xref: /linux/arch/sparc/kernel/leon_pci.c (revision f2ee442115c9b6219083c019939a9cc0c9abb2f8)
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 	struct pci_bus *root_bus;
23 
24 	root_bus = pci_scan_bus_parented(&ofdev->dev, 0, info->ops, info);
25 	if (root_bus) {
26 		root_bus->resource[0] = &info->io_space;
27 		root_bus->resource[1] = &info->mem_space;
28 		root_bus->resource[2] = NULL;
29 
30 		/* Init all PCI devices into PCI tree */
31 		pci_bus_add_devices(root_bus);
32 
33 		/* Setup IRQs of all devices using custom routines */
34 		pci_fixup_irqs(pci_common_swizzle, info->map_irq);
35 
36 		/* Assign devices with resources */
37 		pci_assign_unassigned_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 	/* Generic PCI bus probing sets these to point at
87 	 * &io{port,mem}_resouce which is wrong for us.
88 	 */
89 	if (pbus->self == NULL) {
90 		pbus->resource[0] = &info->io_space;
91 		pbus->resource[1] = &info->mem_space;
92 		pbus->resource[2] = NULL;
93 	}
94 
95 	list_for_each_entry(dev, &pbus->devices, bus_list) {
96 		/*
97 		 * We can not rely on that the bootloader has enabled I/O
98 		 * or memory access to PCI devices. Instead we enable it here
99 		 * if the device has BARs of respective type.
100 		 */
101 		has_io = has_mem = 0;
102 		for (i = 0; i < PCI_ROM_RESOURCE; i++) {
103 			unsigned long f = dev->resource[i].flags;
104 			if (f & IORESOURCE_IO)
105 				has_io = 1;
106 			else if (f & IORESOURCE_MEM)
107 				has_mem = 1;
108 		}
109 		/* ROM BARs are mapped into 32-bit memory space */
110 		if (dev->resource[PCI_ROM_RESOURCE].end != 0) {
111 			dev->resource[PCI_ROM_RESOURCE].flags |=
112 							IORESOURCE_ROM_ENABLE;
113 			has_mem = 1;
114 		}
115 		pci_bus_read_config_word(pbus, dev->devfn, PCI_COMMAND, &cmd);
116 		if (has_io && !(cmd & PCI_COMMAND_IO)) {
117 #ifdef CONFIG_PCI_DEBUG
118 			printk(KERN_INFO "LEONPCI: Enabling I/O for dev %s\n",
119 					 pci_name(dev));
120 #endif
121 			cmd |= PCI_COMMAND_IO;
122 			pci_bus_write_config_word(pbus, dev->devfn, PCI_COMMAND,
123 									cmd);
124 		}
125 		if (has_mem && !(cmd & PCI_COMMAND_MEMORY)) {
126 #ifdef CONFIG_PCI_DEBUG
127 			printk(KERN_INFO "LEONPCI: Enabling MEMORY for dev"
128 					 "%s\n", pci_name(dev));
129 #endif
130 			cmd |= PCI_COMMAND_MEMORY;
131 			pci_bus_write_config_word(pbus, dev->devfn, PCI_COMMAND,
132 									cmd);
133 		}
134 	}
135 }
136 
137 /*
138  * Other archs parse arguments here.
139  */
140 char * __devinit pcibios_setup(char *str)
141 {
142 	return str;
143 }
144 
145 resource_size_t pcibios_align_resource(void *data, const struct resource *res,
146 				resource_size_t size, resource_size_t align)
147 {
148 	return res->start;
149 }
150 
151 int pcibios_enable_device(struct pci_dev *dev, int mask)
152 {
153 	return pci_enable_resources(dev, mask);
154 }
155 
156 struct device_node *pci_device_to_OF_node(struct pci_dev *pdev)
157 {
158 	/*
159 	 * Currently the OpenBoot nodes are not connected with the PCI device,
160 	 * this is because the LEON PROM does not create PCI nodes. Eventually
161 	 * this will change and the same approach as pcic.c can be used to
162 	 * match PROM nodes with pci devices.
163 	 */
164 	return NULL;
165 }
166 EXPORT_SYMBOL(pci_device_to_OF_node);
167 
168 void __devinit pcibios_update_irq(struct pci_dev *dev, int irq)
169 {
170 #ifdef CONFIG_PCI_DEBUG
171 	printk(KERN_DEBUG "LEONPCI: Assigning IRQ %02d to %s\n", irq,
172 		pci_name(dev));
173 #endif
174 	pci_write_config_byte(dev, PCI_INTERRUPT_LINE, irq);
175 }
176 
177 /* in/out routines taken from pcic.c
178  *
179  * This probably belongs here rather than ioport.c because
180  * we do not want this crud linked into SBus kernels.
181  * Also, think for a moment about likes of floppy.c that
182  * include architecture specific parts. They may want to redefine ins/outs.
183  *
184  * We do not use horrible macros here because we want to
185  * advance pointer by sizeof(size).
186  */
187 void outsb(unsigned long addr, const void *src, unsigned long count)
188 {
189 	while (count) {
190 		count -= 1;
191 		outb(*(const char *)src, addr);
192 		src += 1;
193 		/* addr += 1; */
194 	}
195 }
196 EXPORT_SYMBOL(outsb);
197 
198 void outsw(unsigned long addr, const void *src, unsigned long count)
199 {
200 	while (count) {
201 		count -= 2;
202 		outw(*(const short *)src, addr);
203 		src += 2;
204 		/* addr += 2; */
205 	}
206 }
207 EXPORT_SYMBOL(outsw);
208 
209 void outsl(unsigned long addr, const void *src, unsigned long count)
210 {
211 	while (count) {
212 		count -= 4;
213 		outl(*(const long *)src, addr);
214 		src += 4;
215 		/* addr += 4; */
216 	}
217 }
218 EXPORT_SYMBOL(outsl);
219 
220 void insb(unsigned long addr, void *dst, unsigned long count)
221 {
222 	while (count) {
223 		count -= 1;
224 		*(unsigned char *)dst = inb(addr);
225 		dst += 1;
226 		/* addr += 1; */
227 	}
228 }
229 EXPORT_SYMBOL(insb);
230 
231 void insw(unsigned long addr, void *dst, unsigned long count)
232 {
233 	while (count) {
234 		count -= 2;
235 		*(unsigned short *)dst = inw(addr);
236 		dst += 2;
237 		/* addr += 2; */
238 	}
239 }
240 EXPORT_SYMBOL(insw);
241 
242 void insl(unsigned long addr, void *dst, unsigned long count)
243 {
244 	while (count) {
245 		count -= 4;
246 		/*
247 		 * XXX I am sure we are in for an unaligned trap here.
248 		 */
249 		*(unsigned long *)dst = inl(addr);
250 		dst += 4;
251 		/* addr += 4; */
252 	}
253 }
254 EXPORT_SYMBOL(insl);
255