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author | Linus Torvalds <torvalds@linux-foundation.org> | 2018-08-23 13:52:46 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-08-23 13:52:46 -0700 |
commit | f3ea496213819c80ce9c49a9b65f9261da713d11 (patch) | |
tree | 1c8fad9c5c609504c2916ad3844494093f89f8f1 /Documentation/networking | |
parent | 9e259f9352d52053058a234f7c062c4e4f56dc85 (diff) | |
parent | 29ed45fff05899f6f39d05fe1c32b1bc51f8926b (diff) | |
download | lwn-f3ea496213819c80ce9c49a9b65f9261da713d11.tar.gz lwn-f3ea496213819c80ce9c49a9b65f9261da713d11.zip |
Merge tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC driver updates from Olof Johansson:
"Some of the larger changes this merge window:
- Removal of drivers for Exynos5440, a Samsung SoC that never saw
widespread use.
- Uniphier support for USB3 and SPI reset handling
- Syste control and SRAM drivers and bindings for Allwinner platforms
- Qualcomm AOSS (Always-on subsystem) reset controller drivers
- Raspberry Pi hwmon driver for voltage
- Mediatek pwrap (pmic) support for MT6797 SoC"
* tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (52 commits)
drivers/firmware: psci_checker: stash and use topology_core_cpumask for hotplug tests
soc: fsl: cleanup Kconfig menu
soc: fsl: dpio: Convert DPIO documentation to .rst
staging: fsl-mc: Remove remaining files
staging: fsl-mc: Move DPIO from staging to drivers/soc/fsl
staging: fsl-dpaa2: eth: move generic FD defines to DPIO
soc: fsl: qe: gpio: Add qe_gpio_set_multiple
usb: host: exynos: Remove support for Exynos5440
clk: samsung: Remove support for Exynos5440
soc: sunxi: Add the A13, A23 and H3 system control compatibles
reset: uniphier: add reset control support for SPI
cpufreq: exynos: Remove support for Exynos5440
ata: ahci-platform: Remove support for Exynos5440
soc: imx6qp: Use GENPD_FLAG_ALWAYS_ON for PU errata
soc: mediatek: pwrap: add mt6351 driver for mt6797 SoCs
soc: mediatek: pwrap: add pwrap driver for mt6797 SoCs
soc: mediatek: pwrap: fix cipher init setting error
dt-bindings: pwrap: mediatek: add pwrap support for MT6797
reset: uniphier: add USB3 core reset control
dt-bindings: reset: uniphier: add USB3 core reset support
...
Diffstat (limited to 'Documentation/networking')
-rw-r--r-- | Documentation/networking/dpaa2/dpio-driver.rst | 158 | ||||
-rw-r--r-- | Documentation/networking/dpaa2/index.rst | 1 |
2 files changed, 159 insertions, 0 deletions
diff --git a/Documentation/networking/dpaa2/dpio-driver.rst b/Documentation/networking/dpaa2/dpio-driver.rst new file mode 100644 index 000000000000..13588104161b --- /dev/null +++ b/Documentation/networking/dpaa2/dpio-driver.rst @@ -0,0 +1,158 @@ +.. include:: <isonum.txt> + +DPAA2 DPIO (Data Path I/O) Overview +=================================== + +:Copyright: |copy| 2016-2018 NXP + +This document provides an overview of the Freescale DPAA2 DPIO +drivers + +Introduction +============ + +A DPAA2 DPIO (Data Path I/O) is a hardware object that provides +interfaces to enqueue and dequeue frames to/from network interfaces +and other accelerators. A DPIO also provides hardware buffer +pool management for network interfaces. + +This document provides an overview the Linux DPIO driver, its +subcomponents, and its APIs. + +See Documentation/networking/dpaa2/overview.rst for a general overview of DPAA2 +and the general DPAA2 driver architecture in Linux. + +Driver Overview +--------------- + +The DPIO driver is bound to DPIO objects discovered on the fsl-mc bus and +provides services that: + A) allow other drivers, such as the Ethernet driver, to enqueue and dequeue + frames for their respective objects + B) allow drivers to register callbacks for data availability notifications + when data becomes available