Depending on the underlying transport, cxlflash has a dependency on either
the CXL or OCXL drivers, which are enabled via their Kconfig option.
Instead of having a module wide dependency on these config options, it is
better to isolate the object modules that are dependent on the CXL and OCXL
drivers and adjust the module dependencies accordingly.
This commit isolates the object files that are dependent on CXL and/or
OCXL. The cxl/ocxl fops used in the core driver are tucked under an ifdef to
avoid compilation errors.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
As a staging cleanup to support transport specific builds of the cxlflash
module, relocate device dependent assignments to header files. This will
avoid littering the core driver with conditional compilation logic.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The new header file, backend.h, that was recently added is missing the
include guards. This commit adds the guards.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
AFUs can only process a single AFU command at a time. This is enforced with
a global mutex situated within the AFU send routine. As this mutex has a
global scope, it has the potential to unnecessarily block commands destined
for other AFUs.
Instead of using a global mutex, transition the mutex to be per-AFU. This
will allow commands to only be blocked by siblings of the same AFU.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
When a superpipe process that makes use of virtual LUNs is terminated or
killed abruptly, there is a possibility that the cxlflash driver could hang
and deprive other operations on the adapter.
The release fop registered to be invoked on a context close, detaches every
LUN associated with the context. The underlying service to detach the LUN
assumes it has been called with the read semaphore held, and releases the
semaphore before any operation that could be time consuming.
When invoked without holding the read semaphore, an opportunity is created
for the semaphore's count to become negative when it is temporarily released
during one of these potential lengthy operations. This negative count
results in subsequent acquisition attempts taking forever, leading to the
hang.
To support the current design point of holding the semaphore on the ioctl()
paths, the release fop should acquire it before invoking any ioctl services.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The kernel log can get filled with debug messages from send_cmd_ioarrin()
when dynamic debug is enabled for the cxlflash module and there is a lot of
legacy I/O traffic.
While these messages are necessary to debug issues that involve command
tracking, the abundance of data can overwrite other useful data in the
log. The best option available is to limit the messages that should serve
most of the common use cases.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The following Oops may be encountered if the device is reset, i.e. EEH
recovery, while there is heavy I/O traffic:
59:mon> t
[c000200db64bb680] c008000009264c40 cxlflash_queuecommand+0x3b8/0x500
[cxlflash]
[c000200db64bb770] c00000000090d3b0 scsi_dispatch_cmd+0x130/0x2f0
[c000200db64bb7f0] c00000000090fdd8 scsi_request_fn+0x3c8/0x8d0
[c000200db64bb900] c00000000067f528 __blk_run_queue+0x68/0xb0
[c000200db64bb930] c00000000067ab80 __elv_add_request+0x140/0x3c0
[c000200db64bb9b0] c00000000068daac blk_execute_rq_nowait+0xec/0x1a0
[c000200db64bba00] c00000000068dbb0 blk_execute_rq+0x50/0xe0
[c000200db64bba50] c0000000006b2040 sg_io+0x1f0/0x520
[c000200db64bbaf0] c0000000006b2e94 scsi_cmd_ioctl+0x534/0x610
[c000200db64bbc20] c000000000926208 sd_ioctl+0x118/0x280
[c000200db64bbcc0] c00000000069f7ac blkdev_ioctl+0x7fc/0xe30
[c000200db64bbd20] c000000000439204 block_ioctl+0x84/0xa0
[c000200db64bbd40] c0000000003f8514 do_vfs_ioctl+0xd4/0xa00
[c000200db64bbde0] c0000000003f8f04 SyS_ioctl+0xc4/0x130
[c000200db64bbe30] c00000000000b184 system_call+0x58/0x6c
When there is no room to send the I/O request, the cached room is refreshed
by reading the memory mapped command room value from the AFU. The AFU
register mapping is refreshed during a reset, creating a race condition that
can lead to the Oops above.
During a device reset, the AFU should not be unmapped until all the active
send threads quiesce. An atomic counter, cmds_active, is currently used to
track internal AFU commands and quiesce during reset. This same counter can
also be used for the active send threads.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The following Oops can occur when there is heavy I/O traffic and the host is
reset by a tool such as sg_reset.
