xref: /openbmc/linux/arch/loongarch/pci/pci.c (revision b868a02e)
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/cacheflush.h>
13 #include <asm/loongson.h>
14 
15 #define PCI_DEVICE_ID_LOONGSON_HOST     0x7a00
16 #define PCI_DEVICE_ID_LOONGSON_DC1      0x7a06
17 #define PCI_DEVICE_ID_LOONGSON_DC2      0x7a36
18 
19 int raw_pci_read(unsigned int domain, unsigned int bus, unsigned int devfn,
20 						int reg, int len, u32 *val)
21 {
22 	struct pci_bus *bus_tmp = pci_find_bus(domain, bus);
23 
24 	if (bus_tmp)
25 		return bus_tmp->ops->read(bus_tmp, devfn, reg, len, val);
26 	return -EINVAL;
27 }
28 
29 int raw_pci_write(unsigned int domain, unsigned int bus, unsigned int devfn,
30 						int reg, int len, u32 val)
31 {
32 	struct pci_bus *bus_tmp = pci_find_bus(domain, bus);
33 
34 	if (bus_tmp)
35 		return bus_tmp->ops->write(bus_tmp, devfn, reg, len, val);
36 	return -EINVAL;
37 }
38 
39 phys_addr_t mcfg_addr_init(int node)
40 {
41 	return (((u64)node << 44) | MCFG_EXT_PCICFG_BASE);
42 }
43 
44 static int __init pcibios_init(void)
45 {
46 	unsigned int lsize;
47 
48 	/*
49 	 * Set PCI cacheline size to that of the last level in the
50 	 * cache hierarchy.
51 	 */
52 	lsize = cpu_last_level_cache_line_size();
53 
54 	BUG_ON(!lsize);
55 
56 	pci_dfl_cache_line_size = lsize >> 2;
57 
58 	pr_debug("PCI: pci_cache_line_size set to %d bytes\n", lsize);
59 
60 	return 0;
61 }
62 
63 subsys_initcall(pcibios_init);
64 
65 int pcibios_device_add(struct pci_dev *dev)
66 {
67 	int id;
68 	struct irq_domain *dom;
69 
70 	id = pci_domain_nr(dev->bus);
71 	dom = irq_find_matching_fwnode(get_pch_msi_handle(id), DOMAIN_BUS_PCI_MSI);
72 	dev_set_msi_domain(&dev->dev, dom);
73 
74 	return 0;
75 }
76 
77 int pcibios_alloc_irq(struct pci_dev *dev)
78 {
79 	if (acpi_disabled)
80 		return 0;
81 	if (pci_dev_msi_enabled(dev))
82 		return 0;
83 	return acpi_pci_irq_enable(dev);
84 }
85 
86 static void pci_fixup_vgadev(struct pci_dev *pdev)
87 {
88 	struct pci_dev *devp = NULL;
89 
90 	while ((devp = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, devp))) {
91 		if (devp->vendor != PCI_VENDOR_ID_LOONGSON) {
92 			vga_set_default_device(devp);
93 			dev_info(&pdev->dev,
94 				"Overriding boot device as %X:%X\n",
95 				devp->vendor, devp->device);
96 		}
97 	}
98 }
99 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LOONGSON, PCI_DEVICE_ID_LOONGSON_DC1, pci_fixup_vgadev);
100 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LOONGSON, PCI_DEVICE_ID_LOONGSON_DC2, pci_fixup_vgadev);
101