xref: /openbmc/linux/arch/mips/pci/fixup-sni.c (revision 87c2ce3b)
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, 04 Ralf Baechle (ralf@linux-mips.org)
9  */
10 #include <linux/kernel.h>
11 #include <linux/init.h>
12 #include <linux/pci.h>
13 
14 #include <asm/mipsregs.h>
15 #include <asm/sni.h>
16 
17 /*
18  * Shortcuts ...
19  */
20 #define SCSI	PCIMT_IRQ_SCSI
21 #define ETH	PCIMT_IRQ_ETHERNET
22 #define INTA	PCIMT_IRQ_INTA
23 #define INTB	PCIMT_IRQ_INTB
24 #define INTC	PCIMT_IRQ_INTC
25 #define INTD	PCIMT_IRQ_INTD
26 
27 /*
28  * Device 0: PCI EISA Bridge	(directly routed)
29  * Device 1: NCR53c810 SCSI	(directly routed)
30  * Device 2: PCnet32 Ethernet	(directly routed)
31  * Device 3: VGA		(routed to INTB)
32  * Device 4: Unused
33  * Device 5: Slot 2
34  * Device 6: Slot 3
35  * Device 7: Slot 4
36  *
37  * Documentation says the VGA is device 5 and device 3 is unused but that
38  * seem to be a documentation error.  At least on my RM200C the Cirrus
39  * Logic CL-GD5434 VGA is device 3.
40  */
41 static char irq_tab_rm200[8][5] __initdata = {
42 	/*       INTA  INTB  INTC  INTD */
43 	{     0,    0,    0,    0,    0 },	/* EISA bridge */
44 	{  SCSI, SCSI, SCSI, SCSI, SCSI },	/* SCSI */
45 	{   ETH,  ETH,  ETH,  ETH,  ETH },	/* Ethernet */
46 	{  INTB, INTB, INTB, INTB, INTB },	/* VGA */
47 	{     0,    0,    0,    0,    0 },	/* Unused */
48 	{     0, INTB, INTC, INTD, INTA },	/* Slot 2 */
49 	{     0, INTC, INTD, INTA, INTB },	/* Slot 3 */
50 	{     0, INTD, INTA, INTB, INTC },	/* Slot 4 */
51 };
52 
53 /*
54  * In Revision D of the RM300 Device 2 has become a normal purpose Slot 1
55  *
56  * The VGA card is optional for RM300 systems.
57  */
58 static char irq_tab_rm300d[8][5] __initdata = {
59 	/*       INTA  INTB  INTC  INTD */
60 	{     0,    0,    0,    0,    0 },	/* EISA bridge */
61 	{  SCSI, SCSI, SCSI, SCSI, SCSI },	/* SCSI */
62 	{     0, INTC, INTD, INTA, INTB },	/* Slot 1 */
63 	{  INTB, INTB, INTB, INTB, INTB },	/* VGA */
64 	{     0,    0,    0,    0,    0 },	/* Unused */
65 	{     0, INTB, INTC, INTD, INTA },	/* Slot 2 */
66 	{     0, INTC, INTD, INTA, INTB },	/* Slot 3 */
67 	{     0, INTD, INTA, INTB, INTC },	/* Slot 4 */
68 };
69 
70 static inline int is_rm300_revd(void)
71 {
72 	unsigned char csmsr = *(volatile unsigned char *)PCIMT_CSMSR;
73 
74 	return (csmsr & 0xa0) == 0x20;
75 }
76 
77 int __init pcibios_map_irq(struct pci_dev *dev, u8 slot, u8 pin)
78 {
79 	if (is_rm300_revd())
80 		return irq_tab_rm300d[slot][pin];
81 
82 	return irq_tab_rm200[slot][pin];
83 }
84 
85 /* Do platform specific device initialization at pci_enable_device() time */
86 int pcibios_plat_dev_init(struct pci_dev *dev)
87 {
88 	return 0;
89 }
90