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>
Alex Elder