
@@ -1770,6 +1780,7 @@
else if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv))
sr_enabled = I915_READ(FW_BLC_SELF_VLV) & FW_CSPWRDWNEN;
+ intel_display_power_put(dev_priv, POWER_DOMAIN_INIT);
intel_runtime_pm_put(dev_priv);
seq_printf(m, "self-refresh: %s\n",
@@ -2091,12 +2102,7 @@
static int i915_swizzle_info(struct seq_file *m, void *data)
{
struct drm_i915_private *dev_priv = node_to_i915(m->private);
- struct drm_device *dev = &dev_priv->drm;
- int ret;
- ret = mutex_lock_interruptible(&dev->struct_mutex);
- if (ret)
- return ret;
intel_runtime_pm_get(dev_priv);
seq_printf(m, "bit6 swizzle for X-tiling = %s\n",
@@ -2136,7 +2142,6 @@
seq_puts(m, "L-shaped memory detected\n");
intel_runtime_pm_put(dev_priv);
- mutex_unlock(&dev->struct_mutex);
return 0;
}
@@ -2542,11 +2547,22 @@
enabled = I915_READ(EDP_PSR_CTL) & EDP_PSR_ENABLE;
else {
for_each_pipe(dev_priv, pipe) {
+ enum transcoder cpu_transcoder =
+ intel_pipe_to_cpu_transcoder(dev_priv, pipe);
+ enum intel_display_power_domain power_domain;
+
+ power_domain = POWER_DOMAIN_TRANSCODER(cpu_transcoder);
+ if (!intel_display_power_get_if_enabled(dev_priv,
+ power_domain))
+ continue;
+
stat[pipe] = I915_READ(VLV_PSRSTAT(pipe)) &
VLV_EDP_PSR_CURR_STATE_MASK;
if ((stat[pipe] == VLV_EDP_PSR_ACTIVE_NORFB_UP) ||
(stat[pipe] == VLV_EDP_PSR_ACTIVE_SF_UPDATE))
enabled = true;
+
+ intel_display_power_put(dev_priv, power_domain);
}
}
@@ -3094,6 +3110,8 @@
struct intel_engine_cs *engine;
enum intel_engine_id id;
+ intel_runtime_pm_get(dev_priv);
+
for_each_engine(engine, dev_priv, id) {
struct intel_breadcrumbs *b = &engine->breadcrumbs;
struct drm_i915_gem_request *rq;
@@ -3213,6 +3231,8 @@
seq_puts(m, "\n");
}
+ intel_runtime_pm_put(dev_priv);
+
return 0;
}
@@ -4799,13 +4819,9 @@
if (i915_reset_in_progress(&dev_priv->gpu_error))
return -EAGAIN;
- intel_runtime_pm_get(dev_priv);
-
i915_handle_error(dev_priv, val,
"Manually setting wedged to %llu", val);
- intel_runtime_pm_put(dev_priv);
-
return 0;
}
@@ -5040,22 +5056,16 @@
i915_cache_sharing_get(void *data, u64 *val)
{
struct drm_i915_private *dev_priv = data;
- struct drm_device *dev = &dev_priv->drm;
u32 snpcr;
- int ret;
if (!(IS_GEN6(dev_priv) || IS_GEN7(dev_priv)))
return -ENODEV;
- ret = mutex_lock_interruptible(&dev->struct_mutex);
- if (ret)
- return ret;
intel_runtime_pm_get(dev_priv);
snpcr = I915_READ(GEN6_MBCUNIT_SNPCR);
intel_runtime_pm_put(dev_priv);
- mutex_unlock(&dev->struct_mutex);
*val = (snpcr & GEN6_MBC_SNPCR_MASK) >> GEN6_MBC_SNPCR_SHIFT;