Commit Graph

12 Commits

Author SHA1 Message Date
Omer Shpigelman
b75f22505a habanalabs: add signal/wait to CS IOCTL operations
Add the following two operations to the CS IOCTL:

Signal:

The signal operation is basically a command submission, that is created by
the driver upon user request. It will be implemented using a dedicated PQE
that will increment a specific SOB. There will be a new flag:
HL_CS_FLAGS_SIGNAL. When the user set this flag in the CS IOCTL structure,
the driver will execute a dedicated code path that will prepare this
special PQE and submit it. The user only needs to provide a queue index on
which to put the signal.

Wait:

The wait operation is also a command submission that is created by the
driver upon user request. It will be implemented using a dedicated PQE that
will contain packets of "ARM a monitor" + FENCE packet. There will be a new
flag: HL_CS_FLAGS_WAIT. When the user set this flag in the CS structure,
the driver will execute a dedicated code path that will prepare this
special PQE and submit it.

The user needs to provide the following parameters:
1. queue ID
2. an array of signal_seq numbers and the number of signals to wait on
   (the length of signal_seq_arr).

The IOCTL will return the CS sequence number of the wait it put on the
queue ID.

Currently, the code supports signal_seq_nr==1. But this API definition will
allow us to put a single PQE that waits on multiple signals.

To correctly configure the monitor and fence, the driver will need to
retrieve the specified signal CS object that contains the relevant SOB and
its expected value. In case the signal CS has already been completed, there
is no point of adding a wait operation. In this case, the driver will
return to the user *without* putting anything on the PQ. The return code
should reflect to the user that the signal was completed, as we won't
return a CS sequence number for this wait.

Signed-off-by: Omer Shpigelman <oshpigelman@habana.ai>
Reviewed-by: Oded Gabbay <oded.gabbay@gmail.com>
Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
2020-05-19 14:48:41 +03:00
Oded Gabbay
018e0e3594 habanalabs: rate limit error msg on waiting for CS
In case a user submits a CS, and the submission fails, and the user doesn't
check the return value and instead use the error return value as a valid
sequence number of a CS and ask to wait on it, the driver will print an
error and return an error code for that wait.

The real problem happens if now the user ignores the error of the wait, and
try to wait again and again. This can lead to a flood of error messages
from the driver and even soft lockup event.

Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
Reviewed-by: Tomer Tayar <ttayar@habana.ai>
2019-12-14 15:12:21 +02:00
Oded Gabbay
4c172bbfaa habanalabs: stop using the acronym KMD
We want to stop using the acronym KMD. Therefore, replace all locations
(except for register names we can't modify) where KMD is written to other
terms such as "Linux kernel driver" or "Host kernel driver", etc.

Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
Reviewed-by: Omer Shpigelman <oshpigelman@habana.ai>
2019-09-05 14:55:27 +03:00
Oded Gabbay
86d5307a6d habanalabs: rename user_ctx as compute_ctx
This patch renames the "user_ctx" field in the device structure to
"compute_ctx". This better reflects the meaning of this context.

In addition, we also check in the ctx_fini() that the debug mode should be
disabled only if the context being destroyed is the compute context. This
has no effect right now as we only have a single process and a single
context, but this makes the code more ready for multiple process support.

Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-05 14:55:26 +03:00
Oded Gabbay
b888751a02 habanalabs: add handle field to context structure
This patch adds a field to the context's structure that will hold a unique
handle for the context.

This will be needed when the user will create the context.

Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-05 14:55:26 +03:00
Oded Gabbay
7aa2227aff habanalabs: initialize MMU context for driver
This patch initializes the MMU structures for the kernel context. This is
needed before we can configure mappings for the kernel context.

Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
2019-05-29 15:27:48 +03:00
Oded Gabbay
19734970c9 habanalabs: force user to set device debug mode
This patch adds the implementation of the HL_DEBUG_OP_SET_MODE opcode in
the DEBUG IOCTL.

It forces the user who wants to debug the device to set the device into
debug mode before he can configure the debug engines. The patch also makes
sure to disable debug mode upon user releasing FD, in case the user forgot
to disable debug mode.

Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
2019-05-04 17:36:06 +03:00
Omer Shpigelman
89225ce4fc habanalabs: halt debug engines on user process close
This patch fix a potential bug where a user's process has closed
unexpectedly without disabling the debug engines. In that case, the debug
engines might continue running but because the user's MMU mappings are
going away, we will get page fault errors.

This behavior is also opposed to the general rule where nothing runs on
the device after the user process closes.

The patch stops the debug H/W engines upon process termination and thus
makes sure nothing runs on the device after the process goes away.

Signed-off-by: Omer Shpigelman <oshpigelman@habana.ai>
Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
2019-05-24 22:46:15 +03:00
Oded Gabbay
027d35d0b6 habanalabs: rename restore to ctx_switch when appropriate
This patch only does renaming of certain variables and structure members,
and their accompanied comments.

This is done to better reflect the actions these variables and members
represent.

There is no functional change in this patch.

Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
2019-04-25 20:15:42 +03:00
Omer Shpigelman
0feaf86d4e habanalabs: add virtual memory and MMU modules
This patch adds the Virtual Memory and MMU modules.

Goya has an internal MMU which provides process isolation on the internal
DDR. The internal MMU also performs translations for transactions that go
from Goya to the Host.

The driver is responsible for allocating and freeing memory on the DDR
upon user request. It also provides an interface to map and unmap DDR and
Host memory to the device address space.

The MMU in Goya supports 3-level and 4-level page tables. With 3-level, the
size of each page is 2MB, while with 4-level the size of each page is 4KB.

In the DDR, the physical pages are always 2MB.

Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Omer Shpigelman <oshpigelman@habana.ai>
Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-18 09:46:46 +01:00
Oded Gabbay
eff6f4a0e7 habanalabs: add command submission module
This patch adds the main flow for the user to submit work to the device.

Each work is described by a command submission object (CS). The CS contains
3 arrays of command buffers: One for execution, and two for context-switch
(store and restore).

For each CB, the user specifies on which queue to put that CB. In case of
an internal queue, the entry doesn't contain a pointer to the CB but the
address in the on-chip memory that the CB resides at.

The driver parses some of the CBs to enforce security restrictions.

The user receives a sequence number that represents the CS object. The user
can then query the driver regarding the status of the CS, using that
sequence number.

In case the CS doesn't finish before the timeout expires, the driver will
perform a soft-reset of the device.

Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-18 09:46:45 +01:00
Oded Gabbay
0861e41de5 habanalabs: add context and ASID modules
This patch adds two modules - ASID and context.

Each user process that opens a device's file must have at least one
context before it is able to "work" with the device. Each context has its
own device address-space and contains information about its runtime state
(its active command submissions).

To have address-space separation between contexts, each context is assigned
a unique ASID, which stands for "address-space id". Goya supports up to
1024 ASIDs.

Currently, the driver doesn't support multiple contexts. Therefore, the
user doesn't need to actively create a context. A "primary context" is
created automatically when the user opens the device's file.

Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-18 09:46:44 +01:00