diff options
Diffstat (limited to 'Documentation/PCI')
| -rw-r--r-- | Documentation/PCI/00-INDEX | 10 | ||||
| -rw-r--r-- | Documentation/PCI/endpoint/function/binding/pci-test.txt | 17 | ||||
| -rw-r--r-- | Documentation/PCI/endpoint/pci-endpoint-cfs.txt | 105 | ||||
| -rw-r--r-- | Documentation/PCI/endpoint/pci-endpoint.txt | 215 | ||||
| -rw-r--r-- | Documentation/PCI/endpoint/pci-test-function.txt | 66 | ||||
| -rw-r--r-- | Documentation/PCI/endpoint/pci-test-howto.txt | 179 |
6 files changed, 592 insertions, 0 deletions
diff --git a/Documentation/PCI/00-INDEX b/Documentation/PCI/00-INDEX index 147231f1613e..00c9a90b6f38 100644 --- a/Documentation/PCI/00-INDEX +++ b/Documentation/PCI/00-INDEX @@ -12,3 +12,13 @@ pci.txt - info on the PCI subsystem for device driver authors pcieaer-howto.txt - the PCI Express Advanced Error Reporting Driver Guide HOWTO +endpoint/pci-endpoint.txt + - guide to add endpoint controller driver and endpoint function driver. +endpoint/pci-endpoint-cfs.txt + - guide to use configfs to configure the PCI endpoint function. +endpoint/pci-test-function.txt + - specification of *PCI test* function device. +endpoint/pci-test-howto.txt + - userguide for PCI endpoint test function. +endpoint/function/binding/ + - binding documentation for PCI endpoint function diff --git a/Documentation/PCI/endpoint/function/binding/pci-test.txt b/Documentation/PCI/endpoint/function/binding/pci-test.txt new file mode 100644 index 000000000000..3b68b955fb50 --- /dev/null +++ b/Documentation/PCI/endpoint/function/binding/pci-test.txt @@ -0,0 +1,17 @@ +PCI TEST ENDPOINT FUNCTION + +name: Should be "pci_epf_test" to bind to the pci_epf_test driver. + +Configurable Fields: +vendorid : should be 0x104c +deviceid : should be 0xb500 for DRA74x and 0xb501 for DRA72x +revid : don't care +progif_code : don't care +subclass_code : don't care +baseclass_code : should be 0xff +cache_line_size : don't care +subsys_vendor_id : don't care +subsys_id : don't care +interrupt_pin : Should be 1 - INTA, 2 - INTB, 3 - INTC, 4 -INTD +msi_interrupts : Should be 1 to 32 depending on the number of MSI interrupts + to test diff --git a/Documentation/PCI/endpoint/pci-endpoint-cfs.txt b/Documentation/PCI/endpoint/pci-endpoint-cfs.txt new file mode 100644 index 000000000000..d740f29960a4 --- /dev/null +++ b/Documentation/PCI/endpoint/pci-endpoint-cfs.txt @@ -0,0 +1,105 @@ + CONFIGURING PCI ENDPOINT USING CONFIGFS + Kishon Vijay Abraham I <kishon@ti.com> + +The PCI Endpoint Core exposes configfs entry (pci_ep) to configure the +PCI endpoint function and to bind the endpoint function +with the endpoint controller. (For introducing other mechanisms to +configure the PCI Endpoint Function refer to [1]). + +*) Mounting configfs + +The PCI Endpoint Core layer creates pci_ep directory in the mounted configfs +directory. configfs can be mounted using the following command. + + mount -t configfs none /sys/kernel/config + +*) Directory Structure + +The pci_ep configfs has two directories at its root: controllers and +functions. Every EPC device present in the system will have an entry in +the *controllers* directory and and every EPF driver present in the system +will have an entry in the *functions* directory. + +/sys/kernel/config/pci_ep/ + .. controllers/ + .. functions/ + +*) Creating EPF Device + +Every registered EPF driver will be listed in controllers directory. The +entries corresponding to EPF driver will be created by the EPF core. + +/sys/kernel/config/pci_ep/functions/ + .. <EPF Driver1>/ + ... <EPF Device 11>/ + ... <EPF Device 21>/ + .. <EPF Driver2>/ + ... <EPF Device 12>/ + ... <EPF Device 22>/ + +In order to create a <EPF device> of the type probed by <EPF Driver>, the +user has to create a directory inside <EPF DriverN>. + +Every <EPF device> directory consists of the following entries that can be +used to configure the standard configuration header of the endpoint function. +(These entries are created by the framework when any new <EPF Device> is +created) + + .. <EPF Driver1>/ + ... <EPF