337 lines
13 KiB
C
337 lines
13 KiB
C
/*
|
|
* Copyright 2015 IBM Corp.
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version
|
|
* 2 of the License, or (at your option) any later version.
|
|
*/
|
|
|
|
#ifndef _MISC_CXL_H
|
|
#define _MISC_CXL_H
|
|
|
|
#include <linux/pci.h>
|
|
#include <linux/poll.h>
|
|
#include <linux/interrupt.h>
|
|
#include <uapi/misc/cxl.h>
|
|
|
|
/*
|
|
* This documents the in kernel API for driver to use CXL. It allows kernel
|
|
* drivers to bind to AFUs using an AFU configuration record exposed as a PCI
|
|
* configuration record.
|
|
*
|
|
* This API enables control over AFU and contexts which can't be part of the
|
|
* generic PCI API. This API is agnostic to the actual AFU.
|
|
*/
|
|
|
|
#define CXL_SLOT_FLAG_DMA 0x1
|
|
|
|
/*
|
|
* Checks if the given card is in a cxl capable slot. Pass CXL_SLOT_FLAG_DMA if
|
|
* the card requires CAPP DMA mode to also check if the system supports it.
|
|
* This is intended to be used by bi-modal devices to determine if they can use
|
|
* cxl mode or if they should continue running in PCI mode.
|
|
*
|
|
* Note that this only checks if the slot is cxl capable - it does not
|
|
* currently check if the CAPP is currently available for chips where it can be
|
|
* assigned to different PHBs on a first come first serve basis (i.e. P8)
|
|
*/
|
|
bool cxl_slot_is_supported(struct pci_dev *dev, int flags);
|
|
|
|
|
|
#define CXL_BIMODE_CXL 1
|
|
#define CXL_BIMODE_PCI 2
|
|
|
|
/*
|
|
* Check the mode that the given bi-modal CXL adapter is currently in and
|
|
* change it if necessary. This does not apply to AFU drivers.
|
|
*
|
|
* If the mode matches the requested mode this function will return 0 - if the
|
|
* driver was expecting the generic CXL driver to have bound to the adapter and
|
|
* it gets this return value it should fail the probe function to give the CXL
|
|
* driver a chance to probe it.
|
|
*
|
|
* If the mode does not match it will start a background task to unplug the
|
|
* device from Linux and switch its mode, and will return -EBUSY. At this
|
|
* point the calling driver should make sure it has released the device and
|
|
* fail its probe function.
|
|
*
|
|
* The offset of the CXL VSEC can be provided to this function. If 0 is passed,
|
|
* this function will search for a CXL VSEC with ID 0x1280 and return -ENODEV
|
|
* if it is not found.
|
|
*/
|
|
#ifdef CONFIG_CXL_BIMODAL
|
|
int cxl_check_and_switch_mode(struct pci_dev *dev, int mode, int vsec);
|
|
#endif
|
|
|
|
/* Get the AFU associated with a pci_dev */
|
|
struct cxl_afu *cxl_pci_to_afu(struct pci_dev *dev);
|
|
|
|
/* Get the AFU conf record number associated with a pci_dev */
|
|
unsigned int cxl_pci_to_cfg_record(struct pci_dev *dev);
|
|
|
|
|
|
/*
|
|
* Context lifetime overview:
|
|
*
|
|
* An AFU context may be inited and then started and stoppped multiple times
|
|
* before it's released. ie.
|
|
* - cxl_dev_context_init()
|
|
* - cxl_start_context()
|
|
* - cxl_stop_context()
|
|
* - cxl_start_context()
|
|
* - cxl_stop_context()
|
|
* ...repeat...
|
|
* - cxl_release_context()
|
|
* Once released, a context can't be started again.
|
|
*
|
|
* One context is inited by the cxl driver for every pci_dev. This is to be
|
|
* used as a default kernel context. cxl_get_context() will get this
|
|
* context. This context will be released by PCI hot unplug, so doesn't need to
|
|
* be released explicitly by drivers.
