Commit | Line | Data |
---|---|---|
6f7f0b3d MN |
1 | /* |
2 | * Copyright 2015 IBM Corp. | |
3 | * | |
4 | * This program is free software; you can redistribute it and/or | |
5 | * modify it under the terms of the GNU General Public License | |
6 | * as published by the Free Software Foundation; either version | |
7 | * 2 of the License, or (at your option) any later version. | |
8 | */ | |
9 | ||
10 | #ifndef _MISC_CXL_H | |
11 | #define _MISC_CXL_H | |
12 | ||
13 | #include <linux/pci.h> | |
14 | #include <linux/poll.h> | |
15 | #include <linux/interrupt.h> | |
16 | #include <uapi/misc/cxl.h> | |
17 | ||
18 | /* | |
19 | * This documents the in kernel API for driver to use CXL. It allows kernel | |
20 | * drivers to bind to AFUs using an AFU configuration record exposed as a PCI | |
21 | * configuration record. | |
22 | * | |
23 | * This API enables control over AFU and contexts which can't be part of the | |
24 | * generic PCI API. This API is agnostic to the actual AFU. | |
25 | */ | |
26 | ||
27 | /* Get the AFU associated with a pci_dev */ | |
28 | struct cxl_afu *cxl_pci_to_afu(struct pci_dev *dev); | |
29 | ||
30 | /* Get the AFU conf record number associated with a pci_dev */ | |
31 | unsigned int cxl_pci_to_cfg_record(struct pci_dev *dev); | |
32 | ||
6f7f0b3d MN |
33 | |
34 | /* | |
35 | * Context lifetime overview: | |
36 | * | |
37 | * An AFU context may be inited and then started and stoppped multiple times | |
38 | * before it's released. ie. | |
39 | * - cxl_dev_context_init() | |
40 | * - cxl_start_context() | |
41 | * - cxl_stop_context() | |
42 | * - cxl_start_context() | |
43 | * - cxl_stop_context() | |
44 | * ...repeat... | |
45 | * - cxl_release_context() | |
46 | * Once released, a context can't be started again. | |
47 | * | |
48 | * One context is inited by the cxl driver for every pci_dev. This is to be | |
49 | * used as a default kernel context. cxl_get_context() will get this | |
50 | * context. This context will be released by PCI hot unplug, so doesn't need to | |
51 | * be released explicitly by drivers. | |
52 | * | |
53 | * Additional kernel contexts may be inited using cxl_dev_context_init(). | |
54 | * These must be released using cxl_context_detach(). | |
55 | * | |
56 | * Once a context has been inited, IRQs may be configured. Firstly these IRQs | |
57 | * must be allocated (cxl_allocate_afu_irqs()), then individually mapped to | |
58 | * specific handlers (cxl_map_afu_irq()). | |
59 | * | |
60 | * These IRQs can be unmapped (cxl_unmap_afu_irq()) and finally released | |
61 | * (cxl_free_afu_irqs()). | |
62 | * | |
63 | * The AFU can be reset (cxl_afu_reset()). This will cause the PSL/AFU | |
64 | * hardware to lose track of all contexts. It's upto the caller of | |
65 | * cxl_afu_reset() to restart these contexts. | |
66 | */ | |
67 | ||
68 | /* | |
69 | * On pci_enabled_device(), the cxl driver will init a single cxl context for | |
70 | * use by the driver. It doesn't start this context (as that will likely | |
71 | * generate DMA traffic for most AFUs). | |
72 | * | |
73 | * This gets the default context associated with this pci_dev. This context | |
74 | * doesn't need to be released as this will be done by the PCI subsystem on hot | |
75 | * unplug. | |
76 | */ | |
77 | struct cxl_context *cxl_get_context(struct pci_dev *dev); | |
78 | /* | |
79 | * Allocate and initalise a context associated with a AFU PCI device. This | |
80 | * doesn't start the context in the AFU. | |
81 | */ | |
82 | struct cxl_context *cxl_dev_context_init(struct pci_dev *dev); | |
83 | /* | |
84 | * Release and free a context. Context should be stopped before calling. | |
85 | */ | |
86 | int cxl_release_context(struct cxl_context *ctx); | |
87 | ||
88 | /* | |
89 | * Allocate AFU interrupts for this context. num=0 will allocate the default | |
90 | * for this AFU as given in the AFU descriptor. This number doesn't include the | |
91 | * interrupt 0 (CAIA defines AFU IRQ 0 for page faults). Each interrupt to be | |
92 | * used must map a handler with cxl_map_afu_irq. | |
93 | */ | |
94 | int cxl_allocate_afu_irqs(struct cxl_context *cxl, int num); | |
95 | /* Free allocated interrupts */ | |
96 | void cxl_free_afu_irqs(struct cxl_context *cxl); | |
97 | ||
98 | /* | |
99 | * Map a handler for an AFU interrupt associated with a particular context. AFU | |
100 | * IRQS numbers start from 1 (CAIA defines AFU IRQ 0 for page faults). cookie | |
101 | * is private data is that will be provided to the interrupt handler. | |
102 | */ | |
103 | int cxl_map_afu_irq(struct cxl_context *cxl, int num, | |
104 | irq_handler_t handler, void *cookie, char *name); | |
105 | /* unmap mapped IRQ handlers */ | |
106 | void cxl_unmap_afu_irq(struct cxl_context *cxl, int num, void *cookie); | |