Device 11>/ + ... vendorid + ... deviceid + ... revid + ... progif_code + ... subclass_code + ... baseclass_code + ... cache_line_size + ... subsys_vendor_id + ... subsys_id + ... interrupt_pin + +*) EPC Device + +Every registered EPC device will be listed in controllers directory. The +entries corresponding to EPC device will be created by the EPC core. + +/sys/kernel/config/pci_ep/controllers/ + .. <EPC Device1>/ + ... <Symlink EPF Device11>/ + ... <Symlink EPF Device12>/ + ... start + .. <EPC Device2>/ + ... <Symlink EPF Device21>/ + ... <Symlink EPF Device22>/ + ... start + +The <EPC Device> directory will have a list of symbolic links to +<EPF Device>. These symbolic links should be created by the user to +represent the functions present in the endpoint device. + +The <EPC Device> directory will also have a *start* field. Once +"1" is written to this field, the endpoint device will be ready to +establish the link with the host. This is usually done after +all the EPF devices are created and linked with the EPC device. + + + | controllers/ + | <Directory: EPC name>/ + | <Symbolic Link: Function> + | start + | functions/ + | <Directory: EPF driver>/ + | <Directory: EPF device>/ + | vendorid + | deviceid + | revid + | progif_code + | subclass_code + | baseclass_code + | cache_line_size + | subsys_vendor_id + | subsys_id + | interrupt_pin + | function + +[1] -> Documentation/PCI/endpoint/pci-endpoint.txt diff --git a/Documentation/PCI/endpoint/pci-endpoint.txt b/Documentation/PCI/endpoint/pci-endpoint.txt new file mode 100644 index 000000000000..9b1d66829290 --- /dev/null +++ b/Documentation/PCI/endpoint/pci-endpoint.txt @@ -0,0 +1,215 @@ + PCI ENDPOINT FRAMEWORK + Kishon Vijay Abraham I <kishon@ti.com> + +This document is a guide to use the PCI Endpoint Framework in order to create +endpoint controller driver, endpoint function driver, and using configfs +interface to bind the function driver to the controller driver. + +1. Introduction + +Linux has a comprehensive PCI subsystem to support PCI controllers that +operates in Root Complex mode. The subsystem has capability to scan PCI bus, +assign memory resources and IRQ resources, load PCI driver (based on +vendor ID, device ID), support other services like hot-plug, power management, +advanced error reporting and virtual channels. + +However the PCI controller IP integrated in some SoCs is capable of operating +either in Root Complex mode or Endpoint mode. PCI Endpoint Framework will +add endpoint mode support in Linux. This will help to run Linux in an +EP system which can have a wide variety of use cases from testing or +validation, co-processor accelerator, etc. + +2. PCI Endpoint Core + +The PCI Endpoint Core layer comprises 3 components: the Endpoint Controller +library, the Endpoint Function library, and the configfs layer to bind the +endpoint function with the endpoint controller. + +2.1 PCI Endpoint Controller(EPC) Library + +The EPC library provides APIs to be used by the controller that can operate +in endpoint mode. It also provides APIs to be used by function driver/library +in order to implement a particular endpoint function. + +2.1.1 APIs for the PCI controller Driver + +This section lists the APIs that the PCI Endpoint core provides to be used +by the PCI controller driver. + +*) devm_pci_epc_create()/pci_epc_create() + + The PCI controller driver should implement the following ops: + * write_header: ops to populate configuration space header + * set_bar: ops to configure the BAR + * clear_bar: ops to reset the BAR + * alloc_addr_space: ops to allocate in PCI controller address space + * free_addr_space: ops to free the allocated address space + * raise_irq: ops to raise a legacy or MSI interrupt + * start: ops to start the PCI link + * stop: ops to stop the PCI link + + The PCI controller driver can then create a new EPC device by invoking + devm_pci_epc_create()/pci_epc_create(). + +*) devm_pci_epc_destroy()/pci_epc_destroy() + + The PCI controller driver can destroy the EPC device created