|
|
*
|
|
* Additional kernel contexts may be inited using cxl_dev_context_init().
|
|
* These must be released using cxl_context_detach().
|
|
*
|
|
* Once a context has been inited, IRQs may be configured. Firstly these IRQs
|
|
* must be allocated (cxl_allocate_afu_irqs()), then individually mapped to
|
|
* specific handlers (cxl_map_afu_irq()).
|
|
*
|
|
* These IRQs can be unmapped (cxl_unmap_afu_irq()) and finally released
|
|
* (cxl_free_afu_irqs()).
|
|
*
|
|
* The AFU can be reset (cxl_afu_reset()). This will cause the PSL/AFU
|
|
* hardware to lose track of all contexts. It's upto the caller of
|
|
* cxl_afu_reset() to restart these contexts.
|
|
*/
|
|
|
|
/*
|
|
* On pci_enabled_device(), the cxl driver will init a single cxl context for
|
|
* use by the driver. It doesn't start this context (as that will likely
|
|
* generate DMA traffic for most AFUs).
|
|
*
|
|
* This gets the default context associated with this pci_dev. This context
|
|
* doesn't need to be released as this will be done by the PCI subsystem on hot
|
|
* unplug.
|
|
*/
|
|
struct cxl_context *cxl_get_context(struct pci_dev *dev);
|
|
/*
|
|
* Allocate and initalise a context associated with a AFU PCI device. This
|
|
* doesn't start the context in the AFU.
|
|
*/
|
|
struct cxl_context *cxl_dev_context_init(struct pci_dev *dev);
|
|
/*
|
|
* Release and free a context. Context should be stopped before calling.
|
|
*/
|
|
int cxl_release_context(struct cxl_context *ctx);
|
|
|
|
/*
|
|
* Set and get private data associated with a context. Allows drivers to have a
|
|
* back pointer to some useful structure.
|
|
*/
|
|
int cxl_set_priv(struct cxl_context *ctx, void *priv);
|
|
void *cxl_get_priv(struct cxl_context *ctx);
|
|
|
|
/*
|
|
* Allocate AFU interrupts for this context. num=0 will allocate the default
|
|
* for this AFU as given in the AFU descriptor. This number doesn't include the
|
|
* interrupt 0 (CAIA defines AFU IRQ 0 for page faults). Each interrupt to be
|
|
* used must map a handler with cxl_map_afu_irq.
|
|
*/
|
|
int cxl_allocate_afu_irqs(struct cxl_context *cxl, int num);
|
|
/* Free allocated interrupts */
|
|
void cxl_free_afu_irqs(struct cxl_context *cxl);
|
|
|
|
/*
|
|
* Map a handler for an AFU interrupt associated with a particular context. AFU
|
|
* IRQS numbers start from 1 (CAIA defines AFU IRQ 0 for page faults). cookie
|
|
* is private data is that will be provided to the interrupt handler.
|
|
*/
|
|
int cxl_map_afu_irq(struct cxl_context *cxl, int num,
|
|
irq_handler_t handler, void *cookie, char *name);
|
|
/* unmap mapped IRQ handlers */
|
|
void cxl_unmap_afu_irq(struct cxl_context *cxl, int num, void *cookie);
|
|
|
|
/*
|
|
* Start work on the AFU. This starts an cxl context and associates it with a
|
|
* task. task == NULL will make it a kernel context.
|
|
*/
|
|
int cxl_start_context(struct cxl_context *ctx, u64 wed,
|
|
struct task_struct *task);
|
|
/*
|
|
* Stop a context and remove it from the PSL
|
|
*/
|
|
int cxl_stop_context(struct cxl_context *ctx);
|
|
|
|
/* Reset the AFU */
|
|
int cxl_afu_reset(struct cxl_context *ctx);
|
|
|
|
/*
|
|
* Set a context as a master context.
|
|
* This sets the default problem space area mapped as the full space, rather
|
|
* than just the per context area (for slaves).
