diff mbox

[DMC_REDESIGN_V2,05/14] drm/i915/gen9: Remove csr.state, csr_lock and related code.

Message ID 1440588497-13954-6-git-send-email-animesh.manna@intel.com (mailing list archive)
State New, archived
Headers show

Commit Message

Manna, Animesh Aug. 26, 2015, 11:28 a.m. UTC 
From: Daniel Vetter <daniel.vetter@intel.com>

This removes two anti-patterns:
- Locking shouldn't be used to synchronize with async work (of any
  form, whether callbacks, workers or other threads). This is what the
  mutex_lock/unlock seems to have been for in intel_csr_load_program.
  Instead ordering should be ensured with the generic
  wait_for_completion()/complete(). Or more specific functions
  provided by the core kernel like e.g.
  flush_work()/cancel_work_sync() in the case of synchronizing with a
  work item.

- Don't invent own completion like the following code did with the
  (already removed) wait_for(csr_load_status_get()) pattern - it's
  really hard to get these right when you want them to be _really_
  correct (and be fast) in all cases. Furthermore it's easier to read
  code using the well-known primitives than new ones using
  non-standard names.

Cc: Damien Lespiau <damien.lespiau@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Sunil Kamath <sunil.kamath@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Signed-off-by: Animesh Manna <animesh.manna@intel.com>
---
 drivers/gpu/drm/i915/i915_dma.c         |  1 -
 drivers/gpu/drm/i915/i915_drv.c         | 13 ++--------
 drivers/gpu/drm/i915/i915_drv.h         | 10 -------
 drivers/gpu/drm/i915/intel_csr.c        | 46 +--------------------------------
 drivers/gpu/drm/i915/intel_drv.h        |  3 ---
 drivers/gpu/drm/i915/intel_runtime_pm.c | 17 ++----------
 6 files changed, 5 insertions(+), 85 deletions(-)

Comments

Imre Deak Oct. 22, 2015, 3:39 p.m. UTC | #1 
On ke, 2015-08-26 at 16:58 +0530, Animesh Manna wrote:
> From: Daniel Vetter <daniel.vetter@intel.com>
> 
> This removes two anti-patterns:
> - Locking shouldn't be used to synchronize with async work (of any
>   form, whether callbacks, workers or other threads). This is what the
>   mutex_lock/unlock seems to have been for in intel_csr_load_program.
>   Instead ordering should be ensured with the generic
>   wait_for_completion()/complete(). Or more specific functions
>   provided by the core kernel like e.g.
>   flush_work()/cancel_work_sync() in the case of synchronizing with a
>   work item.
> 
> - Don't invent own completion like the following code did with the
>   (already removed) wait_for(csr_load_status_get()) pattern - it's
>   really hard to get these right when you want them to be _really_
>   correct (and be fast) in all cases. Furthermore it's easier to read
>   code using the well-known primitives than new ones using
>   non-standard names.
> 
> Cc: Damien Lespiau <damien.lespiau@intel.com>
> Cc: Imre Deak <imre.deak@intel.com>
> Cc: Sunil Kamath <sunil.kamath@intel.com>
> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
> Signed-off-by: Animesh Manna <animesh.manna@intel.com>
> ---
>  drivers/gpu/drm/i915/i915_dma.c         |  1 -
>  drivers/gpu/drm/i915/i915_drv.c         | 13 ++--------
>  drivers/gpu/drm/i915/i915_drv.h         | 10 -------
>  drivers/gpu/drm/i915/intel_csr.c        | 46 +--------------------------------
>  drivers/gpu/drm/i915/intel_drv.h        |  3 ---
>  drivers/gpu/drm/i915/intel_runtime_pm.c | 17 ++----------
>  6 files changed, 5 insertions(+), 85 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
> index 48b9792..aa3cdcf 100644
> --- a/drivers/gpu/drm/i915/i915_dma.c
> +++ b/drivers/gpu/drm/i915/i915_dma.c
> @@ -839,7 +839,6 @@ int i915_driver_load(struct drm_device *dev, unsigned long flags)
>  	spin_lock_init(&dev_priv->mmio_flip_lock);
>  	mutex_init(&dev_priv->sb_lock);
>  	mutex_init(&dev_priv->modeset_restore_lock);
> -	mutex_init(&dev_priv->csr_lock);
>  
>  	intel_pm_setup(dev);
>  
> diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
> index fa66162..1ddf3a9 100644
> --- a/drivers/gpu/drm/i915/i915_drv.c
> +++ b/drivers/gpu/drm/i915/i915_drv.c
> @@ -1013,19 +1013,11 @@ static int i915_pm_resume(struct device *dev)
>  
>  static int skl_suspend_complete(struct drm_i915_private *dev_priv)
>  {
> -	enum csr_state state;
>  	/* Enabling DC6 is not a hard requirement to enter runtime D3 */
>  
>  	skl_uninit_cdclk(dev_priv);
>  
> -	/* TODO: wait for a completion event or
> -	 * similar here instead of busy
> -	 * waiting using wait_for function.
> -	 */
> -	wait_for((state = intel_csr_load_status_get(dev_priv)) !=
> -			FW_UNINITIALIZED, 1000);
> -	if (state == FW_LOADED)
> -		skl_enable_dc6(dev_priv);
> +	skl_enable_dc6(dev_priv);

