linux-toradex.git/include/linux/firmware.h, branch v4.11-rc3

firmware: support loading into a pre-allocated buffer

2016-08-02T23:35:10+00:00

Some systems are memory constrained but they need to load very large
firmwares.  The firmware subsystem allows drivers to request this
firmware be loaded from the filesystem, but this requires that the
entire firmware be loaded into kernel memory first before it's provided
to the driver.  This can lead to a situation where we map the firmware
twice, once to load the firmware into kernel memory and once to copy the
firmware into the final resting place.

This creates needless memory pressure and delays loading because we have
to copy from kernel memory to somewhere else.  Let's add a
request_firmware_into_buf() API that allows drivers to request firmware
be loaded directly into a pre-allocated buffer.  This skips the
intermediate step of allocating a buffer in kernel memory to hold the
firmware image while it's read from the filesystem.  It also requires
that drivers know how much memory they'll require before requesting the
firmware and negates any benefits of firmware caching because the
firmware layer doesn't manage the buffer lifetime.

For a 16MB buffer, about half the time is spent performing a memcpy from
the buffer to the final resting place.  I see loading times go from
0.081171 seconds to 0.047696 seconds after applying this patch.  Plus
the vmalloc pressure is reduced.

This is based on a patch from Vikram Mulukutla on codeaurora.org:
  https://www.codeaurora.org/cgit/quic/la/kernel/msm-3.18/commit/drivers/base/firmware_class.c?h=rel/msm-3.18&id=0a328c5f6cd999f5c591f172216835636f39bcb5

Link: http://lkml.kernel.org/r/20160607164741.31849-4-stephen.boyd@linaro.org
Signed-off-by: Stephen Boyd 
Cc: Mimi Zohar 
Cc: Vikram Mulukutla 
Cc: Mark Brown 
Cc: Ming Lei 
Cc: Greg Kroah-Hartman 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

firmware loader: inform direct failure when udev loader is disabled

2014-07-08T22:28:16+00:00

Now that the udev firmware loader is optional request_firmware()
will not provide any information on the kernel ring buffer if
direct firmware loading failed and udev firmware loading is disabled.
If no information is needed request_firmware_direct() should be used
for optional firmware, at which point drivers can take on the onus
over informing of any failures, if udev firmware loading is disabled
though we should at the very least provide some sort of information
as when the udev loader was enabled by default back in the days.

With this change with a simple firmware load test module [0]:

Example output without FW_LOADER_USER_HELPER_FALLBACK

platform fake-dev.0: Direct firmware load for fake.bin failed
with error -2

Example with FW_LOADER_USER_HELPER_FALLBACK

platform fake-dev.0: Direct firmware load for fake.bin failed with error -2
platform fake-dev.0: Falling back to user helper

Without this change without FW_LOADER_USER_HELPER_FALLBACK we
get no output logged upon failure.

Cc: Tom Gundersen 
Cc: Ming Lei 
Cc: Abhay Salunke 
Cc: Stefan Roese 
Cc: Arnd Bergmann 
Cc: Kay Sievers 
Signed-off-by: Luis R. Rodriguez 
Reviewed-by: Takashi Iwai 
Signed-off-by: Greg Kroah-Hartman

firmware loader: allow disabling of udev as firmware loader

2014-07-08T22:24:39+00:00

[The patch was originally proposed by Tom Gundersen, and rewritten
 afterwards by me; most of changelogs below borrowed from Tom's
 original patch -- tiwai]

Currently (at least) the dell-rbu driver selects FW_LOADER_USER_HELPER,
which means that distros can't really stop loading firmware through
udev without breaking other users (though some have).

Ideally we would remove/disable the udev firmware helper in both the
kernel and in udev, but if we were to disable it in udev and not the
kernel, the result would be (seemingly) hung kernels as no one would
be around to cancel firmware requests.

This patch allows udev firmware loading to be disabled while still
allowing non-udev firmware loading, as done by the dell-rbu driver, to
continue working. This is achieved by only using the fallback
mechanism when the uevent is suppressed.

The patch renames the user-selectable Kconfig from FW_LOADER_USER_HELPER
to FW_LOADER_USER_HELPER_FALLBACK, and the former is reverse-selected
by the latter or the drivers that need userhelper like dell-rbu.

Also, the "default y" is removed together with this change, since it's
been deprecated in udev upstream, thus rather better to disable it
nowadays.

Tested with
    FW_LOADER_USER_HELPER=n
    LATTICE_ECP3_CONFIG=y
    DELL_RBU=y
and udev without the firmware loading support, but I don't have the
hardware to test the lattice/dell drivers, so additional testing would
be appreciated.