|
|
*/
|
|
void cxl_set_master(struct cxl_context *ctx);
|
|
|
|
/*
|
|
* Sets the context to use real mode memory accesses to operate with
|
|
* translation disabled. Note that this only makes sense for kernel contexts
|
|
* under bare metal, and will not work with virtualisation. May only be
|
|
* performed on stopped contexts.
|
|
*/
|
|
int cxl_set_translation_mode(struct cxl_context *ctx, bool real_mode);
|
|
|
|
/*
|
|
* Map and unmap the AFU Problem Space area. The amount and location mapped
|
|
* depends on if this context is a master or slave.
|
|
*/
|
|
void __iomem *cxl_psa_map(struct cxl_context *ctx);
|
|
void cxl_psa_unmap(void __iomem *addr);
|
|
|
|
/* Get the process element for this context */
|
|
int cxl_process_element(struct cxl_context *ctx);
|
|
|
|
/*
|
|
* Limit the number of interrupts that a single context can allocate via
|
|
* cxl_start_work. If using the api with a real phb, this may be used to
|
|
* request that additional default contexts be created when allocating
|
|
* interrupts via pci_enable_msix_range. These will be set to the same running
|
|
* state as the default context, and if that is running it will reuse the
|
|
* parameters previously passed to cxl_start_context for the default context.
|
|
*/
|
|
int cxl_set_max_irqs_per_process(struct pci_dev *dev, int irqs);
|
|
int cxl_get_max_irqs_per_process(struct pci_dev *dev);
|
|
|
|
/*
|
|
* Use to simultaneously iterate over hardware interrupt numbers, contexts and
|
|
* afu interrupt numbers allocated for the device via pci_enable_msix_range and
|
|
* is a useful convenience function when working with hardware that has
|
|
* limitations on the number of interrupts per process. *ctx and *afu_irq
|
|
* should be NULL and 0 to start the iteration.
|
|
*/
|
|
int cxl_next_msi_hwirq(struct pci_dev *pdev, struct cxl_context **ctx, int *afu_irq);
|
|
|
|
/*
|
|
* These calls allow drivers to create their own file descriptors and make them
|
|
* identical to the cxl file descriptor user API. An example use case:
|
|
*
|
|
* struct file_operations cxl_my_fops = {};
|
|
* ......
|
|
* // Init the context
|
|
* ctx = cxl_dev_context_init(dev);
|
|
* if (IS_ERR(ctx))
|
|
* return PTR_ERR(ctx);
|
|
* // Create and attach a new file descriptor to my file ops
|
|
* file = cxl_get_fd(ctx, &cxl_my_fops, &fd);
|
|
* // Start context
|
|
* rc = cxl_start_work(ctx, &work.work);
|
|
* if (rc) {
|
|
* fput(file);
|
|
* put_unused_fd(fd);
|
|
* return -ENODEV;
|
|
* }
|
|
* // No error paths after installing the fd
|
|
* fd_install(fd, file);
|
|
* return fd;
|
|
*
|
|
* This inits a context, and gets a file descriptor and associates some file
|
|
* ops to that file descriptor. If the file ops are blank, the cxl driver will
|
|
* fill them in with the default ones that mimic the standard user API. Once
|
|
* completed, the file descriptor can be installed. Once the file descriptor is
|
|
* installed, it's visible to the user so no errors must occur past this point.
|
|
*
|
|
* If cxl_fd_release() file op call is installed, the context will be stopped
|
|
* and released when the fd is released. Hence the driver won't need to manage
|
|
* this itself.
|
|
*/
|
|
|
|
/*
|
|
* Take a context and associate it with my file ops. Returns the associated
|
|
* file and file descriptor. Any file ops which are blank are filled in by the
|
|
* cxl driver with the default ops to mimic the standard API.
|
|
*/
|
|
struct file *cxl_get_fd(struct cxl_context *ctx, struct file_operations *fops,
|
|
int *fd);
|
|
/* Get the context associated with this file */
|
|
struct cxl_context *cxl_fops_get_context(struct file *file);
|
|
/*
|
|
* Start a context associated a struct cxl_ioctl_start_work used by the
|
|
* standard cxl user API.
