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  1. 31 3月, 2021 4 次提交
  3. 19 1月, 2021 1 次提交
  5. 22 12月, 2020 2 次提交
  7. 18 12月, 2020 1 次提交
    • L
      drm/edid: fix objtool warning in drm_cvt_modes() · d652d5f1
      由 Linus Torvalds 提交于 
      Commit 991fcb77 ("drm/edid: Fix uninitialized variable in
drm_cvt_modes()") just replaced one warning with another.

The original warning about a possibly uninitialized variable was due to
the compiler not being smart enough to see that the case statement
actually enumerated all possible cases.  And the initial fix was just to
add a "default" case that had a single "unreachable()", just to tell the
compiler that that situation cannot happen.

However, that doesn't actually fix the fundamental reason for the
problem: the compiler still doesn't see that the existing case
statements enumerate all possibilities, so the compiler will still
generate code to jump to that unreachable case statement.  It just won't
complain about an uninitialized variable any more.

So now the compiler generates code to our inline asm marker that we told
it would not fall through, and end end result is basically random.  We
have created a bridge to nowhere.

And then, depending on the random details of just exactly what the
compiler ends up doing, 'objtool' might end up complaining about the
conditional branches (for conditions that cannot happen, and that thus
will never be taken - but if the compiler was not smart enough to figure
that out, we can't expect objtool to do so) going off in the weeds.

So depending on how the compiler has laid out the result, you might see
something like this:

    drivers/gpu/drm/drm_edid.o: warning: objtool: do_cvt_mode() falls through to next function drm_mode_detailed.isra.0()

and now you have a truly inscrutable warning that makes no sense at all
unless you start looking at whatever random code the compiler happened
to generate for our bare "unreachable()" statement.

IOW, don't use "unreachable()" unless you have an _active_ operation
that generates code that actually makes it obvious that something is not
reachable (ie an UD instruction or similar).

Solve the "compiler isn't smart enough" problem by just marking one of
the cases as "default", so that even when the compiler doesn't otherwise
see that we've enumerated all cases, the compiler will feel happy and
safe about there always being a valid case that initializes the 'width'
variable.

This also generates better code, since now the compiler doesn't generate
comparisons for five different possibilities (the four real ones and the
one that can't happen), but just for the three real ones and "the rest"
(which is that last one).

A smart enough compiler that sees that we cover all the cases won't care.

Cc: Lyude Paul <lyude@redhat.com>
Cc: Ilia Mirkin <imirkin@alum.mit.edu>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      d652d5f1
  9. 07 11月, 2020 1 次提交
  11. 30 10月, 2020 1 次提交
  13. 27 10月, 2020 1 次提交
  15. 23 9月, 2020 1 次提交
  17. 17 9月, 2020 1 次提交
  19. 20 7月, 2020 1 次提交
    • S
      drm: core: Convert device logging to drm_* functions. · 6d45fff5
      由 Suraj Upadhyay 提交于 
      Convert device logging with dev_* functions into drm_* functions.

The patch has been generated with the coccinelle script below.
The script focuses on instances of dev_* functions where the drm device
context is clearly visible in its arguments.

@@expression E1; expression list E2; @@
-dev_warn(E1->dev, E2)
+drm_warn(E1, E2)

@@expression E1; expression list E2; @@
-dev_info(E1->dev, E2)
+drm_info(E1, E2)

@@expression E1; expression list E2; @@
-dev_err(E1->dev, E2)
+drm_err(E1, E2)

@@expression E1; expression list E2; @@
-dev_info_once(E1->dev, E2)
+drm_info_once(E1, E2)

@@expression E1; expression list E2; @@
-dev_notice_once(E1->dev, E2)
+drm_notice_once(E1, E2)

@@expression E1; expression list E2; @@
-dev_warn_once(E1->dev, E2)
+drm_warn_once(E1, E2)