by either + devm_pci_epc_create() or pci_epc_create() using devm_pci_epc_destroy() or + pci_epc_destroy(). + +*) pci_epc_linkup() + + In order to notify all the function devices that the EPC device to which + they are linked has established a link with the host, the PCI controller + driver should invoke pci_epc_linkup(). + +*) pci_epc_mem_init() + + Initialize the pci_epc_mem structure used for allocating EPC addr space. + +*) pci_epc_mem_exit() + + Cleanup the pci_epc_mem structure allocated during pci_epc_mem_init(). + +2.1.2 APIs for the PCI Endpoint Function Driver + +This section lists the APIs that the PCI Endpoint core provides to be used +by the PCI endpoint function driver. + +*) pci_epc_write_header() + + The PCI endpoint function driver should use pci_epc_write_header() to + write the standard configuration header to the endpoint controller. + +*) pci_epc_set_bar() + + The PCI endpoint function driver should use pci_epc_set_bar() to configure + the Base Address Register in order for the host to assign PCI addr space. + Register space of the function driver is usually configured + using this API. + +*) pci_epc_clear_bar() + + The PCI endpoint function driver should use pci_epc_clear_bar() to reset + the BAR. + +*) pci_epc_raise_irq() + + The PCI endpoint function driver should use pci_epc_raise_irq() to raise + Legacy Interrupt or MSI Interrupt. + +*) pci_epc_mem_alloc_addr() + + The PCI endpoint function driver should use pci_epc_mem_alloc_addr(), to + allocate memory address from EPC addr space which is required to access + RC's buffer + +*) pci_epc_mem_free_addr() + + The PCI endpoint function driver should use pci_epc_mem_free_addr() to + free the memory space allocated using pci_epc_mem_alloc_addr(). + +2.1.3 Other APIs + +There are other APIs provided by the EPC library. These are used for binding +the EPF device with EPC device. pci-ep-cfs.c can be used as reference for +using these APIs. + +*) pci_epc_get() + + Get a reference to the PCI endpoint controller based on the device name of + the controller. + +*) pci_epc_put() + + Release the reference to the PCI endpoint controller obtained using + pci_epc_get() + +*) pci_epc_add_epf() + + Add a PCI endpoint function to a PCI endpoint controller. A PCIe device + can have up to 8 functions according to the specification. + +*) pci_epc_remove_epf() + + Remove the PCI endpoint function from PCI endpoint controller. + +*) pci_epc_start() + + The PCI endpoint function driver should invoke pci_epc_start() once it + has configured the endpoint function and wants to start the PCI link. + +*) pci_epc_stop() + + The PCI endpoint function driver should invoke pci_epc_stop() to stop + the PCI LINK. + +2.2 PCI Endpoint Function(EPF) Library + +The EPF library provides APIs to be used by the function driver and the EPC +library to provide endpoint mode functionality. + +2.2.1 APIs for the PCI Endpoint Function Driver + +This section lists the APIs that the PCI Endpoint core provides to be used +by the PCI endpoint function driver. + +*) pci_epf_register_driver() + + The PCI Endpoint Function driver should implement the following ops: + * bind: ops to perform when a EPC device has been bound to EPF device + * unbind: ops to perform when a binding has been lost between a EPC + device and EPF device + * linkup: ops to perform when the EPC device has established a + connection with a host system + + The PCI Function driver can then register the PCI EPF driver by using + pci_epf_register_driver(). + +*) pci_epf_unregister_driver() + + The PCI Function driver can unregister the PCI EPF driver by using + pci_epf_unregister_driver(). + +*) pci_epf_alloc_space() + + The PCI Function driver can allocate space for a particular BAR using + pci_epf_alloc_space(). + +*) pci_epf_free_space() + + The PCI Function driver can free the allocated space + (using pci_epf_alloc_space) by invoking pci_epf_free_space(). + +2.2.2 APIs for the PCI Endpoint Controller Library +This section lists the APIs that the PCI Endpoint core provides to be