staging: vc04_services: Re-add dependency on HAS_DMA to BCM2835_VCHIQ

Thanks to stubs for the NO_DMA=y case, drivers that use the DMA API can
be compile-tested on systems that do not support DMA. Hence the
dependency of BCM2835_VCHIQ on HAS_DMA was dropped to increase compile
coverage.

Unfortunately compilers became smarter, leading to new failures.
E.g. for a CONFIG_SUN3=y allmodconfig kernel with gcc 9.4.0:

drivers/staging/vc04_services/interface/vchiq_arm/vchiq_2835_arm.c: In function ‘free_pagelist’:
arch/m68k/include/asm/string.h:72:25: warning: argument 2 null where non-null expected [-Wnonnull]
72 | #define memcpy(d, s, n) __builtin_memcpy(d, s, n)
| ^~~~~~~~~~~~~~~~~~~~~~~~~
drivers/staging/vc04_services/interface/vchiq_arm/vchiq_2835_arm.c:614:4: note: in expansion of macro ‘memcpy’
614 | memcpy((char *)kmap(pages[0]) +
| ^~~~~~
arch/m68k/include/asm/string.h:72:25: note: in a call to built-in function ‘__builtin_memcpy’
72 | #define memcpy(d, s, n) __builtin_memcpy(d, s, n)
| ^~~~~~~~~~~~~~~~~~~~~~~~~
drivers/staging/vc04_services/interface/vchiq_arm/vchiq_2835_arm.c:614:4: note: in expansion of macro ‘memcpy’
614 | memcpy((char *)kmap(pages[0]) +
| ^~~~~~

This happens because the compiler can trace back the source pointer to a
allocation by dma_alloc_attrs(), which always returns NULL if NO_DMA=y.

Avoid this reinstating the dependency of the BCM2835_VCHIQ symbol on
HAS_DMA, and by restricting the selection of BCM2835_VCHIQ.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/da55bd87eebf1a969dc8ccd807843319833f6c40.1650888813.git.geert@linux-m68k.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: vchiq: Add details to Kconfig help texts

Add some details to the Kconfig definitions of $CONFIG_VCHIQ_CDEV and
$CONFIG_BCM2835_VCHIQ to help make the motive behind the configs a bit
more clear.

Reviewed-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Ojaswin Mujoo <ojaswin98@gmail.com>
Link: https://lore.kernel.org/r/ab88d3222088aca29a319147b50a9d1e9f0f8b81.1627925241.git.ojaswin98@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: vchiq: Set $CONFIG_BCM2835_VCHIQ to imply $CONFIG_VCHIQ_CDEV

Before $CONFIG_VCHIQ_CDEV was defined, the vchiq cdev used to be created
unconditionally when CONFIG_BCM2835_VCHIQ=y. When an earlier commit
introduced the new config, its default behavior was set to disabled,
which might surprise some unsuspecting users. Hence, modify
CONFIG_BCM2835_VCHIQ to imply CONFIG_VCHIQ_CDEV

Reviewed-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Ojaswin Mujoo <ojaswin98@gmail.com>
Link: https://lore.kernel.org/r/da53207b24bc37f166b05c6835087becdc6b5b4d.1627925241.git.ojaswin98@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: vchiq: Make creation of vchiq cdev optional

Before this commit, vchiq cdev (/dev/vchiq) was always created during
platform initialization. Introduce a new Kconfig option
CONFIG_VCHIQ_CDEV which determines if the cdev will be created or not.

Reviewed-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Ojaswin Mujoo <ojaswin98@gmail.com>
Link: https://lore.kernel.org/r/846c424dd4aae14d1cc28c8f30877a06e2b7dd10.1626882325.git.ojaswin98@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: bcm2835: Break MMAL support out from camera

The BCM2835 camera host is currently the only component that uses the
VCHIQ MMAL interface. This will soon change with the upporting of
BCM2835 ISP, which make use of the same interface.

Break VCHIQ MMAL interface support out from camera host directory to
make it possible for the ISP driver to use it as well.

