[Intel-gfx] [PATCH] drm/i915: fix up ilk drps/ips locking
Daniel Vetter
daniel.vetter at ffwll.ch
Thu Aug 9 16:46:01 CEST 2012
We change the drps/ips sw/hw state from different callers: Our own irq
handler, the external intel-ips module and from process context. Most
of these callers don't take any lock at all.
Protect everything by making the mchdev_lock irqsave and grabbing it in
all relevant callsites. Note that we have to convert a few sleeps in the
drps enable/disable code to delays, but alas, I'm not volunteering to
restructure the code around a few work items.
For paranoia add a spin_locked assert to ironlake_set_drps, too.
v2: Move one access inside the lock protection. Caught by the
dev_priv->ips mass-rename ...
v3: Resolve rebase conflict.
Signed-off-by: Daniel Vetter <daniel.vetter at ffwll.ch>
---
drivers/gpu/drm/i915/i915_irq.c | 12 +++++-
drivers/gpu/drm/i915/intel_pm.c | 83 ++++++++++++++++++++++-----------------
2 files changed, 58 insertions(+), 37 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index 3e203da..d15ea50 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -296,14 +296,22 @@ static void i915_hotplug_work_func(struct work_struct *work)
drm_helper_hpd_irq_event(dev);
}
+/* defined intel_pm.c */
+extern spinlock_t mchdev_lock;
+
static void ironlake_handle_rps_change(struct drm_device *dev)
{
drm_i915_private_t *dev_priv = dev->dev_private;
u32 busy_up, busy_down, max_avg, min_avg;
- u8 new_delay = dev_priv->cur_delay;
+ u8 new_delay;
+ unsigned long flags;
+
+ spin_lock_irqsave(&mchdev_lock, flags);
I915_WRITE16(MEMINTRSTS, I915_READ(MEMINTRSTS));
+ new_delay = dev_priv->cur_delay;
+
I915_WRITE16(MEMINTRSTS, MEMINT_EVAL_CHG);
busy_up = I915_READ(RCPREVBSYTUPAVG);
busy_down = I915_READ(RCPREVBSYTDNAVG);
@@ -326,6 +334,8 @@ static void ironlake_handle_rps_change(struct drm_device *dev)
if (ironlake_set_drps(dev, new_delay))
dev_priv->cur_delay = new_delay;
+ spin_unlock_irqrestore(&mchdev_lock, flags);
+
return;
}
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index 212b28e..6d68a05 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -2160,11 +2160,28 @@ err_unref:
return NULL;
}
+/**
+ * Lock protecting IPS related data structures
+ * - i915_mch_dev
+ * - dev_priv->max_delay
+ * - dev_priv->min_delay
+ * - dev_priv->fmax
+ * - dev_priv->gpu_busy
+ * - dev_priv->gfx_power
+ */
+DEFINE_SPINLOCK(mchdev_lock);
+
+/* Global for IPS driver to get at the current i915 device. Protected by
+ * mchdev_lock. */
+static struct drm_i915_private *i915_mch_dev;
+
bool ironlake_set_drps(struct drm_device *dev, u8 val)
{
struct drm_i915_private *dev_priv = dev->dev_private;
u16 rgvswctl;
+ assert_spin_locked(&mchdev_lock);
+
rgvswctl = I915_READ16(MEMSWCTL);
if (rgvswctl & MEMCTL_CMD_STS) {
DRM_DEBUG("gpu busy, RCS change rejected\n");
@@ -2188,6 +2205,8 @@ static void ironlake_enable_drps(struct drm_device *dev)
u32 rgvmodectl = I915_READ(MEMMODECTL);
u8 fmax, fmin, fstart, vstart;
+ spin_lock_irq(&mchdev_lock);
+
/* Enable temp reporting */
I915_WRITE16(PMMISC, I915_READ(PMMISC) | MCPPCE_EN);
I915_WRITE16(TSC1, I915_READ(TSC1) | TSE);
@@ -2233,9 +2252,9 @@ static void ironlake_enable_drps(struct drm_device *dev)
rgvmodectl |= MEMMODE_SWMODE_EN;
I915_WRITE(MEMMODECTL, rgvmodectl);
- if (wait_for((I915_READ(MEMSWCTL) & MEMCTL_CMD_STS) == 0, 10))
+ if (wait_for_atomic((I915_READ(MEMSWCTL) & MEMCTL_CMD_STS) == 0, 10))
DRM_ERROR("stuck trying to change perf mode\n");
- msleep(1);
+ mdelay(1);
ironlake_set_drps(dev, fstart);
@@ -2244,12 +2263,18 @@ static void ironlake_enable_drps(struct drm_device *dev)
dev_priv->last_time1 = jiffies_to_msecs(jiffies);
dev_priv->last_count2 = I915_READ(0x112f4);
getrawmonotonic(&dev_priv->last_time2);
+
+ spin_unlock_irq(&mchdev_lock);
}
static void ironlake_disable_drps(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = dev->dev_private;
- u16 rgvswctl = I915_READ16(MEMSWCTL);
+ u16 rgvswctl;
+
+ spin_lock_irq(&mchdev_lock);
+
+ rgvswctl = I915_READ16(MEMSWCTL);