Reviewed-by: Tom Gundersen 
Cc: Ming Lei 
Cc: Abhay Salunke 
Cc: Stefan Roese 
Cc: Arnd Bergmann 
Cc: Kay Sievers 
Tested-by: Balaji Singh 
Signed-off-by: Takashi Iwai 
Signed-off-by: Greg Kroah-Hartman

firmware: Introduce request_firmware_direct()

2013-12-09T02:22:32+00:00

When CONFIG_FW_LOADER_USER_HELPER is set, request_firmware() falls
back to the usermode helper for loading via udev when the direct
loading fails.  But the recent udev takes way too long timeout (60
seconds) for non-existing firmware.  This is unacceptable for the
drivers like microcode loader where they load firmwares optionally,
i.e. it's no error even if no requested file exists.

This patch provides a new helper function, request_firmware_direct().
It behaves as same as request_firmware() except for that it doesn't
fall back to usermode helper but returns an error immediately if the
f/w can't be loaded directly in kernel.

Without CONFIG_FW_LOADER_USER_HELPER=y, request_firmware_direct() is
just an alias of request_firmware(), due to obvious reason.

Tested-by: Prarit Bhargava 
Acked-by: Ming Lei 
Acked-by: Borislav Petkov 
Signed-off-by: Takashi Iwai 
Signed-off-by: Greg Kroah-Hartman

firmware loader: don't export cache_firmware and uncache_firmware

2013-06-06T19:41:57+00:00

Looks no driver has the explict requirement for the two exported
API, just don't export them anymore.

Signed-off-by: Ming Lei 
Signed-off-by: Greg Kroah-Hartman

firmware loader: introduce cache_firmware and uncache_firmware

2012-08-16T20:24:21+00:00

This patches introduce two kernel APIs of cache_firmware and
uncache_firmware, both of which take the firmware file name
as the only parameter.

So any drivers can call cache_firmware to cache the specified
firmware file into kernel memory, and can use the cached firmware
in situations which can't request firmware from user space.

Signed-off-by: Ming Lei 
Cc: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

firmware loader: always let firmware_buf own the pages buffer

2012-08-16T20:22:45+00:00

This patch always let firmware_buf own the pages buffer allocated
inside firmware_data_write, and add all instances of firmware_buf
into the firmware cache global list. Also introduce one private field
in 'struct firmware', so release_firmware will see the instance of
firmware_buf associated with the current firmware instance, then just
'free' the instance of firmware_buf.

The firmware_buf instance represents one pages buffer for one
firmware image, so lots of firmware loading requests can share
the same firmware_buf instance if they request the same firmware
image file.

This patch will make implementation of the following cache_firmware/
uncache_firmware very easy and simple.

In fact, the patch improves request_formware/release_firmware:

        - only request userspace to write firmware image once if
	several devices share one same firmware image and its drivers
	call request_firmware concurrently.

Signed-off-by: Ming Lei 
Cc: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

include: replace linux/module.h with "struct module" wherever possible

2011-10-31T23:32:32+00:00

The  pretty much brings in the kitchen sink along
with it, so it should be avoided wherever reasonably possible in
terms of being included from other commonly used 
files, as it results in a measureable increase on compile times.

The worst culprit was probably device.h since it is used everywhere.
This file also had an implicit dependency/usage of mutex.h which was
masked by module.h, and is also fixed here at the same time.

There are over a dozen other headers that simply declare the
struct instead of pulling in the whole file, so follow their lead
and simply make it a few more.

Most of the implicit dependencies on module.h being present by
these headers pulling it in have been now weeded out, so we can
finally make this change with hopefully minimal breakage.

Signed-off-by: Paul Gortmaker

firmware_classs: change val uevent's type to bool

2011-02-03T23:39:17+00:00

Some place in firmware_class.c using "int uevent" define, but others use "bool
uevent".
This patch replace all int uevent define to bool.

Signed-off-by: Bob Liu 
Acked-by: Dmitry Torokhov 
Signed-off-by: Greg Kroah-Hartman

firmware_class: fix memory leak - free allocated pages

2010-05-21T16:37:28+00:00

fix memory leak introduced by the patch 6e03a201bbe:
firmware: speed up request_firmware()

1. vfree won't release pages there were allocated explicitly and mapped
using vmap. The memory has to be vunmap-ed and the pages needs
to be freed explicitly

2. page array is moved into the 'struct
firmware' so that we can free it from release_firmware()
and not only in fw_dev_release()

The fix doesn't break the firmware load speed.

Cc: Johannes Berg 
Cc: Ming Lei 
Cc: Catalin Marinas 
Singed-off-by: Kay Sievers 
Signed-off-by: David Woodhouse 
Signed-off-by: Tomas Winkler 
Signed-off-by: Greg Kroah-Hartman