drm/gma500: Never wait for blits

Blits cannot happen anymore since we removed the 2d accel code. Stop
checking for a busy blitter and remove the remaining blitter code.
Signed-off-by: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20210201132617.1233-6-patrik.r.jakobsson@gmail.com

drivers/gpu/drm/gma500/Makefile

@@ -5,7 +5,6 @@
 
 gma500_gfx-y += \
 	  backlight.o \
-	  blitter.o \
 	  cdv_device.o \
 	  cdv_intel_crt.o \
 	  cdv_intel_display.o \

drivers/gpu/drm/gma500/blitter.c

-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * Copyright (c) 2014, Patrik Jakobsson
- * All Rights Reserved.
- *
- * Authors: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
- */
-
-#include "psb_drv.h"
-
-#include "blitter.h"
-#include "psb_reg.h"
-
-/* Wait for the blitter to be completely idle */
-int gma_blt_wait_idle(struct drm_psb_private *dev_priv)
-{
-	unsigned long stop = jiffies + HZ;
-	int busy = 1;
-
-	/* NOP for Cedarview */
-	if (IS_CDV(dev_priv->dev))
-		return 0;
-
-	/* First do a quick check */
-	if ((PSB_RSGX32(PSB_CR_2D_SOCIF) == _PSB_C2_SOCIF_EMPTY) &&
-	    ((PSB_RSGX32(PSB_CR_2D_BLIT_STATUS) & _PSB_C2B_STATUS_BUSY) == 0))
-		return 0;
-
-	do {
-		busy = (PSB_RSGX32(PSB_CR_2D_SOCIF) != _PSB_C2_SOCIF_EMPTY);
-	} while (busy && !time_after_eq(jiffies, stop));
-
-	if (busy)
-		return -EBUSY;
-
-	do {
-		busy = ((PSB_RSGX32(PSB_CR_2D_BLIT_STATUS) &
-			_PSB_C2B_STATUS_BUSY) != 0);
-	} while (busy && !time_after_eq(jiffies, stop));
-
-	/* If still busy, we probably have a hang */
-	return (busy) ? -EBUSY : 0;
-}

drivers/gpu/drm/gma500/blitter.h

-/* SPDX-License-Identifier: GPL-2.0-only */
-/*
- * Copyright (c) 2014, Patrik Jakobsson
- * All Rights Reserved.
- *
- * Authors: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
- */
-
-#ifndef __BLITTER_H
-#define __BLITTER_H
-
-struct drm_psb_private;
-
-extern int gma_blt_wait_idle(struct drm_psb_private *dev_priv);
-
-#endif

drivers/gpu/drm/gma500/gtt.c

@@ -11,7 +11,6 @@
 
 #include <asm/set_memory.h>
 
-#include "blitter.h"
 #include "psb_drv.h"
 
 
@@ -229,18 +228,9 @@ void psb_gtt_unpin(struct gtt_range *gt)
 	struct drm_device *dev = gt->gem.dev;
 	struct drm_psb_private *dev_priv = dev->dev_private;
 	u32 gpu_base = dev_priv->gtt.gatt_start;
-	int ret;
 
-	/* While holding the gtt_mutex no new blits can be initiated */
 	mutex_lock(&dev_priv->gtt_mutex);
 
-	/* Wait for any possible usage of the memory to be finished */
-	ret = gma_blt_wait_idle(dev_priv);
-	if (ret) {
-		DRM_ERROR("Failed to idle the blitter, unpin failed!");
-		goto out;
-	}
-
 	WARN_ON(!gt->in_gart);
 
 	gt->in_gart--;
@@ -251,7 +241,6 @@ void psb_gtt_unpin(struct gtt_range *gt)
 		psb_gtt_detach_pages(gt);
 	}
 
-out:
 	mutex_unlock(&dev_priv->gtt_mutex);
 }