/* Ack interrupts, disable EFC interrupt */
I915_WRITE(MEMINTREN, I915_READ(MEMINTREN) & ~MEMINT_EVAL_CHG_EN);
@@ -2260,11 +2285,12 @@ static void ironlake_disable_drps(struct drm_device *dev)
/* Go back to the starting frequency */
ironlake_set_drps(dev, dev_priv->fstart);
- msleep(1);
+ mdelay(1);
rgvswctl |= MEMCTL_CMD_STS;
I915_WRITE(MEMSWCTL, rgvswctl);
- msleep(1);
+ mdelay(1);
+ spin_unlock_irq(&mchdev_lock);
}
/* There's a funny hw issue where the hw returns all 0 when reading from
@@ -2713,21 +2739,6 @@ static const struct cparams {
{ 0, 800, 231, 23784 },
};
-/**
- * Lock protecting IPS related data structures
- * - i915_mch_dev
- * - dev_priv->max_delay
- * - dev_priv->min_delay
- * - dev_priv->fmax
- * - dev_priv->gpu_busy
- * - dev_priv->gfx_power
- */
-static DEFINE_SPINLOCK(mchdev_lock);
-
-/* Global for IPS driver to get at the current i915 device. Protected by
- * mchdev_lock. */
-static struct drm_i915_private *i915_mch_dev;
-
unsigned long i915_chipset_val(struct drm_i915_private *dev_priv)
{
u64 total_count, diff, ret;
@@ -2978,11 +2989,11 @@ void i915_update_gfx_val(struct drm_i915_private *dev_priv)
if (dev_priv->info->gen != 5)
return;
- spin_lock(&mchdev_lock);
+ spin_lock_irq(&mchdev_lock);
__i915_update_gfx_val(dev_priv);
- spin_unlock(&mchdev_lock);
+ spin_unlock_irq(&mchdev_lock);
}
unsigned long i915_gfx_val(struct drm_i915_private *dev_priv)
@@ -3033,7 +3044,7 @@ unsigned long i915_read_mch_val(void)
struct drm_i915_private *dev_priv;
unsigned long chipset_val, graphics_val, ret = 0;
- spin_lock(&mchdev_lock);
+ spin_lock_irq(&mchdev_lock);
if (!i915_mch_dev)
goto out_unlock;
dev_priv = i915_mch_dev;
@@ -3044,7 +3055,7 @@ unsigned long i915_read_mch_val(void)
ret = chipset_val + graphics_val;
out_unlock:
- spin_unlock(&mchdev_lock);
+ spin_unlock_irq(&mchdev_lock);
return ret;
}
@@ -3060,7 +3071,7 @@ bool i915_gpu_raise(void)
struct drm_i915_private *dev_priv;
bool ret = true;
- spin_lock(&mchdev_lock);
+ spin_lock_irq(&mchdev_lock);
if (!i915_mch_dev) {
ret = false;
goto out_unlock;
@@ -3071,7 +3082,7 @@ bool i915_gpu_raise(void)
dev_priv->max_delay--;
out_unlock:
- spin_unlock(&mchdev_lock);
+ spin_unlock_irq(&mchdev_lock);
return ret;
}
@@ -3088,7 +3099,7 @@ bool i915_gpu_lower(void)
struct drm_i915_private *dev_priv;
bool ret = true;
- spin_lock(&mchdev_lock);
+ spin_lock_irq(&mchdev_lock);
if (!i915_mch_dev) {
ret = false;
goto out_unlock;
@@ -3099,7 +3110,7 @@ bool i915_gpu_lower(void)
dev_priv->max_delay++;
out_unlock:
- spin_unlock(&mchdev_lock);
+ spin_unlock_irq(&mchdev_lock);
return ret;
}
@@ -3117,7 +3128,7 @@ bool i915_gpu_busy(void)
bool ret = false;
int i;
- spin_lock(&mchdev_lock);
+ spin_lock_irq(&mchdev_lock);
if (!i915_mch_dev)
goto out_unlock;
dev_priv = i915_mch_dev;
@@ -3126,7 +3137,7 @@ bool i915_gpu_busy(void)
ret |= !list_empty(&ring->request_list);
out_unlock:
- spin_unlock(&mchdev_lock);
+ spin_unlock_irq(&mchdev_lock);
return ret;
}
@@ -3143,7 +3154,7 @@ bool i915_gpu_turbo_disable(void)
struct drm_i915_private *dev_priv;
bool ret = true;
- spin_lock(&mchdev_lock);
+ spin_lock_irq(&mchdev_lock);
if (!i915_mch_dev) {
ret = false;
goto out_unlock;
@@ -3156,7 +3167,7 @@ bool i915_gpu_turbo_disable(void)
ret = false;
out_unlock:
- spin_unlock(&mchdev_lock);
+ spin_unlock_irq(&mchdev_lock);
return ret;
}
@@ -3186,18 +3197,18 @@ void intel_gpu_ips_init(struct drm_i915_private *dev_priv)
{
/* We only register the i915 ips part with intel-ips once everything is
* set up, to avoid intel-ips sneaking in and reading bogus values. */
- spin_lock(&mchdev_lock);
+ spin_lock_irq(&mchdev_lock);
i915_mch_dev = dev_priv;
- spin_unlock(&mchdev_lock);
+ spin_unlock_irq(&mchdev_lock);
ips_ping_for_i915_load();
}
void intel_gpu_ips_teardown(void)
{
- spin_lock(&mchdev_lock);
+ spin_lock_irq(&mchdev_lock);
i915_mch_dev = NULL;
- spin_unlock(&mchdev_lock);
+ spin_unlock_irq(&mchdev_lock);
}
static void intel_init_emon(struct drm_device *dev)
{
--
1.7.10.4
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