xref: /openbmc/linux/arch/alpha/kernel/sys_miata.c (revision ead75150)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *	linux/arch/alpha/kernel/sys_miata.c
4  *
5  *	Copyright (C) 1995 David A Rusling
6  *	Copyright (C) 1996 Jay A Estabrook
7  *	Copyright (C) 1998, 1999, 2000 Richard Henderson
8  *
9  * Code supporting the MIATA (EV56+PYXIS).
10  */
11 
12 #include <linux/kernel.h>
13 #include <linux/types.h>
14 #include <linux/mm.h>
15 #include <linux/sched.h>
16 #include <linux/pci.h>
17 #include <linux/init.h>
18 #include <linux/reboot.h>
19 
20 #include <asm/ptrace.h>
21 #include <asm/dma.h>
22 #include <asm/irq.h>
23 #include <asm/mmu_context.h>
24 #include <asm/io.h>
25 #include <asm/pgtable.h>
26 #include <asm/core_cia.h>
27 #include <asm/tlbflush.h>
28 
29 #include "proto.h"
30 #include "irq_impl.h"
31 #include "pci_impl.h"
32 #include "machvec_impl.h"
33 
34 
35 static void
36 miata_srm_device_interrupt(unsigned long vector)
37 {
38 	int irq;
39 
40 	irq = (vector - 0x800) >> 4;
41 
42 	/*
43 	 * I really hate to do this, but the MIATA SRM console ignores the
44 	 *  low 8 bits in the interrupt summary register, and reports the
45 	 *  vector 0x80 *lower* than I expected from the bit numbering in
46 	 *  the documentation.
47 	 * This was done because the low 8 summary bits really aren't used
48 	 *  for reporting any interrupts (the PCI-ISA bridge, bit 7, isn't
49 	 *  used for this purpose, as PIC interrupts are delivered as the
50 	 *  vectors 0x800-0x8f0).
51 	 * But I really don't want to change the fixup code for allocation
52 	 *  of IRQs, nor the alpha_irq_mask maintenance stuff, both of which
53 	 *  look nice and clean now.
54 	 * So, here's this grotty hack... :-(
55 	 */
56 	if (irq >= 16)
57 		irq = irq + 8;
58 
59 	handle_irq(irq);
60 }
61 
62 static void __init
63 miata_init_irq(void)
64 {
65 	if (alpha_using_srm)
66 		alpha_mv.device_interrupt = miata_srm_device_interrupt;
67 
68 #if 0
69 	/* These break on MiataGL so we'll try not to do it at all.  */
70 	*(vulp)PYXIS_INT_HILO = 0x000000B2UL; mb();	/* ISA/NMI HI */
71 	*(vulp)PYXIS_RT_COUNT = 0UL; mb();		/* clear count */
72 #endif
73 
74 	init_i8259a_irqs();
75 
76 	/* Not interested in the bogus interrupts (3,10), Fan Fault (0),
77            NMI (1), or EIDE (9).
78 
79 	   We also disable the risers (4,5), since we don't know how to
80 	   route the interrupts behind the bridge.  */
81 	init_pyxis_irqs(0x63b0000);
82 
83 	common_init_isa_dma();
84 	setup_irq(16+2, &halt_switch_irqaction);	/* SRM only? */
85 	setup_irq(16+6, &timer_cascade_irqaction);
86 }
87 
88 
89 /*
90  * PCI Fixup configuration.