Here the firmware may not be loaded yet during system suspend. Since
patch 11/14 moves the firmware loading to a work item, we could flush
that work in i915_drm_suspend() and check here if csr->dmc_payload is
set before enabling DC6. (and reorder this patch after patch 11).

>  
>  	return 0;
>  }
> @@ -1073,8 +1065,7 @@ static int skl_resume_prepare(struct drm_i915_private *dev_priv)
>  {
>  	struct drm_device *dev = dev_priv->dev;
>  
> -	if (intel_csr_load_status_get(dev_priv) == FW_LOADED)
> -		skl_disable_dc6(dev_priv);
> +	skl_disable_dc6(dev_priv);

As above we should check here for csr->dmc_payload.

>  	skl_init_cdclk(dev_priv);
>  	intel_csr_load_program(dev);
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index e0f3f05..9f01c72 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -736,12 +736,6 @@ struct intel_uncore {
>  #define for_each_fw_domain(domain__, dev_priv__, i__) \
>  	for_each_fw_domain_mask(domain__, FORCEWAKE_ALL, dev_priv__, i__)
>  
> -enum csr_state {
> -	FW_UNINITIALIZED = 0,
> -	FW_LOADED,
> -	FW_FAILED
> -};
> -
>  struct intel_csr {
>  	const char *fw_path;
>  	uint32_t *dmc_payload;
> @@ -749,7 +743,6 @@ struct intel_csr {
>  	uint32_t mmio_count;
>  	uint32_t mmioaddr[8];
>  	uint32_t mmiodata[8];
> -	enum csr_state state;
>  };
>  
>  #define DEV_INFO_FOR_EACH_FLAG(func, sep) \
> @@ -1714,9 +1707,6 @@ struct drm_i915_private {
>  
>  	struct intel_csr csr;
>  
> -	/* Display CSR-related protection */
> -	struct mutex csr_lock;
> -
>  	struct intel_gmbus gmbus[GMBUS_NUM_PINS];
>  
>  	/** gmbus_mutex protects against concurrent usage of the single hw gmbus
> diff --git a/drivers/gpu/drm/i915/intel_csr.c b/drivers/gpu/drm/i915/intel_csr.c
> index 9153764..ee2079b 100644
> --- a/drivers/gpu/drm/i915/intel_csr.c
> +++ b/drivers/gpu/drm/i915/intel_csr.c
> @@ -184,40 +184,6 @@ static char intel_get_substepping(struct drm_device *dev)
>  }
>  
>  /**
> - * intel_csr_load_status_get() - to get firmware loading status.
> - * @dev_priv: i915 device.
> - *
> - * This function helps to get the firmware loading status.
> - *
> - * Return: Firmware loading status.
> - */
> -enum csr_state intel_csr_load_status_get(struct drm_i915_private *dev_priv)
> -{
> -	enum csr_state state;
> -
> -	mutex_lock(&dev_priv->csr_lock);
> -	state = dev_priv->csr.state;
> -	mutex_unlock(&dev_priv->csr_lock);
> -
> -	return state;
> -}
> -
> -/**
> - * intel_csr_load_status_set() - help to set firmware loading status.
> - * @dev_priv: i915 device.
> - * @state: enumeration of firmware loading status.
> - *
> - * Set the firmware loading status.
> - */
> -void intel_csr_load_status_set(struct drm_i915_private *dev_priv,
> -			enum csr_state state)
> -{
> -	mutex_lock(&dev_priv->csr_lock);
> -	dev_priv->csr.state = state;
> -	mutex_unlock(&dev_priv->csr_lock);
> -}
> -
> -/**
>   * intel_csr_load_program() - write the firmware from memory to register.
>   * @dev: drm device.
>   *
> @@ -245,7 +211,6 @@ void intel_csr_load_program(struct drm_device *dev)
>  	if (I915_READ(CSR_PROGRAM_BASE))
>  		return;
>  
> -	mutex_lock(&dev_priv->csr_lock);
>  	fw_size = dev_priv->csr.dmc_fw_size;
>  	for (i = 0; i < fw_size; i++)
>  		I915_WRITE(CSR_PROGRAM_BASE + i * 4,
> @@ -255,9 +220,6 @@ void intel_csr_load_program(struct drm_device *dev)