[c000200fff3fbc90] c00800001690117c process_cmd_doneq+0x104/0x500
[cxlflash] (unreliable)
[c000200fff3fbd80] c008000016901648 cxlflash_rrq_irq+0xd0/0x150 [cxlflash]
[c000200fff3fbde0] c000000000193130 __handle_irq_event_percpu+0xa0/0x310
[c000200fff3fbea0] c0000000001933d8 handle_irq_event_percpu+0x38/0x90
[c000200fff3fbee0] c000000000193494 handle_irq_event+0x64/0xb0
[c000200fff3fbf10] c000000000198ea0 handle_fasteoi_irq+0xc0/0x230
[c000200fff3fbf40] c00000000019182c generic_handle_irq+0x4c/0x70
[c000200fff3fbf60] c00000000001794c __do_irq+0x7c/0x1c0
[c000200fff3fbf90] c00000000002a390 call_do_irq+0x14/0x24
[c000200e5828fab0] c000000000017b2c do_IRQ+0x9c/0x130
[c000200e5828fb00] c000000000009b04 h_virt_irq_common+0x114/0x120
When a context is reset, the pending commands are flushed and the AFU is
notified. Before the AFU handles this request there could be command
completion interrupts queued to PHB which are yet to be delivered to the
context. In this scenario, a context could receive an interrupt for a command
that has been flushed, leading to a possible crash when the memory for the
flushed command is accessed.
To resolve this problem, a boolean will indicate if the hardware queue is
ready to process interrupts or not. This can be evaluated in the interrupt
handler before proessing an interrupt.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The following Oops can occur if an internal command sent to the AFU does not
complete within the timeout:
[c000000ff101b810] c008000016020d94 term_mc+0xfc/0x1b0 [cxlflash]
[c000000ff101b8a0] c008000016020fb0 term_afu+0x168/0x280 [cxlflash]
[c000000ff101b930] c0080000160232ec cxlflash_pci_error_detected+0x184/0x230
[cxlflash]
[c000000ff101b9e0] c00800000d95d468 cxl_vphb_error_detected+0x90/0x150[cxl]
[c000000ff101ba20] c00800000d95f27c cxl_pci_error_detected+0xa4/0x240 [cxl]
[c000000ff101bac0] c00000000003eaf8 eeh_report_error+0xd8/0x1b0
[c000000ff101bb20] c00000000003d0b8 eeh_pe_dev_traverse+0x98/0x170
[c000000ff101bbb0] c00000000003f438 eeh_handle_normal_event+0x198/0x580
[c000000ff101bc60] c00000000003fba4 eeh_handle_event+0x2a4/0x338
[c000000ff101bd10] c0000000000400b8 eeh_event_handler+0x1f8/0x200
[c000000ff101bdc0] c00000000013da48 kthread+0x1a8/0x1b0
[c000000ff101be30] c00000000000b528 ret_from_kernel_thread+0x5c/0xb4
When an internal command times out, the command buffer is freed while it is
still in the pending commands list of the context. This corrupts the list and
when the context is cleaned up, a crash is encountered.
To resolve this issue, when an AFU command or TMF command times out, the
command should be deleted from the hardware queue pending command list before
freeing the buffer.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The following Oops can be encountered if a device removal or system shutdown
is initiated while an EEH recovery is in process:
[c000000ff2f479c0] c008000015256f18 cxlflash_pci_slot_reset+0xa0/0x100
[cxlflash]
[c000000ff2f47a30] c00800000dae22e0 cxl_pci_slot_reset+0x168/0x290 [cxl]
[c000000ff2f47ae0] c00000000003ef1c eeh_report_reset+0xec/0x170
[c000000ff2f47b20] c00000000003d0b8 eeh_pe_dev_traverse+0x98/0x170
[c000000ff2f47bb0] c00000000003f80c eeh_handle_normal_event+0x56c/0x580
[c000000ff2f47c60] c00000000003fba4 eeh_handle_event+0x2a4/0x338
[c000000ff2f47d10] c0000000000400b8 eeh_event_handler+0x1f8/0x200
[c000000ff2f47dc0] c00000000013da48 kthread+0x1a8/0x1b0
[c000000ff2f47e30] c00000000000b528 ret_from_kernel_thread+0x5c/0xb4
The remove handler frees AFU memory while the EEH recovery is in progress,
leading to a race condition. This can result in a crash if the recovery thread
tries to access this memory.