|
|
*/
|
|
int cxl_start_work(struct cxl_context *ctx,
|
|
struct cxl_ioctl_start_work *work);
|
|
/*
|
|
* Export all the existing fops so drivers can use them
|
|
*/
|
|
int cxl_fd_open(struct inode *inode, struct file *file);
|
|
int cxl_fd_release(struct inode *inode, struct file *file);
|
|
long cxl_fd_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
|
|
int cxl_fd_mmap(struct file *file, struct vm_area_struct *vm);
|
|
unsigned int cxl_fd_poll(struct file *file, struct poll_table_struct *poll);
|
|
ssize_t cxl_fd_read(struct file *file, char __user *buf, size_t count,
|
|
loff_t *off);
|
|
|
|
/*
|
|
* For EEH, a driver may want to assert a PERST will reload the same image
|
|
* from flash into the FPGA.
|
|
*
|
|
* This is a property of the entire adapter, not a single AFU, so drivers
|
|
* should set this property with care!
|
|
*/
|
|
void cxl_perst_reloads_same_image(struct cxl_afu *afu,
|
|
bool perst_reloads_same_image);
|
|
|
|
/*
|
|
* Read the VPD for the card where the AFU resides
|
|
*/
|
|
ssize_t cxl_read_adapter_vpd(struct pci_dev *dev, void *buf, size_t count);
|
|
|
|
/*
|
|
* AFU driver ops allow an AFU driver to create their own events to pass to
|
|
* userspace through the file descriptor as a simpler alternative to overriding
|
|
* the read() and poll() calls that works with the generic cxl events. These
|
|
* events are given priority over the generic cxl events, so they will be
|
|
* delivered first if multiple types of events are pending.
|
|
*
|
|
* The AFU driver must call cxl_context_events_pending() to notify the cxl
|
|
* driver that new events are ready to be delivered for a specific context.
|
|
* cxl_context_events_pending() will adjust the current count of AFU driver
|
|
* events for this context, and wake up anyone waiting on the context wait
|
|
* queue.
|
|
*
|
|
* The cxl driver will then call fetch_event() to get a structure defining
|
|
* the size and address of the driver specific event data. The cxl driver
|
|
* will build a cxl header with type and process_element fields filled in,
|
|
* and header.size set to sizeof(struct cxl_event_header) + data_size.
|
|
* The total size of the event is limited to CXL_READ_MIN_SIZE (4K).
|
|
*
|
|
* fetch_event() is called with a spin lock held, so it must not sleep.
|
|
*
|
|
* The cxl driver will then deliver the event to userspace, and finally
|
|
* call event_delivered() to return the status of the operation, identified
|
|
* by cxl context and AFU driver event data pointers.
|
|
* 0 Success
|
|
* -EFAULT copy_to_user() has failed
|
|
* -EINVAL Event data pointer is NULL, or event size is greater than
|
|
* CXL_READ_MIN_SIZE.
|
|
*/
|
|
struct cxl_afu_driver_ops {
|
|
struct cxl_event_afu_driver_reserved *(*fetch_event) (
|
|
struct cxl_context *ctx);
|
|
void (*event_delivered) (struct cxl_context *ctx,
|
|
struct cxl_event_afu_driver_reserved *event,
|
|
int rc);
|
|
};
|
|
|
|
/*
|
|
* Associate the above driver ops with a specific context.
|
|
* Reset the current count of AFU driver events.
|
|
*/
|
|
void cxl_set_driver_ops(struct cxl_context *ctx,
|
|
struct cxl_afu_driver_ops *ops);
|
|
|
|
/* Notify cxl driver that new events are ready to be delivered for context */
|
|
void cxl_context_events_pending(struct cxl_context *ctx,
|
|
unsigned int new_events);
|
|
|
|
#endif /* _MISC_CXL_H */
|