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 #include <irq.h>
18 
19 /*
20  * PCIMT Shortcuts ...
21  */
22 #define SCSI	PCIMT_IRQ_SCSI
23 #define ETH	PCIMT_IRQ_ETHERNET
24 #define INTA	PCIMT_IRQ_INTA
25 #define INTB	PCIMT_IRQ_INTB
26 #define INTC	PCIMT_IRQ_INTC
27 #define INTD	PCIMT_IRQ_INTD
28 
29 /*
30  * Device 0: PCI EISA Bridge	(directly routed)
31  * Device 1: NCR53c810 SCSI	(directly routed)
32  * Device 2: PCnet32 Ethernet	(directly routed)
33  * Device 3: VGA		(routed to INTB)
34  * Device 4: Unused
35  * Device 5: Slot 2
36  * Device 6: Slot 3
37  * Device 7: Slot 4
38  *
39  * Documentation says the VGA is device 5 and device 3 is unused but that
40  * seem to be a documentation error.  At least on my RM200C the Cirrus
41  * Logic CL-GD5434 VGA is device 3.
42  */
43 static char irq_tab_rm200[8][5] = {
44 	/*	 INTA  INTB  INTC  INTD */
45 	{     0,    0,	  0,	0,    0 },	/* EISA bridge */
46 	{  SCSI, SCSI, SCSI, SCSI, SCSI },	/* SCSI */
47 	{   ETH,  ETH,	ETH,  ETH,  ETH },	/* Ethernet */
48 	{  INTB, INTB, INTB, INTB, INTB },	/* VGA */
49 	{     0,    0,	  0,	0,    0 },	/* Unused */
50 	{     0, INTB, INTC, INTD, INTA },	/* Slot 2 */
51 	{     0, INTC, INTD, INTA, INTB },	/* Slot 3 */
52 	{     0, INTD, INTA, INTB, INTC },	/* Slot 4 */
53 };
54 
55 /*
56  * In Revision D of the RM300 Device 2 has become a normal purpose Slot 1
57  *
58  * The VGA card is optional for RM300 systems.
59  */
60 static char irq_tab_rm300d[8][5] = {
61 	/*	 INTA  INTB  INTC  INTD */
62 	{     0,    0,	  0,	0,    0 },	/* EISA bridge */
63 	{  SCSI, SCSI, SCSI, SCSI, SCSI },	/* SCSI */
64 	{     0, INTC, INTD, INTA, INTB },	/* Slot 1 */
65 	{  INTB, INTB, INTB, INTB, INTB },	/* VGA */
66 	{     0,    0,	  0,	0,    0 },	/* Unused */
67 	{     0, INTB, INTC, INTD, INTA },	/* Slot 2 */
68 	{     0, INTC, INTD, INTA, INTB },	/* Slot 3 */
69 	{     0, INTD, INTA, INTB, INTC },	/* Slot 4 */
70 };
71 
72 static char irq_tab_rm300e[5][5] = {
73 	/*	 INTA  INTB  INTC  INTD */
74 	{     0,    0,	  0,	0,    0 },	/* HOST bridge */
75 	{  SCSI, SCSI, SCSI, SCSI, SCSI },	/* SCSI */
76 	{     0, INTC, INTD, INTA, INTB },	/* Bridge/i960 */
77 	{     0, INTD, INTA, INTB, INTC },	/* Slot 1 */
78 	{     0, INTA, INTB, INTC, INTD },	/* Slot 2 */
79 };
80 #undef SCSI
81 #undef ETH
82 #undef INTA
83 #undef INTB
84 #undef INTC
85 #undef INTD
86 
87 
88 /*
89  * PCIT Shortcuts ...