>  		I915_WRITE(dev_priv->csr.mmioaddr[i],
>  			dev_priv->csr.mmiodata[i]);
>  	}
> -
> -	dev_priv->csr.state = FW_LOADED;
> -	mutex_unlock(&dev_priv->csr_lock);
>  }
>  
>  static void finish_csr_load(const struct firmware *fw, void *context)
> @@ -378,8 +340,6 @@ static void finish_csr_load(const struct firmware *fw, void *context)
>  out:
>  	if (fw_loaded || IS_BROXTON(dev))
>  		intel_display_power_put(dev_priv, POWER_DOMAIN_INIT);
> -	else
> -		intel_csr_load_status_set(dev_priv, FW_FAILED);
>  
>  	release_firmware(fw);
>  }
> @@ -404,7 +364,6 @@ void intel_csr_ucode_init(struct drm_device *dev)
>  		csr->fw_path = I915_CSR_SKL;
>  	else {
>  		DRM_ERROR("Unexpected: no known CSR firmware for platform\n");
> -		intel_csr_load_status_set(dev_priv, FW_FAILED);
>  		return;
>  	}
>  
> @@ -421,10 +380,8 @@ void intel_csr_ucode_init(struct drm_device *dev)
>  				&dev_priv->dev->pdev->dev,
>  				GFP_KERNEL, dev_priv,
>  				finish_csr_load);
> -	if (ret) {
> +	if (ret)
>  		i915_firmware_load_error_print(csr->fw_path, ret);
> -		intel_csr_load_status_set(dev_priv, FW_FAILED);
> -	}
>  }
>  
>  /**
> @@ -441,7 +398,6 @@ void intel_csr_ucode_fini(struct drm_device *dev)
>  	if (!HAS_CSR(dev))
>  		return;
>  
> -	intel_csr_load_status_set(dev_priv, FW_FAILED);
>  	kfree(dev_priv->csr.dmc_payload);
>  }
>  
> diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
> index c178ae8..a5e4b08 100644
> --- a/drivers/gpu/drm/i915/intel_drv.h
> +++ b/drivers/gpu/drm/i915/intel_drv.h
> @@ -1152,9 +1152,6 @@ u32 skl_plane_ctl_rotation(unsigned int rotation);
>  
>  /* intel_csr.c */
>  void intel_csr_ucode_init(struct drm_device *dev);
> -enum csr_state intel_csr_load_status_get(struct drm_i915_private *dev_priv);
> -void intel_csr_load_status_set(struct drm_i915_private *dev_priv,
> -					enum csr_state state);
>  void intel_csr_load_program(struct drm_device *dev);
>  void intel_csr_ucode_fini(struct drm_device *dev);
>  
> diff --git a/drivers/gpu/drm/i915/intel_runtime_pm.c b/drivers/gpu/drm/i915/intel_runtime_pm.c
> index 71832dc..3ffebb7 100644
> --- a/drivers/gpu/drm/i915/intel_runtime_pm.c
> +++ b/drivers/gpu/drm/i915/intel_runtime_pm.c
> @@ -661,8 +661,7 @@ static void skl_set_power_well(struct drm_i915_private *dev_priv,
>  	} else {
>  		if (enable_requested) {
>  			if (IS_SKYLAKE(dev) &&
> -				(power_well->data == SKL_DISP_PW_1) &&
> -				(intel_csr_load_status_get(dev_priv) == FW_LOADED))
> +				(power_well->data == SKL_DISP_PW_1))
>  				DRM_DEBUG_KMS("Not Disabling PW1, dmc will handle\n");
>  			else {
>  				I915_WRITE(HSW_PWR_WELL_DRIVER,	tmp & ~req_mask);
> @@ -671,20 +670,8 @@ static void skl_set_power_well(struct drm_i915_private *dev_priv,
>  			}
>  
>  			if (GEN9_ENABLE_DC5(dev) &&
> -				power_well->data == SKL_DISP_PW_2) {
> -				enum csr_state state;
> -				/* TODO: wait for a completion event or
> -				 * similar here instead of busy
> -				 * waiting using wait_for function.
> -				 */
> -				wait_for((state = intel_csr_load_status_get(dev_priv)) !=
> -						FW_UNINITIALIZED, 1000);
> -				if (state != FW_LOADED)
> -					DRM_ERROR("CSR firmware not ready (%d)\n",
> -							state);
> -				else
> +				power_well->data == SKL_DISP_PW_2)
>  					gen9_enable_dc5(dev_priv);
> -			}
>  		}
>  	}
>
diff mbox