91  *
92  * Summary @ PYXIS_INT_REQ:
93  * Bit      Meaning
94  * 0        Fan Fault
95  * 1        NMI
96  * 2        Halt/Reset switch
97  * 3        none
98  * 4        CID0 (Riser ID)
99  * 5        CID1 (Riser ID)
100  * 6        Interval timer
101  * 7        PCI-ISA Bridge
102  * 8        Ethernet
103  * 9        EIDE (deprecated, ISA 14/15 used)
104  *10        none
105  *11        USB
106  *12        Interrupt Line A from slot 4
107  *13        Interrupt Line B from slot 4
108  *14        Interrupt Line C from slot 4
109  *15        Interrupt Line D from slot 4
110  *16        Interrupt Line A from slot 5
111  *17        Interrupt line B from slot 5
112  *18        Interrupt Line C from slot 5
113  *19        Interrupt Line D from slot 5
114  *20        Interrupt Line A from slot 1
115  *21        Interrupt Line B from slot 1
116  *22        Interrupt Line C from slot 1
117  *23        Interrupt Line D from slot 1
118  *24        Interrupt Line A from slot 2
119  *25        Interrupt Line B from slot 2
120  *26        Interrupt Line C from slot 2
121  *27        Interrupt Line D from slot 2
122  *27        Interrupt Line A from slot 3
123  *29        Interrupt Line B from slot 3
124  *30        Interrupt Line C from slot 3
125  *31        Interrupt Line D from slot 3
126  *
127  * The device to slot mapping looks like:
128  *
129  * Slot     Device
130  *  3       DC21142 Ethernet
131  *  4       EIDE CMD646
132  *  5       none
133  *  6       USB
134  *  7       PCI-ISA bridge
135  *  8       PCI-PCI Bridge      (SBU Riser)
136  *  9       none
137  * 10       none
138  * 11       PCI on board slot 4 (SBU Riser)
139  * 12       PCI on board slot 5 (SBU Riser)
140  *
141  *  These are behind the bridge, so I'm not sure what to do...
142  *
143  * 13       PCI on board slot 1 (SBU Riser)
144  * 14       PCI on board slot 2 (SBU Riser)
145  * 15       PCI on board slot 3 (SBU Riser)
146  *
147  *
148  * This two layered interrupt approach means that we allocate IRQ 16 and
149  * above for PCI interrupts.  The IRQ relates to which bit the interrupt
150  * comes in on.  This makes interrupt processing much easier.
151  */
152 
153 static int
154 miata_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
155 {
156         static char irq_tab[18][5] = {
157 		/*INT    INTA   INTB   INTC   INTD */
158 		{16+ 8, 16+ 8, 16+ 8, 16+ 8, 16+ 8},  /* IdSel 14,  DC21142 */
159 		{   -1,    -1,    -1,    -1,    -1},  /* IdSel 15,  EIDE    */
160 		{   -1,    -1,    -1,    -1,    -1},  /* IdSel 16,  none    */
161 		{   -1,    -1,    -1,    -1,    -1},  /* IdSel 17,  none    */
162 		{   -1,    -1,    -1,    -1,    -1},  /* IdSel 18,  PCI-ISA */
163 		{   -1,    -1,    -1,    -1,    -1},  /* IdSel 19,  PCI-PCI */
164 		{   -1,    -1,    -1,    -1,    -1},  /* IdSel 20,  none    */
165 		{   -1,    -1,    -1,    -1,    -1},  /* IdSel 21,  none    */
166 		{16+12, 16+12, 16+13, 16+14, 16+15},  /* IdSel 22,  slot 4  */
167 		{16+16, 16+16, 16+17, 16+18, 16+19},  /* IdSel 23,  slot 5  */
168 		/* the next 7 are actually on PCI bus 1, across the bridge */
169 		{16+11, 16+11, 16+11, 16+11, 16+11},  /* IdSel 24,  QLISP/GL*/
170 		{   -1,    -1,    -1,    -1,    -1},  /* IdSel 25,  none    */
171 		{   -1,    -1,    -1,    -1,    -1},  /* IdSel 26,  none    */
172 		{   -1,    -1,    -1,    -1,    -1},  /* IdSel 27,  none    */
