xref: /linux/arch/parisc/kernel/pci.c (revision 9036bd0efcb6162a77f3bf9bacbafba7686c7275)
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) 1997, 1998 Ralf Baechle
7  * Copyright (C) 1999 SuSE GmbH
8  * Copyright (C) 1999-2001 Hewlett-Packard Company
9  * Copyright (C) 1999-2001 Grant Grundler
10  */
11 #include <linux/align.h>
12 #include <linux/eisa.h>
13 #include <linux/init.h>
14 #include <linux/module.h>
15 #include <linux/kernel.h>
16 #include <linux/pci.h>
17 #include <linux/types.h>
18 
19 #include <asm/io.h>
20 #include <asm/superio.h>
21 
22 #define DEBUG_RESOURCES 0
23 #define DEBUG_CONFIG 0
24 
25 #if DEBUG_CONFIG
26 # define DBGC(x...)	printk(KERN_DEBUG x)
27 #else
28 # define DBGC(x...)
29 #endif
30 
31 
32 #if DEBUG_RESOURCES
33 #define DBG_RES(x...)	printk(KERN_DEBUG x)
34 #else
35 #define DBG_RES(x...)
36 #endif
37 
38 struct pci_port_ops *pci_port __ro_after_init;
39 struct pci_bios_ops *pci_bios __ro_after_init;
40 
41 static int pci_hba_count __ro_after_init;
42 
43 /* parisc_pci_hba used by pci_port->in/out() ops to lookup bus data.  */
44 #define PCI_HBA_MAX 32
45 static struct pci_hba_data *parisc_pci_hba[PCI_HBA_MAX] __ro_after_init;
46 
47 
48 /********************************************************************
49 **
50 ** I/O port space support
51 **
52 *********************************************************************/
53 
54 /* EISA port numbers and PCI port numbers share the same interface.  Some
55  * machines have both EISA and PCI adapters installed.  Rather than turn
56  * pci_port into an array, we reserve bus 0 for EISA and call the EISA
57  * routines if the access is to a port on bus 0.  We don't want to fix
58  * EISA and ISA drivers which assume port space is <= 0xffff.
59  */
60 
61 #ifdef CONFIG_EISA
62 #define EISA_IN(size) if (EISA_bus && (b == 0)) return eisa_in##size(addr)
63 #define EISA_OUT(size) if (EISA_bus && (b == 0)) return eisa_out##size(d, addr)
64 #else
65 #define EISA_IN(size)
66 #define EISA_OUT(size)
67 #endif
68 
69 #define PCI_PORT_IN(type, size) \
70 u##size in##type (int addr) \
71 { \
72 	int b = PCI_PORT_HBA(addr); \
73 	EISA_IN(size); \
74 	if (!parisc_pci_hba[b]) return (u##size) -1; \
75 	return pci_port->in##type(parisc_pci_hba[b], PCI_PORT_ADDR(addr)); \
76 } \
77 EXPORT_SYMBOL(in##type);
78 
79 PCI_PORT_IN(b,  8)
80 PCI_PORT_IN(w, 16)
81 PCI_PORT_IN(l, 32)
82 
83 
84 #define PCI_PORT_OUT(type, size) \
85 void out##type (u##size d, int addr) \
86 { \
87 	int b = PCI_PORT_HBA(addr); \
88 	EISA_OUT(size); \
89 	if (!parisc_pci_hba[b]) return; \
90 	pci_port->out##type(parisc_pci_hba[b], PCI_PORT_ADDR(addr), d); \
91 } \
92 EXPORT_SYMBOL(out##type);
93 
94 PCI_PORT_OUT(b,  8)
95 PCI_PORT_OUT(w, 16)
96 PCI_PORT_OUT(l, 32)
97 
98 
99 
100 /*
101  * BIOS32 replacement.
102  */
103 static int __init pcibios_init(void)
104 {
105 	if (!pci_bios)
106 		return -1;
107 
108 	if (pci_bios->init) {
109 		pci_bios->init();
110 	} else {
111 		printk(KERN_WARNING "pci_bios != NULL but init() is!\n");
112 	}
113 
114 	/* Set the CLS for PCI as early as possible. */
115 	pci_cache_line_size = pci_dfl_cache_line_size;
116 
117 	return 0;
118 }
119 
120 
121 /* Called from pci_do_scan_bus() *after* walking a bus but before walking PPBs. */
122 void pcibios_fixup_bus(struct pci_bus *bus)
123 {
124 	if (pci_bios->fixup_bus) {
125 		pci_bios->fixup_bus(bus);
126 	} else {
127 		printk(KERN_WARNING "pci_bios != NULL but fixup_bus() is!\n");
128 	}
129 }
130 
131 
132 /*
133  * Called by pci_set_master() - a driver interface.
134  *
135  * Legacy PDC guarantees to set:
136  *	Map Memory BAR's into PA IO space.
137  *	Map Expansion ROM BAR into one common PA IO space per bus.
138  *	Map IO BAR's into PCI IO space.