used +by the PCI endpoint controller library. + +*) pci_epf_linkup() + + The PCI endpoint controller library invokes pci_epf_linkup() when the + EPC device has established the connection to the host. + +2.2.2 Other APIs +There are other APIs provided by the EPF library. These are used to notify +the function driver when the EPF device is bound to the EPC device. +pci-ep-cfs.c can be used as reference for using these APIs. + +*) pci_epf_create() + + Create a new PCI EPF device by passing the name of the PCI EPF device. + This name will be used to bind the the EPF device to a EPF driver. + +*) pci_epf_destroy() + + Destroy the created PCI EPF device. + +*) pci_epf_bind() + + pci_epf_bind() should be invoked when the EPF device has been bound to + a EPC device. + +*) pci_epf_unbind() + + pci_epf_unbind() should be invoked when the binding between EPC device + and EPF device is lost. diff --git a/Documentation/PCI/endpoint/pci-test-function.txt b/Documentation/PCI/endpoint/pci-test-function.txt new file mode 100644 index 000000000000..0c519c9bf94a --- /dev/null +++ b/Documentation/PCI/endpoint/pci-test-function.txt @@ -0,0 +1,66 @@ + PCI TEST + Kishon Vijay Abraham I <kishon@ti.com> + +Traditionally PCI RC has always been validated by using standard +PCI cards like ethernet PCI cards or USB PCI cards or SATA PCI cards. +However with the addition of EP-core in linux kernel, it is possible +to configure a PCI controller that can operate in EP mode to work as +a test device. + +The PCI endpoint test device is a virtual device (defined in software) +used to test the endpoint functionality and serve as a sample driver +for other PCI endpoint devices (to use the EP framework). + +The PCI endpoint test device has the following registers: + + 1) PCI_ENDPOINT_TEST_MAGIC + 2) PCI_ENDPOINT_TEST_COMMAND + 3) PCI_ENDPOINT_TEST_STATUS + 4) PCI_ENDPOINT_TEST_SRC_ADDR + 5) PCI_ENDPOINT_TEST_DST_ADDR + 6) PCI_ENDPOINT_TEST_SIZE + 7) PCI_ENDPOINT_TEST_CHECKSUM + +*) PCI_ENDPOINT_TEST_MAGIC + +This register will be used to test BAR0. A known pattern will be written +and read back from MAGIC register to verify BAR0. + +*) PCI_ENDPOINT_TEST_COMMAND: + +This register will be used by the host driver to indicate the function +that the endpoint device must perform. + +Bitfield Description: + Bit 0 : raise legacy IRQ + Bit 1 : raise MSI IRQ + Bit 2 - 7 : MSI interrupt number + Bit 8 : read command (read data from RC buffer) + Bit 9 : write command (write data to RC buffer) + Bit 10 : copy command (copy data from one RC buffer to another + RC buffer) + +*) PCI_ENDPOINT_TEST_STATUS + +This register reflects the status of the PCI endpoint device. + +Bitfield Description: + Bit 0 : read success + Bit 1 : read fail + Bit 2 : write success + Bit 3 : write fail + Bit 4 : copy success + Bit 5 : copy fail + Bit 6 : IRQ raised + Bit 7 : source address is invalid + Bit 8 : destination address is invalid + +*) PCI_ENDPOINT_TEST_SRC_ADDR + +This register contains the source address (RC buffer address) for the +COPY/READ command. + +*) PCI_ENDPOINT_TEST_DST_ADDR + +This register contains the destination address (RC buffer address) for +the COPY/WRITE command. diff --git a/Documentation/PCI/endpoint/pci-test-howto.txt b/Documentation/PCI/endpoint/pci-test-howto.txt new file mode 100644 index 000000000000..75f48c3bb191 --- /dev/null +++ b/Documentation/PCI/endpoint/pci-test-howto.txt @@ -0,0 +1,179 @@ + PCI TEST USERGUIDE + Kishon Vijay Abraham I <kishon@ti.com> + +This document is a guide to help users use pci-epf-test function driver +and pci_endpoint_test host driver for testing PCI. The list of steps to +be followed in the host side and EP side is given below. + +1. Endpoint Device + +1.1 Endpoint Controller Devices + +To find the list of endpoint controller devices in the system: + + # ls /sys/class/pci_epc/ + 51000000.pcie_ep + +If PCI_ENDPOINT_CONFIGFS is enabled + # ls /sys/kernel/config/pci_ep/controllers + 51000000.pcie_ep + +1.2 Endpoint Function Drivers + +To find the list of endpoint function drivers