/*
 * Definitions for AUO-K190X framebuffer drivers
 *
 * Copyright (C) 2012 Heiko Stuebner <heiko@sntech.de>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#ifndef _LINUX_VIDEO_AUO_K190XFB_H_
#define _LINUX_VIDEO_AUO_K190XFB_H_

/* Controller standby command needs a param */
#define AUOK190X_QUIRK_STANDBYPARAM	(1 << 0)

/* Controller standby is completely broken */
#define AUOK190X_QUIRK_STANDBYBROKEN	(1 << 1)

/*
 * Resolutions for the displays
 */
#define AUOK190X_RESOLUTION_800_600		0
#define AUOK190X_RESOLUTION_1024_768		1
#define AUOK190X_RESOLUTION_600_800		4
#define AUOK190X_RESOLUTION_768_1024		5

/*
 * struct used by auok190x. board specific stuff comes from *board
 */
struct auok190xfb_par {
	struct fb_info *info;
	struct auok190x_board *board;

	struct regulator *regulator;

	struct mutex io_lock;
	struct delayed_work work;
	wait_queue_head_t waitq;
	int resolution;
	int rotation;
	int consecutive_threshold;
	int update_cnt;

	/* panel and controller informations */
	int epd_type;
	int panel_size_int;
	int panel_size_float;
	int panel_model;
	int tcon_version;
	int lut_version;

	/* individual controller callbacks */
	void (*update_partial)(struct auok190xfb_par *par, u16 y1, u16 y2);
	void (*update_all)(struct auok190xfb_par *par);
	bool (*need_refresh)(struct auok190xfb_par *par);
	void (*init)(struct auok190xfb_par *par);
	void (*recover)(struct auok190xfb_par *par);

	int update_mode; /* mode to use for updates */
	int last_mode; /* update mode last used */
	int flash;

	/* power management */
	int autosuspend_delay;
	bool standby;
	bool manual_standby;
};

/**
 * Board specific platform-data
 * @init:		initialize the controller interface
 * @cleanup:		cleanup the controller interface
 * @wait_for_rdy:	wait until the controller is not busy anymore
 * @set_ctl:		change an interface control
 * @set_hdb:		write a value to the data register
 * @get_hdb:		read a value from the data register
 * @setup_irq:		method to setup the irq handling on the busy gpio
 * @gpio_nsleep:	sleep gpio
 * @gpio_nrst:		reset gpio
 * @gpio_nbusy:		busy gpio
 * @resolution:		one of the AUOK190X_RESOLUTION constants
 * @rotation:		rotation of the framebuffer
 * @quirks:		controller quirks to honor
 * @fps:		frames per second for defio
 */
struct auok190x_board {
	int (*init)(struct auok190xfb_par *);
	void (*cleanup)(struct auok190xfb_par *);
	int (*wait_for_rdy)(struct auok190xfb_par *);

	void (*set_ctl)(struct auok190xfb_par *, unsigned char, u8);
	void (*set_hdb)(struct auok190xfb_par *, u16);
	u16 (*get_hdb)(struct auok190xfb_par *);

	int (*setup_irq)(struct fb_info *);

	int gpio_nsleep;
	int gpio_nrst;
	int gpio_nbusy;

	int resolution;
	int quirks;
	int fps;
};

