Print certain name string instead of hard-coded "memory" for dev_err
output, which would be more accurate and helpful for debugging.
Signed-off-by: Wang Wenhu <wenhu.wang@vivo.com>
Cc: Alex Elder <elder@kernel.org>
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The MSCC bug fix in 'net' had to be slightly adjusted because the
register accesses are done slightly differently in net-next.
Signed-off-by: David S. Miller <davem@davemloft.net>
In gsi_channel_start() there is harmless-looking comment "Clear the
channel's event ring interrupt in case it's pending". The intent
was to avoid getting spurious interrupts when first bringing up a
channel.
However we now use channel stop/start to implement suspend and
resume, and an interrupt pending at the time we resume is actually
something we don't want to ignore.
The very first time we bring up the channel we do not expect an
interrupt to be pending, and even if it were, the effect would
simply be to schedule NAPI on that channel, which would find nothing
to do, which is not a problem.
Stop clearing any pending IEOB interrupt in gsi_channel_start().
That leaves one caller of the trivial function gsi_isr_ieob_clear().
Get rid of that function and just open-code it in gsi_isr_ieob()
instead.
This fixes a problem where suspend/resume IPA v4.2 would get stuck
when resuming after a suspend.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use the suspend and resume callbacks rather than suspend_noirq and
resume_noirq. With IPA v4.2, we use the CHANNEL_STOP command to
implement a suspend, and without interrupts enabled, that command
won't complete.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The iteration count value used in gsi_channel_poll() is intended to
limit poll iterations to the budget supplied as an argument. But
it's never updated.
Fix this bug by incrementing the count each time through the loop.
Reported-by: Sharath Chandra Vurukala <sharathv@codeaurora.com>
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move the bpf verifier trace check into the new switch statement in
HEAD.
Resolve the overlapping changes in hinic, where bug fixes overlap
the addition of VF support.
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove the duplicate "mutex", and change "Motex" to "Mutex". Also I
recommend it's easier for understanding to make the "ready-interrupt"
a bundle for it is a parallel description as "shutdown" which is appended
after the slash.
Signed-off-by: Wang Wenhu <wenhu.wang@vivo.com>
Cc: Alex Elder <elder@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
One part of recovering from a modem crash is performing a "tag
sequence" of several IPA immediate commands, to clear the hardware
pipeline. The sequence ends with a data transfer request on the
command endpoint (which is not otherwise done). Unfortunately,
attempting to do the data transfer led to a hang, so that request
plus two other commands were commented out.
The previous commit fixes the bug that was causing that hang. And
with that bug fixed we can properly issue the tag sequence when the
modem crashes, to return the hardware to a known state.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
When a command gets added to a transaction for the AP->command
channel we set the DMA address of its scatterlist entry, but not
its DMA length. Fix this bug.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
When building arm64 allyesconfig:
drivers/net/ipa/ipa_endpoint.c: In function 'ipa_endpoint_stop_rx_dma':
drivers/net/ipa/ipa_endpoint.c:1274:13: error: 'IPA_ENDPOINT_STOP_RX_SIZE' undeclared (first use in this function)
drivers/net/ipa/ipa_endpoint.c:1274:13: note: each undeclared identifier is reported only once for each function it appears in
drivers/net/ipa/ipa_endpoint.c:1289:2: error: implicit declaration of function 'ipa_cmd_dma_task_32b_addr_add' [-Werror=implicit-function-declaration]
drivers/net/ipa/ipa_endpoint.c:1291:45: error: 'ENDPOINT_STOP_DMA_TIMEOUT' undeclared (first use in this function)
drivers/net/ipa/ipa_endpoint.c: In function 'ipa_endpoint_stop':
drivers/net/ipa/ipa_endpoint.c:1309:16: error: 'IPA_ENDPOINT_STOP_RX_RETRIES' undeclared (first use in this function)
These functions were removed in a series, merged in as
commit 33395f4a5c ("Merge branch 'net-ipa-kill-endpoint-stop-workaround'").