on a queue or channel + C) allow drivers to manage hardware buffer pools + +The Linux DPIO driver consists of 3 primary components-- + DPIO object driver-- fsl-mc driver that manages the DPIO object + + DPIO service-- provides APIs to other Linux drivers for services + + QBman portal interface-- sends portal commands, gets responses +:: + + fsl-mc other + bus drivers + | | + +---+----+ +------+-----+ + |DPIO obj| |DPIO service| + | driver |---| (DPIO) | + +--------+ +------+-----+ + | + +------+-----+ + | QBman | + | portal i/f | + +------------+ + | + hardware + + +The diagram below shows how the DPIO driver components fit with the other +DPAA2 Linux driver components:: + +------------+ + | OS Network | + | Stack | + +------------+ +------------+ + | Allocator |. . . . . . . | Ethernet | + |(DPMCP,DPBP)| | (DPNI) | + +-.----------+ +---+---+----+ + . . ^ | + . . <data avail, | |<enqueue, + . . tx confirm> | | dequeue> + +-------------+ . | | + | DPRC driver | . +--------+ +------------+ + | (DPRC) | . . |DPIO obj| |DPIO service| + +----------+--+ | driver |-| (DPIO) | + | +--------+ +------+-----+ + |<dev add/remove> +------|-----+ + | | QBman | + +----+--------------+ | portal i/f | + | MC-bus driver | +------------+ + | | | + | /soc/fsl-mc | | + +-------------------+ | + | + =========================================|=========|======================== + +-+--DPIO---|-----------+ + | | | + | QBman Portal | + +-----------------------+ + + ============================================================================ + + +DPIO Object Driver (dpio-driver.c) +---------------------------------- + + The dpio-driver component registers with the fsl-mc bus to handle objects of + type "dpio". The implementation of probe() handles basic initialization + of the DPIO including mapping of the DPIO regions (the QBman SW portal) + and initializing interrupts and registering irq handlers. The dpio-driver + registers the probed DPIO with dpio-service. + +DPIO service (dpio-service.c, dpaa2-io.h) +------------------------------------------ + + The dpio service component provides queuing, notification, and buffers + management services to DPAA2 drivers, such as the Ethernet driver. A system + will typically allocate 1 DPIO object per CPU to allow queuing operations + to happen simultaneously across all CPUs. + + Notification handling + dpaa2_io_service_register() + + dpaa2_io_service_deregister() + + dpaa2_io_service_rearm() + + Queuing + dpaa2_io_service_pull_fq() + + dpaa2_io_service_pull_channel() + + dpaa2_io_service_enqueue_fq() + + dpaa2_io_service_enqueue_qd() + + dpaa2_io_store_create() + + dpaa2_io_store_destroy() + + dpaa2_io_store_next() + + Buffer pool management + dpaa2_io_service_release() + + dpaa2_io_service_acquire() + +QBman portal interface (qbman-portal.c) +--------------------------------------- + + The qbman-portal component provides APIs to do the low level hardware + bit twiddling for operations such as: + -initializing Qman software portals + + -building and sending portal commands + + -portal interrupt configuration and processing + + The qbman-portal APIs are not public to other drivers, and are + only used by dpio-service. + +Other (dpaa2-fd.h, dpaa2-global.h) +---------------------------------- + + Frame descriptor and scatter-gather definitions and the APIs used to + manipulate them are defined in dpaa2-fd.h. + + Dequeue result struct and parsing APIs are defined in dpaa2-global.h. diff --git a/Documentation/networking/dpaa2/index.rst b/Documentation/networking/dpaa2/index.rst index 4c6586c87969..10bea113a7bc 100644 --- a/Documentation/networking/dpaa2/index.rst +++ b/Documentation/networking/dpaa2/index.rst @@ -6,3 +6,4 @@ DPAA2 Documentation :maxdepth: 1 overview + dpio-driver |