xref: /linux/arch/sparc/kernel/leon_pci.c (revision e9e8bcb8178e197d889ec31e79fa1ddc1732c8f9)
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 <asm/leon.h>
13 #include <asm/leon_pci.h>
14 
15 /* The LEON architecture does not rely on a BIOS or bootloader to setup
16  * PCI for us. The Linux generic routines are used to setup resources,
17  * reset values of confuration-space registers settings ae preseved.
18  */
19 void leon_pci_init(struct platform_device *ofdev, struct leon_pci_info *info)
20 {
21 	struct pci_bus *root_bus;
22 
23 	root_bus = pci_scan_bus_parented(&ofdev->dev, 0, info->ops, info);
24 	if (root_bus) {
25 		root_bus->resource[0] = &info->io_space;
26 		root_bus->resource[1] = &info->mem_space;
27 		root_bus->resource[2] = NULL;
28 
29 		/* Init all PCI devices into PCI tree */
30 		pci_bus_add_devices(root_bus);
31 
32 		/* Setup IRQs of all devices using custom routines */
33 		pci_fixup_irqs(pci_common_swizzle, info->map_irq);
34 
35 		/* Assign devices with resources */
36 		pci_assign_unassigned_resources();
37 	}
38 }
39 
40 /* PCI Memory and Prefetchable Memory is direct-mapped. However I/O Space is
41  * accessed through a Window which is translated to low 64KB in PCI space, the
42  * first 4KB is not used so 60KB is available.
43  *
44  * This function is used by generic code to translate resource addresses into
45  * PCI addresses.
46  */
47 void pcibios_resource_to_bus(struct pci_dev *dev, struct pci_bus_region *region,
48 			     struct resource *res)
49 {
50 	struct leon_pci_info *info = dev->bus->sysdata;
51 
52 	region->start = res->start;
53 	region->end = res->end;
54 
55 	if (res->flags & IORESOURCE_IO) {
56 		region->start -= (info->io_space.start - 0x1000);
57 		region->end -= (info->io_space.start - 0x1000);
58 	}
59 }
60 EXPORT_SYMBOL(pcibios_resource_to_bus);
61 
62 /* see pcibios_resource_to_bus() comment */
63 void pcibios_bus_to_resource(struct pci_dev *dev, struct resource *res,
64 			     struct pci_bus_region *region)
65 {
66 	struct leon_pci_info *info = dev->bus->sysdata;
67 
68 	res->start = region->start;
69 	res->end = region->end;
70 
71 	if (res->flags & IORESOURCE_IO) {
72 		res->start += (info->io_space.start - 0x1000);
73 		res->end += (info->io_space.start - 0x1000);
74 	}
75 }
76 EXPORT_SYMBOL(pcibios_bus_to_resource);
77 
78 void __devinit pcibios_fixup_bus(struct pci_bus *pbus)
79 {
80 	struct leon_pci_info *info = pbus->sysdata;
81 	struct pci_dev *dev;
82 	int i, has_io, has_mem;
83 	u16 cmd;
84 
85 	/* Generic PCI bus probing sets these to point at
86 	 * &io{port,mem}_resouce which is wrong for us.
87 	 */
88 	if (pbus->self == NULL) {
89 		pbus->resource[0] = &info->io_space;
90 		pbus->resource[1] = &info->mem_space;
91 		pbus->resource[2] = NULL;
92 	}
93 
94 	list_for_each_entry(dev, &pbus->devices, bus_list) {
95 		/*
96 		 * We can not rely on that the bootloader has enabled I/O
97 		 * or memory access to PCI devices. Instead we enable it here
98 		 * if the device has BARs of respective type.
99 		 */
100 		has_io = has_mem = 0;
101 		for (i = 0; i < PCI_ROM_RESOURCE; i++) {
102 			unsigned long f = dev->resource[i].flags;
103 			if (f & IORESOURCE_IO)
104 				has_io = 1;
105 			else if (f & IORESOURCE_MEM)
106 				has_mem = 1;
107 		}
108 		/* ROM BARs are mapped into 32-bit memory space */
109 		if (dev->resource[PCI_ROM_RESOURCE].end != 0) {
110 			dev->resource[PCI_ROM_RESOURCE].flags |=
111 							IORESOURCE_ROM_ENABLE;
112 			has_mem = 1;
113 		}
114 		pci_bus_read_config_word(pbus, dev->devfn, PCI_COMMAND, &cmd);
115 		if (has_io && !(cmd & PCI_COMMAND_IO)) {
116 #ifdef CONFIG_PCI_DEBUG
117 			printk(KERN_INFO "LEONPCI: Enabling I/O for dev %s\n",
118 					 pci_name(dev));
119 #endif
120 			cmd |= PCI_COMMAND_IO;
121 			pci_bus_write_config_word(pbus, dev->devfn, PCI_COMMAND,
122 									cmd);
123 		}
124 		if (has_mem && !(cmd & PCI_COMMAND_MEMORY)) {
125 #ifdef CONFIG_PCI_DEBUG
126 			printk(KERN_INFO "LEONPCI: Enabling MEMORY for dev"
127 					 "%s\n", pci_name(dev));
128 #endif
129 			cmd |= PCI_COMMAND_MEMORY;
130 			pci_bus_write_config_word(pbus, dev->devfn, PCI_COMMAND,
131 									cmd);
132 		}
133 	}
134 }
135 
136 /*
137  * Other archs parse arguments here.
