xref: /openbmc/linux/arch/mips/pci/ops-mace.c (revision 12eb4683)
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) 2000, 2001 Keith M Wesolowski
7  */
8 #include <linux/kernel.h>
9 #include <linux/init.h>
10 #include <linux/pci.h>
11 #include <linux/types.h>
12 #include <asm/pci.h>
13 #include <asm/ip32/mace.h>
14 
15 #if 0
16 # define DPRINTK(args...) printk(args);
17 #else
18 # define DPRINTK(args...)
19 #endif
20 
21 /*
22  * O2 has up to 5 PCI devices connected into the MACE bridge.  The device
23  * map looks like this:
24  *
25  * 0  aic7xxx 0
26  * 1  aic7xxx 1
27  * 2  expansion slot
28  * 3  N/C
29  * 4  N/C
30  */
31 
32 static inline int mkaddr(struct pci_bus *bus, unsigned int devfn,
33 	unsigned int reg)
34 {
35 	return ((bus->number & 0xff) << 16) |
36 		((devfn & 0xff) << 8) |
37 		(reg & 0xfc);
38 }
39 
40 
41 static int
42 mace_pci_read_config(struct pci_bus *bus, unsigned int devfn,
43 		     int reg, int size, u32 *val)
44 {
45 	u32 control = mace->pci.control;
46 
47 	/* disable master aborts interrupts during config read */
48 	mace->pci.control = control & ~MACEPCI_CONTROL_MAR_INT;
49 	mace->pci.config_addr = mkaddr(bus, devfn, reg);
50 	switch (size) {
51 	case 1:
52 		*val = mace->pci.config_data.b[(reg & 3) ^ 3];
53 		break;
54 	case 2:
55 		*val = mace->pci.config_data.w[((reg >> 1) & 1) ^ 1];
56 		break;
57 	case 4:
58 		*val = mace->pci.config_data.l;
59 		break;
60 	}
61 	/* ack possible master abort */
62 	mace->pci.error &= ~MACEPCI_ERROR_MASTER_ABORT;
63 	mace->pci.control = control;
64 	/*
65 	 * someone forgot to set the ultra bit for the onboard
66 	 * scsi chips; we fake it here
67 	 */
68 	if (bus->number == 0 && reg == 0x40 && size == 4 &&
69 	    (devfn == (1 << 3) || devfn == (2 << 3)))
70 		*val |= 0x1000;
71 
72 	DPRINTK("read%d: reg=%08x,val=%02x\n", size * 8, reg, *val);
73 
74 	return PCIBIOS_SUCCESSFUL;
75 }
76 
77 static int
78 mace_pci_write_config(struct pci_bus *bus, unsigned int devfn,
79 		      int reg, int size, u32 val)
80 {
81 	mace->pci.config_addr = mkaddr(bus, devfn, reg);
82 	switch (size) {
83 	case 1:
84 		mace->pci.config_data.b[(reg & 3) ^ 3] = val;
85 		break;
86 	case 2:
87 		mace->pci.config_data.w[((reg >> 1) & 1) ^ 1] = val;
88 		break;
89 	case 4:
90 		mace->pci.config_data.l = val;
91 		break;
92 	}
93 
94 	DPRINTK("write%d: reg=%08x,val=%02x\n", size * 8, reg, val);
95 
96 	return PCIBIOS_SUCCESSFUL;
97 }
98 
99 struct pci_ops mace_pci_ops = {
100 	.read = mace_pci_read_config,
101 	.write = mace_pci_write_config,
102 };
103