cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

mga_irq.c (4940B)


      1/* mga_irq.c -- IRQ handling for radeon -*- linux-c -*-
      2 */
      3/*
      4 * Copyright (C) The Weather Channel, Inc.  2002.  All Rights Reserved.
      5 *
      6 * The Weather Channel (TM) funded Tungsten Graphics to develop the
      7 * initial release of the Radeon 8500 driver under the XFree86 license.
      8 * This notice must be preserved.
      9 *
     10 * Permission is hereby granted, free of charge, to any person obtaining a
     11 * copy of this software and associated documentation files (the "Software"),
     12 * to deal in the Software without restriction, including without limitation
     13 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
     14 * and/or sell copies of the Software, and to permit persons to whom the
     15 * Software is furnished to do so, subject to the following conditions:
     16 *
     17 * The above copyright notice and this permission notice (including the next
     18 * paragraph) shall be included in all copies or substantial portions of the
     19 * Software.
     20 *
     21 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
     22 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
     23 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
     24 * PRECISION INSIGHT AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
     25 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
     26 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
     27 * DEALINGS IN THE SOFTWARE.
     28 *
     29 * Authors:
     30 *    Keith Whitwell <keith@tungstengraphics.com>
     31 *    Eric Anholt <anholt@FreeBSD.org>
     32 */
     33
     34#include "mga_drv.h"
     35
     36u32 mga_get_vblank_counter(struct drm_device *dev, unsigned int pipe)
     37{
     38	const drm_mga_private_t *const dev_priv =
     39		(drm_mga_private_t *) dev->dev_private;
     40
     41	if (pipe != 0)
     42		return 0;
     43
     44	return atomic_read(&dev_priv->vbl_received);
     45}
     46
     47
     48irqreturn_t mga_driver_irq_handler(int irq, void *arg)
     49{
     50	struct drm_device *dev = (struct drm_device *) arg;
     51	drm_mga_private_t *dev_priv = (drm_mga_private_t *) dev->dev_private;
     52	int status;
     53	int handled = 0;
     54
     55	status = MGA_READ(MGA_STATUS);
     56
     57	/* VBLANK interrupt */
     58	if (status & MGA_VLINEPEN) {
     59		MGA_WRITE(MGA_ICLEAR, MGA_VLINEICLR);
     60		atomic_inc(&dev_priv->vbl_received);
     61		drm_handle_vblank(dev, 0);
     62		handled = 1;
     63	}
     64
     65	/* SOFTRAP interrupt */
     66	if (status & MGA_SOFTRAPEN) {
     67		const u32 prim_start = MGA_READ(MGA_PRIMADDRESS);
     68		const u32 prim_end = MGA_READ(MGA_PRIMEND);
     69
     70
     71		MGA_WRITE(MGA_ICLEAR, MGA_SOFTRAPICLR);
     72
     73		/* In addition to clearing the interrupt-pending bit, we
     74		 * have to write to MGA_PRIMEND to re-start the DMA operation.
     75		 */
     76		if ((prim_start & ~0x03) != (prim_end & ~0x03))
     77			MGA_WRITE(MGA_PRIMEND, prim_end);
     78
     79		atomic_inc(&dev_priv->last_fence_retired);
     80		wake_up(&dev_priv->fence_queue);
     81		handled = 1;
     82	}
     83
     84	if (handled)
     85		return IRQ_HANDLED;
     86	return IRQ_NONE;
     87}
     88
     89int mga_enable_vblank(struct drm_device *dev, unsigned int pipe)
     90{
     91	drm_mga_private_t *dev_priv = (drm_mga_private_t *) dev->dev_private;
     92
     93	if (pipe != 0) {
     94		DRM_ERROR("tried to enable vblank on non-existent crtc %u\n",
     95			  pipe);
     96		return 0;
     97	}
     98
     99	MGA_WRITE(MGA_IEN, MGA_VLINEIEN | MGA_SOFTRAPEN);
    100	return 0;
    101}
    102
    103
    104void mga_disable_vblank(struct drm_device *dev, unsigned int pipe)
    105{
    106	if (pipe != 0) {
    107		DRM_ERROR("tried to disable vblank on non-existent crtc %u\n",
    108			  pipe);
    109	}
    110
    111	/* Do *NOT* disable the vertical refresh interrupt.  MGA doesn't have
    112	 * a nice hardware counter that tracks the number of refreshes when
    113	 * the interrupt is disabled, and the kernel doesn't know the refresh
    114	 * rate to calculate an estimate.
    115	 */
    116	/* MGA_WRITE(MGA_IEN, MGA_VLINEIEN | MGA_SOFTRAPEN); */
    117}
    118
    119void mga_driver_fence_wait(struct drm_device *dev, unsigned int *sequence)
    120{
    121	drm_mga_private_t *dev_priv = (drm_mga_private_t *) dev->dev_private;
    122	unsigned int cur_fence;
    123
    124	/* Assume that the user has missed the current sequence number
    125	 * by about a day rather than she wants to wait for years
    126	 * using fences.
    127	 */
    128	wait_event_timeout(dev_priv->fence_queue,
    129		    (((cur_fence = atomic_read(&dev_priv->last_fence_retired))
    130		      - *sequence) <= (1 << 23)),
    131		    msecs_to_jiffies(3000));
    132
    133	*sequence = cur_fence;
    134}
    135
    136void mga_driver_irq_preinstall(struct drm_device *dev)
    137{
    138	drm_mga_private_t *dev_priv = (drm_mga_private_t *) dev->dev_private;
    139
    140	/* Disable *all* interrupts */
    141	MGA_WRITE(MGA_IEN, 0);
    142	/* Clear bits if they're already high */
    143	MGA_WRITE(MGA_ICLEAR, ~0);
    144}
    145
    146int mga_driver_irq_postinstall(struct drm_device *dev)
    147{
    148	drm_mga_private_t *dev_priv = (drm_mga_private_t *) dev->dev_private;
    149
    150	init_waitqueue_head(&dev_priv->fence_queue);
    151
    152	/* Turn on soft trap interrupt.  Vertical blank interrupts are enabled
    153	 * in mga_enable_vblank.
    154	 */
    155	MGA_WRITE(MGA_IEN, MGA_SOFTRAPEN);
    156	return 0;
    157}
    158
    159void mga_driver_irq_uninstall(struct drm_device *dev)
    160{
    161	drm_mga_private_t *dev_priv = (drm_mga_private_t *) dev->dev_private;
    162	if (!dev_priv)
    163		return;
    164
    165	/* Disable *all* interrupts */
    166	MGA_WRITE(MGA_IEN, 0);
    167
    168	dev->irq_enabled = false;
    169}