Commit | Line | Data |
---|---|---|
b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
26893c13 DH |
2 | /* |
3 | * leon_pci.c: LEON Host PCI support | |
4 | * | |
5 | * Copyright (C) 2011 Aeroflex Gaisler AB, Daniel Hellstrom | |
6 | * | |
7 | * Code is partially derived from pcic.c | |
8 | */ | |
9 | ||
10 | #include <linux/of_device.h> | |
11 | #include <linux/kernel.h> | |
12 | #include <linux/pci.h> | |
7b64db60 | 13 | #include <linux/export.h> |
26893c13 DH |
14 | #include <asm/leon.h> |
15 | #include <asm/leon_pci.h> | |
16 | ||
17 | /* The LEON architecture does not rely on a BIOS or bootloader to setup | |
18 | * PCI for us. The Linux generic routines are used to setup resources, | |
ac1edcc5 BH |
19 | * reset values of configuration-space register settings are preserved. |
20 | * | |
21 | * PCI Memory and Prefetchable Memory is direct-mapped. However I/O Space is | |
22 | * accessed through a Window which is translated to low 64KB in PCI space, the | |
23 | * first 4KB is not used so 60KB is available. | |
26893c13 DH |
24 | */ |
25 | void leon_pci_init(struct platform_device *ofdev, struct leon_pci_info *info) | |
26 | { | |
2b591616 | 27 | LIST_HEAD(resources); |
26893c13 | 28 | struct pci_bus *root_bus; |
b483e3c1 LP |
29 | struct pci_host_bridge *bridge; |
30 | int ret; | |
31 | ||
32 | bridge = pci_alloc_host_bridge(0); | |
33 | if (!bridge) | |
34 | return; | |
26893c13 | 35 | |
ac1edcc5 BH |
36 | pci_add_resource_offset(&resources, &info->io_space, |
37 | info->io_space.start - 0x1000); | |
2b591616 | 38 | pci_add_resource(&resources, &info->mem_space); |
aa90b694 DH |
39 | info->busn.flags = IORESOURCE_BUS; |
40 | pci_add_resource(&resources, &info->busn); | |
26893c13 | 41 | |
b483e3c1 LP |
42 | list_splice_init(&resources, &bridge->windows); |
43 | bridge->dev.parent = &ofdev->dev; | |
44 | bridge->sysdata = info; | |
45 | bridge->busnr = 0; | |
46 | bridge->ops = info->ops; | |
47 | bridge->swizzle_irq = pci_common_swizzle; | |
48 | bridge->map_irq = info->map_irq; | |
49 | ||
50 | ret = pci_scan_root_bus_bridge(bridge); | |
51 | if (ret) { | |
52 | pci_free_host_bridge(bridge); | |
9e808eb6 | 53 | return; |
26893c13 | 54 | } |
9e808eb6 | 55 | |
b483e3c1 | 56 | root_bus = bridge->bus; |
9e808eb6 BH |
57 | |
58 | /* Assign devices with resources */ | |
59 | pci_assign_unassigned_resources(); | |
60 | pci_bus_add_devices(root_bus); | |
26893c13 DH |
61 | } |
62 | ||
7c9503b8 | 63 | void pcibios_fixup_bus(struct pci_bus *pbus) |
26893c13 | 64 | { |
26893c13 DH |
65 | struct pci_dev *dev; |
66 | int i, has_io, has_mem; | |
67 | u16 cmd; | |
68 | ||
26893c13 DH |
69 | list_for_each_entry(dev, &pbus->devices, bus_list) { |
70 | /* | |
71 | * We can not rely on that the bootloader has enabled I/O | |
72 | * or memory access to PCI devices. Instead we enable it here | |
73 | * if the device has BARs of respective type. | |
74 | */ | |
75 | has_io = has_mem = 0; | |
76 | for (i = 0; i < PCI_ROM_RESOURCE; i++) { | |
77 | unsigned long f = dev->resource[i].flags; | |
78 | if (f & IORESOURCE_IO) | |
79 | has_io = 1; | |
80 | else if (f & IORESOURCE_MEM) | |
81 | has_mem = 1; | |
82 | } | |
83 | /* ROM BARs are mapped into 32-bit memory space */ | |
84 | if (dev->resource[PCI_ROM_RESOURCE].end != 0) { | |
85 | dev->resource[PCI_ROM_RESOURCE].flags |= | |
86 | IORESOURCE_ROM_ENABLE; | |
87 | has_mem = 1; | |
88 | } | |
89 | pci_bus_read_config_word(pbus, dev->devfn, PCI_COMMAND, &cmd); | |
90 | if (has_io && !(cmd & PCI_COMMAND_IO)) { | |
91 | #ifdef CONFIG_PCI_DEBUG | |
92 | printk(KERN_INFO "LEONPCI: Enabling I/O for dev %s\n", | |
93 | pci_name(dev)); | |
94 | #endif | |
95 | cmd |= PCI_COMMAND_IO; | |
96 | pci_bus_write_config_word(pbus, dev->devfn, PCI_COMMAND, | |
97 | cmd); | |
98 | } | |
99 | if (has_mem && !(cmd & PCI_COMMAND_MEMORY)) { | |
100 | #ifdef CONFIG_PCI_DEBUG | |
101 | printk(KERN_INFO "LEONPCI: Enabling MEMORY for dev" | |
102 | "%s\n", pci_name(dev)); | |
103 | #endif | |
104 | cmd |= PCI_COMMAND_MEMORY; | |
105 | pci_bus_write_config_word(pbus, dev->devfn, PCI_COMMAND, | |
106 | cmd); | |
107 | } | |
108 | } | |
109 | } |