xref: /openbmc/linux/arch/alpha/kernel/sys_miata.c (revision c6fddb28)
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 	if (request_irq(16 + 2, no_action, 0, "halt-switch", NULL))
85 		pr_err("Failed to register halt-switch interrupt\n");
86 	if (request_irq(16 + 6, no_action, 0, "timer-cascade", NULL))
87 		pr_err("Failed to register timer-cascade interrupt\n");
88 }
89 
90 
91 /*
92  * PCI Fixup configuration.
93  *
94  * Summary @ PYXIS_INT_REQ:
95  * Bit      Meaning
96  * 0        Fan Fault
97  * 1        NMI
98  * 2        Halt/Reset switch
99  * 3        none
100  * 4        CID0 (Riser ID)
101  * 5        CID1 (Riser ID)
102  * 6        Interval timer
103  * 7        PCI-ISA Bridge
104  * 8        Ethernet
105  * 9        EIDE (deprecated, ISA 14/15 used)
106  *10        none
107  *11        USB
108  *12        Interrupt Line A from slot 4
109  *13        Interrupt Line B from slot 4
110  *14        Interrupt Line C from slot 4
111  *15        Interrupt Line D from slot 4
112  *16        Interrupt Line A from slot 5
113  *17        Interrupt line B from slot 5
114  *18        Interrupt Line C from slot 5
115  *19        Interrupt Line D from slot 5
116  *20        Interrupt Line A from slot 1
117  *21        Interrupt Line B from slot 1
118  *22        Interrupt Line C from slot 1
119  *23        Interrupt Line D from slot 1
120  *24        Interrupt Line A from slot 2
121  *25        Interrupt Line B from slot 2
122  *26        Interrupt Line C from slot 2
123  *27        Interrupt Line D from slot 2
124  *27        Interrupt Line A from slot 3
125  *29        Interrupt Line B from slot 3
126  *30        Interrupt Line C from slot 3
127  *31        Interrupt Line D from slot 3
128  *
129  * The device to slot mapping looks like:
130  *
131  * Slot     Device
132  *  3       DC21142 Ethernet
133  *  4       EIDE CMD646
134  *  5       none
135  *  6       USB
136  *  7       PCI-ISA bridge
137  *  8       PCI-PCI Bridge      (SBU Riser)
138  *  9       none
139  * 10       none
140  * 11       PCI on board slot 4 (SBU Riser)
141  * 12       PCI on board slot 5 (SBU Riser)
142  *
143  *  These are behind the bridge, so I'm not sure what to do...
144  *
145  * 13       PCI on board slot 1 (SBU Riser)
146  * 14       PCI on board slot 2 (SBU Riser)
147  * 15       PCI on board slot 3 (SBU Riser)
148  *
149  *
150  * This two layered interrupt approach means that we allocate IRQ 16 and
151  * above for PCI interrupts.  The IRQ relates to which bit the interrupt
152  * comes in on.  This makes interrupt processing much easier.
153  */
154 
155 static int
156 miata_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
157 {
158         static char irq_tab[18][5] = {
159 		/*INT    INTA   INTB   INTC   INTD */
160 		{16+ 8, 16+ 8, 16+ 8, 16+ 8, 16+ 8},  /* IdSel 14,  DC21142 */
161 		{   -1,    -1,    -1,    -1,    -1},  /* IdSel 15,  EIDE    */
162 		{   -1,    -1,    -1,    -1,    -1},  /* IdSel 16,  none    */
163 		{   -1,    -1,    -1,    -1,    -1},  /* IdSel 17,  none    */
164 		{   -1,    -1,    -1,    -1,    -1},  /* IdSel 18,  PCI-ISA */
165 		{   -1,    -1,    -1,    -1,    -1},  /* IdSel 19,  PCI-PCI */
166 		{   -1,    -1,    -1,    -1,    -1},  /* IdSel 20,  none    */
167 		{   -1,    -1,    -1,    -1,    -1},  /* IdSel 21,  none    */
168 		{16+12, 16+12, 16+13, 16+14, 16+15},  /* IdSel 22,  slot 4  */
169 		{16+16, 16+16, 16+17, 16+18, 16+19},  /* IdSel 23,  slot 5  */
170 		/* the next 7 are actually on PCI bus 1, across the bridge */
171 		{16+11, 16+11, 16+11, 16+11, 16+11},  /* IdSel 24,  QLISP/GL*/
