04f705ac7d3003dc6a37740d7a2703e59b5e04b1
[oweals/openwrt.git] /
1 From 82abb69d99441fde0d3c5400131aa1d1565f2f3d Mon Sep 17 00:00:00 2001
2 From: Eric Anholt <eric@anholt.net>
3 Date: Mon, 14 Jan 2019 12:35:43 -0800
4 Subject: [PATCH 580/782] drm/v3d: Skip MMU flush if the device is currently
5  off.
6
7 If it's off, we know it will be reset on poweron, so the MMU won't
8 have any TLB cached from before this point.  Avoids failed waits for
9 MMU flush to reply.
10
11 Signed-off-by: Eric Anholt <eric@anholt.net>
12 (cherry picked from commit 3ee4e2e0a9e9587eacbb69b067bbc72ab2cdc47b)
13 ---
14  drivers/gpu/drm/v3d/v3d_mmu.c | 13 +++++++++++++
15  1 file changed, 13 insertions(+)
16
17 --- a/drivers/gpu/drm/v3d/v3d_mmu.c
18 +++ b/drivers/gpu/drm/v3d/v3d_mmu.c
19 @@ -18,6 +18,8 @@
20   * each client.  This is not yet implemented.
21   */
22  
23 +#include <linux/pm_runtime.h>
24 +
25  #include "v3d_drv.h"
26  #include "v3d_regs.h"
27  
28 @@ -34,6 +36,14 @@ static int v3d_mmu_flush_all(struct v3d_
29  {
30         int ret;
31  
32 +       /* Keep power on the device on until we're done with this
33 +        * call, but skip the flush if the device is off and will be
34 +        * reset when powered back on.
35 +        */
36 +       ret = pm_runtime_get_if_in_use(v3d->dev);
37 +       if (ret == 0)
38 +               return 0;
39 +
40         /* Make sure that another flush isn't already running when we
41          * start this one.
42          */
43 @@ -61,6 +71,9 @@ static int v3d_mmu_flush_all(struct v3d_
44         if (ret)
45                 dev_err(v3d->dev, "MMUC flush wait idle failed\n");
46  
47 +       pm_runtime_mark_last_busy(v3d->dev);
48 +       pm_runtime_put_autosuspend(v3d->dev);
49 +
50         return ret;
51  }
52