in the system: + + # ls /sys/bus/pci-epf/drivers + pci_epf_test + +If PCI_ENDPOINT_CONFIGFS is enabled + # ls /sys/kernel/config/pci_ep/functions + pci_epf_test + +1.3 Creating pci-epf-test Device + +PCI endpoint function device can be created using the configfs. To create +pci-epf-test device, the following commands can be used + + # mount -t configfs none /sys/kernel/config + # cd /sys/kernel/config/pci_ep/ + # mkdir functions/pci_epf_test/func1 + +The "mkdir func1" above creates the pci-epf-test function device that will +be probed by pci_epf_test driver. + +The PCI endpoint framework populates the directory with the following +configurable fields. + + # ls functions/pci_epf_test/func1 + baseclass_code interrupt_pin revid subsys_vendor_id + cache_line_size msi_interrupts subclass_code vendorid + deviceid progif_code subsys_id + +The PCI endpoint function driver populates these entries with default values +when the device is bound to the driver. The pci-epf-test driver populates +vendorid with 0xffff and interrupt_pin with 0x0001 + + # cat functions/pci_epf_test/func1/vendorid + 0xffff + # cat functions/pci_epf_test/func1/interrupt_pin + 0x0001 + +1.4 Configuring pci-epf-test Device + +The user can configure the pci-epf-test device using configfs entry. In order +to change the vendorid and the number of MSI interrupts used by the function +device, the following commands can be used. + + # echo 0x104c > functions/pci_epf_test/func1/vendorid + # echo 0xb500 > functions/pci_epf_test/func1/deviceid + # echo 16 > functions/pci_epf_test/func1/msi_interrupts + +1.5 Binding pci-epf-test Device to EP Controller + +In order for the endpoint function device to be useful, it has to be bound to +a PCI endpoint controller driver. Use the configfs to bind the function +device to one of the controller driver present in the system. + + # ln -s functions/pci_epf_test/func1 controllers/51000000.pcie_ep/ + +Once the above step is completed, the PCI endpoint is ready to establish a link +with the host. + +1.6 Start the Link + +In order for the endpoint device to establish a link with the host, the _start_ +field should be populated with '1'. + + # echo 1 > controllers/51000000.pcie_ep/start + +2. RootComplex Device + +2.1 lspci Output + +Note that the devices listed here correspond to the value populated in 1.4 above + + 00:00.0 PCI bridge: Texas Instruments Device 8888 (rev 01) + 01:00.0 Unassigned class [ff00]: Texas Instruments Device b500 + +2.2 Using Endpoint Test function Device + +pcitest.sh added in tools/pci/ can be used to run all the default PCI endpoint +tests. Before pcitest.sh can be used pcitest.c should be compiled using the +following commands. + + cd <kernel-dir> + make headers_install ARCH=arm + arm-linux-gnueabihf-gcc -Iusr/include tools/pci/pcitest.c -o pcitest + cp pcitest <rootfs>/usr/sbin/ + cp tools/pci/pcitest.sh <rootfs> + +2.2.1 pcitest.sh Output + # ./pcitest.sh + BAR tests + + BAR0: OKAY + BAR1: OKAY + BAR2: OKAY + BAR3: OKAY + BAR4: NOT OKAY + BAR5: NOT OKAY + + Interrupt tests + + LEGACY IRQ: NOT OKAY + MSI1: OKAY + MSI2: OKAY + MSI3: OKAY + MSI4: OKAY + MSI5: OKAY + MSI6: OKAY + MSI7: OKAY + MSI8: OKAY + MSI9: OKAY + MSI10: OKAY + MSI11: OKAY + MSI12: OKAY + MSI13: OKAY + MSI14: OKAY + MSI15: OKAY + MSI16: OKAY + MSI17: NOT OKAY + MSI18: NOT OKAY + MSI19: NOT OKAY + MSI20: NOT OKAY + MSI21: NOT OKAY + MSI22: NOT OKAY + MSI23: NOT OKAY + MSI24: NOT OKAY + MSI25: NOT OKAY + MSI26: NOT OKAY + MSI27: NOT OKAY + MSI28: NOT OKAY + MSI29: NOT OKAY + MSI30: NOT OKAY + MSI31: NOT OKAY + MSI32: NOT OKAY + + Read Tests + + READ ( 1 bytes): OKAY + READ ( 1024 bytes): OKAY + READ ( 1025 bytes): OKAY + READ (1024000 bytes): OKAY + READ (1024001 bytes): OKAY + + Write Tests + + WRITE ( 1 bytes): OKAY + WRITE ( 1024 bytes): OKAY + WRITE ( 1025 bytes): OKAY + WRITE (1024000 bytes): OKAY + WRITE (1024001 bytes): OKAY + + Copy Tests + + COPY ( 1 bytes): OKAY + COPY ( 1024 bytes): OKAY + COPY ( 1025 bytes): OKAY + COPY (1024000 bytes): OKAY + COPY (1024001 bytes): OKAY |