Patch

diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
index 48b9792..aa3cdcf 100644
--- a/drivers/gpu/drm/i915/i915_dma.c
+++ b/drivers/gpu/drm/i915/i915_dma.c
@@ -839,7 +839,6 @@  int i915_driver_load(struct drm_device *dev, unsigned long flags)
 	spin_lock_init(&dev_priv->mmio_flip_lock);
 	mutex_init(&dev_priv->sb_lock);
 	mutex_init(&dev_priv->modeset_restore_lock);
-	mutex_init(&dev_priv->csr_lock);
 
 	intel_pm_setup(dev);
 
diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index fa66162..1ddf3a9 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -1013,19 +1013,11 @@  static int i915_pm_resume(struct device *dev)
 
 static int skl_suspend_complete(struct drm_i915_private *dev_priv)
 {
-	enum csr_state state;
 	/* Enabling DC6 is not a hard requirement to enter runtime D3 */
 
 	skl_uninit_cdclk(dev_priv);
 
-	/* TODO: wait for a completion event or
-	 * similar here instead of busy
-	 * waiting using wait_for function.
-	 */
-	wait_for((state = intel_csr_load_status_get(dev_priv)) !=
-			FW_UNINITIALIZED, 1000);
-	if (state == FW_LOADED)
-		skl_enable_dc6(dev_priv);
+	skl_enable_dc6(dev_priv);
 
 	return 0;
 }
@@ -1073,8 +1065,7 @@  static int skl_resume_prepare(struct drm_i915_private *dev_priv)
 {
 	struct drm_device *dev = dev_priv->dev;
 