@@expression E1; expression list E2; @@
-dev_err_once(E1->dev, E2)
+drm_err_once(E1, E2)

@@expression E1; expression list E2; @@
-dev_err_ratelimited(E1->dev, E2)
+drm_err_ratelimited(E1, E2)

@@expression E1; expression list E2; @@
-dev_dbg(E1->dev, E2)
+drm_dbg(E1, E2)
Signed-off-by: NSuraj Upadhyay <usuraj35@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200718150955.GA23103@blackclown
      6d45fff5
  21. 17 7月, 2020 1 次提交
  23. 10 7月, 2020 3 次提交
  25. 02 7月, 2020 1 次提交
  27. 30 6月, 2020 2 次提交
  29. 24 6月, 2020 1 次提交
  31. 27 5月, 2020 1 次提交
    • V
      drm: Nuke mode->vrefresh · 0425662f
      由 Ville Syrjälä 提交于 
      Get rid of mode->vrefresh and just calculate it on demand. Saves
a bit of space and avoids the cached value getting out of sync
with reality.

Mostly done with cocci, with the following manual fixups:
- Remove the now empty loop in drm_helper_probe_single_connector_modes()
- Fix __MODE() macro in ch7006_mode.c
- Fix DRM_MODE_ARG() macro in drm_modes.h
- Remove leftover comment from samsung_s6d16d0_mode
- Drop the TODO

@@
@@
struct drm_display_mode {
	...
-	int vrefresh;
	...
};

@@
identifier N;
expression E;
@@
struct drm_display_mode N = {
-	.vrefresh = E
};

@@
identifier N;
expression E;
@@
struct drm_display_mode N[...] = {
...,
{
-	.vrefresh = E
}
,...
};

@@
expression E;
@@
{
	DRM_MODE(...),
-	.vrefresh = E,
}

@@
identifier M, R;
@@
int drm_mode_vrefresh(const struct drm_display_mode *M)
{
  ...
- if (M->vrefresh > 0)
- 	R = M->vrefresh;
- else
  if (...) {
  ...
  }
  ...
}

@@
struct drm_display_mode *p;
expression E;
@@
(
- p->vrefresh = E;
|
- p->vrefresh
+ drm_mode_vrefresh(p)
)

@@
struct drm_display_mode s;
expression E;
@@
(
- s.vrefresh = E;
|
- s.vrefresh
+ drm_mode_vrefresh(&s)
)

@@
expression E;
@@
- drm_mode_vrefresh(E) ? drm_mode_vrefresh(E) : drm_mode_vrefresh(E)
+ drm_mode_vrefresh(E)

@find_substruct@
identifier X;
identifier S;
@@
struct X {
...
	struct drm_display_mode S;
...
};

@@
identifier find_substruct.S;
expression E;
identifier I;
@@
{
.S = {
-	.vrefresh = E
}
}

@@
identifier find_substruct.S;
identifier find_substruct.X;
expression E;
identifier I;
@@
struct X I[...] = {
...,
.S = {
-	.vrefresh = E
}
,...
};

