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1// SPDX-License-Identifier: GPL-2.0
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>
13#include <linux/export.h>
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,
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.
24 */
25void leon_pci_init(struct platform_device *ofdev, struct leon_pci_info *info)
26{
27 LIST_HEAD(resources);
28 struct pci_bus *root_bus;
29 struct pci_host_bridge *bridge;
30 int ret;
31
32 bridge = pci_alloc_host_bridge(0);
33 if (!bridge)
34 return;
35
36 pci_add_resource_offset(&resources, &info->io_space,
37 info->io_space.start - 0x1000);
38 pci_add_resource(&resources, &info->mem_space);
39 info->busn.flags = IORESOURCE_BUS;
40 pci_add_resource(&resources, &info->busn);
41
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);
53 return;
54 }
55
56 root_bus = bridge->bus;
57
58 /* Assign devices with resources */
59 pci_assign_unassigned_resources();
60 pci_bus_add_devices(root_bus);
61}
62
63int pcibios_enable_device(struct pci_dev *dev, int mask)
64{
65 u16 cmd, oldcmd;
66 int i;
67
68 pci_read_config_word(dev, PCI_COMMAND, &cmd);
69 oldcmd = cmd;
70
71 for (i = 0; i < PCI_NUM_RESOURCES; i++) {
72 struct resource *res = &dev->resource[i];
73
74 /* Only set up the requested stuff */
75 if (!(mask & (1<<i)))
76 continue;
77
78 if (res->flags & IORESOURCE_IO)
79 cmd |= PCI_COMMAND_IO;
80 if (res->flags & IORESOURCE_MEM)
81 cmd |= PCI_COMMAND_MEMORY;
82 }
83
84 if (cmd != oldcmd) {
85 pci_info(dev, "enabling device (%04x -> %04x)\n", oldcmd, cmd);
86 pci_write_config_word(dev, PCI_COMMAND, cmd);
87 }
88 return 0;
89}
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 */
19void 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 */
47void 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}
60EXPORT_SYMBOL(pcibios_resource_to_bus);
61
62/* see pcibios_resource_to_bus() comment */
63void 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}
76EXPORT_SYMBOL(pcibios_bus_to_resource);
77
78void __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 */
139char * __devinit pcibios_setup(char *str)
140{
141 return str;
142}
143
144resource_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
150int pcibios_enable_device(struct pci_dev *dev, int mask)
151{
152 return pci_enable_resources(dev, mask);
153}
154
155struct 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}
165EXPORT_SYMBOL(pci_device_to_OF_node);
166
167void __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 */
186void 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}
195EXPORT_SYMBOL(outsb);
196
197void 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}
206EXPORT_SYMBOL(outsw);
207
208void 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}
217EXPORT_SYMBOL(outsl);
218
219void 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}
228EXPORT_SYMBOL(insb);
229
230void 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}
239EXPORT_SYMBOL(insw);
240
241void 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}
253EXPORT_SYMBOL(insl);