-	if (intel_csr_load_status_get(dev_priv) == FW_LOADED)
-		skl_disable_dc6(dev_priv);
+	skl_disable_dc6(dev_priv);
 
 	skl_init_cdclk(dev_priv);
 	intel_csr_load_program(dev);
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index e0f3f05..9f01c72 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -736,12 +736,6 @@  struct intel_uncore {
 #define for_each_fw_domain(domain__, dev_priv__, i__) \
 	for_each_fw_domain_mask(domain__, FORCEWAKE_ALL, dev_priv__, i__)
 
-enum csr_state {
-	FW_UNINITIALIZED = 0,
-	FW_LOADED,
-	FW_FAILED
-};
-
 struct intel_csr {
 	const char *fw_path;
 	uint32_t *dmc_payload;
@@ -749,7 +743,6 @@  struct intel_csr {
 	uint32_t mmio_count;
 	uint32_t mmioaddr[8];
 	uint32_t mmiodata[8];
-	enum csr_state state;
 };
 
 #define DEV_INFO_FOR_EACH_FLAG(func, sep) \
@@ -1714,9 +1707,6 @@  struct drm_i915_private {
 
 	struct intel_csr csr;
 
-	/* Display CSR-related protection */
-	struct mutex csr_lock;
-
 	struct intel_gmbus gmbus[GMBUS_NUM_PINS];
 
 	/** gmbus_mutex protects against concurrent usage of the single hw gmbus
diff --git a/drivers/gpu/drm/i915/intel_csr.c b/drivers/gpu/drm/i915/intel_csr.c
index 9153764..ee2079b 100644
--- a/drivers/gpu/drm/i915/intel_csr.c
+++ b/drivers/gpu/drm/i915/intel_csr.c
@@ -184,40 +184,6 @@  static char intel_get_substepping(struct drm_device *dev)
 }
 
 /**
- * intel_csr_load_status_get() - to get firmware loading status.
- * @dev_priv: i915 device.
- *
- * This function helps to get the firmware loading status.
- *
- * Return: Firmware loading status.
- */
-enum csr_state intel_csr_load_status_get(struct drm_i915_private *dev_priv)
-{
-	enum csr_state state;
-
-	mutex_lock(&dev_priv->csr_lock);
-	state = dev_priv->csr.state;
-	mutex_unlock(&dev_priv->csr_lock);
-
-	return state;
-}
-
-/**
- * intel_csr_load_status_set() - help to set firmware loading status.
- * @dev_priv: i915 device.
- * @state: enumeration of firmware loading status.
- *
- * Set the firmware loading status.
- */
-void intel_csr_load_status_set(struct drm_i915_private *dev_priv,
-			enum csr_state state)
-{
-	mutex_lock(&dev_priv->csr_lock);
-	dev_priv->csr.state = state;
-	mutex_unlock(&dev_priv->csr_lock);
-}
-
-/**
  * intel_csr_load_program() - write the firmware from memory to register.
  * @dev: drm device.
  *
@@ -245,7 +211,6 @@  void intel_csr_load_program(struct drm_device *dev)
 	if (I915_READ(CSR_PROGRAM_BASE))
 		return;
 
-	mutex_lock(&dev_priv->csr_lock);
 	fw_size = dev_priv->csr.dmc_fw_size;
 	for (i = 0; i < fw_size; i++)
 		I915_WRITE(CSR_PROGRAM_BASE + i * 4,
@@ -255,9 +220,6 @@  void intel_csr_load_program(struct drm_device *dev)
 		I915_WRITE(dev_priv->csr.mmioaddr[i],
 			dev_priv->csr.mmiodata[i]);
 	}
-
-	dev_priv->csr.state = FW_LOADED;
-	mutex_unlock(&dev_priv->csr_lock);
 }
 