138  */
139 char * __devinit pcibios_setup(char *str)
140 {
141 	return str;
142 }
143 
144 resource_size_t pcibios_align_resource(void *data, const struct resource *res,
145 				resource_size_t size, resource_size_t align)
146 {
147 	return res->start;
148 }
149 
150 int pcibios_enable_device(struct pci_dev *dev, int mask)
151 {
152 	return pci_enable_resources(dev, mask);
153 }
154 
155 struct device_node *pci_device_to_OF_node(struct pci_dev *pdev)
156 {
157 	/*
158 	 * Currently the OpenBoot nodes are not connected with the PCI device,
159 	 * this is because the LEON PROM does not create PCI nodes. Eventually
160 	 * this will change and the same approach as pcic.c can be used to
161 	 * match PROM nodes with pci devices.
162 	 */
163 	return NULL;
164 }
165 EXPORT_SYMBOL(pci_device_to_OF_node);
166 
167 void __devinit pcibios_update_irq(struct pci_dev *dev, int irq)
168 {
169 #ifdef CONFIG_PCI_DEBUG
170 	printk(KERN_DEBUG "LEONPCI: Assigning IRQ %02d to %s\n", irq,
171 		pci_name(dev));
172 #endif
173 	pci_write_config_byte(dev, PCI_INTERRUPT_LINE, irq);
174 }
175 
176 /* in/out routines taken from pcic.c
177  *
178  * This probably belongs here rather than ioport.c because
179  * we do not want this crud linked into SBus kernels.
180  * Also, think for a moment about likes of floppy.c that
181  * include architecture specific parts. They may want to redefine ins/outs.
182  *
183  * We do not use horrible macros here because we want to
184  * advance pointer by sizeof(size).
185  */
186 void outsb(unsigned long addr, const void *src, unsigned long count)
187 {
188 	while (count) {
189 		count -= 1;
190 		outb(*(const char *)src, addr);
191 		src += 1;
192 		/* addr += 1; */
193 	}
194 }
195 EXPORT_SYMBOL(outsb);
196 
197 void outsw(unsigned long addr, const void *src, unsigned long count)
198 {
199 	while (count) {
200 		count -= 2;
201 		outw(*(const short *)src, addr);
202 		src += 2;
203 		/* addr += 2; */
204 	}
205 }
206 EXPORT_SYMBOL(outsw);
207 
208 void outsl(unsigned long addr, const void *src, unsigned long count)
209 {
210 	while (count) {
211 		count -= 4;
212 		outl(*(const long *)src, addr);
213 		src += 4;
214 		/* addr += 4; */
215 	}
216 }
217 EXPORT_SYMBOL(outsl);
218 
219 void insb(unsigned long addr, void *dst, unsigned long count)
220 {
221 	while (count) {
222 		count -= 1;
223 		*(unsigned char *)dst = inb(addr);
224 		dst += 1;
225 		/* addr += 1; */
226 	}
227 }
228 EXPORT_SYMBOL(insb);
229 
230 void insw(unsigned long addr, void *dst, unsigned long count)
231 {
232 	while (count) {
233 		count -= 2;
234 		*(unsigned short *)dst = inw(addr);
235 		dst += 2;
236 		/* addr += 2; */
237 	}
238 }
239 EXPORT_SYMBOL(insw);
240 
241 void insl(unsigned long addr, void *dst, unsigned long count)
242 {
243 	while (count) {
244 		count -= 4;
245 		/*
246 		 * XXX I am sure we are in for an unaligned trap here.
247 		 */
248 		*(unsigned long *)dst = inl(addr);
249 		dst += 4;
250 		/* addr += 4; */
251 	}
252 }
253 EXPORT_SYMBOL(insl);
254