xref: /openbmc/linux/arch/mips/pci/pci-ip27.c (revision e2c75e76)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 2003 Christoph Hellwig (hch@lst.de)
7  * Copyright (C) 1999, 2000, 04 Ralf Baechle (ralf@linux-mips.org)
8  * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
9  */
10 #include <linux/kernel.h>
11 #include <linux/export.h>
12 #include <linux/pci.h>
13 #include <linux/smp.h>
14 #include <asm/sn/arch.h>
15 #include <asm/pci/bridge.h>
16 #include <asm/paccess.h>
17 #include <asm/sn/intr.h>
18 #include <asm/sn/sn0/hub.h>
19 
20 /*
21  * Max #PCI busses we can handle; ie, max #PCI bridges.
22  */
23 #define MAX_PCI_BUSSES		40
24 
25 /*
26  * Max #PCI devices (like scsi controllers) we handle on a bus.
27  */
28 #define MAX_DEVICES_PER_PCIBUS	8
29 
30 /*
31  * XXX: No kmalloc available when we do our crosstalk scan,
32  *	we should try to move it later in the boot process.
33  */
34 static struct bridge_controller bridges[MAX_PCI_BUSSES];
35 
36 /*
37  * Translate from irq to software PCI bus number and PCI slot.
38  */
39 struct bridge_controller *irq_to_bridge[MAX_PCI_BUSSES * MAX_DEVICES_PER_PCIBUS];
40 int irq_to_slot[MAX_PCI_BUSSES * MAX_DEVICES_PER_PCIBUS];
41 
42 extern struct pci_ops bridge_pci_ops;
43 
44 int bridge_probe(nasid_t nasid, int widget_id, int masterwid)
45 {
46 	unsigned long offset = NODE_OFFSET(nasid);
47 	struct bridge_controller *bc;
48 	static int num_bridges = 0;
49 	bridge_t *bridge;
50 	int slot;
51 
52 	pci_set_flags(PCI_PROBE_ONLY);
53 
54 	printk("a bridge\n");
55 
56 	/* XXX: kludge alert.. */
57 	if (!num_bridges)
58 		ioport_resource.end = ~0UL;
59 
60 	bc = &bridges[num_bridges];
61 
62 	bc->pc.pci_ops		= &bridge_pci_ops;
63 	bc->pc.mem_resource	= &bc->mem;
64 	bc->pc.io_resource	= &bc->io;
65 
66 	bc->pc.index		= num_bridges;
67 
68 	bc->mem.name		= "Bridge PCI MEM";
69 	bc->pc.mem_offset	= offset;
70 	bc->mem.start		= 0;
71 	bc->mem.end		= ~0UL;
72 	bc->mem.flags		= IORESOURCE_MEM;
73 
74 	bc->io.name		= "Bridge IO MEM";
75 	bc->pc.io_offset	= offset;
76 	bc->io.start		= 0UL;
77 	bc->io.end		= ~0UL;
78 	bc->io.flags		= IORESOURCE_IO;
79 
80 	bc->irq_cpu = smp_processor_id();
81 	bc->widget_id = widget_id;
82 	bc->nasid = nasid;
83 
84 	bc->baddr = (u64)masterwid << 60 | PCI64_ATTR_BAR;
85 
86 	/*
87 	 * point to this bridge
88 	 */
89 	bridge = (bridge_t *) RAW_NODE_SWIN_BASE(nasid, widget_id);
90 
91 	/*
92 	 * Clear all pending interrupts.
93 	 */
94 	bridge->b_int_rst_stat = BRIDGE_IRR_ALL_CLR;
95 
96 	/*
97 	 * Until otherwise set up, assume all interrupts are from slot 0
98 	 */
99 	bridge->b_int_device = 0x0;
100 
101 	/*
102 	 * swap pio's to pci mem and io space (big windows)
103 	 */
104 	bridge->b_wid_control |= BRIDGE_CTRL_IO_SWAP |
105 				 BRIDGE_CTRL_MEM_SWAP;
106 #ifdef CONFIG_PAGE_SIZE_4KB
107 	bridge->b_wid_control &= ~BRIDGE_CTRL_PAGE_SIZE;
108 #else /* 16kB or larger */
109 	bridge->b_wid_control |= BRIDGE_CTRL_PAGE_SIZE;
110 #endif
111 
112 	/*
113 	 * Hmm...  IRIX sets additional bits in the address which
114 	 * are documented as reserved in the bridge docs.
