xref: /linux/arch/mips/pci/pci-ip27.c (revision f3d9478b2ce468c3115b02ecae7e975990697f15)
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 extern unsigned int allocate_irqno(void);
20 
21 /*
22  * Max #PCI busses we can handle; ie, max #PCI bridges.
23  */
24 #define MAX_PCI_BUSSES		40
25 
26 /*
27  * Max #PCI devices (like scsi controllers) we handle on a bus.
28  */
29 #define MAX_DEVICES_PER_PCIBUS	8
30 
31 /*
32  * XXX: No kmalloc available when we do our crosstalk scan,
33  * 	we should try to move it later in the boot process.
34  */
35 static struct bridge_controller bridges[MAX_PCI_BUSSES];
36 
37 /*
38  * Translate from irq to software PCI bus number and PCI slot.
39  */
40 struct bridge_controller *irq_to_bridge[MAX_PCI_BUSSES * MAX_DEVICES_PER_PCIBUS];
41 int irq_to_slot[MAX_PCI_BUSSES * MAX_DEVICES_PER_PCIBUS];
42 
43 extern struct pci_ops bridge_pci_ops;
44 
45 int __init bridge_probe(nasid_t nasid, int widget_id, int masterwid)
46 {
47 	unsigned long offset = NODE_OFFSET(nasid);
48 	struct bridge_controller *bc;
49 	static int num_bridges = 0;
50 	bridge_t *bridge;
51 	int slot;
52 
53 	printk("a bridge\n");
54 
55 	/* XXX: kludge alert.. */
56 	if (!num_bridges)
57 		ioport_resource.end = ~0UL;
58 
59 	bc = &bridges[num_bridges];
60 
61 	bc->pc.pci_ops		= &bridge_pci_ops;
62 	bc->pc.mem_resource	= &bc->mem;
63 	bc->pc.io_resource	= &bc->io;
64 
65 	bc->pc.index		= num_bridges;
66 
67 	bc->mem.name		= "Bridge PCI MEM";
68 	bc->pc.mem_offset	= offset;
69 	bc->mem.start		= 0;
70 	bc->mem.end		= ~0UL;
71 	bc->mem.flags		= IORESOURCE_MEM;
72 
73 	bc->io.name		= "Bridge IO MEM";
74 	bc->pc.io_offset	= offset;
75 	bc->io.start		= 0UL;
76 	bc->io.end		= ~0UL;
77 	bc->io.flags		= IORESOURCE_IO;
78 
79 	bc->irq_cpu = smp_processor_id();
80 	bc->widget_id = widget_id;
81 	bc->nasid = nasid;
82 
83 	bc->baddr = (u64)masterwid << 60 | PCI64_ATTR_BAR;
84 
85 	/*
86 	 * point to this bridge
87 	 */
88 	bridge = (bridge_t *) RAW_NODE_SWIN_BASE(nasid, widget_id);
89 
90 	/*
91 	 * Clear all pending interrupts.
92 	 */
93 	bridge->b_int_rst_stat = BRIDGE_IRR_ALL_CLR;
94 
95 	/*
96 	 * Until otherwise set up, assume all interrupts are from slot 0
97 	 */
98 	bridge->b_int_device = 0x0;
99 
100 	/*
101 	 * swap pio's to pci mem and io space (big windows)
102 	 */
103 	bridge->b_wid_control |= BRIDGE_CTRL_IO_SWAP |
104 	                         BRIDGE_CTRL_MEM_SWAP;
105 
106 	/*
107 	 * Hmm...  IRIX sets additional bits in the address which
108 	 * are documented as reserved in the bridge docs.
109 	 */
110 	bridge->b_wid_int_upper = 0x8000 | (masterwid << 16);
111 	bridge->b_wid_int_lower = 0x01800090;	/* PI_INT_PEND_MOD off*/
112 	bridge->b_dir_map = (masterwid << 20);	/* DMA */
113 	bridge->b_int_enable = 0;
114 
115 	for (slot = 0; slot < 8; slot ++) {
116 		bridge->b_device[slot].reg |= BRIDGE_DEV_SWAP_DIR;
117 		bc->pci_int[slot] = -1;
118 	}
119 	bridge->b_wid_tflush;     /* wait until Bridge PIO complete */
120 
121 	bc->base = bridge;
122 
123 	register_pci_controller(&bc->pc);
124 
125 	num_bridges++;
126 
127 	return 0;
128 }
129 
130 /*
131  * All observed requests have pin == 1. We could have a global here, that
132  * gets incremented and returned every time - unfortunately, pci_map_irq
133  * may be called on the same device over and over, and need to return the
134  * same value. On O2000, pin can be 0 or 1, and PCI slots can be [0..7].
135  *
136  * A given PCI device, in general, should be able to intr any of the cpus
137  * on any one of the hubs connected to its xbow.
138  */
139 int __devinit pcibios_map_irq(struct pci_dev *dev, u8 slot, u8 pin)
140 {
141 	struct bridge_controller *bc = BRIDGE_CONTROLLER(dev->bus);
142 	int irq = bc->pci_int[slot];
143 
144 	if (irq == -1) {
145 		irq = bc->pci_int[slot] = request_bridge_irq(bc);
146 		if (irq < 0)
147 			panic("Can't allocate interrupt for PCI device %s\n",
148 			      pci_name(dev));
149 	}
150 
151 	irq_to_bridge[irq] = bc;
152 	irq_to_slot[irq] = slot;
153 
154 	return irq;
155 }
156 
157 /* Do platform specific device initialization at pci_enable_device() time */
158 int pcibios_plat_dev_init(struct pci_dev *dev)
159 {
160 	return 0;
161 }
162 
163 /*
164  * Device might live on a subordinate PCI bus.  XXX Walk up the chain of buses
165  * to find the slot number in sense of the bridge device register.
166  * XXX This also means multiple devices might rely on conflicting bridge
167  * settings.
168  */
169 
170 static inline void pci_disable_swapping(struct pci_dev *dev)
171 {
172 	struct bridge_controller *bc = BRIDGE_CONTROLLER(dev->bus);
173 	bridge_t *bridge = bc->base;
174 	int slot = PCI_SLOT(dev->devfn);
175 
176 	/* Turn off byte swapping */
177 	bridge->b_device[slot].reg &= ~BRIDGE_DEV_SWAP_DIR;
178 	bridge->b_widget.w_tflush;	/* Flush */
179 }
180 
181 static inline void pci_enable_swapping(struct pci_dev *dev)
182 {
183 	struct bridge_controller *bc = BRIDGE_CONTROLLER(dev->bus);
184 	bridge_t *bridge = bc->base;
185 	int slot = PCI_SLOT(dev->devfn);
186 
187 	/* Turn on byte swapping */
188 	bridge->b_device[slot].reg |= BRIDGE_DEV_SWAP_DIR;
189 	bridge->b_widget.w_tflush;	/* Flush */
190 }
191 
192 static void __init pci_fixup_ioc3(struct pci_dev *d)
193 {
194 	pci_disable_swapping(d);
195 }
196 
197 int pcibus_to_node(struct pci_bus *bus)
198 {
199 	struct bridge_controller *bc = BRIDGE_CONTROLLER(bus);
200 
201 	return bc->nasid;
202 }
203 
204 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_SGI, PCI_DEVICE_ID_SGI_IOC3,
205 	pci_fixup_ioc3);
206