The only modification to the existing mmal code is the introduction of
EXPORT_SYMBOL() for symbols required by bcm2835-camera and the addition
of the module author and licenses.

Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Link: https://lore.kernel.org/r/20200623164235.29566-2-nsaenzjulienne@suse.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: add missing SPDX lines to Kconfig files

There are a few remaining drivers/staging/*/Kconfig files that do not
have SPDX identifiers in them. Add the correct GPL-2.0 identifier to
them to make scanning tools happy.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: vc04_services: Remove depends on HAS_DMA in case of platform dependency

Remove dependencies on HAS_DMA where a Kconfig symbol depends on another
symbol that implies HAS_DMA, and, optionally, on "|| COMPILE_TEST".
In most cases this other symbol is an architecture or platform specific
symbol, or PCI.

Generic symbols and drivers without platform dependencies keep their
dependencies on HAS_DMA, to prevent compiling subsystems or drivers that
cannot work anyway.

This simplifies the dependencies, and allows to improve compile-testing.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: vc04_services: remove BCM2835_VCHIQ_SUPPORT_MEMDUMP

BCM2835_VCHIQ_SUPPORT_MEMDUMP lets you look through any user memory.
That's too big of an information leak from a security perspective. The
debugging dumps need to be more specific to this driver.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: vc04_services: make BCM_VIDEOCORE tristate

Adding the 'bool' symbol brought back a randconfig build bug that
I had fixed before:

drivers/staging/built-in.o: In function `vchiq_probe':
(.text+0x1da30): undefined reference to `rpi_firmware_get'
drivers/staging/built-in.o: In function `vchiq_platform_init':
(.text+0x27494): undefined reference to `rpi_firmware_property'

The problem is that when RASPBERRYPI_FIRMWARE is a loadable module,
but BCM2835_VCHIQ can again be built-in. Making BCM_VIDEOCORE
itself tristate will make Kconfig honor the dependency correctly.

Fixes: 6bbfe4a76158 ("staging: vc04_services: Create new BCM_VIDEOCORE setting for VideoCore services.")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: vchiq_arm: Disable ability to dump memory by default

vc04_services has an ioctl interface to dump arbitrary memory
to a custom debug log. This is typically only needed by
diagnostic tools, and can potentially be a security issue
if the devtmpfs node doesn't have adequate permissions set.

Since the ability to dump memory still has debugging value,
create a new build configuration and disable the feature
by default.

Signed-off-by: Michael Zoran <mzoran@crowfest.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging/vc04_services: add CONFIG_OF dependency

After several hours of debugging this obviously bogus but elaborate
gcc-7.0.1 warning,

