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path: root/drivers/fsi
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2018-06-12fsi/sbefifo: Add driver for the SBE FIFOBenjamin Herrenschmidt
This driver provides an in-kernel and a user API for accessing the command FIFO of the SBE (Self Boot Engine) of the POWER9 processor, via the FSI bus. It provides an in-kernel interface to submit command and receive responses, along with a helper to locate and analyse the response status block. It's a simple synchronous submit() type API. The user interface uses the write/read interface that an earlier version of this driver already provided, however it has some specific limitations in order to keep the driver simple and avoid using up a lot of kernel memory: - The user should perform a single write() with the command and a single read() to get the response (with a buffer big enough to hold the entire response). - On a write() the command is simply "stored" into a kernel buffer, it is submitted as one operation on the subsequent read(). This allows to have the code write directly from the FIFO into the user buffer and avoid hogging the SBE between the write() and read() syscall as it's critical that the SBE be freed asap to respond to the host. An extra write() will simply replace the previously written command. - A write of a single 4 bytes containing the value 0x52534554 in big endian will trigger a reset request. No read is necessary, the write() call will return when the reset has been acknowledged or times out. - The command is limited to 4K bytes. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Tested-by: Joel Stanley <joel@jms.id.au> ---
2018-06-12fsi: scom: Remove PIB reset during probeEddie James
The PIB reset causes problems for the running P9 chip. The reset shouldn't be performed by this driver. Signed-off-by: Eddie James <eajames@linux.vnet.ibm.com> Reviewed-by: Christopher Bostic <cbostic@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Tested-by: Joel Stanley <joel@jms.id.au>
2018-06-12fsi/master-gpio: Replace bit_bit lock with IRQ disable/enableJeremy Kerr
We currently use a spinlock (bit_lock) around operations that clock bits out of the FSI bus, and a mutex to protect against simultaneous access to the master. This means that bit_lock isn't needed for mutual exlusion, only to prevent timing issues when clocking bits out. To reflect this, this change converts bit_lock to just the local_irq_save/restore operation. Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Tested-by: Joel Stanley <joel@jms.id.au>
2018-06-12fsi/fsi-master-gpio: More error handling cleanupBenjamin Herrenschmidt
Remove calls to the empty and useless fsi_master_gpio_error() function, and report CRC errors as "FSI_ERR_NO_SLAVE" when reading an all 1's response. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Tested-by: Joel Stanley <joel@jms.id.au>
2018-06-12fsi/fsi-master-gpio: Implement CRC error recoveryBenjamin Herrenschmidt
The FSI protocol defines two modes of recovery from CRC errors, this implements both: - If the device returns an ECRC (it detected a CRC error in the command), then we simply issue the command again. - If the master detects a CRC error in the response, we send an E_POLL command which requests a resend of the response without actually re-executing the command (which could otherwise have unwanted side effects such as dequeuing a FIFO twice). Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Reviewed-by: Christopher Bostic <cbostic@linux.vnet.ibm.com> Tested-by: Joel Stanley <joel@jms.id.au> --- Note: This was actually tested by removing some of my fixes, thus causing us to hit occasional CRC errors during high LPC activity.
