xref: /linux/arch/loongarch/pci/pci.c (revision 3c4fc7bf4c9e66fe71abcbf93f62f4ddb89b7f15)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
4  */
5 #include <linux/kernel.h>
6 #include <linux/export.h>
7 #include <linux/init.h>
8 #include <linux/acpi.h>
9 #include <linux/types.h>
10 #include <linux/pci.h>
11 #include <linux/vgaarb.h>
12 #include <asm/loongson.h>
13 
14 #define PCI_DEVICE_ID_LOONGSON_HOST     0x7a00
15 #define PCI_DEVICE_ID_LOONGSON_DC1      0x7a06
16 #define PCI_DEVICE_ID_LOONGSON_DC2      0x7a36
17 
18 int raw_pci_read(unsigned int domain, unsigned int bus, unsigned int devfn,
19 						int reg, int len, u32 *val)
20 {
21 	struct pci_bus *bus_tmp = pci_find_bus(domain, bus);
22 
23 	if (bus_tmp)
24 		return bus_tmp->ops->read(bus_tmp, devfn, reg, len, val);
25 	return -EINVAL;
26 }
27 
28 int raw_pci_write(unsigned int domain, unsigned int bus, unsigned int devfn,
29 						int reg, int len, u32 val)
30 {
31 	struct pci_bus *bus_tmp = pci_find_bus(domain, bus);
32 
33 	if (bus_tmp)
34 		return bus_tmp->ops->write(bus_tmp, devfn, reg, len, val);
35 	return -EINVAL;
36 }
37 
38 phys_addr_t mcfg_addr_init(int node)
39 {
40 	return (((u64)node << 44) | MCFG_EXT_PCICFG_BASE);
41 }
42 
43 static int __init pcibios_init(void)
44 {
45 	unsigned int lsize;
46 
47 	/*
48 	 * Set PCI cacheline size to that of the highest level in the
49 	 * cache hierarchy.
50 	 */
51 	lsize = cpu_dcache_line_size();
52 	lsize = cpu_vcache_line_size() ? : lsize;
53 	lsize = cpu_scache_line_size() ? : lsize;
54 
55 	BUG_ON(!lsize);
56 
57 	pci_dfl_cache_line_size = lsize >> 2;
58 
59 	pr_debug("PCI: pci_cache_line_size set to %d bytes\n", lsize);
60 
61 	return 0;
62 }
63 
64 subsys_initcall(pcibios_init);
65 
66 int pcibios_device_add(struct pci_dev *dev)
67 {
68 	int id;
69 	struct irq_domain *dom;
70 
71 	id = pci_domain_nr(dev->bus);
72 	dom = irq_find_matching_fwnode(get_pch_msi_handle(id), DOMAIN_BUS_PCI_MSI);
73 	dev_set_msi_domain(&dev->dev, dom);
74 
75 	return 0;
76 }
77 
78 int pcibios_alloc_irq(struct pci_dev *dev)
79 {
80 	if (acpi_disabled)
81 		return 0;
82 	if (pci_dev_msi_enabled(dev))
83 		return 0;
84 	return acpi_pci_irq_enable(dev);
85 }
86 
87 static void pci_fixup_vgadev(struct pci_dev *pdev)
88 {
89 	struct pci_dev *devp = NULL;
90 
91 	while ((devp = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, devp))) {
92 		if (devp->vendor != PCI_VENDOR_ID_LOONGSON) {
93 			vga_set_default_device(devp);
94 			dev_info(&pdev->dev,
95 				"Overriding boot device as %X:%X\n",
96 				devp->vendor, devp->device);
97 		}
98 	}
99 }
100 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LOONGSON, PCI_DEVICE_ID_LOONGSON_DC1, pci_fixup_vgadev);
101 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LOONGSON, PCI_DEVICE_ID_LOONGSON_DC2, pci_fixup_vgadev);
102