drivers/staging/vc04_services/interface/vchiq_arm/vchiq_2835_arm.c: In function 'vchiq_complete_bulk':
drivers/staging/vc04_services/interface/vchiq_arm/vchiq_2835_arm.c:603:4: error: argument 2 null where non-null expected [-Werror=nonnull]
memcpy((char *)page_address(pages[0]) +
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
pagelist->offset,
~~~~~~~~~~~~~~~~~
fragments,
~~~~~~~~~~
head_bytes);
~~~~~~~~~~~
In file included from include/linux/string.h:18:0,
from include/linux/bitmap.h:8,
from include/linux/cpumask.h:11,
from include/linux/interrupt.h:9,
from drivers/staging/vc04_services/interface/vchiq_arm/vchiq_2835_arm.c:37:
arch/arm/include/asm/string.h:16:15: note: in a call to function 'memcpy' declared here
extern void * memcpy(void *, const void *, __kernel_size_t) __nocapture(2);
^~~~~~

I have concluded that gcc was technically right in the first place:

vchiq_complete_bulk is an externally visible function that calls
free_pagelist(), which in turn derives a pointer from the global
g_fragments_base variable.

g_fragments_base is initialized in vchiq_platform_init(), but
we only get there if of_property_read_u32() successfully reads the
cache line size. When CONFIG_OF is disabled, this always fails, and
g_fragments_base is guaranteed to be NULL when vchiq_complete_bulk()
gets called.

This adds a CONFIG_OF Kconfig dependency, which is also technically correct
but nonobvious, and thus seems like a good fit for the warning.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: vc04_services: Create new BCM_VIDEOCORE setting for VideoCore services.

Create a new memuconfig for Broadcom VideoCore services
since VideoCore is a general term used by Broadcom for a
large family of products that includes more then the BCM2835.

Signed-off-by: Michael Zoran <mzoran@crowfest.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: bcm2835-camera: Move driver under vc04_services

The bcm2835-camera driver is part of v04_services, so it makes
sense for it to be located under vc04_services to make
configuration clearer.

Signed-off-by: Michael Zoran <mzoran@crowfest.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: bcm2835-audio: Move driver under vc04_services

The bcm2835-audio driver is part of v04_services, so it makes
sense for it to be located under vc04_services to make
configuration clearer.

Signed-off-by: Michael Zoran <mzoran@crowfest.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: vc04_services: add HAS_DMA dependancy

We need DMA for this, otherwise the build breaks, so fix this up.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Lee Jones <lee@kernel.org>
Cc: Eric Anholt <eric@anholt.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: vc04_services: clarify firmware dependency

The raspberrypi-firmware driver may be built as a loadable module,
which causes a link-time failure if the vc04_services driver is
built-in during compile-testing:

drivers/staging/vc04_services/vchiq.o: In function `vchiq_probe':
vchiq_connected.c:(.text.vchiq_probe+0x2c): undefined reference to `rpi_firmware_get'
drivers/staging/vc04_services/vchiq.o: In function `vchiq_platform_init':
vchiq_connected.c:(.text.vchiq_platform_init+0x1f0): undefined reference to `rpi_firmware_property'

This extends the dependency list to ensure the firmware is either
reachable, or completely disabled in case of compile-testing.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: vc04_services: add CONFIG_COMPILE_TEST ability

It would be nice to be able to build this code on other platforms other
than only the RPi, so add some empty macros to allow this to happen, and
turn off BROKEN as the code can now build properly thanks to Michael's
work.

Cc: Michael Zoran <mzoran@crowfest.net>
Cc: Daniel Stone <daniels@collabora.com>
Cc: "Noralf Trønnes" <noralf@tronnes.org>
Cc: Pranith Kumar <bobby.prani@gmail.com>
Cc: popcornmix <popcornmix@gmail.com>
