fbdev: mmp: Annotate struct mmp_path with __counted_by

Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).

As found with Coccinelle[1], add __counted_by for struct mmp_path.

[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci

Cc: Helge Deller <deller@gmx.de>
Cc: linux-fbdev@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Helge Deller <deller@gmx.de>

video: Replace zero-length array with flexible-array member

The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
int stuff;
struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200221160005.GA13552@embeddedor

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 13

Based on 2 normalized pattern(s):

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 see http www gnu org licenses

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 [based]
[from] [clk] [highbank] [c] you should have received a copy of the
gnu general public license along with this program if not see http
www gnu org licenses

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 355 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Jilayne Lovejoy <opensource@jilayne.com>
Reviewed-by: Steve Winslow <swinslow@gmail.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190519154041.837383322@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

video: mmp: add pitch info in mmp_win structure

Add pitch length info of graphics/video layer, pitch is used
to represent line length in byte, the usage depends on pix_fmt.
If the fmt is YUV, the pitch[0] will be Y length,pitch[1]
will be U length, pitch[2] will be V lenth.
If the fmt is RGB, the picth[0] will be line lenth, and
pitch[1]/pitch[2] will be 0 and not be used.

Signed-off-by: Jing Xiang <jxiang@marvell.com>
Signed-off-by: Jett.Zhou <jtzhou@marvell.com>
Signed-off-by: Zhou Zhu <zzhu3@marvell.com>
Reviewed-by: Daniel Drake <dsd@laptop.org>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

video: mmp: rb swap setting update for mmp display

We could set rb swap in two modules: DMA controler input part and
dsi interface output part.
DMA input part is based on pix_fmt to set rbswap, dsi output interface
part will set rbswap based on platform dsi_rbswap configuration.

This patch include below change and enhancement:

1) The input format which support rbswap is based on RGB format,
eg. RGB565 indicates the source data in memory is that Red is [15~11],
Green is [10~5], Blue is [4:0], Red is MSB, Blue is LSB, but for the
display dma input default setting(rbswap = 0), it only support Blue
is [15~11], Green is [10~5], Red is [4:0], Red is LSB, Blue is MSB,
so for this format(RGB565), display controller need to set rbswap
= 1 and it can support the MSB/LSB correctly.
BGR/YUV format will not set it in mmp display driver.

2) The dsi output part of rbswap is depend on dsi_rbswap which is
defined in specific platfrom. For output dsi interface, it has this
feature to do rbswap again if it needs specifc byte sequence of RGB
byte for DSI panel.
eg. If display content is set RGB565 in memory and DMA input part set
rbswap in driver to support Red as MSB , Blue LSB, but dsi panel only
support Red as LSB, Blue as MSB, then it can use this feature.
If there is no this requirement of panel, this dsi output part is not
needed.

Signed-off-by: Guoqing Li <ligq@marvell.com>
Signed-off-by: Jett.Zhou <jtzhou@marvell.com>
Signed-off-by: Zhou Zhu <zzhu3@marvell.com>
Reviewed-by: Daniel Drake <dsd@laptop.org>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

video: mmp display subsystem

Add mmp display subsystem to support Marvell MMP display controllers.

This subsystem contains 4 parts:
--fb folder
--core.c
--hw folder
--panel folder

1. fb folder contains implementation of fb. fb get path and overlay
from common interface and operates on these structures.

2. core.c provides common interface for a hardware abstraction. Major
parts of this interface are:

a) Path: path is a output device connected to a panel or HDMI TV. Main
operations of the path is set/get timing/output color. fb operates
output device through path structure.

b) Ovly: Ovly is a buffer shown on the path.

Ovly describes frame buffer and its source/destination size, offset,
input color, buffer address, z-order, and so on. Each fb device maps
to one overlay.

3. hw folder contains implementation of hardware operations defined by
core.c. It registers paths for fb use.

4. panel folder contains implementation of panels. It's connected to
path. Panel drivers would also regiester panels and linked to path
when probe.

Signed-off-by: Zhou Zhu <zzhu3@marvell.com>
Signed-off-by: Lisa Du <cldu@marvell.com>
Cc: Guoqing Li <ligq@marvell.com>
Acked-by: Haojian Zhuang <haojian.zhuang@gmail.com>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>