139  *	Command (see below)
140  *	Cache Line Size
141  *	Latency Timer
142  *	Interrupt Line
143  *	PPB: secondary latency timer, io/mmio base/limit,
144  *		bus numbers, bridge control
145  *
146  */
147 void pcibios_set_master(struct pci_dev *dev)
148 {
149 	u8 lat;
150 
151 	/* If someone already mucked with this, don't touch it. */
152 	pci_read_config_byte(dev, PCI_LATENCY_TIMER, &lat);
153 	if (lat >= 16) return;
154 
155 	/*
156 	** HP generally has fewer devices on the bus than other architectures.
157 	** upper byte is PCI_LATENCY_TIMER.
158 	*/
159 	pci_write_config_word(dev, PCI_CACHE_LINE_SIZE,
160 			      (0x80 << 8) | pci_cache_line_size);
161 }
162 
163 /*
164  * pcibios_init_bridge() initializes cache line and default latency
165  * for pci controllers and pci-pci bridges
166  */
167 void __ref pcibios_init_bridge(struct pci_dev *dev)
168 {
169 	unsigned short bridge_ctl, bridge_ctl_new;
170 
171 	/* We deal only with pci controllers and pci-pci bridges. */
172 	if (!dev || (dev->class >> 8) != PCI_CLASS_BRIDGE_PCI)
173 		return;
174 
175 	/* PCI-PCI bridge - set the cache line and default latency
176 	 * (32) for primary and secondary buses.
177 	 */
178 	pci_write_config_byte(dev, PCI_SEC_LATENCY_TIMER, 32);
179 
180 	pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &bridge_ctl);
181 
182 	bridge_ctl_new = bridge_ctl | PCI_BRIDGE_CTL_PARITY |
183 		PCI_BRIDGE_CTL_SERR | PCI_BRIDGE_CTL_MASTER_ABORT;
184 	dev_info(&dev->dev, "Changing bridge control from 0x%08x to 0x%08x\n",
185 		bridge_ctl, bridge_ctl_new);
186 
187 	pci_write_config_word(dev, PCI_BRIDGE_CONTROL, bridge_ctl_new);
188 }
189 
190 /*
191  * pcibios align resources() is called every time generic PCI code
192  * wants to generate a new address. The process of looking for
193  * an available address, each candidate is first "aligned" and
194  * then checked if the resource is available until a match is found.
195  *
196  * Since we are just checking candidates, don't use any fields other
197  * than res->start.
198  */
199 resource_size_t pcibios_align_resource(void *data, const struct resource *res,
200 				       const struct resource *empty_res,
201 				       resource_size_t size,
202 				       resource_size_t alignment)
203 {
204 	struct pci_dev *dev = data;
205 	resource_size_t align, start = res->start;
206 
207 	DBG_RES("pcibios_align_resource(%s, (%p) [%lx,%lx]/%x, 0x%lx, 0x%lx)\n",
208 		pci_name(((struct pci_dev *) data)),
209 		res->parent, res->start, res->end,
210 		(int) res->flags, size, alignment);
211 
212 	/* If it's not IO, then it's gotta be MEM */
213 	align = (res->flags & IORESOURCE_IO) ? PCIBIOS_MIN_IO : PCIBIOS_MIN_MEM;
214 	if (align > alignment)
215 		start = ALIGN(start, align);
216 	else
217 		start = pci_align_resource(dev, res, empty_res, size, alignment);
218 
219 	return start;
220 }
221 
222 /*
223  * A driver is enabling the device.  We make sure that all the appropriate
224  * bits are set to allow the device to operate as the driver is expecting.
225  * We enable the port IO and memory IO bits if the device has any BARs of
226  * that type, and we enable the PERR and SERR bits unconditionally.
227  * Drivers that do not need parity (eg graphics and possibly networking)
228  * can clear these bits if they want.
229  */
230 int pcibios_enable_device(struct pci_dev *dev, int mask)
231 {
232 	int err;
233 	u16 cmd, old_cmd;
234 
235 	err = pci_enable_resources(dev, mask);
236 	if (err < 0)
237 		return err;
238 
239 	pci_read_config_word(dev, PCI_COMMAND, &cmd);
240 	old_cmd = cmd;
241 
242 	cmd |= (PCI_COMMAND_SERR | PCI_COMMAND_PARITY);
243 
244 #if 0
245 	/* If bridge/bus controller has FBB enabled, child must too. */
246 	if (dev->bus->bridge_ctl & PCI_BRIDGE_CTL_FAST_BACK)
247 		cmd |= PCI_COMMAND_FAST_BACK;
248 #endif
249 
250 	if (cmd != old_cmd) {
251 		dev_info(&dev->dev, "enabling SERR and PARITY (%04x -> %04x)\n",
252 			old_cmd, cmd);
253 		pci_write_config_word(dev, PCI_COMMAND, cmd);
254 	}
255 	return 0;
256 }
257 
258 
259 /* PA-RISC specific */
260 void pcibios_register_hba(struct pci_hba_data *hba)
261 {
262 	if (pci_hba_count >= PCI_HBA_MAX) {
263 		printk(KERN_ERR "PCI: Too many Host Bus Adapters\n");
264 		return;
265 	}
266 
267 	parisc_pci_hba[pci_hba_count] = hba;
268 	hba->hba_num = pci_hba_count++;
269 }
270 
271 subsys_initcall(pcibios_init);
272