v2: Drop TODO
v3: Rebase
v4: Rebase

Cc: Andrzej Hajda <a.hajda@samsung.com>
Cc: Neil Armstrong <narmstrong@baylibre.com>
Cc: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
Cc: Jonas Karlman <jonas@kwiboo.se>
Cc: Jernej Skrabec <jernej.skrabec@siol.net>
Cc: Inki Dae <inki.dae@samsung.com>
Cc: Joonyoung Shim <jy0922.shim@samsung.com>
Cc: Seung-Woo Kim <sw0312.kim@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: CK Hu <ck.hu@mediatek.com>
Cc: Philipp Zabel <p.zabel@pengutronix.de>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Jerry Han <hanxu5@huaqin.corp-partner.google.com>
Cc: Icenowy Zheng <icenowy@aosc.io>
Cc: Jagan Teki <jagan@amarulasolutions.com>
Cc: Stefan Mavrodiev <stefan@olimex.com>
Cc: Robert Chiras <robert.chiras@nxp.com>
Cc: "Guido Günther" <agx@sigxcpu.org>
Cc: Purism Kernel Team <kernel@puri.sm>
Cc: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Cc: Vincent Abriou <vincent.abriou@st.com>
Cc: VMware Graphics <linux-graphics-maintainer@vmware.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Cc: linux-amlogic@lists.infradead.org
Cc: nouveau@lists.freedesktop.org
Reviewed-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: NEmil Velikov <emil.velikov@collabora.com>
Reviewed-by: NSam Ravnborg <sam@ravnborg.org>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200428171940.19552-4-ville.syrjala@linux.intel.com
      0425662f
  33. 20 5月, 2020 1 次提交
  35. 29 4月, 2020 1 次提交
  37. 24 4月, 2020 1 次提交
  39. 18 3月, 2020 7 次提交
  41. 16 3月, 2020 1 次提交
    • K
      drm/edid: Distribute switch variables for initialization · deec222e
      由 Kees Cook 提交于 
      Variables declared in a switch statement before any case statements
cannot be automatically initialized with compiler instrumentation (as
they are not part of any execution flow). With GCC's proposed automatic
stack variable initialization feature, this triggers a warning (and they
don't get initialized). Clang's automatic stack variable initialization
(via CONFIG_INIT_STACK_ALL=y) doesn't throw a warning, but it also
doesn't initialize such variables[1]. Note that these warnings (or silent
skipping) happen before the dead-store elimination optimization phase,
so even when the automatic initializations are later elided in favor of
direct initializations, the warnings remain.

To avoid these problems, lift such variables up into the next code
block.

drivers/gpu/drm/drm_edid.c: In function ‘drm_edid_to_eld’:
drivers/gpu/drm/drm_edid.c:4395:9: warning: statement will never be
executed [-Wswitch-unreachable]
 4395 |     int sad_count;
      |         ^~~~~~~~~

[1] https://bugs.llvm.org/show_bug.cgi?id=44916

v2: move into function block instead being switch-local (Ville Syrjälä)
Signed-off-by: NKees Cook <keescook@chromium.org>
[danvet: keep the changelog]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/202003060930.DDCCB6659@keescook
      deec222e
  43. 12 3月, 2020 1 次提交
    • M
      drm/edid: Add function to parse EDID descriptors for monitor range · a1d11d1e
      由 Manasi Navare 提交于 
      Adaptive Sync is a VESA feature so add a DRM core helper to parse
the EDID's detailed descritors to obtain the adaptive sync monitor range.
Store this info as part fo drm_display_info so it can be used
across all drivers.
This part of the code is stripped out of amdgpu's function
amdgpu_dm_update_freesync_caps() to make it generic and be used
across all DRM drivers

v6:
* Call it monitor_range (Ville)
v5:
* Use the renamed flags
v4:
* Use is_display_descriptor() (Ville)
* Name the monitor range flags (Ville)
v3:
* Remove the edid parsing restriction for just DP (Nicholas)
* Use drm_for_each_detailed_block (Ville)
* Make the drm_get_adaptive_sync_range function static (Harry, Jani)
v2:
* Change vmin and vmax to use u8 (Ville)
* Dont store pixel clock since that is just a max dotclock
and not related to VRR mode (Manasi)

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Harry Wentland <harry.wentland@amd.com>
Cc: Clinton A Taylor <clinton.a.taylor@intel.com>
Cc: Kazlauskas Nicholas <Nicholas.Kazlauskas@amd.com>
Signed-off-by: NManasi Navare <manasi.d.navare@intel.com>
Reviewed-by: NNicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200310231651.13841-2-manasi.d.navare@intel.com
      a1d11d1e
  45. 26 2月, 2020 2 次提交
  47. 15 2月, 2020 3 次提交