aboutsummaryrefslogtreecommitdiffstats
path: root/include/misc/cxllib.h
blob: e5aa29f019a6b36b395eab97188c27752998d46a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
/*
 * Copyright 2017 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_CXLLIB_H
#define _MISC_CXLLIB_H

#include <linux/pci.h>
#include <asm/reg.h>

/*
 * cxl driver exports a in-kernel 'library' API which can be called by
 * other drivers to help interacting with an IBM XSL.
 */

/*
 * tells whether capi is supported on the PCIe slot where the
 * device is seated
 *
 * Input:
 *	dev: device whose slot needs to be checked
 *	flags: 0 for the time being
 */
bool cxllib_slot_is_supported(struct pci_dev *dev, unsigned long flags);


/*
 * Returns the configuration parameters to be used by the XSL or device
 *
 * Input:
 *	dev: device, used to find PHB
 * Output:
 *	struct cxllib_xsl_config:
 *		version
 *		capi BAR address, i.e. 0x2000000000000-0x2FFFFFFFFFFFF
 *		capi BAR size
 *		data send control (XSL_DSNCTL)
 *		dummy read address (XSL_DRA)
 */
#define CXL_XSL_CONFIG_VERSION1		1
struct cxllib_xsl_config {
	u32	version;     /* format version for register encoding */
	u32	log_bar_size;/* log size of the capi_window */
	u64	bar_addr;    /* address of the start of capi window */
	u64	dsnctl;      /* matches definition of XSL_DSNCTL */
	u64	dra;         /* real address that can be used for dummy read */
};

int cxllib_get_xsl_config(struct pci_dev *dev, struct cxllib_xsl_config *cfg);


/*
 * Activate capi for the pci host bridge associated with the device.
 * Can be extended to deactivate once we know how to do it.
 * Device must be ready to accept messages from the CAPP unit and
 * respond accordingly (TLB invalidates, ...)
 *
 * PHB is switched to capi mode through calls to skiboot.
 * CAPP snooping is activated
 *
 * Input:
 *	dev: device whose PHB should switch mode
 *	mode: mode to switch to i.e. CAPI or PCI
 *	flags: options related to the mode
 */
enum cxllib_mode {
	CXL_MODE_CXL,
	CXL_MODE_PCI,
};

#define CXL_MODE_NO_DMA       0
#define CXL_MODE_DMA_TVT0     1
#define CXL_MODE_DMA_TVT1     2

int cxllib_switch_phb_mode(struct pci_dev *dev, enum cxllib_mode mode,
			unsigned long flags);


/*
 * Set the device for capi DMA.
 * Define its dma_ops and dma offset so that allocations will be using TVT#1
 *
 * Input:
 *	dev: device to set
 *	flags: options. CXL_MODE_DMA_TVT1 should be used
 */
int cxllib_set_device_dma(struct pci_dev *dev, unsigned long flags);


/*
 * Get the Process Element structure for the given thread
 *
 * Input:
 *    task: task_struct for the context of the translation
 *    translation_mode: whether addresses should be translated
 * Output:
 *    attr: attributes to fill up the Process Element structure from CAIA
 */
struct cxllib_pe_attributes {
	u64 sr;
	u32 lpid;
	u32 tid;
	u32 pid;
};
#define CXL_TRANSLATED_MODE 0
#define CXL_REAL_MODE 1

int cxllib_get_PE_attributes(struct task_struct *task,
	     unsigned long translation_mode, struct cxllib_pe_attributes *attr);


/*
 * Handle memory fault.
 * Fault in all the pages of the specified buffer for the permissions
 * provided in ‘flags’
 *
 * Shouldn't be called from interrupt context
 *
 * Input:
 *	mm: struct mm for the thread faulting the pages
 *	addr: base address of the buffer to page in
 *	size: size of the buffer to page in
 *	flags: permission requested (DSISR_ISSTORE...)
 */
int cxllib_handle_fault(struct mm_struct *mm, u64 addr, u64 size, u64 flags);


#endif /* _MISC_CXLLIB_H */

Privacy Policy