aboutsummaryrefslogtreecommitdiffstats
path: root/arch/alpha/kernel/sys_rawhide.c
blob: f3aec7e085c8c6f0a0165a7f47af0fe076312377 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
/*
 *	linux/arch/alpha/kernel/sys_rawhide.c
 *
 *	Copyright (C) 1995 David A Rusling
 *	Copyright (C) 1996 Jay A Estabrook
 *	Copyright (C) 1998, 1999 Richard Henderson
 *
 * Code supporting the RAWHIDE.
 */

#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/mm.h>
#include <linux/sched.h>
#include <linux/pci.h>
#include <linux/init.h>

#include <asm/ptrace.h>
#include <asm/system.h>
#include <asm/dma.h>
#include <asm/irq.h>
#include <asm/mmu_context.h>
#include <asm/io.h>
#include <asm/pgtable.h>
#include <asm/core_mcpcia.h>
#include <asm/tlbflush.h>

#include "proto.h"
#include "irq_impl.h"
#include "pci_impl.h"
#include "machvec_impl.h"


/*
 * HACK ALERT! only the boot cpu is used for interrupts.
 */


/* Note mask bit is true for ENABLED irqs.  */

static unsigned int hose_irq_masks[4] = {
	0xff0000, 0xfe0000, 0xff0000, 0xff0000
};
static unsigned int cached_irq_masks[4];
DEFINE_SPINLOCK(rawhide_irq_lock);

static inline void
rawhide_update_irq_hw(int hose, int mask)
{
	*(vuip)MCPCIA_INT_MASK0(MCPCIA_HOSE2MID(hose)) = mask;
	mb();
	*(vuip)MCPCIA_INT_MASK0(MCPCIA_HOSE2MID(hose));
}

#define hose_exists(h) \
  (((h) < MCPCIA_MAX_HOSES) && (cached_irq_masks[(h)] != 0))

static inline void 
rawhide_enable_irq(unsigned int irq)
{
	unsigned int mask, hose;

	irq -= 16;
	hose = irq / 24;
	if (!hose_exists(hose)) /* if hose non-existent, exit */
		return;

	irq -= hose * 24;
	mask = 1 << irq;

	spin_lock(&rawhide_irq_lock);
	mask |= cached_irq_masks[hose];
	cached_irq_masks[hose] = mask;
	rawhide_update_irq_hw(hose, mask);
	spin_unlock(&rawhide_irq_lock);
}

static void 
rawhide_disable_irq(unsigned int irq)
{
	unsigned int mask, hose;

	irq -= 16;
	hose = irq / 24;
	if (!hose_exists(hose)) /* if hose non-existent, exit */
		return;

	irq -= hose * 24;
	mask = ~(1 << irq) | hose_irq_masks[hose];

	spin_lock(&rawhide_irq_lock);
	mask &= cached_irq_masks[hose];
	cached_irq_masks[hose] = mask;
	rawhide_update_irq_hw(hose, mask);
	spin_unlock(&rawhide_irq_lock);
}

static void
rawhide_mask_and_ack_irq(unsigned int irq)
{
	unsigned int mask, mask1, hose;

	irq -= 16;
	hose = irq / 24;
	if (!hose_exists(hose)) /* if hose non-existent, exit */
		return;

	irq -= hose * 24;
	mask1 = 1 << irq;
	mask = ~mask1 | hose_irq_masks[hose];

	spin_lock(&rawhide_irq_lock);

	mask &= cached_irq_masks[hose];
	cached_irq_masks[hose] = mask;
	rawhide_update_irq_hw(hose, mask);