#endif
>
</td></tr></table>
<div class='path'>path: <a href='/cgit.cgi/linux/net-next.git/commit/?id=39cb2c9a316e77f6dfba96c543e55b6672d5a37e'>root</a>/<a href='/cgit.cgi/linux/net-next.git/commit/tools?id=39cb2c9a316e77f6dfba96c543e55b6672d5a37e'>tools</a>/<a href='/cgit.cgi/linux/net-next.git/commit/tools/perf?id=39cb2c9a316e77f6dfba96c543e55b6672d5a37e'>perf</a>/<a href='/cgit.cgi/linux/net-next.git/commit/tools/perf/pmu-events?id=39cb2c9a316e77f6dfba96c543e55b6672d5a37e'>pmu-events</a>/<a href='/cgit.cgi/linux/net-next.git/commit/tools/perf/pmu-events/arch?id=39cb2c9a316e77f6dfba96c543e55b6672d5a37e'>arch</a>/<a href='/cgit.cgi/linux/net-next.git/commit/tools/perf/pmu-events/arch/x86?id=39cb2c9a316e77f6dfba96c543e55b6672d5a37e'>x86</a>/<a href='/cgit.cgi/linux/net-next.git/commit/tools/perf/pmu-events/arch/x86/nehalemex?id=39cb2c9a316e77f6dfba96c543e55b6672d5a37e'>nehalemex</a>/<a href='/cgit.cgi/linux/net-next.git/commit/tools/perf/pmu-events/arch/x86/nehalemex/pipeline.json?id=39cb2c9a316e77f6dfba96c543e55b6672d5a37e'>pipeline.json</a></div><div class='content'><div class='cgit-panel'><b>diff options</b><form method='get'><input type='hidden' name='id' value='39cb2c9a316e77f6dfba96c543e55b6672d5a37e'/><table><tr><td colspan='2'/></tr><tr><td class='label'>context:</td><td class='ctrl'><select name='context' onchange='this.form.submit();'><option value='1'>1</option><option value='2'>2</option><option value='3' selected='selected'>3</option><option value='4'>4</option><option value='5'>5</option><option value='6'>6</option><option value='7'>7</option><option value='8'>8</option><option value='9'>9</option><option value='10'>10</option><option value='15'>15</option><option value='20'>20</option><option value='25'>25</option><option value='30'>30</option><option value='35'>35</option><option value='40'>40</option></select></td></tr><tr><td class='label'>space:</td><td class='ctrl'><select name='ignorews' onchange='this.form.submit();'><option value='0' selected='selected'>include</option><option value='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</option><option value='1'>ssdiff</option><option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><table summary='commit info' class='commit-info'>
<tr><th>author</th><td>Linus Torvalds &lt;torvalds@linux-foundation.org&gt;</td><td class='right'>2017-01-29 13:50:06 -0800</td></tr>
<tr><th>committer</th><td>Linus Torvalds &lt;torvalds@linux-foundation.org&gt;</td><td class='right'>2017-01-29 13:50:06 -0800</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/tools/perf/pmu-events/arch/x86/nehalemex/pipeline.json?id=39cb2c9a316e77f6dfba96c543e55b6672d5a37e'>39cb2c9a316e77f6dfba96c543e55b6672d5a37e</a> (<a href='/cgit.cgi/linux/net-next.git/patch/tools/perf/pmu-events/arch/x86/nehalemex/pipeline.json?id=39cb2c9a316e77f6dfba96c543e55b6672d5a37e'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?id=39cb2c9a316e77f6dfba96c543e55b6672d5a37e'>98fe974ee4e20121253de7f61fc8d01bdb3821c1</a> /<a href='/cgit.cgi/linux/net-next.git/tree/tools/perf/pmu-events/arch/x86/nehalemex/pipeline.json?id=39cb2c9a316e77f6dfba96c543e55b6672d5a37e'>tools/perf/pmu-events/arch/x86/nehalemex/pipeline.json</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/tools/perf/pmu-events/arch/x86/nehalemex/pipeline.json?id=2c5d9555d6d937966d79d4c6529a5f7b9206e405'>2c5d9555d6d937966d79d4c6529a5f7b9206e405</a> (<a href='/cgit.cgi/linux/net-next.git/diff/tools/perf/pmu-events/arch/x86/nehalemex/pipeline.json?id=39cb2c9a316e77f6dfba96c543e55b6672d5a37e&amp;id2=2c5d9555d6d937966d79d4c6529a5f7b9206e405'>diff</a>)</td></tr></table>
<div class='commit-subject'>drm/i915: Check for NULL i915_vma in intel_unpin_fb_obj()</div><div class='commit-msg'>I've seen this trigger twice now, where the i915_gem_object_to_ggtt()
call in intel_unpin_fb_obj() returns NULL, resulting in an oops
immediately afterwards as the (inlined) call to i915_vma_unpin_fence()
tries to dereference it.

It seems to be some race condition where the object is going away at
shutdown time, since both times happened when shutting down the X
server.  The call chains were different:

 - VT ioctl(KDSETMODE, KD_TEXT):

    intel_cleanup_plane_fb+0x5b/0xa0 [i915]
    drm_atomic_helper_cleanup_planes+0x6f/0x90 [drm_kms_helper]
    intel_atomic_commit_tail+0x749/0xfe0 [i915]
    intel_atomic_commit+0x3cb/0x4f0 [i915]
    drm_atomic_commit+0x4b/0x50 [drm]
    restore_fbdev_mode+0x14c/0x2a0 [drm_kms_helper]
    drm_fb_helper_restore_fbdev_mode_unlocked+0x34/0x80 [drm_kms_helper]
    drm_fb_helper_set_par+0x2d/0x60 [drm_kms_helper]
    intel_fbdev_set_par+0x18/0x70 [i915]
    fb_set_var+0x236/0x460
    fbcon_blank+0x30f/0x350
    do_unblank_screen+0xd2/0x1a0
    vt_ioctl+0x507/0x12a0
    tty_ioctl+0x355/0xc30
    do_vfs_ioctl+0xa3/0x5e0
    SyS_ioctl+0x79/0x90
    entry_SYSCALL_64_fastpath+0x13/0x94

 - i915 unpin_work workqueue:

    intel_unpin_work_fn+0x58/0x140 [i915]
    process_one_work+0x1f1/0x480
    worker_thread+0x48/0x4d0
    kthread+0x101/0x140

and this patch purely papers over the issue by adding a NULL pointer
check and a WARN_ON_ONCE() to avoid the oops that would then generally
make the machine unresponsive.

Other callers of i915_gem_object_to_ggtt() seem to also check for the
returned pointer being NULL and warn about it, so this clearly has
happened before in other places.

[ Reported it originally to the i915 developers on Jan 8, applying the
  ugly workaround on my own now after triggering the problem for the
  second time with no feedback.

  This is likely to be the same bug reported as

     https://bugs.freedesktop.org/show_bug.cgi?id=98829
     https://bugs.freedesktop.org/show_bug.cgi?id=99134

  which has a patch for the underlying problem, but it hasn't gotten to
  me, so I'm applying the workaround. ]

Cc: Daniel Vetter &lt;daniel.vetter@intel.com&gt;
Cc: Jani Nikula &lt;jani.nikula@linux.intel.com&gt;
Cc: Ville Syrjälä &lt;ville.syrjala@linux.intel.com&gt;
Cc: Chris Wilson &lt;chris@chris-wilson.co.uk&gt;
Cc: Maarten Lankhorst &lt;maarten.lankhorst@linux.intel.com&gt;
Cc: Tvrtko Ursulin &lt;tvrtko.ursulin@intel.com&gt;
Cc: Imre Deak &lt;imre.deak@intel.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=39cb2c9a316e77f6dfba96c543e55b6672d5a37e'>Diffstat</a> (limited to 'tools/perf/pmu-events/arch/x86/nehalemex/pipeline.json')</div><table summary='diffstat' class='diffstat'>