Cc: Eric Anholt <eric@anholt.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: vc04_services: use bcm2835 consequently

The naming bcm2708 is used only in the vendor kernel, so better
replace it with bcm2835 which is used in mainline in order
to avoid any confusion.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: add bcm2708 vchiq driver

Signed-off-by: popcornmix <popcornmix@gmail.com>

vchiq: create_pagelist copes with vmalloc memory

Signed-off-by: Daniel Stone <daniels@collabora.com>

vchiq: fix the shim message release

Signed-off-by: Daniel Stone <daniels@collabora.com>

vchiq: export additional symbols

Signed-off-by: Daniel Stone <daniels@collabora.com>

VCHIQ: Make service closure fully synchronous (drv)

This is one half of a two-part patch, the other half of which is to
the vchiq_lib user library. With these patches, calls to
vchiq_close_service and vchiq_remove_service won't return until any
associated callbacks have been delivered to the callback thread.

VCHIQ: Add per-service tracing

The new service option VCHIQ_SERVICE_OPTION_TRACE is a boolean that
toggles tracing for the specified service.

This commit also introduces vchi_service_set_option and the associated
option VCHI_SERVICE_OPTION_TRACE.

vchiq: Make the synchronous-CLOSE logic more tolerant

vchiq: Move logging control into debugfs

vchiq: Take care of a corner case tickled by VCSM

Closing a connection that isn't fully open requires care, since one
side does not know the other side's port number. Code was present to
handle the case where a CLOSE is sent immediately after an OPEN, i.e.
before the OPENACK has been received, but this was incorrectly being
used when an OPEN from a client using port 0 was rejected.

(In the observed failure, the host was attempting to use the VCSM
service, which isn't present in the 'cutdown' firmware. The failure
was intermittent because sometimes the keepalive service would
grab port 0.)

This case can be distinguished because the client's remoteport will
still be VCHIQ_PORT_FREE, and the srvstate will be OPENING. Either
condition is sufficient to differentiate it from the special case
described above.

vchiq: Avoid high load when blocked and unkillable

vchiq: Include SIGSTOP and SIGCONT in list of signals not-masked by vchiq to allow gdb to work

vchiq_arm: Complete support for SYNCHRONOUS mode

vchiq: Remove inline from suspend/resume

vchiq: Allocation does not need to be atomic

vchiq: Fix wrong condition check

The log level is checked from within the log call. Remove the check in the call.

Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>

BCM270x: Add vchiq device to platform file and Device Tree

Prepare to turn the vchiq module into a driver.

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>

bcm2708: vchiq: Add Device Tree support

Turn vchiq into a driver and stop hardcoding resources.
Use devm_* functions in probe path to simplify cleanup.
A global variable is used to hold the register address. This is done
to keep this patch as small as possible.
Also make available on ARCH_BCM2835.
Based on work by Lubomir Rintel.

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>

vchiq: Change logging level for inbound data

vchiq_arm: Two cacheing fixes

1) Make fragment size vary with cache line size
Without this patch, non-cache-line-aligned transfers may corrupt
(or be corrupted by) adjacent data structures.

Both ARM and VC need to be updated to enable this feature. This is
ensured by having the loader apply a new DT parameter -
cache-line-size. The existence of this parameter guarantees that the
kernel is capable, and the parameter will only be modified from the
safe default if the loader is capable.

2) Flush/invalidate vmalloc'd memory, and invalidate after reads

vchiq: fix NULL pointer dereference when closing driver

The following code run as root will cause a null pointer dereference oops:

int fd = open("/dev/vc-cma", O_RDONLY);
if (fd < 0)
err(1, "open failed");
(void)close(fd);

