xref: /linux/arch/sparc/kernel/leon_pci.c (revision b43ab901d671e3e3cad425ea5e9a3c74e266dcdd)
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 confuration-space registers settings ae preseved.
19  */
20 void leon_pci_init(struct platform_device *ofdev, struct leon_pci_info *info)
21 {
22 	LIST_HEAD(resources);
23 	struct pci_bus *root_bus;
24 
25 	pci_add_resource(&resources, &info->io_space);
26 	pci_add_resource(&resources, &info->mem_space);
27 
28 	root_bus = pci_scan_root_bus(&ofdev->dev, 0, info->ops, info,
29 				     &resources);
30 	if (root_bus) {
31 		/* Setup IRQs of all devices using custom routines */
32 		pci_fixup_irqs(pci_common_swizzle, info->map_irq);
33 
34 		/* Assign devices with resources */
35 		pci_assign_unassigned_resources();
36 	} else {
37 		pci_free_resource_list(&resources);
38 	}
39 }
40 
41 /* PCI Memory and Prefetchable Memory is direct-mapped. However I/O Space is
42  * accessed through a Window which is translated to low 64KB in PCI space, the
43  * first 4KB is not used so 60KB is available.
44  *
45  * This function is used by generic code to translate resource addresses into
46  * PCI addresses.
47  */
48 void pcibios_resource_to_bus(struct pci_dev *dev, struct pci_bus_region *region,
49 			     struct resource *res)
50 {
51 	struct leon_pci_info *info = dev->bus->sysdata;
52 
53 	region->start = res->start;
54 	region->end = res->end;
55 
56 	if (res->flags & IORESOURCE_IO) {
57 		region->start -= (info->io_space.start - 0x1000);
58 		region->end -= (info->io_space.start - 0x1000);
59 	}
60 }
61 EXPORT_SYMBOL(pcibios_resource_to_bus);
62 
63 /* see pcibios_resource_to_bus() comment */
64 void pcibios_bus_to_resource(struct pci_dev *dev, struct resource *res,
65 			     struct pci_bus_region *region)
66 {
67 	struct leon_pci_info *info = dev->bus->sysdata;
68 
69 	res->start = region->start;
70 	res->end = region->end;
71 
72 	if (res->flags & IORESOURCE_IO) {
73 		res->start += (info->io_space.start - 0x1000);
74 		res->end += (info->io_space.start - 0x1000);
75 	}
76 }
77 EXPORT_SYMBOL(pcibios_bus_to_resource);
78 
79 void __devinit pcibios_fixup_bus(struct pci_bus *pbus)
80 {
81 	struct leon_pci_info *info = pbus->sysdata;
82 	struct pci_dev *dev;
83 	int i, has_io, has_mem;
84 	u16 cmd;
85 
86 	list_for_each_entry(dev, &pbus->devices, bus_list) {
87 		/*
88 		 * We can not rely on that the bootloader has enabled I/O
89 		 * or memory access to PCI devices. Instead we enable it here
90 		 * if the device has BARs of respective type.
91 		 */
92 		has_io = has_mem = 0;
93 		for (i = 0; i < PCI_ROM_RESOURCE; i++) {
94 			unsigned long f = dev->resource[i].flags;
95 			if (f & IORESOURCE_IO)
96 				has_io = 1;
97 			else if (f & IORESOURCE_MEM)
98 				has_mem = 1;
99 		}
100 		/* ROM BARs are mapped into 32-bit memory space */
101 		if (dev->resource[PCI_ROM_RESOURCE].end != 0) {
102 			dev->resource[PCI_ROM_RESOURCE].flags |=
103 							IORESOURCE_ROM_ENABLE;
104 			has_mem = 1;
105 		}
106 		pci_bus_read_config_word(pbus, dev->devfn, PCI_COMMAND, &cmd);
107 		if (has_io && !(cmd & PCI_COMMAND_IO)) {
108 #ifdef CONFIG_PCI_DEBUG
109 			printk(KERN_INFO "LEONPCI: Enabling I/O for dev %s\n",
110 					 pci_name(dev));
111 #endif
112 			cmd |= PCI_COMMAND_IO;
113 			pci_bus_write_config_word(pbus, dev->devfn, PCI_COMMAND,
114 									cmd);
115 		}
116 		if (has_mem && !(cmd & PCI_COMMAND_MEMORY)) {
117 #ifdef CONFIG_PCI_DEBUG
118 			printk(KERN_INFO "LEONPCI: Enabling MEMORY for dev"
119 					 "%s\n", pci_name(dev));
120 #endif
121 			cmd |= PCI_COMMAND_MEMORY;
122 			pci_bus_write_config_word(pbus, dev->devfn, PCI_COMMAND,
123 									cmd);
124 		}
125 	}
126 }
127 
128 /*
129  * Other archs parse arguments here.