Remove them again so that the build works properly.
Fixes: 3793faad7b ("Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net")
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
A recent commit removed the only use of ipa_cmd_dma_task_32b_addr_add().
This function (and the IPA immediate command it implements) is no
longer needed, so get rid of it, along with all of the definitions
associated with it. Isolate its removal in a commit so it can be
easily added back again if needed.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The previous commit made ipa_endpoint_stop() be a trivial wrapper
around gsi_channel_stop(). Since it no longer does anything
special, just open-code it in the three places it's used.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The only reason ipa_endpoint_stop() had a retry loop was that the
just-removed workaround required an IPA DMA command to occur between
attempts. The gsi_channel_stop() call that implements the stop does
its own retry loop, to cover a channel's transition from started to
stop-in-progress to stopped state.
Get rid of the unnecessary retry loop in ipa_endpoint_stop().
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
In ipa_endpoint_stop(), a workaround is used for IPA version 3.5.1
where a 1-byte DMA request is issued between GSI channel stop
retries.
It turns out that this workaround is only required for IPA versions
3.1 and 3.2, and we don't support those. So remove the call to
ipa_endpoint_stop_rx_dma() in that function. That leaves that
function unused, so get rid of it.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
In ipa_endpoint_stop(), for TX endpoints we set the number of retries
to 0. When we break out of the loop, retries being 0 means we return
EIO rather than the value of ret (which should be 0).
Fix this by using a non-zero retry count for both RX and TX
channels, and just break out of the loop after calling
gsi_channel_stop() for TX channels. This way only RX channels
will retry, and the retry count will be non-zero at the end
for TX channels (so the proper value gets returned).
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit 713b6ebb4c)
Signed-off-by: David S. Miller <davem@davemloft.net>
A "delay mode" feature was put in place to work around a problem
that was observed during development of the upstream IPA driver. It
used TX endpoint "delay mode" in order to prevent transmitting
packets toward the modem before it was ready.
A race condition that would explain the problem has long since been
fixed, and we have concluded that the "delay mode" feature is no
longer required. So get rid of it.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Create a new helper function that encapsulates enabling or disabling
suspend on an RX endpoint. It returns the previous state of the
endpoint (true means suspend mode was enabled).
Create another function that handles enabling or disabling delay mode
on a TX endpoint. Delay mode does not work correctly on IPA version
4.2, so we don't currently use it (and shouldn't).
We only set delay mode in one case, and although we don't expect an
endpoint to already be in delay mode, it doesn't really matter if it
was. So the delay function doesn't return a value.
Stop issuing warnings if the previous suspend or delay mode state
differs from what is expected.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change ipa_endpoint_init_ctrl() so it returns the previous state
(whether suspend or delay mode was enabled) rather than indicating
whether the request caused a change in state. This makes it easier
to understand what's happening where called.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
In gsi_channel_reset(), RX channels are subjected to two consecutive
CHANNEL_RESET commands. This workaround should only be used for IPA
version 3.5.1, and for newer hardware "can lead to unwanted behavior."
Only issue the second CHANNEL_RESET command for legacy hardware.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
In several places, a Boolean flag is used in the GSI code to
indicate whether the "doorbell engine" should be enabled or not
when a channel is configured. This is basically done to abstract
this property from the IPA version; the GSI code doesn't otherwise
"know" what the IPA hardware version is. The doorbell engine is
enabled only for IPA v3.5.1, not for IPA v4.0 and later.
The next patch makes another change that affects behavior during
channel reset (which also involves programming the channel). It
also distinguishes IPA v3.5.1 hardware from newer hardware.
Rather than creating another flag whose value matches the "db_enable"
value, just rename "db_enable" to be "legacy" so it can be used to
signal more than just the special doorbell handling.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Arrange to use an item from SMEM memory for IPA. SMEM item number
497 is designated to be used by the IPA. Specify the item ID and
size of the region in platform configuration data. Allocate and get
a pointer to this region from ipa_mem_init(). The memory must be
mapped for access through an SMMU.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Define a region of IMEM memory available for use by IPA in the
platform configuration data. Initialize it from ipa_mem_init().
