xref: /openbmc/linux/arch/mips/loongson2ef/common/pci.c (revision 85250a24)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) 2007 Lemote, Inc. & Institute of Computing Technology
4  * Author: Fuxin Zhang, zhangfx@lemote.com
5  */
6 #include <linux/pci.h>
7 
8 #include <pci.h>
9 #include <loongson.h>
10 
11 static struct resource loongson_pci_mem_resource = {
12 	.name	= "pci memory space",
13 	.start	= LOONGSON_PCI_MEM_START,
14 	.end	= LOONGSON_PCI_MEM_END,
15 	.flags	= IORESOURCE_MEM,
16 };
17 
18 static struct resource loongson_pci_io_resource = {
19 	.name	= "pci io space",
20 	.start	= LOONGSON_PCI_IO_START,
21 	.end	= IO_SPACE_LIMIT,
22 	.flags	= IORESOURCE_IO,
23 };
24 
25 static struct pci_controller  loongson_pci_controller = {
26 	.pci_ops	= &loongson_pci_ops,
27 	.io_resource	= &loongson_pci_io_resource,
28 	.mem_resource	= &loongson_pci_mem_resource,
29 	.mem_offset	= 0x00000000UL,
30 	.io_offset	= 0x00000000UL,
31 };
32 
33 static void __init setup_pcimap(void)
34 {
35 	/*
36 	 * local to PCI mapping for CPU accessing PCI space
37 	 * CPU address space [256M,448M] is window for accessing pci space
38 	 * we set pcimap_lo[0,1,2] to map it to pci space[0M,64M], [320M,448M]
39 	 *
40 	 * pcimap: PCI_MAP2  PCI_Mem_Lo2 PCI_Mem_Lo1 PCI_Mem_Lo0
41 	 *	     [<2G]   [384M,448M] [320M,384M] [0M,64M]
42 	 */
43 	LOONGSON_PCIMAP = LOONGSON_PCIMAP_PCIMAP_2 |
44 		LOONGSON_PCIMAP_WIN(2, LOONGSON_PCILO2_BASE) |
45 		LOONGSON_PCIMAP_WIN(1, LOONGSON_PCILO1_BASE) |
46 		LOONGSON_PCIMAP_WIN(0, 0);
47 
48 	/*
49 	 * PCI-DMA to local mapping: [2G,2G+256M] -> [0M,256M]
50 	 */
51 	LOONGSON_PCIBASE0 = 0x80000000ul;   /* base: 2G -> mmap: 0M */
52 	/* size: 256M, burst transmission, pre-fetch enable, 64bit */
53 	LOONGSON_PCI_HIT0_SEL_L = 0xc000000cul;
54 	LOONGSON_PCI_HIT0_SEL_H = 0xfffffffful;
55 	LOONGSON_PCI_HIT1_SEL_L = 0x00000006ul; /* set this BAR as invalid */
56 	LOONGSON_PCI_HIT1_SEL_H = 0x00000000ul;
57 	LOONGSON_PCI_HIT2_SEL_L = 0x00000006ul; /* set this BAR as invalid */
58 	LOONGSON_PCI_HIT2_SEL_H = 0x00000000ul;
59 
60 	/* avoid deadlock of PCI reading/writing lock operation */
61 	LOONGSON_PCI_ISR4C = 0xd2000001ul;
62 
63 	/* can not change gnt to break pci transfer when device's gnt not
64 	deassert for some broken device */
65 	LOONGSON_PXARB_CFG = 0x00fe0105ul;
66 
67 #ifdef CONFIG_CPU_SUPPORTS_ADDRWINCFG
68 	/*
69 	 * set cpu addr window2 to map CPU address space to PCI address space
70 	 */
71 	LOONGSON_ADDRWIN_CPUTOPCI(ADDRWIN_WIN2, LOONGSON_CPU_MEM_SRC,
72 		LOONGSON_PCI_MEM_DST, MMAP_CPUTOPCI_SIZE);
73 #endif
74 }
75 
76 static int __init pcibios_init(void)
77 {
78 	setup_pcimap();
79 
80 	loongson_pci_controller.io_map_base = mips_io_port_base;
81 	register_pci_controller(&loongson_pci_controller);
82 
83 
84 	return 0;
85 }
86 
87 arch_initcall(pcibios_init);
88