107 | ||
108 | /* | |
109 | * Start work on the AFU. This starts an cxl context and associates it with a | |
110 | * task. task == NULL will make it a kernel context. | |
111 | */ | |
112 | int cxl_start_context(struct cxl_context *ctx, u64 wed, | |
113 | struct task_struct *task); | |
114 | /* | |
115 | * Stop a context and remove it from the PSL | |
116 | */ | |
117 | int cxl_stop_context(struct cxl_context *ctx); | |
118 | ||
119 | /* Reset the AFU */ | |
120 | int cxl_afu_reset(struct cxl_context *ctx); | |
121 | ||
122 | /* | |
123 | * Set a context as a master context. | |
124 | * This sets the default problem space area mapped as the full space, rather | |
125 | * than just the per context area (for slaves). | |
126 | */ | |
127 | void cxl_set_master(struct cxl_context *ctx); | |
128 | ||
129 | /* | |
130 | * Map and unmap the AFU Problem Space area. The amount and location mapped | |
131 | * depends on if this context is a master or slave. | |
132 | */ | |
133 | void __iomem *cxl_psa_map(struct cxl_context *ctx); | |
134 | void cxl_psa_unmap(void __iomem *addr); | |
135 | ||
136 | /* Get the process element for this context */ | |
137 | int cxl_process_element(struct cxl_context *ctx); | |
138 | ||
139 | ||
140 | /* | |
141 | * These calls allow drivers to create their own file descriptors and make them | |
142 | * identical to the cxl file descriptor user API. An example use case: | |
143 | * | |
144 | * struct file_operations cxl_my_fops = {}; | |
145 | * ...... | |
146 | * // Init the context | |
147 | * ctx = cxl_dev_context_init(dev); | |
148 | * if (IS_ERR(ctx)) | |
149 | * return PTR_ERR(ctx); | |
150 | * // Create and attach a new file descriptor to my file ops | |
151 | * file = cxl_get_fd(ctx, &cxl_my_fops, &fd); | |
152 | * // Start context | |
153 | * rc = cxl_start_work(ctx, &work.work); | |
154 | * if (rc) { | |
155 | * fput(file); | |
156 | * put_unused_fd(fd); | |
157 | * return -ENODEV; | |
158 | * } | |
159 | * // No error paths after installing the fd | |
160 | * fd_install(fd, file); | |
161 | * return fd; | |
162 | * | |
163 | * This inits a context, and gets a file descriptor and associates some file | |
164 | * ops to that file descriptor. If the file ops are blank, the cxl driver will | |
165 | * fill them in with the default ones that mimic the standard user API. Once | |
166 | * completed, the file descriptor can be installed. Once the file descriptor is | |
167 | * installed, it's visible to the user so no errors must occur past this point. | |
168 | * | |
169 | * If cxl_fd_release() file op call is installed, the context will be stopped | |
170 | * and released when the fd is released. Hence the driver won't need to manage | |
171 | * this itself. | |
172 | */ | |
173 | ||
174 | /* | |
175 | * Take a context and associate it with my file ops. Returns the associated | |
176 | * file and file descriptor. Any file ops which are blank are filled in by the | |
177 | * cxl driver with the default ops to mimic the standard API. | |
178 | */ | |
179 | struct file *cxl_get_fd(struct cxl_context *ctx, struct file_operations *fops, | |
180 | int *fd); | |
181 | /* Get the context associated with this file */ | |
182 | struct cxl_context *cxl_fops_get_context(struct file *file); | |
183 | /* | |
184 | * Start a context associated a struct cxl_ioctl_start_work used by the | |
185 | * standard cxl user API. | |
186 | */ | |
187 | int cxl_start_work(struct cxl_context *ctx, | |
188 | struct cxl_ioctl_start_work *work); | |
189 | /* | |
190 | * Export all the existing fops so drivers can use them | |
191 | */ | |
192 | int cxl_fd_open(struct inode *inode, struct file *file); | |
193 | int cxl_fd_release(struct inode *inode, struct file *file); | |
194 | long cxl_fd_ioctl(struct file *file, unsigned int cmd, unsigned long arg); | |
195 | int cxl_fd_mmap(struct file *file, struct vm_area_struct *vm); | |
196 | unsigned int cxl_fd_poll(struct file *file, struct poll_table_struct *poll); | |
197 | ssize_t cxl_fd_read(struct file *file, char __user *buf, size_t count, | |
198 | loff_t *off); | |
199 | ||
13e68d8b DA |
200 | /* |
201 | * For EEH, a driver may want to assert a PERST will reload the same image | |
202 | * from flash into the FPGA. | |
203 | * | |
204 | * This is a property of the entire adapter, not a single AFU, so drivers | |
205 | * should set this property with care! | |
206 | */ | |
207 | void cxl_perst_reloads_same_image(struct cxl_afu *afu, | |
208 | bool perst_reloads_same_image); | |
209 | ||
d601ea91 FB |
210 | /* |
211 | * Read the VPD for the card where the AFU resides | |
212 | */ | |
213 | ssize_t cxl_read_adapter_vpd(struct pci_dev *dev, void *buf, size_t count); | |
214 | ||
6f7f0b3d | 215 | #endif /* _MISC_CXL_H */ |