1// SPDX-License-Identifier: GPL-2.0+
  2// Copyright 2017 IBM Corp.
  3#ifndef _MISC_OCXL_H_
  4#define _MISC_OCXL_H_
  5
  6#include <linux/pci.h>
  7
  8/*
  9 * Opencapi drivers all need some common facilities, like parsing the
 10 * device configuration space, adding a Process Element to the Shared
 11 * Process Area, etc...
 12 *
 13 * The ocxl module provides a kernel API, to allow other drivers to
 14 * reuse common code. A bit like a in-kernel library.
 15 */
 16
 17#define OCXL_AFU_NAME_SZ      (24+1)  /* add 1 for NULL termination */
 18
 19/*
 20 * The following 2 structures are a fairly generic way of representing
 21 * the configuration data for a function and AFU, as read from the
 22 * configuration space.
 23 */
 24struct ocxl_afu_config {
 25	u8 idx;
 26	int dvsec_afu_control_pos; /* offset of AFU control DVSEC */
 27	char name[OCXL_AFU_NAME_SZ];
 28	u8 version_major;
 29	u8 version_minor;
 30	u8 afuc_type;
 31	u8 afum_type;
 32	u8 profile;
 33	u8 global_mmio_bar;     /* global MMIO area */
 34	u64 global_mmio_offset;
 35	u32 global_mmio_size;
 36	u8 pp_mmio_bar;         /* per-process MMIO area */
 37	u64 pp_mmio_offset;
 38	u32 pp_mmio_stride;
 39	u8 log_mem_size;
 40	u8 pasid_supported_log;
 41	u16 actag_supported;
 42};
 43
 44struct ocxl_fn_config {
 45	int dvsec_tl_pos;       /* offset of the Transaction Layer DVSEC */
 46	int dvsec_function_pos; /* offset of the Function DVSEC */
 47	int dvsec_afu_info_pos; /* offset of the AFU information DVSEC */
 48	s8 max_pasid_log;
 49	s8 max_afu_index;
 50};
 51
 52/*
 53 * Read the configuration space of a function and fill in a
 54 * ocxl_fn_config structure with all the function details
 55 */
 56extern int ocxl_config_read_function(struct pci_dev *dev,
 57				struct ocxl_fn_config *fn);
 58
 59/*
 60 * Check if an AFU index is valid for the given function.
 61 *
 62 * AFU indexes can be sparse, so a driver should check all indexes up
 63 * to the maximum found in the function description
 64 */
 65extern int ocxl_config_check_afu_index(struct pci_dev *dev,
 66				struct ocxl_fn_config *fn, int afu_idx);
 67
 68/*
 69 * Read the configuration space of a function for the AFU specified by
 70 * the index 'afu_idx'. Fills in a ocxl_afu_config structure
 71 */
 72extern int ocxl_config_read_afu(struct pci_dev *dev,
 73				struct ocxl_fn_config *fn,
 74				struct ocxl_afu_config *afu,
 75				u8 afu_idx);
 76
 77/*
 78 * Get the max PASID value that can be used by the function
 79 */
 80extern int ocxl_config_get_pasid_info(struct pci_dev *dev, int *count);
 81
 82/*
 83 * Tell an AFU, by writing in the configuration space, the PASIDs that
 84 * it can use. Range starts at 'pasid_base' and its size is a multiple
 85 * of 2
 86 *
 87 * 'afu_control_offset' is the offset of the AFU control DVSEC which
 88 * can be found in the function configuration
 89 */
 90extern void ocxl_config_set_afu_pasid(struct pci_dev *dev,
 91				int afu_control_offset,
 92				int pasid_base, u32 pasid_count_log);
 93
 94/*
 95 * Get the actag configuration for the function:
 96 * 'base' is the first actag value that can be used.
 97 * 'enabled' it the number of actags available, starting from base.
 98 * 'supported' is the total number of actags desired by all the AFUs
 99 *             of the function.
100 */
101extern int ocxl_config_get_actag_info(struct pci_dev *dev,
102				u16 *base, u16 *enabled, u16 *supported);
103
104/*
105 * Tell a function, by writing in the configuration space, the actags
106 * it can use.
