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
 26static 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
 46static 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
 69static 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
114static 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
164struct pci_ops emma2rh_pci_ops = {
165	.read = pci_config_read,
166	.write = pci_config_write,
167};