READ/WRITE proved to be actively confusing - the meanings are
"data destination, as used with read(2)" and "data source, as
used with write(2)", but people keep interpreting those as
"we read data from it" and "we write data to it", i.e. exactly
the wrong way.
Call them ITER_DEST and ITER_SOURCE - at least that is harder
to misinterpret...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Provide more output on the timeout status, and make some vdbg calls into
dbg calls so they can be enabled at runtime.
Signed-off-by: Joel Stanley <joel@jms.id.au>
Link: https://lore.kernel.org/r/20220415050757.281158-1-joel@jms.id.au
Signed-off-by: Joel Stanley <joel@jms.id.au>
FSI_SBEFIFO_READ_TIMEOUT_SECONDS ioctl sets the read timeout (in
seconds) for the response received by sbefifo device from sbe. The
timeout affects only the read operation on current sbefifo device fd.
Certain SBE operations can take long time to complete and the default
timeout of 10 seconds might not be sufficient to start receiving
response from SBE. In such cases, allow the timeout to be set to the
maximum of 120 seconds.
The kernel does not contain the definition of the various SBE
operations, so we must expose an interface to userspace to set the
timeout for the given operation.
Signed-off-by: Amitay Isaacs <amitay@ozlabs.org>
Signed-off-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Eddie James <eajames@linux.ibm.com>
Link: https://lore.kernel.org/r/20220121053816.82253-3-joel@jms.id.au
Signed-off-by: Joel Stanley <joel@jms.id.au>
For some of the chip-ops where sbe needs to collect trace information,
sbe can take a long time (>30s) to respond. Currently these chip-ops
will timeout as the start of response timeout defaults to 10s.
Instead of default value, use specified value. The require timeout
value will be set using ioctl.
Signed-off-by: Amitay Isaacs <amitay@ozlabs.org>
Signed-off-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Eddie James <eajames@linux.ibm.com>
Link: https://lore.kernel.org/r/20220121053816.82253-2-joel@jms.id.au
Signed-off-by: Joel Stanley <joel@jms.id.au>
Some SBE operations have extremely large responses and can require
several minutes to process the response. During this time, the device
lock must be held. If another process attempts an operation, it will
wait for the mutex for longer than the kernel hung task watchdog
allows. Therefore, use the interruptible function to lock the mutex.
Signed-off-by: Eddie James <eajames@linux.ibm.com>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Link: https://lore.kernel.org/r/20210803213016.44739-1-eajames@linux.ibm.com
Signed-off-by: Joel Stanley <joel@jms.id.au>
The SBEFIFO timeout error requires special handling in userspace
to do recovery operations. Add a sysfs file to indicate a timeout
error, and notify pollers when a timeout occurs.
This will be used by the openpower-occ-control application.
Signed-off-by: Eddie James <eajames@linux.ibm.com>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Link: https://lore.kernel.org/r/20211019211749.38059-3-eajames@linux.ibm.com
Signed-off-by: Joel Stanley <joel@jms.id.au>
On BMCs with lower timer resolution than 1ms, msleep(1) will take
way longer than 1ms, so looping 10k times won't wait for 10s but
significantly longer.
Fix this by using jiffies like the rest of the code.
Fixes: 9f4a8a2d7f ("fsi/sbefifo: Add driver for the SBE FIFO")
Signed-off-by: Joachim Fenkes <fenkes@de.ibm.com>
Link: https://lore.kernel.org/r/20200724071518.430515-3-joel@jms.id.au
Signed-off-by: Joel Stanley <joel@jms.id.au>
When the SBE requests a reset via the down FIFO, that is also the
FIFO we should go and reset ;)
Fixes: 9f4a8a2d7f ("fsi/sbefifo: Add driver for the SBE FIFO")
Signed-off-by: Joachim Fenkes <FENKES@de.ibm.com>
Signed-off-by: Joel Stanley <joel@jms.id.au>
Link: https://lore.kernel.org/r/20200724071518.430515-2-joel@jms.id.au
Signed-off-by: Joel Stanley <joel@jms.id.au>
The only usage of sbefifo_ids is to assign its address to the id_table
field in the fsi_driver struct, which is a const pointer, so make it
const to allow the compiler to put it in read-only memory
Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Signed-off-by: Joel Stanley <joel@jms.id.au>
SBE fifo operations should be allowed while the SBE is in any of the
"IPL" states. Operations should succeed in this state.
Fixes: 9f4a8a2d7f fsi/sbefifo: Add driver for the SBE FIFO
Reviewed-by: Joel Stanley <joel@jms.id.au>
Tested-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Eddie James <eajames@linux.ibm.com>
Link: https://lore.kernel.org/r/1561575415-3282-1-git-send-email-eajames@linux.ibm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In the iov_iter struct, separate the iterator type from the iterator
direction and use accessor functions to access them in most places.
Convert a bunch of places to use switch-statements to access them rather
then chains of bitwise-AND statements. This makes it easier to add further
iterator types. Also, this can be more efficient as to implement a switch
of small contiguous integers, the compiler can use ~50% fewer compare
instructions than it has to use bitwise-and instructions.
Further, cease passing the iterator type into the iterator setup function.
The iterator function can set that itself. Only the direction is required.
Signed-off-by: David Howells <dhowells@redhat.com>
Otherwise cronus putmem fails istep and BML fails to upload skiboot
To do that, we still use our one-page command buffer for small commands
for speed, and for anything bigger, with a limit of 1MB plus a page,
we vmalloc a temporary buffer.
The limit was chosen because Cronus will break up any data transfer
into 1M chunks (the extra page is for the command header).
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reviewed-by: Andrew Jeffery <andrew@aj.id.au>
This converts FSI sbefifo to use the new fsi-core controlled
chardev allocator and use a real cdev instead of a miscdev.
One side effect is to fix the object lifetime by removing
the use of devm_kzalloc() for something that contains kobjects,
and using proper reference counting.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Some of the exit path missed the unlock. Move the mutex to
an outer function to avoid the problem completely
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
"dev" is dereferences before it's checked.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
There was no unlock of the FFDC mutex.
Fixes: 9f4a8a2d7f ("fsi/sbefifo: Add driver for the SBE FIFO")
Signed-off-by: Eddie James <eajames@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
fsi-sbefifo.c:547:58: warning: incorrect type in argument 2 (different base types)
fsi-sbefifo.c:547:58: expected restricted __be32 [usertype] *word
fsi-sbefifo.c:547:58: got unsigned int *<noident>
fsi-sbefifo.c:635:16: warning: incorrect type in assignment (different base types)
fsi-sbefifo.c:635:16: expected unsigned int [unsigned] <noident>
fsi-sbefifo.c:635:16: got restricted __be32 [usertype] <noident>
fsi-sbefifo.c:636:16: warning: incorrect type in assignment (different base types)
fsi-sbefifo.c:636:16: expected unsigned int [unsigned] <noident>
fsi-sbefifo.c:636:16: got restricted __be32 [usertype] <noident>
Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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>
---
Al Viro
Joel Stanley
Amitay Isaacs
Eddie James
Joachim Fenkes
Rikard Falkeborn
David Howells
Benjamin Herrenschmidt
Eddie James