diff mbox series

[v9,17/17] Documentation: PCI: Add userguide for PCI endpoint NTB function

Message ID 20210104152909.22038-18-kishon@ti.com
State New
Headers show
Series Implement NTB Controller using multiple PCI EP | expand

Commit Message

Kishon Vijay Abraham I Jan. 4, 2021, 3:29 p.m. UTC 
Add documentation to help users use pci-epf-ntb function driver and
existing host side NTB infrastructure for NTB functionality.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
---
 Documentation/PCI/endpoint/index.rst         |   1 +
 Documentation/PCI/endpoint/pci-ntb-howto.rst | 160 +++++++++++++++++++
 2 files changed, 161 insertions(+)
 create mode 100644 Documentation/PCI/endpoint/pci-ntb-howto.rst

Comments

Bjorn Helgaas Jan. 19, 2021, 6:34 p.m. UTC | #1 
On Mon, Jan 04, 2021 at 08:59:09PM +0530, Kishon Vijay Abraham I wrote:
> Add documentation to help users use pci-epf-ntb function driver and
> existing host side NTB infrastructure for NTB functionality.
> 
> Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
> Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
> ---
>  Documentation/PCI/endpoint/index.rst         |   1 +
>  Documentation/PCI/endpoint/pci-ntb-howto.rst | 160 +++++++++++++++++++
>  2 files changed, 161 insertions(+)
>  create mode 100644 Documentation/PCI/endpoint/pci-ntb-howto.rst
> 
> diff --git a/Documentation/PCI/endpoint/index.rst b/Documentation/PCI/endpoint/index.rst
> index 9cb6e5f3c4d5..38ea1f604b6d 100644
> --- a/Documentation/PCI/endpoint/index.rst
> +++ b/Documentation/PCI/endpoint/index.rst
> @@ -12,6 +12,7 @@ PCI Endpoint Framework
>     pci-test-function
>     pci-test-howto
>     pci-ntb-function
> +   pci-ntb-howto
>  
>     function/binding/pci-test
>     function/binding/pci-ntb
> diff --git a/Documentation/PCI/endpoint/pci-ntb-howto.rst b/Documentation/PCI/endpoint/pci-ntb-howto.rst
> new file mode 100644
> index 000000000000..b6e1073c9a39
> --- /dev/null
> +++ b/Documentation/PCI/endpoint/pci-ntb-howto.rst
> @@ -0,0 +1,160 @@
> +.. SPDX-License-Identifier: GPL-2.0
> +
> +===================================================================
> +PCI Non-Transparent Bridge (NTB) Endpoint Function (EPF) User Guide
> +===================================================================
> +
> +:Author: Kishon Vijay Abraham I <kishon@ti.com>
> +
> +This document is a guide to help users use pci-epf-ntb function driver
> +and ntb_hw_epf host driver for NTB functionality. The list of steps to
> +be followed in the host side and EP side is given below. For the hardware
> +configuration and internals of NTB using configurable endpoints see
> +Documentation/PCI/endpoint/pci-ntb-function.rst
> +
> +Endpoint Device
> +===============
> +
> +Endpoint Controller Devices
> +---------------------------
> +
> +For implementing NTB functionality at least two endpoint controller devices
> +are required.
> +To find the list of endpoint controller devices in the system::

Is the above one paragraph or two?  Reflow or add blank line as
appropriate.
Kishon Vijay Abraham I Jan. 22, 2021, 2:08 p.m. UTC | #2 
Hi Bjorn,