2018-06-12fsi/gpio: Use relative-addressing commandsJeremy Kerr
FSI CFAMs support shorter commands that use a relative (or same) address as the last. This change introduces a last_addr to the master state, and uses it for subsequent reads/writes, and performs relative addressing when a subsequent read/write is in range. Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Reviewed-by: Christopher Bostic <cbostic@linux.vnet.ibm.com> Tested-by: Joel Stanley <joel@jms.id.au>
2018-06-12fsi/gpio: Include command build in locked sectionJeremy Kerr
For implementing relative addressing mode, we'll need to build a command that is coherent with CFAM state. To do that, include the build_command_* functions in the locked section of read/write/term. Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Tested-by: Joel Stanley <joel@jms.id.au>
2018-06-12fsi/fsi-master-gpio: Delay sampling of FSI data inputBenjamin Herrenschmidt
Most SoC GPIO implementations, including the Aspeed one, have synchronizers on the GPIO inputs. This means that the value read from a GPIO is a couple of clocks old, from whatever clock source feeds those synchronizers. In practice, this means that in no-delay mode, we are using a value that can potentially be a bit too old and too close to the clock edge establishing the data on the other side of the link. The voltage converters we use on some systems make this worse and sensitive to things like voltage fluctuations etc... This is, we believe, the cause of occasional CRC errors encountered during heavy activity on the LPC bus. This is fixed by introducing a dummy GPIO read before the actual data read. It slows down SBEFIFO by about 15% (less than any delay primitive) and the end result is so far solid. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Reviewed-by: Christopher Bostic <cbostic@linux.vnet.ibm.com> Tested-by: Joel Stanley <joel@jms.id.au>
2018-06-12fsi/fsi-master-gpio: Reduce dpoll clocksBenjamin Herrenschmidt
FSI_GPIO_DPOLL_CLOCKS is the number of clocks before sending a DPOLL command after receiving a BUSY status. It should be at least tSendDelay (16 clocks). According to comments in the code, it needs to also be at least 21 clocks due to HW issues. It's currently 100 clocks which impacts performances negatively in some cases. Reduces it in half to 50 clocks which seems to still be solid. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Reviewed-by: Christopher Bostic <cbostic@linux.vnet.ibm.com> Tested-by: Joel Stanley <joel@jms.id.au>
2018-06-12fsi/fsi-master-gpio: Reduce turnaround clocksBenjamin Herrenschmidt
FSI_GPIO_PRIME_SLAVE_CLOCKS is the number of clocks if the "idle" phase between the end of a response and the beginning of the next one. It corresponds to tSendDelay in the FSI specification. The default value in the slave is 16 clocks. 100 is way overkill and significantly reduces the driver performance. This changes it to 20 (which gives the HW a bit of margin still just in case). Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Reviewed-by: Christopher Bostic <cbostic@linux.vnet.ibm.com> Tested-by: Joel Stanley <joel@jms.id.au>
2018-06-12fsi/fsi-master-gpio: Add "no-gpio-delays" optionBenjamin Herrenschmidt
This adds support for an optional device-tree property that makes the driver skip all the delays around clocking the GPIOs and set it in the device-tree of common POWER9 based OpenPower platforms. This useful on chips like the AST2500 where the GPIO block is running at a fairly low clock frequency (25Mhz typically). In this case, the delays are unnecessary and due to the low precision of the timers, actually quite harmful in terms of performance. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Reviewed-by: Christopher Bostic <cbostic@linux.vnet.ibm.com> Tested-by: Joel Stanley <joel@jms.id.au>
2018-06-12fsi/fsi-master-gpio: Sample input data on different clock phaseBenjamin Herrenschmidt
We currently sample the input data right after we toggle the clock low, then high. The slave establishes the data on the rising edge, so this is not ideal. We should sample it on the low phase instead. This currently works because we have an extra delay, but subsequent patches will remove it. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Reviewed-by: Christopher Bostic <cbostic@linux.vnet.ibm.com> Tested-by: Joel Stanley <joel@jms.id.au>
2018-06-12fsi: gpio: Use a mutex to protect transfersJeremy Kerr
Reduce time spent with interrupts disabled by limiting the critical sections to bitbanging FSI symbols. We only need to ensure exclusive use of the bus for an entire transfer, not that the transfer be performed in atomic context. Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Tested-by: Joel Stanley <joel@jms.id.au>
2018-06-12fsi: gpio: Remove unused 'id' variableAndrew Jeffery
Signed-off-by: Andrew Jeffery <andrew@aj.id.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Tested-by: Joel Stanley <joel@jms.id.au>
2018-06-12fsi: gpio: Trace busy countAndrew Jeffery
