1 /***************************************************************************
2 * Copyright (c) 2024 Microsoft Corporation
3 *
4 * This program and the accompanying materials are made available under the
5 * terms of the MIT License which is available at
6 * https://opensource.org/licenses/MIT.
7 *
8 * SPDX-License-Identifier: MIT
9 **************************************************************************/
10
11
12 /**************************************************************************/
13 /**************************************************************************/
14 /** */
15 /** USBX Component */
16 /** */
17 /** Utility */
18 /** */
19 /**************************************************************************/
20 /**************************************************************************/
21
22
23 /* Include necessary system files. */
24
25 #define UX_SOURCE_CODE
26
27 #include "ux_api.h"
28
29
30 /**************************************************************************/
31 /* */
32 /* FUNCTION RELEASE */
33 /* */
34 /* _ux_utility_pci_class_scan PORTABLE C */
35 /* 6.1 */
36 /* AUTHOR */
37 /* */
38 /* Chaoqiong Xiao, Microsoft Corporation */
39 /* */
40 /* DESCRIPTION */
41 /* */
42 /* This function scans the PCI bus from a certain position for a */
43 /* specific PCI class. */
44 /* */
45 /* INPUT */
46 /* */
47 /* pci_class PCI class requested */
48 /* bus_number PCI bus number */
49 /* device_number Device number */
50 /* function_number Function number */
51 /* current_bus_number Current bus number */
52 /* current_device_number Current device number */
53 /* current_function_number Current function number */
54 /* */
55 /* OUTPUT */
56 /* */
57 /* 32-bit value */
58 /* */
59 /* CALLS */
60 /* */
61 /* _ux_utility_pci_read PCI read utility */
62 /* */
63 /* CALLED BY */
64 /* */
65 /* USBX Components */
66 /* */
67 /* RELEASE HISTORY */
68 /* */
69 /* DATE NAME DESCRIPTION */
70 /* */
71 /* 05-19-2020 Chaoqiong Xiao Initial Version 6.0 */
72 /* 09-30-2020 Chaoqiong Xiao Modified comment(s), */
73 /* resulting in version 6.1 */
74 /* */
75 /**************************************************************************/
_ux_utility_pci_class_scan(ULONG pci_class,ULONG bus_number,ULONG device_number,ULONG function_number,ULONG * current_bus_number,ULONG * current_device_number,ULONG * current_function_number)76 ULONG _ux_utility_pci_class_scan(ULONG pci_class, ULONG bus_number, ULONG device_number,
77 ULONG function_number, ULONG *current_bus_number,
78 ULONG *current_device_number, ULONG *current_function_number)
79 {
80
81 ULONG bus_number_index;
82 ULONG device_number_index;
83 ULONG function_number_index;
84 ULONG value;
85 ULONG current_pci_class;
86
87
88 /* Scan all bus. */
89 for (bus_number_index = bus_number; bus_number_index <= UX_PCI_NB_BUS; bus_number_index++)
90 {
91
92 /* Scan all devices. */
93 for(device_number_index = device_number;device_number_index <= UX_PCI_NB_DEVICE; device_number_index++)
94 {
95
96 /* Scan all functions. */
97 for(function_number_index = function_number; function_number_index <= UX_PCI_NB_FUNCTIONS; function_number_index++)
98 {
99
100 /* Reset all PCI address for next loop. */
101 function_number = 0;
102 device_number = 0;
103 bus_number = 0;
104
105 /* Read the PCI class bus/device/function. */
106 value = _ux_utility_pci_read(bus_number_index, device_number_index, function_number_index,
107 UX_PCI_CFG_REVISION,32);
108
109 /* Isolate the class code which is in the upper 3 bytes. */
110 current_pci_class = (value >> 8) & 0x00ffffff;
111
112 /* Do we have a match with the demanded class? */
113 if(current_pci_class == pci_class)
114 {
115
116 /* Return the position of this device on the PCI */
117 *current_bus_number = bus_number_index;
118 *current_device_number = device_number_index;
119 *current_function_number = function_number_index;
120
121 /* Return success! */
122 return(UX_SUCCESS);
123 }
124 }
125 }
126 }
127
128 /* Return an error since we didn't find anything. */
129 return(UX_ERROR);
130 }
131
132