 static void finish_csr_load(const struct firmware *fw, void *context)
@@ -378,8 +340,6 @@  static void finish_csr_load(const struct firmware *fw, void *context)
 out:
 	if (fw_loaded || IS_BROXTON(dev))
 		intel_display_power_put(dev_priv, POWER_DOMAIN_INIT);
-	else
-		intel_csr_load_status_set(dev_priv, FW_FAILED);
 
 	release_firmware(fw);
 }
@@ -404,7 +364,6 @@  void intel_csr_ucode_init(struct drm_device *dev)
 		csr->fw_path = I915_CSR_SKL;
 	else {
 		DRM_ERROR("Unexpected: no known CSR firmware for platform\n");
-		intel_csr_load_status_set(dev_priv, FW_FAILED);
 		return;
 	}
 
@@ -421,10 +380,8 @@  void intel_csr_ucode_init(struct drm_device *dev)
 				&dev_priv->dev->pdev->dev,
 				GFP_KERNEL, dev_priv,
 				finish_csr_load);
-	if (ret) {
+	if (ret)
 		i915_firmware_load_error_print(csr->fw_path, ret);
-		intel_csr_load_status_set(dev_priv, FW_FAILED);
-	}
 }
 
 /**
@@ -441,7 +398,6 @@  void intel_csr_ucode_fini(struct drm_device *dev)
 	if (!HAS_CSR(dev))
 		return;
 
-	intel_csr_load_status_set(dev_priv, FW_FAILED);
 	kfree(dev_priv->csr.dmc_payload);
 }
 
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index c178ae8..a5e4b08 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -1152,9 +1152,6 @@  u32 skl_plane_ctl_rotation(unsigned int rotation);
 
 /* intel_csr.c */
 void intel_csr_ucode_init(struct drm_device *dev);
-enum csr_state intel_csr_load_status_get(struct drm_i915_private *dev_priv);
-void intel_csr_load_status_set(struct drm_i915_private *dev_priv,
-					enum csr_state state);
 void intel_csr_load_program(struct drm_device *dev);
 void intel_csr_ucode_fini(struct drm_device *dev);
 
diff --git a/drivers/gpu/drm/i915/intel_runtime_pm.c b/drivers/gpu/drm/i915/intel_runtime_pm.c
index 71832dc..3ffebb7 100644
--- a/drivers/gpu/drm/i915/intel_runtime_pm.c
+++ b/drivers/gpu/drm/i915/intel_runtime_pm.c
@@ -661,8 +661,7 @@  static void skl_set_power_well(struct drm_i915_private *dev_priv,
 	} else {
 		if (enable_requested) {
 			if (IS_SKYLAKE(dev) &&
-				(power_well->data == SKL_DISP_PW_1) &&
-				(intel_csr_load_status_get(dev_priv) == FW_LOADED))
+				(power_well->data == SKL_DISP_PW_1))
 				DRM_DEBUG_KMS("Not Disabling PW1, dmc will handle\n");
 			else {
 				I915_WRITE(HSW_PWR_WELL_DRIVER,	tmp & ~req_mask);
@@ -671,20 +670,8 @@  static void skl_set_power_well(struct drm_i915_private *dev_priv,
 			}
 
 			if (GEN9_ENABLE_DC5(dev) &&
-				power_well->data == SKL_DISP_PW_2) {
-				enum csr_state state;
-				/* TODO: wait for a completion event or
-				 * similar here instead of busy
-				 * waiting using wait_for function.
-				 */
-				wait_for((state = intel_csr_load_status_get(dev_priv)) !=
-						FW_UNINITIALIZED, 1000);
-				if (state != FW_LOADED)
-					DRM_ERROR("CSR firmware not ready (%d)\n",
-							state);
-				else
+				power_well->data == SKL_DISP_PW_2)
 					gen9_enable_dc5(dev_priv);
-			}
 		}
 	}