Revision 53292cdb066950611e5bc2e0eb109c7edb42af78 authored by Michel Thierry on 15 April 2015, 17:11:33 UTC, committed by Jani Nikula on 23 April 2015, 20:56:52 UTC
WaIdleLiteRestore is an execlists-only workaround, and requires the driver
to ensure that any context always has HEAD!=TAIL when attempting lite
restore.

Add two extra MI_NOOP instructions at the end of each request, but keep
the requests tail pointing before the MI_NOOPs. We may not need to
executed them, and this is why request->tail is sampled before adding
these extra instructions.

If we submit a context to the ELSP which has previously been submitted,
move the tail pointer past the MI_NOOPs. This ensures HEAD!=TAIL.

v2: Move overallocation to gen8_emit_request, and added note about
sampling request->tail in commit message (Chris).

v3: Remove redundant request->tail assignment in __i915_add_request, in
lrc mode this is already set in execlists_context_queue.
Do not add wa implementation details inside gem (Chris).

v4: Apply the wa whenever the req has been resubmitted and update
comment (Chris).

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Thomas Daniel <thomas.daniel@intel.com>
Signed-off-by: Michel Thierry <michel.thierry@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
1 parent 9535c47
Raw File
last.c
/*
 *  Advanced Linux Sound Architecture
 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
 *
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 *
 */

#include <linux/init.h>
#include <sound/core.h>

static int __init alsa_sound_last_init(void)
{
	int idx, ok = 0;
	
	printk(KERN_INFO "ALSA device list:\n");
	for (idx = 0; idx < SNDRV_CARDS; idx++)
		if (snd_cards[idx] != NULL) {
			printk(KERN_INFO "  #%i: %s\n", idx, snd_cards[idx]->longname);
			ok++;
		}
	if (ok == 0)
		printk(KERN_INFO "  No soundcards found.\n");
	return 0;
}

late_initcall_sync(alsa_sound_last_init);
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