The memory must be mapped for access through an SMMU.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The ipa_mem_data structure type was never actually used. Instead,
the IPA memory regions were defined using the ipa_mem structure.
Redefine struct ipa_mem_data so it encapsulates the array of IPA-local
memory region descriptors along with the count of entries in that
array. Pass just an ipa_mem structure pointer to ipa_mem_init().
Rename the ipa_mem_data[] array ipa_mem_local_data[] to emphasize
that the memory regions it defines are IPA-local memory.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
It is possible for a GSI channel's state to be changed as a result
of an action by a different execution environment. Specifically,
the modem is able to issue a GSI generic command that causes a state
change on a GSI channel associated with the AP.
A channel's state only needs to be known when a channel is allocated
or deallocaed, started or stopped, or reset. So there is little
value in caching the state anyway.
Stop recording a copy of the channel's last known state, and instead
fetch the true state from hardware whenever it's needed. In such
cases, *do* record the state in a local variable, in case an error
message reports it (so the value reported is the value seen).
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pass a channel pointer rather than a GSI pointer and channel ID to
gsi_channel_state().
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Zero the result code stored in a field of the scratch 0 register
before issuing a generic EE command. This just guarantees that
the value we read later was actually written as a result of the
command.
Also add the definitions of two more possible result codes that can
be returned when issuing flow control enable or disable commands:
INCORRECT_CHANNEL_STATE: - channel must be in started state
INCORRECT_DIRECTION - flow control is only valid for TX channels
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
An error message about limiting the number of TREs used prints the
wrong value. Fix this bug.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
In ipa_endpoint_stop(), for TX endpoints we set the number of retries
to 0. When we break out of the loop, retries being 0 means we return
EIO rather than the value of ret (which should be 0).
Fix this by using a non-zero retry count for both RX and TX
channels, and just break out of the loop after calling
gsi_channel_stop() for TX channels. This way only RX channels
will retry, and the retry count will be non-zero at the end
for TX channels (so the proper value gets returned).
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Message logged by 'dev_xxx()' or 'pr_xxx()' should end with a '\n'.
Fixes: a646d6ec90 ("soc: qcom: ipa: modem and microcontroller")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Don't assume the receive buffer size is a power-of-2 number of pages.
Instead, define the receive buffer size independently, and then
compute the page order from that size when needed.
This fixes a build problem that arises when the ARM64_PAGE_SHIFT
config option is set to have a page size greater than 4KB. The
problem was identified by Linux Kernel Functional Testing.
The IPA code basically assumed the page size to be 4KB. A larger page
size caused the receive buffer size to become correspondingly larger
(32KB or 128KB for ARM64_16K_PAGES and ARM64_64K_PAGES, respectively).
The receive buffer size is used to compute an "aggregation byte limit"
value that gets programmed into the hardware, and the large page sizes
caused that limit value to be too big to fit in a 5 bit field. This
triggered a BUILD_BUG_ON() call in ipa_endpoint_validate_build().
This fix causes a lot of receive buffer memory to be wasted if
system is configured for page size greater than 4KB. But such a
misguided configuration will now build successfully.
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Alex Elder <elder@linaro.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove including <linux/version.h> that don't need it.
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove .owner field if calls are used which set it automatically
Generated by: scripts/coccinelle/api/platform_no_drv_owner.cocci
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Rearrange the config files for remoteproc and IPA to fix their
interdependencies.
First, have CONFIG_QCOM_Q6V5_MSS select QCOM_Q6V5_IPA_NOTIFY so the
notification code is built regardless of whether IPA needs it.
Next, represent QCOM_IPA as being dependent on QCOM_Q6V5_MSS rather
than setting its value to match QCOM_Q6V5_COMMON (which is selected
by QCOM_Q6V5_MSS).
