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authorLinus Torvalds <torvalds@linux-foundation.org>2018-08-23 23:52:46 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2018-08-23 23:52:46 +0300
commitf3ea496213819c80ce9c49a9b65f9261da713d11 (patch)
tree1c8fad9c5c609504c2916ad3844494093f89f8f1 /Documentation/networking
parent9e259f9352d52053058a234f7c062c4e4f56dc85 (diff)
parent29ed45fff05899f6f39d05fe1c32b1bc51f8926b (diff)
downloadlinux-f3ea496213819c80ce9c49a9b65f9261da713d11.tar.xz
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.rst158
-rw-r--r--Documentation/networking/dpaa2/index.rst1
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