On 20/01/21 12:04 am, Bjorn Helgaas wrote:
> On Mon, Jan 04, 2021 at 08:59:09PM +0530, Kishon Vijay Abraham I wrote:
>> Add documentation to help users use pci-epf-ntb function driver and
>> existing host side NTB infrastructure for NTB functionality.
>>
>> Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
>> Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
>> ---
>>  Documentation/PCI/endpoint/index.rst         |   1 +
>>  Documentation/PCI/endpoint/pci-ntb-howto.rst | 160 +++++++++++++++++++
>>  2 files changed, 161 insertions(+)
>>  create mode 100644 Documentation/PCI/endpoint/pci-ntb-howto.rst
>>
>> diff --git a/Documentation/PCI/endpoint/index.rst b/Documentation/PCI/endpoint/index.rst
>> index 9cb6e5f3c4d5..38ea1f604b6d 100644
>> --- a/Documentation/PCI/endpoint/index.rst
>> +++ b/Documentation/PCI/endpoint/index.rst
>> @@ -12,6 +12,7 @@ PCI Endpoint Framework
>>     pci-test-function
>>     pci-test-howto
>>     pci-ntb-function
>> +   pci-ntb-howto
>>  
>>     function/binding/pci-test
>>     function/binding/pci-ntb
>> diff --git a/Documentation/PCI/endpoint/pci-ntb-howto.rst b/Documentation/PCI/endpoint/pci-ntb-howto.rst
>> new file mode 100644
>> index 000000000000..b6e1073c9a39
>> --- /dev/null
>> +++ b/Documentation/PCI/endpoint/pci-ntb-howto.rst
>> @@ -0,0 +1,160 @@
>> +.. SPDX-License-Identifier: GPL-2.0
>> +
>> +===================================================================
>> +PCI Non-Transparent Bridge (NTB) Endpoint Function (EPF) User Guide
>> +===================================================================
>> +
>> +:Author: Kishon Vijay Abraham I <kishon@ti.com>
>> +
>> +This document is a guide to help users use pci-epf-ntb function driver
>> +and ntb_hw_epf host driver for NTB functionality. The list of steps to
>> +be followed in the host side and EP side is given below. For the hardware
>> +configuration and internals of NTB using configurable endpoints see
>> +Documentation/PCI/endpoint/pci-ntb-function.rst
>> +
>> +Endpoint Device
>> +===============
>> +
>> +Endpoint Controller Devices
>> +---------------------------
>> +
>> +For implementing NTB functionality at least two endpoint controller devices
>> +are required.
>> +To find the list of endpoint controller devices in the system::
> 
> Is the above one paragraph or two?  Reflow or add blank line as
> appropriate.

I'll add blank line above.

Thanks
Kishon
diff mbox series

Patch

diff --git a/Documentation/PCI/endpoint/index.rst b/Documentation/PCI/endpoint/index.rst
index 9cb6e5f3c4d5..38ea1f604b6d 100644
--- a/Documentation/PCI/endpoint/index.rst
+++ b/Documentation/PCI/endpoint/index.rst
@@ -12,6 +12,7 @@  PCI Endpoint Framework
    pci-test-function
    pci-test-howto
    pci-ntb-function
+   pci-ntb-howto
 