Drop all dependencies from QCOM_Q6V5_IPA_NOTIFY. The notification
code will be built whenever QCOM_Q6V5_MSS is set, and it has no other
dependencies.
Signed-off-by: Alex Elder <elder@linaro.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
There is a spelling mistake in a dev_err message. Fix it.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add build and Kconfig support for the Qualcomm IPA driver.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch implements two forms of out-of-band communication between
the AP and modem.
- QMI is a mechanism that allows clients running on the AP
interact with services running on the modem (and vice-versa).
The AP IPA driver uses QMI to communicate with the corresponding
IPA driver resident on the modem, to agree on parameters used
with the IPA hardware and to ensure both sides are ready before
entering operational mode.
- SMP2P is a more primitive mechanism available for the modem and
AP to communicate with each other. It provides a means for either
the AP or modem to interrupt the other, and furthermore, to provide
32 bits worth of information. The IPA driver uses SMP2P to tell
the modem what the state of the IPA clock was in the event of a
crash. This allows the modem to safely access the IPA hardware
(or avoid doing so) when a crash occurs, for example, to access
information within the IPA hardware.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch includes code implementing the modem functionality.
There are several communication paths between the AP and modem,
separate from the main data path provided by IPA. SMP2P provides
primitive messaging and interrupt capability, and QMI allows more
complex out-of-band messaging to occur between entities on the AP
and modem. (SMP2P and QMI support are added by the next patch.)
Management of these (plus the network device implementing the data
path) is done by code within "ipa_modem.c".
Sort of unrelated, this patch also includes the code supporting the
microcontroller CPU present on the IPA. The microcontroller can be
used to implement special handling of packets, but at this time we
don't support that. Still, it is a component that needs to be
initialized, and in the event of a crash we need to do some
synchronization between the AP and the microcontroller.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
One TX endpoint (per EE) is used for issuing immediate commands to
the IPA. These commands request activites beyond simple data
transfers to be done by the IPA hardware. For example, the IPA is
able to manage routing packets among endpoints, and immediate commands
are used to configure tables used for that routing.
Immediate commands are built on top of GSI transactions. They are
different from normal transfers (in that they use a special endpoint,
and their "payload" is interpreted differently), so separate functions
are used to issue immediate command transactions.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch contains code implementing filter and routing tables for
the IPA. A filter table allows rules to be used for filtering
packets that depart the AP at an endpoint. A filter table entry
contains the address of a set of rules to apply for each endpoint
that supports filtering.
A routing table allows packets to be routed to an endpoint based
on packet metadata. It is also a table whose entries each contain
the address of a set of routing rules to apply.
Neither filtering nor routing is supported by the current driver.
All table entries refer to rules that mean "no filtering" and "no
routing."
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch includes the code implementing an IPA endpoint. This is
the primary abstraction implemented by the IPA. An endpoint is one
end of a network connection between two entities physically
connected to the IPA. Specifically, the AP and the modem implement
endpoints, and an (AP endpoint, modem endpoint) pair implements the
transfer of network data in one direction between the AP and modem.
Endpoints are built on top of GSI channels, but IPA endpoints
represent the higher-level functionality that the IPA provides.
Data can be sent through a GSI channel, but it is the IPA endpoint
that represents what is on the "other end" to receive that data.
Other functionality, including aggregation, checksum offload and
(at some future date) IP routing and filtering are all associated
with the IPA endpoint.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch implements GSI transactions. A GSI transaction is a
structure that represents a single request (consisting of one or
more TREs) sent to the GSI hardware. The last TRE in a transaction
includes a flag requesting that the GSI interrupt the AP to notify
that it has completed.
TREs are executed and completed strictly in order. For this reason,
the completion of a single TRE implies that all previous TREs (in
particular all of those "earlier" in a transaction) have completed.