90  */
91 #define SCSI0	PCIT_IRQ_SCSI0
92 #define SCSI1	PCIT_IRQ_SCSI1
93 #define ETH	PCIT_IRQ_ETHERNET
94 #define INTA	PCIT_IRQ_INTA
95 #define INTB	PCIT_IRQ_INTB
96 #define INTC	PCIT_IRQ_INTC
97 #define INTD	PCIT_IRQ_INTD
98 
99 static char irq_tab_pcit[13][5] = {
100 	/*	 INTA  INTB  INTC  INTD */
101 	{     0,     0,	    0,	   0,	  0 },	/* HOST bridge */
102 	{ SCSI0, SCSI0, SCSI0, SCSI0, SCSI0 },	/* SCSI */
103 	{ SCSI1, SCSI1, SCSI1, SCSI1, SCSI1 },	/* SCSI */
104 	{   ETH,   ETH,	  ETH,	 ETH,	ETH },	/* Ethernet */
105 	{     0,  INTA,	 INTB,	INTC,  INTD },	/* PCI-PCI bridge */
106 	{     0,     0,	    0,	   0,	  0 },	/* Unused */
107 	{     0,     0,	    0,	   0,	  0 },	/* Unused */
108 	{     0,     0,	    0,	   0,	  0 },	/* Unused */
109 	{     0,  INTA,	 INTB,	INTC,  INTD },	/* Slot 1 */
110 	{     0,  INTB,	 INTC,	INTD,  INTA },	/* Slot 2 */
111 	{     0,  INTC,	 INTD,	INTA,  INTB },	/* Slot 3 */
112 	{     0,  INTD,	 INTA,	INTB,  INTC },	/* Slot 4 */
113 	{     0,  INTA,	 INTB,	INTC,  INTD },	/* Slot 5 */
114 };
115 
116 static char irq_tab_pcit_cplus[13][5] = {
117 	/*	 INTA  INTB  INTC  INTD */
118 	{     0,     0,	    0,	   0,	  0 },	/* HOST bridge */
119 	{     0,  INTB,	 INTC,	INTD,  INTA },	/* PCI Slot 9 */
120 	{     0,     0,	    0,	   0,	  0 },	/* PCI-EISA */
121 	{     0,     0,	    0,	   0,	  0 },	/* Unused */
122 	{     0,  INTA,	 INTB,	INTC,  INTD },	/* PCI-PCI bridge */
123 	{     0,  INTB,	 INTC,	INTD,  INTA },	/* fixup */
124 };
125 
is_rm300_revd(void)126 static inline int is_rm300_revd(void)
127 {
128 	unsigned char csmsr = *(volatile unsigned char *)PCIMT_CSMSR;
129 
130 	return (csmsr & 0xa0) == 0x20;
131 }
132 
pcibios_map_irq(const struct pci_dev * dev,u8 slot,u8 pin)133 int pcibios_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
134 {
135 	switch (sni_brd_type) {
136 	case SNI_BRD_PCI_TOWER_CPLUS:
137 		if (slot == 4) {
138 			/*
139 			 * SNI messed up interrupt wiring for onboard
140 			 * PCI bus 1; we need to fix this up here
141 			 */
142 			while (dev && dev->bus->number != 1)
143 				dev = dev->bus->self;
144 			if (dev && dev->devfn >= PCI_DEVFN(4, 0))
145 				slot = 5;
146 		}
147 		return irq_tab_pcit_cplus[slot][pin];
148 	case SNI_BRD_PCI_TOWER:
149 		return irq_tab_pcit[slot][pin];
150 
151 	case SNI_BRD_PCI_MTOWER:
152 		if (is_rm300_revd())
153 			return irq_tab_rm300d[slot][pin];
154 		fallthrough;
155 	case SNI_BRD_PCI_DESKTOP:
156 		return irq_tab_rm200[slot][pin];
157 
158 	case SNI_BRD_PCI_MTOWER_CPLUS:
159 		return irq_tab_rm300e[slot][pin];
160 	}
161 
162 	return 0;
163 }
164 
165 /* Do platform specific device initialization at pci_enable_device() time */
pcibios_plat_dev_init(struct pci_dev * dev)166 int pcibios_plat_dev_init(struct pci_dev *dev)
167 {
168 	return 0;
169 }
170