172 		{   -1,    -1,    -1,    -1,    -1},  /* IdSel 25,  none    */
173 		{   -1,    -1,    -1,    -1,    -1},  /* IdSel 26,  none    */
174 		{   -1,    -1,    -1,    -1,    -1},  /* IdSel 27,  none    */
175 		{16+20, 16+20, 16+21, 16+22, 16+23},  /* IdSel 28,  slot 1  */
176 		{16+24, 16+24, 16+25, 16+26, 16+27},  /* IdSel 29,  slot 2  */
177 		{16+28, 16+28, 16+29, 16+30, 16+31},  /* IdSel 30,  slot 3  */
178 		/* This bridge is on the main bus of the later orig MIATA */
179 		{   -1,    -1,    -1,    -1,    -1},  /* IdSel 31,  PCI-PCI */
180         };
181 	const long min_idsel = 3, max_idsel = 20, irqs_per_slot = 5;
182 
183 	/* the USB function of the 82c693 has it's interrupt connected to
184            the 2nd 8259 controller. So we have to check for it first. */
185 
186 	if((slot == 7) && (PCI_FUNC(dev->devfn) == 3)) {
187 		u8 irq=0;
188 		struct pci_dev *pdev = pci_get_slot(dev->bus, dev->devfn & ~7);
189 		if(pdev == NULL || pci_read_config_byte(pdev, 0x40,&irq) != PCIBIOS_SUCCESSFUL) {
190 			pci_dev_put(pdev);
191 			return -1;
192 		}
193 		else	{
194 			pci_dev_put(pdev);
195 			return irq;
196 		}
197 	}
198 
199 	return COMMON_TABLE_LOOKUP;
200 }
201 
202 static u8
203 miata_swizzle(struct pci_dev *dev, u8 *pinp)
204 {
205 	int slot, pin = *pinp;
206 
207 	if (dev->bus->number == 0) {
208 		slot = PCI_SLOT(dev->devfn);
209 	}
210 	/* Check for the built-in bridge.  */
211 	else if ((PCI_SLOT(dev->bus->self->devfn) == 8) ||
212 		 (PCI_SLOT(dev->bus->self->devfn) == 20)) {
213 		slot = PCI_SLOT(dev->devfn) + 9;
214 	}
215 	else
216 	{
217 		/* Must be a card-based bridge.  */
218 		do {
219 			if ((PCI_SLOT(dev->bus->self->devfn) == 8) ||
220 			    (PCI_SLOT(dev->bus->self->devfn) == 20)) {
221 				slot = PCI_SLOT(dev->devfn) + 9;
222 				break;
223 			}
224 			pin = pci_swizzle_interrupt_pin(dev, pin);
225 
226 			/* Move up the chain of bridges.  */
227 			dev = dev->bus->self;
228 			/* Slot of the next bridge.  */
229 			slot = PCI_SLOT(dev->devfn);
230 		} while (dev->bus->self);
231 	}
232 	*pinp = pin;
233 	return slot;
234 }
235 
236 static void __init
237 miata_init_pci(void)
238 {
239 	cia_init_pci();
240 	SMC669_Init(0); /* it might be a GL (fails harmlessly if not) */
241 	es1888_init();
242 }
243 
244 static void
245 miata_kill_arch(int mode)
246 {
247 	cia_kill_arch(mode);
248 
249 #ifndef ALPHA_RESTORE_SRM_SETUP
250 	switch(mode) {
251 	case LINUX_REBOOT_CMD_RESTART:
252 		/* Who said DEC engineers have no sense of humor? ;-)  */
253 		if (alpha_using_srm) {
254 			*(vuip) PYXIS_RESET = 0x0000dead;
255 			mb();
256 		}
257 		break;
258 	case LINUX_REBOOT_CMD_HALT:
259 		break;
260 	case LINUX_REBOOT_CMD_POWER_OFF:
261 		break;
262 	}
263 
264 	halt();
265 #endif
266 }
267 
268 
269 /*
270  * The System Vector
271  */
272 
273 struct alpha_machine_vector miata_mv __initmv = {
274 	.vector_name		= "Miata",
275 	DO_EV5_MMU,
276 	DO_DEFAULT_RTC,
277 	DO_PYXIS_IO,
278 	.machine_check		= cia_machine_check,
279 	.max_isa_dma_address	= ALPHA_MAX_ISA_DMA_ADDRESS,
280 	.min_io_address		= DEFAULT_IO_BASE,
281 	.min_mem_address	= DEFAULT_MEM_BASE,
282 	.pci_dac_offset		= PYXIS_DAC_OFFSET,
283 
284 	.nr_irqs		= 48,
285 	.device_interrupt	= pyxis_device_interrupt,
286 
287 	.init_arch		= pyxis_init_arch,
288 	.init_irq		= miata_init_irq,
289 	.init_rtc		= common_init_rtc,
290 	.init_pci		= miata_init_pci,
291 	.kill_arch		= miata_kill_arch,
292 	.pci_map_irq		= miata_map_irq,
293 	.pci_swizzle		= miata_swizzle,
294 };
295 ALIAS_MV(miata)
296