[Intel-gfx] [PATCH 13/18] drm/i915: Use request_firmware and our own async work

[Animesh Manna]

From: Daniel Vetter <daniel.vetter at intel.com>

Two benefits:
- We can use FW_LOADER_USERSPACE_FALLBACK.
- We can use flush_work to synchronize with the oustanding worker,
  which is a notch more obvious what it does than having a special
  completion.

The next patch will properly synchronize against the async loader in
the resume and unload code.

Cc: Damien Lespiau <damien.lespiau at intel.com>
Cc: Imre Deak <imre.deak at intel.com>
Cc: Sunil Kamath <sunil.kamath at intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter at intel.com>
Signed-off-by: Animesh Manna <animesh.manna at intel.com>
---
 drivers/gpu/drm/i915/i915_drv.h  |  1 +
 drivers/gpu/drm/i915/intel_csr.c | 22 +++++++++++-----------
 2 files changed, 12 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 1117300..b45f6b4 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -735,6 +735,7 @@ struct intel_uncore {
 	for_each_fw_domain_mask(domain__, FORCEWAKE_ALL, dev_priv__, i__)
 
 struct intel_csr {
+	struct work_struct work;
 	const char *fw_path;
 	uint32_t *dmc_payload;
 	uint32_t dmc_fw_size;
diff --git a/drivers/gpu/drm/i915/intel_csr.c b/drivers/gpu/drm/i915/intel_csr.c
index f42449b..36386324 100644
--- a/drivers/gpu/drm/i915/intel_csr.c
+++ b/drivers/gpu/drm/i915/intel_csr.c
@@ -341,10 +341,16 @@ static uint32_t *parse_csr_fw(struct drm_i915_private *dev_priv,
 	return dmc_payload;
 }
 
-static void finish_csr_load(const struct firmware *fw, void *context)
+static void csr_load_work_fn(struct work_struct *work)
 {
-	struct drm_i915_private *dev_priv = context;
+	struct drm_i915_private *dev_priv;
+	const struct firmware *fw;
+	int ret;
+
+	dev_priv = container_of(work, typeof(*dev_priv), csr.work);
 
+	ret = request_firmware(&fw, dev_priv->csr.fw_path,
+			       &dev_priv->dev->pdev->dev);
 	if (!fw)
 		goto out;
 
@@ -380,7 +386,8 @@ out:
 void intel_csr_ucode_init(struct drm_i915_private *dev_priv)
 {
 	struct intel_csr *csr = &dev_priv->csr;
-	int ret;
+
+	INIT_WORK(&dev_priv->csr.work, csr_load_work_fn);
 
 	if (!HAS_CSR(dev_priv))
 		return;
@@ -390,19 +397,12 @@ void intel_csr_ucode_init(struct drm_i915_private *dev_priv)
 	else if (IS_BROXTON(dev_priv))
 		csr->fw_path = I915_CSR_BXT;
 
-	DRM_DEBUG_KMS("Loading %s\n", csr->fw_path);
-
 	/*
 	 * Obtain a runtime pm reference, until CSR is loaded,
 	 * to avoid entering runtime-suspend.
 	 */
 	intel_runtime_pm_get(dev_priv);
-
-	/* CSR supported for platform, load firmware */
-	ret = request_firmware_nowait(THIS_MODULE, true, csr->fw_path,
-				      &dev_priv->dev->pdev->dev,
-				      GFP_KERNEL, dev_priv,
-				      finish_csr_load);
+	schedule_work(&dev_priv->csr.work);
 }
 
 /**
-- 
2.0.2