An observation from trace output of the existing FSI tracepoints was that the remote device was sometimes reporting as busy. Add a new tracepoint reporting the busy count in order to get a better grip on how often this is the case. Signed-off-by: Andrew Jeffery <andrew@aj.id.au> Acked-by: Eddie James <eajames@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Tested-by: Joel Stanley <joel@jms.id.au>
2018-03-14fsi: core: Add check for master property no-scan-on-initChristopher Bostic
Prior to scanning a master check if the optional property no-scan-on-init is present. If it is then avoid scanning. This is necessary in cases where a master scan could interfere with another FSI master on the same bus. Signed-off-by: Christopher Bostic <cbostic@linux.vnet.ibm.com> Acked-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-14fsi: master: Clarify master lifetimes & fix use-after-free in hub masterJeremy Kerr
Once we call fsi_master_unregister, the core will put_device, potentially freeing the hub master. This change adds a comment explaining the lifetime of an allocated fsi_master. We then add a reference from the driver to the hub master, so it stays around until we've finished ->remove(). Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Tested-by: Christopher Bostic <cbostic@linux.vnet.ibm.com> Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-14fsi: core: Reduce console output during normal scanChristopher Bostic
To reduce amount of console output during boot / power up make all normal path scan related messages debug type. Signed-off-by: Christopher Bostic <cbostic@linux.vnet.ibm.com> Acked-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-14fsi: Match fsi slaves and engines to available dt nodesJeremy Kerr
This change populates device tree nodes for scanned FSI slaves and engines. If the master populates ->of_node of the FSI master device, we'll look for matching slaves, and under those slaves we'll look for matching engines. This means that FSI drivers will have their ->of_node pointer populated if there's a corresponding DT node, which they can use for further device discover. Presence of device tree nodes is optional, and only required for fsi device drivers that need extra properties, or subordinate devices, to be enumerated. Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-14fsi: Fix one and two byte bus reads/writesEddie James
Address checker fixed to allow one and two byte reads/writes. Address alignments for each size verified. Signed-off-by: Edward James <eajames@us.ibm.com> Signed-off-by: Christopher Bostic <cbostic@linux.vnet.ibm.com> Acked-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-14fsi: master-gpio: Add external modeJeremy Kerr
This change introduces an 'external mode' for GPIO-based FSI masters, allowing the clock and data lines to be driven by an external source. For example, external mode is selected by a user when an external debug device is attached to the FSI pins. To do this, we need to set specific states for the trans, mux and enable GPIOs, and prevent access to clk & data from the FSI core code (by returning EBUSY). External mode is controlled by a sysfs attribute, so add the relevant information to Documentation/ABI/ Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Reviewed-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-14fsi: master-gpio: Add locking during break and link enableJeremy Kerr
Currently, we perform GPIO accesses in fsi_master_gpio_break and fsi_master_link_enable, without holding cmd_lock. This change adds the appropriate locking. Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Reviewed-by: Joel Stanley <joel@jms.id.au> Reviewed-by: Christopher Bostic <clbostic@linux.vnet.ibm.com> Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-14fsi: Add fsi_master_rescan()Jeremy Kerr
We'll want non-core fsi code to trigger a rescan, so introduce a non-static fsi_master_rescan() function. Use this for the existing unscan/scan behaviour too. Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Reviewed-by: Joel Stanley <joel@jms.id.au> Reviewed-by: Christopher Bostic <clbostic@linux.vnet.ibm.com> Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-07fsi: Make FSI a menuconfig to ease disabling it allVincent Legoll
No need to get into the submenu to disable all FSI-related config entries Signed-off-by: Vincent Legoll <vincent.legoll@gmail.com> Acked-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-04drivers/fsi: make a couple of functions staticColin Ian King
The functions fsi_slave_report_and_clear_errors and fsi_slave_handle_error are local to the source and do not need to be in global scope, so make them static. Cleans up sparse warnings: symbol 'fsi_slave_report_and_clear_errors' was not declared. Should it be static? symbol 'fsi_slave_handle_error' was not declared. Should it be static? Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-28drivers/fsi/scom: Remove reset before every putscomEdward A. James