107 *
108 * 'func_offset' is the offset of the Function DVSEC that can found in
109 * the function configuration
110 */
111extern void ocxl_config_set_actag(struct pci_dev *dev, int func_offset,
112				u32 actag_base, u32 actag_count);
113
114/*
115 * Tell an AFU, by writing in the configuration space, the actags it
116 * can use.
117 *
118 * 'afu_control_offset' is the offset of the AFU control DVSEC for the
119 * desired AFU. It can be found in the AFU configuration
120 */
121extern void ocxl_config_set_afu_actag(struct pci_dev *dev,
122				int afu_control_offset,
123				int actag_base, int actag_count);
124
125/*
126 * Enable/disable an AFU, by writing in the configuration space.
127 *
128 * 'afu_control_offset' is the offset of the AFU control DVSEC for the
129 * desired AFU. It can be found in the AFU configuration
130 */
131extern void ocxl_config_set_afu_state(struct pci_dev *dev,
132				int afu_control_offset, int enable);
133
134/*
135 * Set the Transaction Layer configuration in the configuration space.
136 * Only needed for function 0.
137 *
138 * It queries the host TL capabilities, find some common ground
139 * between the host and device, and set the Transaction Layer on both
140 * accordingly.
141 */
142extern int ocxl_config_set_TL(struct pci_dev *dev, int tl_dvsec);
143
144/*
145 * Request an AFU to terminate a PASID.
146 * Will return once the AFU has acked the request, or an error in case
147 * of timeout.
148 *
149 * The hardware can only terminate one PASID at a time, so caller must
150 * guarantee some kind of serialization.
151 *
152 * 'afu_control_offset' is the offset of the AFU control DVSEC for the
153 * desired AFU. It can be found in the AFU configuration
154 */
155extern int ocxl_config_terminate_pasid(struct pci_dev *dev,
156				int afu_control_offset, int pasid);
157
158/*
159 * Set up the opencapi link for the function.
160 *
161 * When called for the first time for a link, it sets up the Shared
162 * Process Area for the link and the interrupt handler to process
163 * translation faults.
164 *
165 * Returns a 'link handle' that should be used for further calls for
166 * the link
167 */
168extern int ocxl_link_setup(struct pci_dev *dev, int PE_mask,
169			void **link_handle);
170
171/*
172 * Remove the association between the function and its link.
173 */
174extern void ocxl_link_release(struct pci_dev *dev, void *link_handle);
175
176/*
177 * Add a Process Element to the Shared Process Area for a link.
178 * The process is defined by its PASID, pid, tid and its mm_struct.
179 *
180 * 'xsl_err_cb' is an optional callback if the driver wants to be
181 * notified when the translation fault interrupt handler detects an
182 * address error.
183 * 'xsl_err_data' is an argument passed to the above callback, if
184 * defined
185 */
186extern int ocxl_link_add_pe(void *link_handle, int pasid, u32 pidr, u32 tidr,
187		u64 amr, struct mm_struct *mm,
188		void (*xsl_err_cb)(void *data, u64 addr, u64 dsisr),
189		void *xsl_err_data);
190
191/*
192 * Remove a Process Element from the Shared Process Area for a link
193 */
194extern int ocxl_link_remove_pe(void *link_handle, int pasid);
195
196/*
197 * Allocate an AFU interrupt associated to the link.
198 *
199 * 'hw_irq' is the hardware interrupt number
200 * 'obj_handle' is the 64-bit object handle to be passed to the AFU to
201 * trigger the interrupt.
202 * On P9, 'obj_handle' is an address, which, if written, triggers the
203 * interrupt. It is an MMIO address which needs to be remapped (one
204 * page).
205 */
206extern int ocxl_link_irq_alloc(void *link_handle, int *hw_irq,
207			u64 *obj_handle);
208
209/*
210 * Free a previously allocated AFU interrupt
211 */
212extern void ocxl_link_free_irq(void *link_handle, int hw_irq);
213
214#endif /* _MISC_OCXL_H_ */