173 		{16+20, 16+20, 16+21, 16+22, 16+23},  /* IdSel 28,  slot 1  */
174 		{16+24, 16+24, 16+25, 16+26, 16+27},  /* IdSel 29,  slot 2  */
175 		{16+28, 16+28, 16+29, 16+30, 16+31},  /* IdSel 30,  slot 3  */
176 		/* This bridge is on the main bus of the later orig MIATA */
177 		{   -1,    -1,    -1,    -1,    -1},  /* IdSel 31,  PCI-PCI */
178         };
179 	const long min_idsel = 3, max_idsel = 20, irqs_per_slot = 5;
180 
181 	/* the USB function of the 82c693 has it's interrupt connected to
182            the 2nd 8259 controller. So we have to check for it first. */
183 
184 	if((slot == 7) && (PCI_FUNC(dev->devfn) == 3)) {
185 		u8 irq=0;
186 		struct pci_dev *pdev = pci_get_slot(dev->bus, dev->devfn & ~7);
187 		if(pdev == NULL || pci_read_config_byte(pdev, 0x40,&irq) != PCIBIOS_SUCCESSFUL) {
188 			pci_dev_put(pdev);
189 			return -1;
190 		}
191 		else	{
192 			pci_dev_put(pdev);
193 			return irq;
194 		}
195 	}
196 
197 	return COMMON_TABLE_LOOKUP;
198 }
199 
200 static u8
201 miata_swizzle(struct pci_dev *dev, u8 *pinp)
202 {
203 	int slot, pin = *pinp;
204 
205 	if (dev->bus->number == 0) {
206 		slot = PCI_SLOT(dev->devfn);
207 	}
208 	/* Check for the built-in bridge.  */
209 	else if ((PCI_SLOT(dev->bus->self->devfn) == 8) ||
210 		 (PCI_SLOT(dev->bus->self->devfn) == 20)) {
211 		slot = PCI_SLOT(dev->devfn) + 9;
212 	}
213 	else
214 	{
215 		/* Must be a card-based bridge.  */
216 		do {
217 			if ((PCI_SLOT(dev->bus->self->devfn) == 8) ||
218 			    (PCI_SLOT(dev->bus->self->devfn) == 20)) {
219 				slot = PCI_SLOT(dev->devfn) + 9;
220 				break;
221 			}
222 			pin = pci_swizzle_interrupt_pin(dev, pin);
223 
224 			/* Move up the chain of bridges.  */
225 			dev = dev->bus->self;
226 			/* Slot of the next bridge.  */
227 			slot = PCI_SLOT(dev->devfn);
228 		} while (dev->bus->self);
229 	}
230 	*pinp = pin;
231 	return slot;
232 }
233 
234 static void __init
235 miata_init_pci(void)
236 {
237 	cia_init_pci();
238 	SMC669_Init(0); /* it might be a GL (fails harmlessly if not) */
239 	es1888_init();
240 }
241 
242 static void
243 miata_kill_arch(int mode)
244 {
245 	cia_kill_arch(mode);
246 
247 #ifndef ALPHA_RESTORE_SRM_SETUP
248 	switch(mode) {
249 	case LINUX_REBOOT_CMD_RESTART:
250 		/* Who said DEC engineers have no sense of humor? ;-)  */
251 		if (alpha_using_srm) {
252 			*(vuip) PYXIS_RESET = 0x0000dead;
253 			mb();
254 		}
255 		break;
256 	case LINUX_REBOOT_CMD_HALT:
257 		break;
258 	case LINUX_REBOOT_CMD_POWER_OFF:
259 		break;
260 	}
261 
262 	halt();
263 #endif
264 }
265 
266 
267 /*
268  * The System Vector
269  */
270 
271 struct alpha_machine_vector miata_mv __initmv = {
272 	.vector_name		= "Miata",
273 	DO_EV5_MMU,
274 	DO_DEFAULT_RTC,
275 	DO_PYXIS_IO,
276 	.machine_check		= cia_machine_check,
277 	.max_isa_dma_address	= ALPHA_MAX_ISA_DMA_ADDRESS,
278 	.min_io_address		= DEFAULT_IO_BASE,
279 	.min_mem_address	= DEFAULT_MEM_BASE,
280 	.pci_dac_offset		= PYXIS_DAC_OFFSET,
281 
282 	.nr_irqs		= 48,
283 	.device_interrupt	= pyxis_device_interrupt,
284 
285 	.init_arch		= pyxis_init_arch,
286 	.init_irq		= miata_init_irq,
287 	.init_rtc		= common_init_rtc,
288 	.init_pci		= miata_init_pci,
289 	.kill_arch		= miata_kill_arch,
290 	.pci_map_irq		= miata_map_irq,
291 	.pci_swizzle		= miata_swizzle,
292 };
293 ALIAS_MV(miata)
294