    function/binding/pci-test
    function/binding/pci-ntb
diff --git a/Documentation/PCI/endpoint/pci-ntb-howto.rst b/Documentation/PCI/endpoint/pci-ntb-howto.rst
new file mode 100644
index 000000000000..b6e1073c9a39
--- /dev/null
+++ b/Documentation/PCI/endpoint/pci-ntb-howto.rst
@@ -0,0 +1,160 @@ 
+.. SPDX-License-Identifier: GPL-2.0
+
+===================================================================
+PCI Non-Transparent Bridge (NTB) Endpoint Function (EPF) User Guide
+===================================================================
+
+:Author: Kishon Vijay Abraham I <kishon@ti.com>
+
+This document is a guide to help users use pci-epf-ntb function driver
+and ntb_hw_epf host driver for NTB functionality. The list of steps to
+be followed in the host side and EP side is given below. For the hardware
+configuration and internals of NTB using configurable endpoints see
+Documentation/PCI/endpoint/pci-ntb-function.rst
+
+Endpoint Device
+===============
+
+Endpoint Controller Devices
+---------------------------
+
+For implementing NTB functionality at least two endpoint controller devices
+are required.
+To find the list of endpoint controller devices in the system::
+
+        # ls /sys/class/pci_epc/
+          2900000.pcie-ep  2910000.pcie-ep
+
+If PCI_ENDPOINT_CONFIGFS is enabled::
+
+	# ls /sys/kernel/config/pci_ep/controllers
+	  2900000.pcie-ep  2910000.pcie-ep
+
+
+Endpoint Function Drivers
+-------------------------
+
+To find the list of endpoint function drivers in the system::
+
+	# ls /sys/bus/pci-epf/drivers
+	  pci_epf_ntb   pci_epf_ntb
+
+If PCI_ENDPOINT_CONFIGFS is enabled::
+
+	# ls /sys/kernel/config/pci_ep/functions
+	  pci_epf_ntb   pci_epf_ntb
+
+
+Creating pci-epf-ntb Device
+----------------------------
+
+PCI endpoint function device can be created using the configfs. To create
+pci-epf-ntb device, the following commands can be used::
+
+	# mount -t configfs none /sys/kernel/config
+	# cd /sys/kernel/config/pci_ep/
+	# mkdir functions/pci_epf_ntb/func1
+
+The "mkdir func1" above creates the pci-epf-ntb function device that will
+be probed by pci_epf_ntb driver.
+
+The PCI endpoint framework populates the directory with the following
+configurable fields::
+
+	# ls functions/pci_epf_ntb/func1
+          baseclass_code    deviceid          msi_interrupts    pci-epf-ntb.0
+          progif_code       secondary         subsys_id         vendorid
+          cache_line_size   interrupt_pin     msix_interrupts   primary
+          revid             subclass_code     subsys_vendor_id
+
+The PCI endpoint function driver populates these entries with default values
+when the device is bound to the driver. The pci-epf-ntb driver populates
+vendorid with 0xffff and interrupt_pin with 0x0001::
+
+	# cat functions/pci_epf_ntb/func1/vendorid
+	  0xffff
+	# cat functions/pci_epf_ntb/func1/interrupt_pin
+	  0x0001
+
+
+Configuring pci-epf-ntb Device
+-------------------------------
+
+The user can configure the pci-epf-ntb device using its configfs entry. In order
+to change the vendorid and the deviceid, the following
+commands can be used::
+
+	# echo 0x104c > functions/pci_epf_ntb/func1/vendorid
+	# echo 0xb00d > functions/pci_epf_ntb/func1/deviceid
+
+In order to configure NTB specific attributes, a new sub-directory to func1
+should be created::
+
+	# mkdir functions/pci_epf_ntb/func1/pci_epf_ntb.0/
+
+The NTB function driver will populate this directory with various attributes
+that can be configured by the user::
+
+	# ls functions/pci_epf_ntb/func1/pci_epf_ntb.0/
+          db_count    mw1         mw2         mw3         mw4         num_mws
+          spad_count
+
+A sample configuration for NTB function is given below::
+
+	# echo 4 > functions/pci_epf_ntb/func1/pci_epf_ntb.0/db_count
+	# echo 128 > functions/pci_epf_ntb/func1/pci_epf_ntb.0/spad_count
+	# echo 2 > functions/pci_epf_ntb/func1/pci_epf_ntb.0/num_mws
+	# echo 0x100000 > functions/pci_epf_ntb/func1/pci_epf_ntb.0/mw1
+	# echo 0x100000 > functions/pci_epf_ntb/func1/pci_epf_ntb.0/mw2
+
+Binding pci-epf-ntb Device to EP Controller
+--------------------------------------------
+
+NTB function device should be attached to two PCIe endpoint controllers
+connected to the two hosts. Use the 'primary' and 'secondary' entries
+inside NTB function device to attach one PCIe endpoint controller to
+primary interface and the other PCIe endpoint controller to the secondary
+interface. ::
+
+        # ln -s controllers/2900000.pcie-ep/ functions/pci-epf-ntb/func1/primary
+        # ln -s controllers/2910000.pcie-ep/ functions/pci-epf-ntb/func1/secondary
+
+Once the above step is completed, both the PCI endpoint controllers are ready to
+establish a link with the host.
+
+
+Start the Link
+--------------
+
+In order for the endpoint device to establish a link with the host, the _start_
+field should be populated with '1'. For NTB, both the PCIe endpoint controllers
+should establish link with the host::
+
+        #echo 1 > controllers/2900000.pcie-ep/start
+        #echo 1 > controllers/2910000.pcie-ep/start
+
+
+RootComplex Device
+==================
+
+lspci Output
+------------
+
+Note that the devices listed here correspond to the values populated in
+"Creating pci-epf-ntb Device" section above::
+
+        # lspci
+        0000:00:00.0 PCI bridge: Texas Instruments Device b00d
+        0000:01:00.0 RAM memory: Texas Instruments Device b00d
+
+
+Using ntb_hw_epf Device
+-----------------------
+
+The host side software follows the standard NTB software architecture in Linux.
+All the existing client side NTB utilities like NTB Transport Client and NTB
+Netdev, NTB Ping Pong Test Client and NTB Tool Test Client can be used with NTB
+function device.
+
+For more information on NTB see
+:doc:`Non-Transparent Bridge <../../driver-api/ntb>`