1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright (C) NEC Electronics Corporation 2004-2006
4 *
5 * This file is based on the arch/mips/pci/ops-vr41xx.c
6 *
7 * Copyright 2001 MontaVista Software Inc.
8 */
9
10 #include <linux/pci.h>
11 #include <linux/kernel.h>
12 #include <linux/types.h>
13
14 #include <asm/addrspace.h>
15
16 #include <asm/emma/emma2rh.h>
17
18 #define RTABORT (0x1<<9)
19 #define RMABORT (0x1<<10)
20 #define EMMA2RH_PCI_SLOT_NUM 9 /* 0000:09.0 is final PCI device */
21
22 /*
23 * access config space
24 */
25
check_args(struct pci_bus * bus,u32 devfn,u32 * bus_num)26 static int check_args(struct pci_bus *bus, u32 devfn, u32 * bus_num)
27 {
28 /* check if the bus is top-level */
29 if (bus->parent != NULL)
30 *bus_num = bus->number;
31 else
32 *bus_num = 0;
33
34 if (*bus_num == 0) {
35 /* Type 0 */
36 if (PCI_SLOT(devfn) >= 10)
37 return PCIBIOS_DEVICE_NOT_FOUND;
38 } else {
39 /* Type 1 */
40 if ((*bus_num >= 64) || (PCI_SLOT(devfn) >= 16))
41 return PCIBIOS_DEVICE_NOT_FOUND;
42 }
43 return 0;
44 }
45
set_pci_configuration_address(unsigned char bus_num,unsigned int devfn,int where)46 static inline int set_pci_configuration_address(unsigned char bus_num,
47 unsigned int devfn, int where)
48 {
49 u32 config_win0;
50
51 emma2rh_out32(EMMA2RH_PCI_INT, ~RMABORT);
52 if (bus_num == 0)
53 /*
54 * Type 0 configuration
55 */
56 config_win0 = (1 << (22 + PCI_SLOT(devfn))) | (5 << 9);
57 else
58 /*
59 * Type 1 configuration
60 */
61 config_win0 = (bus_num << 26) | (PCI_SLOT(devfn) << 22) |
62 (1 << 15) | (5 << 9);
63
64 emma2rh_out32(EMMA2RH_PCI_IWIN0_CTR, config_win0);
65
66 return 0;
67 }
68
pci_config_read(struct pci_bus * bus,unsigned int devfn,int where,int size,uint32_t * val)69 static int pci_config_read(struct pci_bus *bus, unsigned int devfn, int where,
70 int size, uint32_t * val)
71 {
72 u32 bus_num;
73 u32 base = KSEG1ADDR(EMMA2RH_PCI_CONFIG_BASE);
74 u32 backup_win0;
75 u32 data;
76
77 *val = 0xffffffffU;
78
79 if (check_args(bus, devfn, &bus_num) == PCIBIOS_DEVICE_NOT_FOUND)
80 return PCIBIOS_DEVICE_NOT_FOUND;
81
82 backup_win0 = emma2rh_in32(EMMA2RH_PCI_IWIN0_CTR);
83
84 if (set_pci_configuration_address(bus_num, devfn, where) < 0)
85 return PCIBIOS_DEVICE_NOT_FOUND;
86
87 data =
88 *(volatile u32 *)(base + (PCI_FUNC(devfn) << 8) +
89 (where & 0xfffffffc));
90
91 switch (size) {
92 case 1:
93 *val = (data >> ((where & 3) << 3)) & 0xffU;
94 break;
95 case 2:
96 *val = (data >> ((where & 2) << 3)) & 0xffffU;
97 break;
98 case 4:
99 *val = data;
100 break;
101 default:
102 emma2rh_out32(EMMA2RH_PCI_IWIN0_CTR, backup_win0);
103 return PCIBIOS_FUNC_NOT_SUPPORTED;
104 }
105
106 emma2rh_out32(EMMA2RH_PCI_IWIN0_CTR, backup_win0);
107
108 if (emma2rh_in32(EMMA2RH_PCI_INT) & RMABORT)
109 return PCIBIOS_DEVICE_NOT_FOUND;
110
111 return PCIBIOS_SUCCESSFUL;
112 }
113
pci_config_write(struct pci_bus * bus,unsigned int devfn,int where,int size,u32 val)114 static int pci_config_write(struct pci_bus *bus, unsigned int devfn, int where,
115 int size, u32 val)
116 {
117 u32 bus_num;
118 u32 base = KSEG1ADDR(EMMA2RH_PCI_CONFIG_BASE);
119 u32 backup_win0;
120 u32 data;
121 int shift;
122
123 if (check_args(bus, devfn, &bus_num) == PCIBIOS_DEVICE_NOT_FOUND)
124 return PCIBIOS_DEVICE_NOT_FOUND;
125
126 backup_win0 = emma2rh_in32(EMMA2RH_PCI_IWIN0_CTR);
127
128 if (set_pci_configuration_address(bus_num, devfn, where) < 0)
129 return PCIBIOS_DEVICE_NOT_FOUND;
130
131 /* read modify write */
132 data =
133 *(volatile u32 *)(base + (PCI_FUNC(devfn) << 8) +
134 (where & 0xfffffffc));
135
136 switch (size) {
137 case 1:
138 shift = (where & 3) << 3;
139 data &= ~(0xffU << shift);
140 data |= ((val & 0xffU) << shift);
141 break;
142 case 2:
143 shift = (where & 2) << 3;
144 data &= ~(0xffffU << shift);
145 data |= ((val & 0xffffU) << shift);
146 break;
147 case 4:
148 data = val;
149 break;
150 default:
151 emma2rh_out32(EMMA2RH_PCI_IWIN0_CTR, backup_win0);
152 return PCIBIOS_FUNC_NOT_SUPPORTED;
153 }
154 *(volatile u32 *)(base + (PCI_FUNC(devfn) << 8) +
155 (where & 0xfffffffc)) = data;
156
157 emma2rh_out32(EMMA2RH_PCI_IWIN0_CTR, backup_win0);
158 if (emma2rh_in32(EMMA2RH_PCI_INT) & RMABORT)
159 return PCIBIOS_DEVICE_NOT_FOUND;
160
161 return PCIBIOS_SUCCESSFUL;
162 }
163
164 struct pci_ops emma2rh_pci_ops = {
165 .read = pci_config_read,
166 .write = pci_config_write,
167 };
168