Whenever there is a need to send a request (a set of TREs) to the
IPA, a GSI transaction is allocated, specifying the number of TREs
that will be required. Details of the request (e.g. transfer offsets
and length) are represented by in a Linux scatterlist array that is
incorporated in the transaction structure.
Once all commands (TREs) are added to a transaction it is committed.
When the hardware signals that the request has completed, a callback
function allows for cleanup or followup activity to be performed
before the transaction is freed.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch provides interface functions supplied by the IPA layer
that are called from the GSI layer. One function is called when a
GSI transaction has completed. The others allow the GSI layer to
inform the IPA layer when the hardware has been told it has new TREs
to execute, and when the hardware has indicated transactions have
completed.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch includes "gsi.c", which implements the generic software
interface (GSI) for IPA. The generic software interface abstracts
channels, which provide a means of transferring data either from the
AP to the IPA, or from the IPA to the AP. A ring buffer of "transfer
elements" (TREs) is used to describe data transfers to perform. The
AP writes a doorbell register associated with a channel to let it know
it has added new entries (for an AP->IPA channel) or has finished
processing entries (for an IPA->AP channel).
Each channel also has an event ring buffer, used by the IPA to
communicate information about events related to a channel (for
example, the completion of TREs). The IPA writes its own doorbell
register, which triggers an interrupt on the AP, to signal that
new event information has arrived.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The Generic Software Interface is a layer of the IPA driver that
abstracts the underlying hardware. The next patch includes the
main code for GSI (including some additional documentation). This
patch just includes three GSI header files.
- "gsi.h" is the top-level GSI header file. This structure is
is embedded within the IPA structure. The main abstraction
implemented by the GSI code is the channel, and this header
exposes several operations that can be performed on a GSI channel.
- "gsi_private.h" exposes some definitions that are intended to be
private, used only by the main GSI code and the GSI transaction
code (defined in an upcoming patch).
- Like "ipa_reg.h", "gsi_reg.h" defines the offsets of the 32-bit
registers used by the GSI layer, along with masks that define the
position and width of fields less than 32 bits located within
these registers.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch incorporates three source files (and their headers). They're
grouped into one patch mainly for the purpose of making the number and
size of patches in this series somewhat reasonable.
- "ipa_clock.c" and "ipa_clock.h" implement clocking for the IPA device.
The IPA has a single core clock managed by the common clock framework.
In addition, the IPA has three buses whose bandwidth is managed by the
Linux interconnect framework. At this time the core clock and all
three buses are either on or off; we don't yet do any more fine-grained
management than that. The core clock and interconnects are enabled
and disabled as a unit, using a unified clock-like abstraction,
ipa_clock_get()/ipa_clock_put().
- "ipa_interrupt.c" and "ipa_interrupt.h" implement IPA interrupts.
There are two hardware IRQs used by the IPA driver (the other is
the GSI interrupt, described in a separate patch). Several types
of interrupt are handled by the IPA IRQ handler; these are not part
of data/fast path.
- The IPA has a region of local memory that is accessible by the AP
(and modem). Within that region are areas with certain defined
purposes. "ipa_mem.c" and "ipa_mem.h" define those regions, and
implement their initialization.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch defines configuration data that is used to specify some
of the details of IPA hardware supported by the driver. It is built
as Device Tree match data, discovered at boot time. The driver
supports the Qualcomm SDM845 SoC. Data for the Qualcomm SC7180 is
also defined here, but it is not yet completely supported.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch includes three source files that represent some basic "main
program" code for the IPA driver. They are:
- "ipa.h" defines the top-level IPA structure which represents an IPA
device throughout the code.
- "ipa_main.c" contains the platform driver probe function, along with
some general code used during initialization.
- "ipa_reg.h" defines the offsets of the 32-bit registers used for the
IPA device, along with masks that define the position and width of
fields within these registers.
- "version.h" defines some symbolic IPA version numbers.
Each file includes some documentation that provides a little more
overview of how the code is organized and used.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
