1// SPDX-License-Identifier: GPL-2.0-only
 2/*
 3 * Copyright (c) 2014, Patrik Jakobsson
 4 * All Rights Reserved.
 5 *
 6 * Authors: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
 7 */
 8
 9#include "psb_drv.h"
10
11#include "blitter.h"
12#include "psb_reg.h"
13
14/* Wait for the blitter to be completely idle */
15int gma_blt_wait_idle(struct drm_psb_private *dev_priv)
16{
17	unsigned long stop = jiffies + HZ;
18	int busy = 1;
19
20	/* NOP for Cedarview */
21	if (IS_CDV(dev_priv->dev))
22		return 0;
23
24	/* First do a quick check */
25	if ((PSB_RSGX32(PSB_CR_2D_SOCIF) == _PSB_C2_SOCIF_EMPTY) &&
26	    ((PSB_RSGX32(PSB_CR_2D_BLIT_STATUS) & _PSB_C2B_STATUS_BUSY) == 0))
27		return 0;
28
29	do {
30		busy = (PSB_RSGX32(PSB_CR_2D_SOCIF) != _PSB_C2_SOCIF_EMPTY);
31	} while (busy && !time_after_eq(jiffies, stop));
32
33	if (busy)
34		return -EBUSY;
35
36	do {
37		busy = ((PSB_RSGX32(PSB_CR_2D_BLIT_STATUS) &
38			_PSB_C2B_STATUS_BUSY) != 0);
39	} while (busy && !time_after_eq(jiffies, stop));
40
41	/* If still busy, we probably have a hang */
42	return (busy) ? -EBUSY : 0;
43}