To resolve this issue, the cxlflash remove handler will evaluate the device
state and yield to any active reset or probing threads.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit enables the OCXL operations for the OCXL devices.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The cxlflash core driver resets the AFU when the master contexts are created
in the initialization or recovery paths. Today, the OCXL provider service to
perform this operation is pending implementation. To avoid a crash due to a
missing fop, log an error once and return success to continue with execution.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
While enabling a context on the link, a predefined callback can be registered
with the OCXL provider services to be notified on translation errors. These
errors can in turn be passed back to the user on a read operation.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
In order to protect the OCXL hardware contexts from getting clobbered, a
simple state machine is added to indicate when a context is in open, close or
start state. The expected states are validated throughout the code to prevent
illegal operations on a context. A mutex is added to protect writes to the
context state field.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The SISLite specification has been updated to define new synchronous interrupt
status bits. These bits are set by the AFU when a given PASID or EA is bad and
a synchronous interrupt is triggered.
The SISLite header file is updated to support these new bits. Note that there
are also some formatting updates to some of the existing bits to allow all of
the definitions to line up uniformly.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Similar to user contexts, master contexts also require that the per-context
LISN registers be programmed for certain AFUs. The mapped trigger page is
obtained from underlying transport and registered with AFU for each master
context.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The SISLite specification has been updated for OCXL to support communicating
data to generate AFU interrupts to the AFU. This includes a new capability bit
that is advertised for OCXL AFUs and new registers to hold the object handle
and translation PASID of each interrupt. For Power, the object handle is the
mapped trigger page. Note that because these mappings are kernel only, the
PASID of a kernel context must be used to satisfy the translation.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
OCXL requires that AFUs use an opaque object handle to represent an AFU
interrupt. The specification does not provide a common means to communicate
the object handle to the AFU - each AFU must define this within the AFU
specification. To support this model, the object handle must be passed back to
the core driver as it manages the AFU specification (SISLite) for cxlflash.
Note that for Power systems, the object handle is the effective address of the
trigger page.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The cxlflash core fop API requires a way to invoke the fault and release
handlers of underlying transports using their native file-based APIs. This
provides the core with the ability to insert selectively itself into the
processing stream of these operations for cleanup. Implement these two fops to
map and release when requested.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The cxlflash userspace API requires that users be able to mmap and release the
adapter context. Support mapping by implementing the AFU mmap fop to map the
context MMIO space and install the corresponding page table entry upon page
fault. Similarly, implement the AFU release fop to terminate and clean up the
context when invoked.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The cxlflash userspace API requires that users be able to read the adapter
context for any pending events or interrupts from the AFU. Support reading
various events by implementing the AFU read fop to copy out event data.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The cxlflash userspace API requires that users be able to poll the adapter
context for any pending events or interrupts from the AFU. Support polling on
various events by implementing the AFU poll fop using a waitqueue.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
User contexts request interrupts and are started using the "start work"
interface. Populate the start_work() fop to allocate and map interrupts before
starting the user context. As part of starting the context, update the user
process identification logic to properly derive the data required by the
SPA. Also, introduce a skeleton interrupt handler using a bitmap, flag, and
spinlock to track interrupts. This handler will be expanded in future commits.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Add support to map and unmap the irq space and manage irq registrations with
the kernel for each allocated AFU interrupt. Also support mapping the physical
trigger page to obtain an effective address that will be provided to the
cxlflash core in a future commit.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Add support to allocate and free AFU interrupts using the OCXL provider
services. The trigger page returned upon successful allocation will be mapped
and exposed to the cxlflash core in a future commit.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
As part of the context lifecycle, the associated process element within the
Shared Process Area (SPA) of the link must be updated. Each process is defined
by various parameters (pid, tid, PASID mm) that are stored in the SPA upon
starting a context and invalidated when a context is stopped.
Use the OCXL provider services to configure the SPA with the appropriate data
that is unique to the process when starting a context. Initially only kernel
contexts are supported and therefore these process values are not applicable.
Note that the OCXL service used has an optional callback for translation fault
error notification. While not used here, it will be expanded in a future
commit.
