1 | /* SPDX-License-Identifier: GPL-2.0-or-later */ |
2 | /* |
3 | * Copyright 2017 IBM Corp. |
4 | */ |
5 | |
6 | #ifndef _MISC_CXLLIB_H |
7 | #define _MISC_CXLLIB_H |
8 | |
9 | #include <linux/pci.h> |
10 | #include <asm/reg.h> |
11 | |
12 | /* |
13 | * cxl driver exports a in-kernel 'library' API which can be called by |
14 | * other drivers to help interacting with an IBM XSL. |
15 | */ |
16 | |
17 | /* |
18 | * tells whether capi is supported on the PCIe slot where the |
19 | * device is seated |
20 | * |
21 | * Input: |
22 | * dev: device whose slot needs to be checked |
23 | * flags: 0 for the time being |
24 | */ |
25 | bool cxllib_slot_is_supported(struct pci_dev *dev, unsigned long flags); |
26 | |
27 | |
28 | /* |
29 | * Returns the configuration parameters to be used by the XSL or device |
30 | * |
31 | * Input: |
32 | * dev: device, used to find PHB |
33 | * Output: |
34 | * struct cxllib_xsl_config: |
35 | * version |
36 | * capi BAR address, i.e. 0x2000000000000-0x2FFFFFFFFFFFF |
37 | * capi BAR size |
38 | * data send control (XSL_DSNCTL) |
39 | * dummy read address (XSL_DRA) |
40 | */ |
41 | #define CXL_XSL_CONFIG_VERSION1 1 |
42 | struct cxllib_xsl_config { |
43 | u32 version; /* format version for register encoding */ |
44 | u32 log_bar_size;/* log size of the capi_window */ |
45 | u64 bar_addr; /* address of the start of capi window */ |
46 | u64 dsnctl; /* matches definition of XSL_DSNCTL */ |
47 | u64 dra; /* real address that can be used for dummy read */ |
48 | }; |
49 | |
50 | int cxllib_get_xsl_config(struct pci_dev *dev, struct cxllib_xsl_config *cfg); |
51 | |
52 | |
53 | /* |
54 | * Activate capi for the pci host bridge associated with the device. |
55 | * Can be extended to deactivate once we know how to do it. |
56 | * Device must be ready to accept messages from the CAPP unit and |
57 | * respond accordingly (TLB invalidates, ...) |
58 | * |
59 | * PHB is switched to capi mode through calls to skiboot. |
60 | * CAPP snooping is activated |
61 | * |
62 | * Input: |
63 | * dev: device whose PHB should switch mode |
64 | * mode: mode to switch to i.e. CAPI or PCI |
65 | * flags: options related to the mode |
66 | */ |
67 | enum cxllib_mode { |
68 | CXL_MODE_CXL, |
69 | CXL_MODE_PCI, |
70 | }; |
71 | |
72 | #define CXL_MODE_NO_DMA 0 |
73 | #define CXL_MODE_DMA_TVT0 1 |
74 | #define CXL_MODE_DMA_TVT1 2 |
75 | |
76 | int cxllib_switch_phb_mode(struct pci_dev *dev, enum cxllib_mode mode, |
77 | unsigned long flags); |
78 | |
79 | |
80 | /* |
81 | * Set the device for capi DMA. |
82 | * Define its dma_ops and dma offset so that allocations will be using TVT#1 |
83 | * |
84 | * Input: |
85 | * dev: device to set |
86 | * flags: options. CXL_MODE_DMA_TVT1 should be used |
87 | */ |
88 | int cxllib_set_device_dma(struct pci_dev *dev, unsigned long flags); |
89 | |
90 | |
91 | /* |
92 | * Get the Process Element structure for the given thread |
93 | * |
94 | * Input: |
95 | * task: task_struct for the context of the translation |
96 | * translation_mode: whether addresses should be translated |
97 | * Output: |
98 | * attr: attributes to fill up the Process Element structure from CAIA |
99 | */ |
100 | struct cxllib_pe_attributes { |
101 | u64 sr; |
102 | u32 lpid; |
103 | u32 tid; |
104 | u32 pid; |
105 | }; |
106 | #define CXL_TRANSLATED_MODE 0 |
107 | #define CXL_REAL_MODE 1 |
108 | |
109 | int cxllib_get_PE_attributes(struct task_struct *task, |
110 | unsigned long translation_mode, struct cxllib_pe_attributes *attr); |
111 | |
112 | |
113 | /* |
114 | * Handle memory fault. |
115 | * Fault in all the pages of the specified buffer for the permissions |
116 | * provided in ‘flags’ |
117 | * |
118 | * Shouldn't be called from interrupt context |
119 | * |
120 | * Input: |
121 | * mm: struct mm for the thread faulting the pages |
122 | * addr: base address of the buffer to page in |
123 | * size: size of the buffer to page in |
124 | * flags: permission requested (DSISR_ISSTORE...) |
125 | */ |
126 | int cxllib_handle_fault(struct mm_struct *mm, u64 addr, u64 size, u64 flags); |
127 | |
128 | |
129 | #endif /* _MISC_CXLLIB_H */ |
130 | |