115 	 */
116 	bridge->b_wid_int_upper = 0x8000 | (masterwid << 16);
117 	bridge->b_wid_int_lower = 0x01800090;	/* PI_INT_PEND_MOD off*/
118 	bridge->b_dir_map = (masterwid << 20);	/* DMA */
119 	bridge->b_int_enable = 0;
120 
121 	for (slot = 0; slot < 8; slot ++) {
122 		bridge->b_device[slot].reg |= BRIDGE_DEV_SWAP_DIR;
123 		bc->pci_int[slot] = -1;
124 	}
125 	bridge->b_wid_tflush;	  /* wait until Bridge PIO complete */
126 
127 	bc->base = bridge;
128 
129 	register_pci_controller(&bc->pc);
130 
131 	num_bridges++;
132 
133 	return 0;
134 }
135 
136 /*
137  * All observed requests have pin == 1. We could have a global here, that
138  * gets incremented and returned every time - unfortunately, pci_map_irq
139  * may be called on the same device over and over, and need to return the
140  * same value. On O2000, pin can be 0 or 1, and PCI slots can be [0..7].
141  *
142  * A given PCI device, in general, should be able to intr any of the cpus
143  * on any one of the hubs connected to its xbow.
144  */
145 int pcibios_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
146 {
147 	return 0;
148 }
149 
150 static inline struct pci_dev *bridge_root_dev(struct pci_dev *dev)
151 {
152 	while (dev->bus->parent) {
153 		/* Move up the chain of bridges. */
154 		dev = dev->bus->self;
155 	}
156 
157 	return dev;
158 }
159 
160 /* Do platform specific device initialization at pci_enable_device() time */
161 int pcibios_plat_dev_init(struct pci_dev *dev)
162 {
163 	struct bridge_controller *bc = BRIDGE_CONTROLLER(dev->bus);
164 	struct pci_dev *rdev = bridge_root_dev(dev);
165 	int slot = PCI_SLOT(rdev->devfn);
166 	int irq;
167 
168 	irq = bc->pci_int[slot];
169 	if (irq == -1) {
170 		irq = request_bridge_irq(bc);
171 		if (irq < 0)
172 			return irq;
173 
174 		bc->pci_int[slot] = irq;
175 	}
176 
177 	irq_to_bridge[irq] = bc;
178 	irq_to_slot[irq] = slot;
179 
180 	dev->irq = irq;
181 
182 	return 0;
183 }
184 
185 /*
186  * Device might live on a subordinate PCI bus.	XXX Walk up the chain of buses
187  * to find the slot number in sense of the bridge device register.
188  * XXX This also means multiple devices might rely on conflicting bridge
189  * settings.
190  */
191 
192 static inline void pci_disable_swapping(struct pci_dev *dev)
193 {
194 	struct bridge_controller *bc = BRIDGE_CONTROLLER(dev->bus);
195 	bridge_t *bridge = bc->base;
196 	int slot = PCI_SLOT(dev->devfn);
197 
198 	/* Turn off byte swapping */
199 	bridge->b_device[slot].reg &= ~BRIDGE_DEV_SWAP_DIR;
200 	bridge->b_widget.w_tflush;	/* Flush */
201 }
202 
203 static inline void pci_enable_swapping(struct pci_dev *dev)
204 {
205 	struct bridge_controller *bc = BRIDGE_CONTROLLER(dev->bus);
206 	bridge_t *bridge = bc->base;
207 	int slot = PCI_SLOT(dev->devfn);
208 
209 	/* Turn on byte swapping */
210 	bridge->b_device[slot].reg |= BRIDGE_DEV_SWAP_DIR;
211 	bridge->b_widget.w_tflush;	/* Flush */
212 }
213 
214 static void pci_fixup_ioc3(struct pci_dev *d)
215 {
216 	pci_disable_swapping(d);
217 }
218 
219 #ifdef CONFIG_NUMA
220 int pcibus_to_node(struct pci_bus *bus)
221 {
222 	struct bridge_controller *bc = BRIDGE_CONTROLLER(bus);
223 
224 	return bc->nasid;
225 }
226 EXPORT_SYMBOL(pcibus_to_node);
227 #endif /* CONFIG_NUMA */
228 
229 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_SGI, PCI_DEVICE_ID_SGI_IOC3,
230 	pci_fixup_ioc3);
231