aboutsummaryrefslogtreecommitdiffstats
path: root/arch/mips/pci/ops-sni.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/mips/pci/ops-sni.c')
-rw-r--r--arch/mips/pci/ops-sni.c89
1 files changed, 89 insertions, 0 deletions
diff --git a/arch/mips/pci/ops-sni.c b/arch/mips/pci/ops-sni.c
new file mode 100644
index 000000000000..62bdd19c7f8e
--- /dev/null
+++ b/arch/mips/pci/ops-sni.c
@@ -0,0 +1,89 @@
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 * SNI specific PCI support for RM200/RM300.
7 *
8 * Copyright (C) 1997 - 2000, 2003 Ralf Baechle <ralf@linux-mips.org>
9 */
10#include <linux/kernel.h>
11#include <linux/pci.h>
12#include <linux/types.h>
13#include <asm/sni.h>
14
15/*
16 * It seems that on the RM200 only lower 3 bits of the 5 bit PCI device
17 * address are decoded. We therefore manually have to reject attempts at
18 * reading outside this range. Being on the paranoid side we only do this
19 * test for bus 0 and hope forwarding and decoding work properly for any
20 * subordinated busses.
21 *
22 * ASIC PCI only supports type 1 config cycles.
23 */
24static int set_config_address(unsigned int busno, unsigned int devfn, int reg)
25{
26 if ((devfn > 255) || (reg > 255))
27 return PCIBIOS_BAD_REGISTER_NUMBER;
28
29 if (busno == 0 && devfn >= PCI_DEVFN(8, 0))
30 return PCIBIOS_DEVICE_NOT_FOUND;
31
32 *(volatile u32 *)PCIMT_CONFIG_ADDRESS =
33 ((busno & 0xff) << 16) |
34 ((devfn & 0xff) << 8) |
35 (reg & 0xfc);
36
37 return PCIBIOS_SUCCESSFUL;
38}
39
40static int pcimt_read(struct pci_bus *bus, unsigned int devfn, int reg,
41 int size, u32 * val)
42{
43 int res;
44
45 if ((res = set_config_address(bus->number, devfn, reg)))
46 return res;
47
48 switch (size) {
49 case 1:
50 *val = *(volatile u8 *) (PCIMT_CONFIG_DATA + (reg & 3));
51 break;
52 case 2:
53 *val = *(volatile u16 *) (PCIMT_CONFIG_DATA + (reg & 2));
54 break;
55 case 4:
56 *val = *(volatile u32 *) PCIMT_CONFIG_DATA;
57 break;
58 }
59
60 return 0;
61}
62
63static int pcimt_write(struct pci_bus *bus, unsigned int devfn, int reg,
64 int size, u32 val)
65{
66 int res;
67
68 if ((res = set_config_address(bus->number, devfn, reg)))
69 return res;
70
71 switch (size) {
72 case 1:
73 *(volatile u8 *) (PCIMT_CONFIG_DATA + (reg & 3)) = val;
74 break;
75 case 2:
76 *(volatile u16 *) (PCIMT_CONFIG_DATA + (reg & 2)) = val;
77 break;
78 case 4:
79 *(volatile u32 *) PCIMT_CONFIG_DATA = val;
80 break;
81 }
82
83 return 0;
84}
85
86struct pci_ops sni_pci_ops = {
87 .read = pcimt_read,
88 .write = pcimt_write,
89};