xref: /openbmc/linux/arch/sparc/kernel/leon_pci.c (revision b6bec26c)
1 /*
2  * leon_pci.c: LEON Host PCI support
3  *
4  * Copyright (C) 2011 Aeroflex Gaisler AB, Daniel Hellstrom
5  *
6  * Code is partially derived from pcic.c
7  */
8 
9 #include <linux/of_device.h>
10 #include <linux/kernel.h>
11 #include <linux/pci.h>
12 #include <linux/export.h>
13 #include <asm/leon.h>
14 #include <asm/leon_pci.h>
15 
16 /* The LEON architecture does not rely on a BIOS or bootloader to setup
17  * PCI for us. The Linux generic routines are used to setup resources,
18  * reset values of configuration-space register settings are preserved.
19  *
20  * PCI Memory and Prefetchable Memory is direct-mapped. However I/O Space is
21  * accessed through a Window which is translated to low 64KB in PCI space, the
22  * first 4KB is not used so 60KB is available.
23  */
24 void leon_pci_init(struct platform_device *ofdev, struct leon_pci_info *info)
25 {
26 	LIST_HEAD(resources);
27 	struct pci_bus *root_bus;
28 
29 	pci_add_resource_offset(&resources, &info->io_space,
30 				info->io_space.start - 0x1000);
31 	pci_add_resource(&resources, &info->mem_space);
32 
33 	root_bus = pci_scan_root_bus(&ofdev->dev, 0, info->ops, info,
34 				     &resources);
35 	if (root_bus) {
36 		/* Setup IRQs of all devices using custom routines */
37 		pci_fixup_irqs(pci_common_swizzle, info->map_irq);
38 
39 		/* Assign devices with resources */
40 		pci_assign_unassigned_resources();
41 	} else {
42 		pci_free_resource_list(&resources);
43 	}
44 }
45 
46 void pcibios_fixup_bus(struct pci_bus *pbus)
47 {
48 	struct pci_dev *dev;
49 	int i, has_io, has_mem;
50 	u16 cmd;
51 
52 	list_for_each_entry(dev, &pbus->devices, bus_list) {
53 		/*
54 		 * We can not rely on that the bootloader has enabled I/O
55 		 * or memory access to PCI devices. Instead we enable it here
56 		 * if the device has BARs of respective type.
57 		 */
58 		has_io = has_mem = 0;
59 		for (i = 0; i < PCI_ROM_RESOURCE; i++) {
60 			unsigned long f = dev->resource[i].flags;
61 			if (f & IORESOURCE_IO)
62 				has_io = 1;
63 			else if (f & IORESOURCE_MEM)
64 				has_mem = 1;
65 		}
66 		/* ROM BARs are mapped into 32-bit memory space */
67 		if (dev->resource[PCI_ROM_RESOURCE].end != 0) {
68 			dev->resource[PCI_ROM_RESOURCE].flags |=
69 							IORESOURCE_ROM_ENABLE;
70 			has_mem = 1;
71 		}
72 		pci_bus_read_config_word(pbus, dev->devfn, PCI_COMMAND, &cmd);
73 		if (has_io && !(cmd & PCI_COMMAND_IO)) {
74 #ifdef CONFIG_PCI_DEBUG
75 			printk(KERN_INFO "LEONPCI: Enabling I/O for dev %s\n",
76 					 pci_name(dev));
77 #endif
78 			cmd |= PCI_COMMAND_IO;
79 			pci_bus_write_config_word(pbus, dev->devfn, PCI_COMMAND,
80 									cmd);
81 		}
82 		if (has_mem && !(cmd & PCI_COMMAND_MEMORY)) {
83 #ifdef CONFIG_PCI_DEBUG
84 			printk(KERN_INFO "LEONPCI: Enabling MEMORY for dev"
85 					 "%s\n", pci_name(dev));
86 #endif
87 			cmd |= PCI_COMMAND_MEMORY;
88 			pci_bus_write_config_word(pbus, dev->devfn, PCI_COMMAND,
89 									cmd);
90 		}
91 	}
92 }
93 
94 resource_size_t pcibios_align_resource(void *data, const struct resource *res,
95 				resource_size_t size, resource_size_t align)
96 {
97 	return res->start;
98 }
99 
100 int pcibios_enable_device(struct pci_dev *dev, int mask)
101 {
102 	return pci_enable_resources(dev, mask);
103 }
104 
105 /* in/out routines taken from pcic.c
106  *
107  * This probably belongs here rather than ioport.c because
108  * we do not want this crud linked into SBus kernels.
109  * Also, think for a moment about likes of floppy.c that
110  * include architecture specific parts. They may want to redefine ins/outs.
111  *
112  * We do not use horrible macros here because we want to
113  * advance pointer by sizeof(size).
114  */
115 void outsb(unsigned long addr, const void *src, unsigned long count)
116 {
117 	while (count) {
118 		count -= 1;
119 		outb(*(const char *)src, addr);
120 		src += 1;
121 		/* addr += 1; */
122 	}
123 }
124 EXPORT_SYMBOL(outsb);
125 
126 void outsw(unsigned long addr, const void *src, unsigned long count)
127 {
128 	while (count) {
129 		count -= 2;
130 		outw(*(const short *)src, addr);
131 		src += 2;
132 		/* addr += 2; */
133 	}
134 }
135 EXPORT_SYMBOL(outsw);
136 
137 void outsl(unsigned long addr, const void *src, unsigned long count)
138 {
139 	while (count) {
140 		count -= 4;
141 		outl(*(const long *)src, addr);
142 		src += 4;
143 		/* addr += 4; */
144 	}
145 }
146 EXPORT_SYMBOL(outsl);
147 
148 void insb(unsigned long addr, void *dst, unsigned long count)
149 {
150 	while (count) {
151 		count -= 1;
152 		*(unsigned char *)dst = inb(addr);
153 		dst += 1;
154 		/* addr += 1; */
155 	}
156 }
157 EXPORT_SYMBOL(insb);
158 
159 void insw(unsigned long addr, void *dst, unsigned long count)
160 {
161 	while (count) {
162 		count -= 2;
163 		*(unsigned short *)dst = inw(addr);
164 		dst += 2;
165 		/* addr += 2; */
166 	}
167 }
168 EXPORT_SYMBOL(insw);
169 
170 void insl(unsigned long addr, void *dst, unsigned long count)
171 {
172 	while (count) {
173 		count -= 4;
174 		/*
175 		 * XXX I am sure we are in for an unaligned trap here.
176 		 */
177 		*(unsigned long *)dst = inl(addr);
178 		dst += 4;
179 		/* addr += 4; */
180 	}
181 }
182 EXPORT_SYMBOL(insl);
183