xref: /openbmc/linux/arch/mips/pci/pci-ip27.c (revision f42b3800)
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/init.h>
11 #include <linux/kernel.h>
12 #include <linux/pci.h>
13 #include <asm/sn/arch.h>
14 #include <asm/pci/bridge.h>
15 #include <asm/paccess.h>
16 #include <asm/sn/intr.h>
17 #include <asm/sn/sn0/hub.h>
18 
19 /*
20  * Max #PCI busses we can handle; ie, max #PCI bridges.
21  */
22 #define MAX_PCI_BUSSES		40
23 
24 /*
25  * Max #PCI devices (like scsi controllers) we handle on a bus.
26  */
27 #define MAX_DEVICES_PER_PCIBUS	8
28 
29 /*
30  * XXX: No kmalloc available when we do our crosstalk scan,
31  * 	we should try to move it later in the boot process.
32  */
33 static struct bridge_controller bridges[MAX_PCI_BUSSES];
34 
35 /*
36  * Translate from irq to software PCI bus number and PCI slot.
37  */
38 struct bridge_controller *irq_to_bridge[MAX_PCI_BUSSES * MAX_DEVICES_PER_PCIBUS];
39 int irq_to_slot[MAX_PCI_BUSSES * MAX_DEVICES_PER_PCIBUS];
40 
41 extern struct pci_ops bridge_pci_ops;
42 
43 int __cpuinit bridge_probe(nasid_t nasid, int widget_id, int masterwid)
44 {
45 	unsigned long offset = NODE_OFFSET(nasid);
46 	struct bridge_controller *bc;
47 	static int num_bridges = 0;
48 	bridge_t *bridge;
49 	int slot;
50 
51 	printk("a bridge\n");
52 
53 	/* XXX: kludge alert.. */
54 	if (!num_bridges)
55 		ioport_resource.end = ~0UL;
56 
57 	bc = &bridges[num_bridges];
58 
59 	bc->pc.pci_ops		= &bridge_pci_ops;
60 	bc->pc.mem_resource	= &bc->mem;
61 	bc->pc.io_resource	= &bc->io;
62 
63 	bc->pc.index		= num_bridges;
64 
65 	bc->mem.name		= "Bridge PCI MEM";
66 	bc->pc.mem_offset	= offset;
67 	bc->mem.start		= 0;
68 	bc->mem.end		= ~0UL;
69 	bc->mem.flags		= IORESOURCE_MEM;
70 
71 	bc->io.name		= "Bridge IO MEM";
72 	bc->pc.io_offset	= offset;
73 	bc->io.start		= 0UL;
74 	bc->io.end		= ~0UL;
75 	bc->io.flags		= IORESOURCE_IO;
76 
77 	bc->irq_cpu = smp_processor_id();
78 	bc->widget_id = widget_id;
79 	bc->nasid = nasid;
80 
81 	bc->baddr = (u64)masterwid << 60 | PCI64_ATTR_BAR;
82 
83 	/*
84 	 * point to this bridge
85 	 */
86 	bridge = (bridge_t *) RAW_NODE_SWIN_BASE(nasid, widget_id);
87 
88 	/*
89 	 * Clear all pending interrupts.
90 	 */
91 	bridge->b_int_rst_stat = BRIDGE_IRR_ALL_CLR;
92 
93 	/*
94 	 * Until otherwise set up, assume all interrupts are from slot 0
95 	 */
96 	bridge->b_int_device = 0x0;
97 
98 	/*
99 	 * swap pio's to pci mem and io space (big windows)
100 	 */
101 	bridge->b_wid_control |= BRIDGE_CTRL_IO_SWAP |
102 	                         BRIDGE_CTRL_MEM_SWAP;
103 
104 	/*
105 	 * Hmm...  IRIX sets additional bits in the address which
106 	 * are documented as reserved in the bridge docs.
107 	 */
108 	bridge->b_wid_int_upper = 0x8000 | (masterwid << 16);
109 	bridge->b_wid_int_lower = 0x01800090;	/* PI_INT_PEND_MOD off*/
110 	bridge->b_dir_map = (masterwid << 20);	/* DMA */
111 	bridge->b_int_enable = 0;
112 
113 	for (slot = 0; slot < 8; slot ++) {
114 		bridge->b_device[slot].reg |= BRIDGE_DEV_SWAP_DIR;
115 		bc->pci_int[slot] = -1;
116 	}
117 	bridge->b_wid_tflush;     /* wait until Bridge PIO complete */
118 
119 	bc->base = bridge;
120 
121 	register_pci_controller(&bc->pc);
122 
123 	num_bridges++;
124 
125 	return 0;
126 }
127 
128 /*
129  * All observed requests have pin == 1. We could have a global here, that
130  * gets incremented and returned every time - unfortunately, pci_map_irq
131  * may be called on the same device over and over, and need to return the
132  * same value. On O2000, pin can be 0 or 1, and PCI slots can be [0..7].
133  *
134  * A given PCI device, in general, should be able to intr any of the cpus
135  * on any one of the hubs connected to its xbow.
136  */
137 int __devinit pcibios_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
138 {
139 	struct bridge_controller *bc = BRIDGE_CONTROLLER(dev->bus);
140 	int irq = bc->pci_int[slot];
141 
142 	if (irq == -1) {
143 		irq = bc->pci_int[slot] = request_bridge_irq(bc);
144 		if (irq < 0)
145 			panic("Can't allocate interrupt for PCI device %s\n",
146 			      pci_name(dev));
147 	}
148 
149 	irq_to_bridge[irq] = bc;
150 	irq_to_slot[irq] = slot;
151 
152 	return irq;
153 }
154 
155 /* Do platform specific device initialization at pci_enable_device() time */
156 int pcibios_plat_dev_init(struct pci_dev *dev)
157 {
158 	return 0;
159 }
160 
161 /*
162  * Device might live on a subordinate PCI bus.  XXX Walk up the chain of buses
163  * to find the slot number in sense of the bridge device register.
164  * XXX This also means multiple devices might rely on conflicting bridge
165  * settings.
166  */
167 
168 static inline void pci_disable_swapping(struct pci_dev *dev)
169 {
170 	struct bridge_controller *bc = BRIDGE_CONTROLLER(dev->bus);
171 	bridge_t *bridge = bc->base;
172 	int slot = PCI_SLOT(dev->devfn);
173 
174 	/* Turn off byte swapping */
175 	bridge->b_device[slot].reg &= ~BRIDGE_DEV_SWAP_DIR;
176 	bridge->b_widget.w_tflush;	/* Flush */
177 }
178 
179 static inline void pci_enable_swapping(struct pci_dev *dev)
180 {
181 	struct bridge_controller *bc = BRIDGE_CONTROLLER(dev->bus);
182 	bridge_t *bridge = bc->base;
183 	int slot = PCI_SLOT(dev->devfn);
184 
185 	/* Turn on byte swapping */
186 	bridge->b_device[slot].reg |= BRIDGE_DEV_SWAP_DIR;
187 	bridge->b_widget.w_tflush;	/* Flush */
188 }
189 
190 static void __init pci_fixup_ioc3(struct pci_dev *d)
191 {
192 	pci_disable_swapping(d);
193 }
194 
195 int pcibus_to_node(struct pci_bus *bus)
196 {
197 	struct bridge_controller *bc = BRIDGE_CONTROLLER(bus);
198 
199 	return bc->nasid;
200 }
201 
202 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_SGI, PCI_DEVICE_ID_SGI_IOC3,
203 	pci_fixup_ioc3);
204