[ 1704.877721] Unable to handle kernel NULL pointer dereference at virtual address 00000000
[ 1704.877725] pgd = b899c000
[ 1704.877736] [00000000] *pgd=37fab831, *pte=00000000, *ppte=00000000
[ 1704.877748] Internal error: Oops: 817 [#1] PREEMPT SMP ARM
[ 1704.877765] Modules linked in: evdev i2c_bcm2708 uio_pdrv_genirq uio
[ 1704.877774] CPU: 2 PID: 3656 Comm: stress-ng-fstat Not tainted 3.19.1-12-generic-bcm2709 #12-Ubuntu
[ 1704.877777] Hardware name: BCM2709
[ 1704.877783] task: b8ab9b00 ti: b7e68000 task.ti: b7e68000
[ 1704.877798] PC is at __down_interruptible+0x50/0xec
[ 1704.877806] LR is at down_interruptible+0x5c/0x68
[ 1704.877813] pc : [<80630ee8>] lr : [<800704b0>] psr: 60080093
sp : b7e69e50 ip : b7e69e88 fp : b7e69e84
[ 1704.877817] r10: b88123c8 r9 : 00000010 r8 : 00000001
[ 1704.877822] r7 : b8ab9b00 r6 : 7fffffff r5 : 80a1cc34 r4 : 80a1cc34
[ 1704.877826] r3 : b7e69e50 r2 : 00000000 r1 : 00000000 r0 : 80a1cc34
[ 1704.877833] Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment user
[ 1704.877838] Control: 10c5387d Table: 3899c06a DAC: 00000015
[ 1704.877843] Process do-oops (pid: 3656, stack limit = 0xb7e68238)
[ 1704.877848] Stack: (0xb7e69e50 to 0xb7e6a000)
[ 1704.877856] 9e40: 80a1cc3c 00000000 00000010 b88123c8
[ 1704.877865] 9e60: b7e69e84 80a1cc34 fff9fee9 ffffffff b7e68000 00000009 b7e69ea4 b7e69e88
[ 1704.877874] 9e80: 800704b0 80630ea4 fff9fee9 60080013 80a1cc28 fff9fee9 b7e69edc b7e69ea8
[ 1704.877884] 9ea0: 8040f558 80070460 fff9fee9 ffffffff 00000000 00000000 00000009 80a1cb7c
[ 1704.877893] 9ec0: 00000000 80a1cb7c 00000000 00000010 b7e69ef4 b7e69ee0 803e1ba4 8040f514
[ 1704.877902] 9ee0: 00000e48 80a1cb7c b7e69f14 b7e69ef8 803e1c9c 803e1b74 b88123c0 b92acb18
[ 1704.877911] 9f00: b8812790 b8d815d8 b7e69f24 b7e69f18 803e2250 803e1bc8 b7e69f5c b7e69f28
[ 1704.877921] 9f20: 80167bac 803e222c 00000000 00000000 b7e69f54 b8ab9ffc 00000000 8098c794
[ 1704.877930] 9f40: b8ab9b00 8000efc4 b7e68000 00000000 b7e69f6c b7e69f60 80167d6c 80167b28
[ 1704.877939] 9f60: b7e69f8c b7e69f70 80047d38 80167d60 b7e68000 b7e68010 8000efc4 b7e69fb0
[ 1704.877949] 9f80: b7e69fac b7e69f90 80012820 80047c84 01155490 011549a8 00000001 00000006
[ 1704.877957] 9fa0: 00000000 b7e69fb0 8000ee5c 80012790 00000000 353d8c0f 7efc4308 00000000
[ 1704.877966] 9fc0: 01155490 011549a8 00000001 00000006 00000000 00000000 76cf3ba0 00000003
[ 1704.877975] 9fe0: 00000000 7efc42e4 0002272f 76e2ed66 60080030 00000003 00000000 00000000
[ 1704.877998] [<80630ee8>] (__down_interruptible) from [<800704b0>] (down_interruptible+0x5c/0x68)
[ 1704.878015] [<800704b0>] (down_interruptible) from [<8040f558>] (vchiu_queue_push+0x50/0xd8)
[ 1704.878032] [<8040f558>] (vchiu_queue_push) from [<803e1ba4>] (send_worker_msg+0x3c/0x54)
[ 1704.878045] [<803e1ba4>] (send_worker_msg) from [<803e1c9c>] (vc_cma_set_reserve+0xe0/0x1c4)
[ 1704.878057] [<803e1c9c>] (vc_cma_set_reserve) from [<803e2250>] (vc_cma_release+0x30/0x38)
[ 1704.878069] [<803e2250>] (vc_cma_release) from [<80167bac>] (__fput+0x90/0x1e0)
[ 1704.878082] [<80167bac>] (__fput) from [<80167d6c>] (____fput+0x18/0x1c)
[ 1704.878094] [<80167d6c>] (____fput) from [<80047d38>] (task_work_run+0xc0/0xf8)
[ 1704.878109] [<80047d38>] (task_work_run) from [<80012820>] (do_work_pending+0x9c/0xc4)
[ 1704.878123] [<80012820>] (do_work_pending) from [<8000ee5c>] (work_pending+0xc/0x20)
[ 1704.878133] Code: e50b1034 e3a01000 e50b2030 e580300c (e5823000)

..the fix is to ensure that we have actually initialized the queue before we attempt
to push any items onto it. This occurs if we do an open() followed by a close() without
any activity in between.

Signed-off-by: Colin Ian King <colin.king@canonical.com>

vchiq_arm: Sort out the vmalloc case

See: https://github.com/raspberrypi/linux/issues/1055

vchiq: hack: Add include depecated dma include file

[gregkh] added dependancy on CONFIG_BROKEN to make things sane for now.

Cc: Eric Anholt <eric@anholt.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>