130  */
131 char * __devinit pcibios_setup(char *str)
132 {
133 	return str;
134 }
135 
136 resource_size_t pcibios_align_resource(void *data, const struct resource *res,
137 				resource_size_t size, resource_size_t align)
138 {
139 	return res->start;
140 }
141 
142 int pcibios_enable_device(struct pci_dev *dev, int mask)
143 {
144 	return pci_enable_resources(dev, mask);
145 }
146 
147 struct device_node *pci_device_to_OF_node(struct pci_dev *pdev)
148 {
149 	/*
150 	 * Currently the OpenBoot nodes are not connected with the PCI device,
151 	 * this is because the LEON PROM does not create PCI nodes. Eventually
152 	 * this will change and the same approach as pcic.c can be used to
153 	 * match PROM nodes with pci devices.
154 	 */
155 	return NULL;
156 }
157 EXPORT_SYMBOL(pci_device_to_OF_node);
158 
159 void __devinit pcibios_update_irq(struct pci_dev *dev, int irq)
160 {
161 #ifdef CONFIG_PCI_DEBUG
162 	printk(KERN_DEBUG "LEONPCI: Assigning IRQ %02d to %s\n", irq,
163 		pci_name(dev));
164 #endif
165 	pci_write_config_byte(dev, PCI_INTERRUPT_LINE, irq);
166 }
167 
168 /* in/out routines taken from pcic.c
169  *
170  * This probably belongs here rather than ioport.c because
171  * we do not want this crud linked into SBus kernels.
172  * Also, think for a moment about likes of floppy.c that
173  * include architecture specific parts. They may want to redefine ins/outs.
174  *
175  * We do not use horrible macros here because we want to
176  * advance pointer by sizeof(size).
177  */
178 void outsb(unsigned long addr, const void *src, unsigned long count)
179 {
180 	while (count) {
181 		count -= 1;
182 		outb(*(const char *)src, addr);
183 		src += 1;
184 		/* addr += 1; */
185 	}
186 }
187 EXPORT_SYMBOL(outsb);
188 
189 void outsw(unsigned long addr, const void *src, unsigned long count)
190 {
191 	while (count) {
192 		count -= 2;
193 		outw(*(const short *)src, addr);
194 		src += 2;
195 		/* addr += 2; */
196 	}
197 }
198 EXPORT_SYMBOL(outsw);
199 
200 void outsl(unsigned long addr, const void *src, unsigned long count)
201 {
202 	while (count) {
203 		count -= 4;
204 		outl(*(const long *)src, addr);
205 		src += 4;
206 		/* addr += 4; */
207 	}
208 }
209 EXPORT_SYMBOL(outsl);
210 
211 void insb(unsigned long addr, void *dst, unsigned long count)
212 {
213 	while (count) {
214 		count -= 1;
215 		*(unsigned char *)dst = inb(addr);
216 		dst += 1;
217 		/* addr += 1; */
218 	}
219 }
220 EXPORT_SYMBOL(insb);
221 
222 void insw(unsigned long addr, void *dst, unsigned long count)
223 {
224 	while (count) {
225 		count -= 2;
226 		*(unsigned short *)dst = inw(addr);
227 		dst += 2;
228 		/* addr += 2; */
229 	}
230 }
231 EXPORT_SYMBOL(insw);
232 
233 void insl(unsigned long addr, void *dst, unsigned long count)
234 {
235 	while (count) {
236 		count -= 4;
237 		/*
238 		 * XXX I am sure we are in for an unaligned trap here.
239 		 */
240 		*(unsigned long *)dst = inl(addr);
241 		dst += 4;
242 		/* addr += 4; */
243 	}
244 }
245 EXPORT_SYMBOL(insl);
246