Also add a service to stop a context by terminating the corresponding PASID
and remove the process element from the SPA.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The first function of the link needs to configure the transaction layer
between the host and device. This is accomplished by a call to the OCXL
provider services.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
After reading and modifying the function configuration, setup the OCXL link
using the OCXL provider services. The link is released when the adapter is
unconfigured.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Use the PCI VPD services to support reading the VPD data of the underlying
adapter.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The AFU should be enabled following a successful configuration and disabled
near the end of the cleanup path.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Once the context is started, the assigned MMIO space can be mapped and
unmapped. Provide means to map and unmap the context MMIO space.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Once the adapter context is created, it needs to be started by assigning the
MMIO space for the context and by enabling the process element in the
link. This commit adds the skeleton for starting the context and assigns the
context specific MMIO space. Master contexts have access to the global MMIO
space while the rest have access to the context specific space.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
When the AFU is configured, the global and per process MMIO regions are
presented by the configuration space. Save these regions and map the global
MMIO region that is used to access all of the control and provisioning data in
the AFU.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
On a PERST, the AFU image can be reloaded or left intact. Provide means to set
this image reload policy.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Provide means to obtain the process element of an adapter context as well as
locate an adapter context by file.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Allocate a file descriptor for an adapter context when requested. In order to
allocate inodes for the file descriptors, a pseudo filesystem is created and
used.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
A range of PASIDs are used as identifiers for the adapter contexts. These
contexts may be destroyed and created randomly. Use an IDR to keep track of
contexts that are in use and assign a unique identifier to new ones.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Add support to create and release the adapter contexts for OCXL and provide
means to specify certain contexts as a master.
The existing cxlflash core has a design requirement that each host will have a
single host context available by default. To satisfy this requirement, one
host adapter context is created when the hardware AFU is initialized. This is
returned by the get_context() fop.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Per the OCXL specification, the maximum PASID supported by the AFU is
indicated by a field within the configuration space. Similar to acTags,
implementations can choose to use any sub-range of PASID within their assigned
range. For cxlflash, the entire range is used.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The OCXL specification supports distributing acTags amongst different AFUs and
functions on the link. As cxlflash devices are expected to only support a
single AFU per function, the entire range that was assigned to the function is
also assigned to the AFU.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The host AFU configuration is read on the initialization path to identify the
features and configuration of the AFU. This data is cached for use in later
configuration steps.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The OCXL specification supports distributing acTags amongst different AFUs and
functions on the link. The platform-specific acTag range for the link is
obtained using the OCXL provider services and then assigned to the host
function based on implementation.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Per the OCXL specification, the underlying host can have multiple AFUs per
function with each function supporting its own configuration. The host
function configuration is read on the initialization path to evaluate the
number of functions present and identify the features and configuration of the
functions present. This data is cached for use in later configuration
steps. Note that for the OCXL hardware supported by the cxlflash driver, only
one AFU per function is expected.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
When an adapter is initialized, transport specific configuration and MMIO
mapping details need to be saved. For CXL, this data is managed by the
underlying kernel module. To maintain a separation between the cxlflash core
and underlying transports, introduce a new structure to store data specific to
the OCXL AFU.
Initially only the pointers to underlying PCI and generic devices are added to
this new structure - it will be expanded further in future commits. Services
to create and destroy this hardware AFU are added and integrated in the probe
and exit paths of the driver.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Add initial infrastructure to support a new cxlflash transport, OCXL.
Claim a dependency on OCXL and add a new file, ocxl_hw.c, which will host the
backend routines that are specific to OCXL.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Checkpatch throws a warning when the argument identifier names are not
included in the function definitions.
To avoid these warnings, argument identifiers are added in the existing
function definitions.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The SISLite specification originally defined the context control register with
a single field of bits to represent the LISN and also stipulated that the
register reset value be 0. The cxlflash driver took advantage of this when
programming the LISN for the master contexts via an unconditional write - no
other bits were preserved.
When unmap support was added, SISLite was updated to define bit 0 of the
context control register as a way for the AFU to notify the context owner that
unmap operations were supported. Thus the assumptions under which the register
is setup changed and the existing unconditional write is clobbering the unmap
state for master contexts. This is presently not an issue due to the order in
which the context control register is programmed in relation to the unmap bit
being queried but should be addressed to avoid a future regression in the
event this code is moved elsewhere.
To remedy this issue, preserve the bits when programming the LISN field in the
context control register. Since the LISN will now be programmed using a read
value, assert that the initial state of the LISN field is as described in
SISLite (0).
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The number of interrupts requested for user contexts are stored in the context
specific structures and utilized to manage the interrupts. For the master
contexts, this number is only used once and therefore not saved.
To prepare for future commits where the number of interrupts will be required
in more than one place, preserve the value in the master context structure.
[mkp: typo in comment]
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
As staging to support future accelerator transports, add a shim layer
such that the underlying services the cxlflash driver requires can be
conditional upon the accelerator infrastructure.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Adapter context creation can return either NULL or an error pointer.
Updating the check condition to reflect this.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