Reset causes problems for operations requiring multiple scoms (e.g. i2c over scom). Instead, reset scom engine during probe. Signed-off-by: Edward A. James <eajames@us.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-28drivers/fsi: add const to bin_attribute structuresBhumika Goyal
Declare bin_attribute structures as const as they are only passed as an argument to the function device_create_bin_file. This argument is of type const, so declare the structure as const. Signed-off-by: Bhumika Goyal <bhumirks@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-17drivers/fsi: fix fsi_slave_mode prototypeArnd Bergmann
gcc warns about the return type of this function: drivers/fsi/fsi-core.c:535:8: error: type qualifiers ignored on function return type [-Werror=ignored-qualifiers] This removes the 'const' attribute, as suggested by the warning. Fixes: 2b37c3e285f9 ("drivers/fsi: Set slave SMODE to init communication") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-17fsi: core: register with postcore_initcallJoel Stanley
When testing an i2c driver that is a fsi bus driver, I saw the following oops: kernel BUG at drivers/base/driver.c:153! Internal error: Oops - BUG: 0 [#1] ARM [<8027cb1c>] (driver_register) from [<80344e88>] (fsi_driver_register+0x2c/0x38) [<80344e88>] (fsi_driver_register) from [<805f5ebc>] (fsi_i2c_driver_init+0x1c/0x24) [<805f5ebc>] (fsi_i2c_driver_init) from [<805d1f14>] (do_one_initcall+0xb4/0x170) [<805d1f14>] (do_one_initcall) from [<805d20f0>] (kernel_init_freeable+0x120/0x1dc) [<805d20f0>] (kernel_init_freeable) from [<8043f4a8>] (kernel_init+0x18/0x104) [<8043f4a8>] (kernel_init) from [<8000a5e8>] (ret_from_fork+0x14/0x2c) This is because the fsi bus had not been registered. This fix registers the bus with postcore_initcall instead, to ensure it is registered earlier on. When the fsi core is used as a module this should not be a problem as the fsi driver will depend on the fsi bus type symbol, and will therefore load the core before the driver. Fixes: 0508ad1fff11 ("drivers/fsi: Add empty fsi bus definitions") Signed-off-by: Joel Stanley <joel@jms.id.au> Acked-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09drivers/fsi: Add module license to core driverChristopher Bostic
Add missing MODULE_LICENSE("GPL") to the core FSI driver. Signed-off-by: Christopher Bostic <cbostic@linux.vnet.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09drivers/fsi: Use asynchronous slave modeJeremy Kerr
For slaves that are behind a software-clocked master, we want FSI CFAMs to run asynchronously to the FSI clock, so set up our slaves to be in async mode. Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Christopher Bostic <cbostic@linux.vnet.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09drivers/fsi: Add hub master supportChristopher Bostic
Add an engine driver to expose a "hub" FSI master - which has a set of control registers in the engine address space, and uses a chunk of the slave address space for actual FSI communication. Additional changes from Jeremy Kerr <jk@ozlabs.org>. Signed-off-by: Christopher Bostic <cbostic@linux.vnet.ibm.com> Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09drivers/fsi: Add SCOM FSI client device driverChristopher Bostic
Create a simple SCOM engine device driver that reads and writes its control registers via an FSI bus. Includes changes from Edward A. James <eajames@us.ibm.com>. Signed-off-by: Christopher Bostic <cbostic@linux.vnet.ibm.com> Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Edward A. James <eajames@us.ibm.com> Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09drivers/fsi/gpio: Add tracepoints for GPIO masterJeremy Kerr
Trace low level input/output GPIO operations. Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Christopher Bostic <cbostic@linux.vnet.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09drivers/fsi: Add GPIO based FSI masterChristopher Bostic
Implement a FSI master using GPIO. Will generate FSI protocol for read and write commands to particular addresses. Sends master command and waits for and decodes a slave response. Includes changes from Edward A. James <eajames@us.ibm.com> and Jeremy Kerr <jk@ozlabs.org>. Signed-off-by: Edward A. James <eajames@us.ibm.com> Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Christopher Bostic <cbostic@linux.vnet.ibm.com> Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09drivers/fsi: Add error handling for slaveJeremy Kerr
This change implements error handling in the FSI core, by cleaining up and retrying failed operations, using the SISC, TERM and BREAK facilities. Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Christopher Bostic <cbostic@linux.vnet.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09drivers/fsi: Add tracepoints for low-level operationsJeremy Kerr
Trace low level read and write FSI bus operations. Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Christopher Bostic <cbostic@linux.vnet.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09drivers/fsi: expose direct-access slave APIJeremy Kerr
