1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *  ops-vr41xx.c, PCI configuration routines for the PCIU of NEC VR4100 series.
4 *
5 *  Copyright (C) 2001-2003 MontaVista Software Inc.
6 *    Author: Yoichi Yuasa <source@mvista.com>
7 *  Copyright (C) 2004-2005  Yoichi Yuasa <yuasa@linux-mips.org>
8 */
9/*
10 * Changes:
11 *  MontaVista Software Inc. <source@mvista.com>
12 *  - New creation, NEC VR4122 and VR4131 are supported.
13 */
14#include <linux/pci.h>
15#include <linux/types.h>
16
17#include <asm/io.h>
18
19#define PCICONFDREG	(void __iomem *)KSEG1ADDR(0x0f000c14)
20#define PCICONFAREG	(void __iomem *)KSEG1ADDR(0x0f000c18)
21
22static inline int set_pci_configuration_address(unsigned char number,
23						unsigned int devfn, int where)
24{
25	if (number == 0) {
26		/*
27		 * Type 0 configuration
28		 */
29		if (PCI_SLOT(devfn) < 11 || where > 0xff)
30			return -EINVAL;
31
32		writel((1U << PCI_SLOT(devfn)) | (PCI_FUNC(devfn) << 8) |
33		       (where & 0xfc), PCICONFAREG);
34	} else {
35		/*
36		 * Type 1 configuration
37		 */
38		if (where > 0xff)
39			return -EINVAL;
40
41		writel(((uint32_t)number << 16) | ((devfn & 0xff) << 8) |
42		       (where & 0xfc) | 1U, PCICONFAREG);
43	}
44
45	return 0;
46}
47
48static int pci_config_read(struct pci_bus *bus, unsigned int devfn, int where,
49			   int size, uint32_t *val)
50{
51	uint32_t data;
52
53	*val = 0xffffffffU;
54	if (set_pci_configuration_address(bus->number, devfn, where) < 0)
55		return PCIBIOS_DEVICE_NOT_FOUND;
56
57	data = readl(PCICONFDREG);
58
59	switch (size) {
60	case 1:
61		*val = (data >> ((where & 3) << 3)) & 0xffU;
62		break;
63	case 2:
64		*val = (data >> ((where & 2) << 3)) & 0xffffU;
65		break;
66	case 4:
67		*val = data;
68		break;
69	default:
70		return PCIBIOS_FUNC_NOT_SUPPORTED;
71	}
72
73	return PCIBIOS_SUCCESSFUL;
74}
75
76static int pci_config_write(struct pci_bus *bus, unsigned int devfn, int where,
77			    int size, uint32_t val)
78{
79	uint32_t data;
80	int shift;
81
82	if (set_pci_configuration_address(bus->number, devfn, where) < 0)
83		return PCIBIOS_DEVICE_NOT_FOUND;
84
85	data = readl(PCICONFDREG);
86
87	switch (size) {
88	case 1:
89		shift = (where & 3) << 3;
90		data &= ~(0xffU << shift);
91		data |= ((val & 0xffU) << shift);
92		break;
93	case 2:
94		shift = (where & 2) << 3;
95		data &= ~(0xffffU << shift);
96		data |= ((val & 0xffffU) << shift);
97		break;
98	case 4:
99		data = val;
100		break;
101	default:
102		return PCIBIOS_FUNC_NOT_SUPPORTED;
103	}
104
105	writel(data, PCICONFDREG);
106
107	return PCIBIOS_SUCCESSFUL;
108}
109
110struct pci_ops vr41xx_pci_ops = {
111	.read	= pci_config_read,
112	.write	= pci_config_write,
113};
114