Allow drivers to access the slave address ranges. Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Christopher Bostic <cbostic@linux.vnet.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09drivers/fsi: Add sysfs files for FSI master & slave accessesJeremy Kerr
This change adds a 'raw' file for reads & writes, and a 'term' file for the TERM command, and a 'break' file for issuing a BREAK. Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Christopher Bostic <cbostic@linux.vnet.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09drivers/fsi: Add client driver register utilitiesChristopher Bostic
Add driver_register and driver_unregister wrappers for FSI. Signed-off-by: Christopher Bostic <cbostic@linux.vnet.ibm.com> Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09drivers/fsi: Add master unscanChristopher Bostic
Allow a master to undo a previous scan. Should a master scan a bus twice it will need to ensure it doesn't double register any previously detected device. Signed-off-by: Christopher Bostic <cbostic@linux.vnet.ibm.com> Signed-off-by: Joel Stanley <joel@jms.id.au> ---- v7 - Unscan when unregistering master - Remove leading '__'s from function names - Return fail state for sysfs rescan file Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09drivers/fsi: Add device read/write/peek APIJeremy Kerr
This change introduces the fsi device API: simple read, write and peek accessors for the devices' address spaces. Includes contributions from Christopher Bostic <cbostic@linux.vnet.ibm.com> and Edward A. James <eajames@us.ibm.com>. Signed-off-by: Edward A. James <eajames@us.ibm.com> Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Christopher Bostic <cbostic@linux.vnet.ibm.com> Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09drivers/fsi: scan slaves & register devicesJeremy Kerr
Now that we have fsi_slave devices, scan each for endpoints, and register them on the fsi bus. Includes contributions from Christopher Bostic <cbostic@linux.vnet.ibm.com>. Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Christopher Bostic <cbostic@linux.vnet.ibm.com> Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09drivers/fsi: Set slave SMODE to init communicationChristopher Bostic
Set CFAM to appropriate ID so that the controlling master can manage link memory ranges. Add slave engine register definitions. Includes changes from Jeremy Kerr <jk@ozlabs.org>. Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Christopher Bostic <cbostic@linux.vnet.ibm.com> Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09drivers/fsi: Implement slave initialisationJeremy Kerr
Implement fsi_slave_init: if we can read a chip ID, create fsi_slave devices and register with the driver core. Includes changes from Christopher Bostic <cbostic@linux.vnet.ibm.com>. Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Christopher Bostic <cbostic@linux.vnet.ibm.com> Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09drivers/fsi: Set up links for slave communicationChristopher Bostic
Enable each link and send a break command, and try to detect a slave by reading from the SMODE register. Signed-off-by: Christopher Bostic <cbostic@linux.vnet.ibm.com> Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09drivers/fsi: Add slave & master read/write APIsJeremy Kerr
Introduce functions to perform reads/writes on the slave address space; these simply pass the request on the slave's master with the correct link and slave ID. We implement these on top of similar helpers for the master. Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Chris Bostic <cbostic@linux.vnet.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09drivers/fsi: Add empty master scanJeremy Kerr
When a new fsi master is added, we will need to scan its links, and slaves attached to those links. This change introduces a little shell to iterate the links, which we will populate with the actual slave scan in a later change. Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Chris Bostic <cbostic@linux.vnet.ibm.com> Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09drivers/fsi: Add slave definitionJeremy Kerr
Add the initial fsi slave device, which is private to the core code. This will be a child of the master, and parent to endpoint devices. Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Chris Bostic <cbostic@linux.vnet.ibm.com> Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09drivers/fsi: Add fsi master definitionJeremy Kerr
Add a `struct fsi_master` to represent a FSI master controller. FSI master drivers register one of these structs to provide device-specific of the standard operations: read/write/term/break and link control. Includes changes from Edward A. James <eajames@us.ibm.com> & Jeremy Kerr <jk@ozlabs.org>. Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Chris Bostic <cbostic@linux.vnet.ibm.com> Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>