	/* Clear the interrupt.  */
	*(vuip)MCPCIA_INT_REQ(MCPCIA_HOSE2MID(hose)) = mask1;

	spin_unlock(&rawhide_irq_lock);
}

static unsigned int
rawhide_startup_irq(unsigned int irq)
{
	rawhide_enable_irq(irq);
	return 0;
}

static void
rawhide_end_irq(unsigned int irq)
{
	if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
		rawhide_enable_irq(irq);
}

static struct irq_chip rawhide_irq_type = {
	.typename	= "RAWHIDE",
	.startup	= rawhide_startup_irq,
	.shutdown	= rawhide_disable_irq,
	.enable		= rawhide_enable_irq,
	.disable	= rawhide_disable_irq,
	.ack		= rawhide_mask_and_ack_irq,
	.end		= rawhide_end_irq,
};

static void 
rawhide_srm_device_interrupt(unsigned long vector)
{
	int irq;

	irq = (vector - 0x800) >> 4;

        /*
         * The RAWHIDE SRM console reports PCI interrupts with a vector
	 * 0x80 *higher* than one might expect, as PCI IRQ 0 (ie bit 0)
	 * shows up as IRQ 24, etc, etc. We adjust it down by 8 to have
	 * it line up with the actual bit numbers from the REQ registers,
	 * which is how we manage the interrupts/mask. Sigh...
	 *
	 * Also, PCI #1 interrupts are offset some more... :-(
         */

	if (irq == 52) {
		/* SCSI on PCI1 is special.  */
		irq = 72;
	}

	/* Adjust by which hose it is from.  */
	irq -= ((irq + 16) >> 2) & 0x38;

	handle_irq(irq);
}

static void __init
rawhide_init_irq(void)
{
	struct pci_controller *hose;
	long i;

	mcpcia_init_hoses();

	/* Clear them all; only hoses that exist will be non-zero. */
	for (i = 0; i < MCPCIA_MAX_HOSES; i++) cached_irq_masks[i] = 0;

	for (hose = hose_head; hose; hose = hose->next) {
		unsigned int h = hose->index;
		unsigned int mask = hose_irq_masks[h];

		cached_irq_masks[h] = mask;
		*(vuip)MCPCIA_INT_MASK0(MCPCIA_HOSE2MID(h)) = mask;
		*(vuip)MCPCIA_INT_MASK1(MCPCIA_HOSE2MID(h)) = 0;
	}

	for (i = 16; i < 128; ++i) {
		irq_desc[i].status = IRQ_DISABLED | IRQ_LEVEL;
		irq_desc[i].chip = &rawhide_irq_type;
	}

	init_i8259a_irqs();
	common_init_isa_dma();
}

/*
 * PCI Fixup configuration.
 *
 * Summary @ MCPCIA_PCI0_INT_REQ:
 * Bit      Meaning
 * 0        Interrupt Line A from slot 2 PCI0
 * 1        Interrupt Line B from slot 2 PCI0
 * 2        Interrupt Line C from slot 2 PCI0
 * 3        Interrupt Line D from slot 2 PCI0
 * 4        Interrupt Line A from slot 3 PCI0
 * 5        Interrupt Line B from slot 3 PCI0
 * 6        Interrupt Line C from slot 3 PCI0
 * 7        Interrupt Line D from slot 3 PCI0
 * 8        Interrupt Line A from slot 4 PCI0
 * 9        Interrupt Line B from slot 4 PCI0
 * 10       Interrupt Line C from slot 4 PCI0
 * 11       Interrupt Line D from slot 4 PCI0
 * 12       Interrupt Line A from slot 5 PCI0
 * 13       Interrupt Line B from slot 5 PCI0
 * 14       Interrupt Line C from slot 5 PCI0
 * 15       Interrupt Line D from slot 5 PCI0
 * 16       EISA interrupt (PCI 0) or SCSI interrupt (PCI 1)
 * 17-23    NA
 *
 * IdSel	
 *   1	 EISA bridge (PCI bus 0 only)
 *   2 	 PCI option slot 2
 *   3	 PCI option slot 3
 *   4   PCI option slot 4
 *   5   PCI option slot 5
 * 
 */

static int __init
rawhide_map_irq(struct pci_dev *dev, u8 slot, u8 pin)
{
	static char irq_tab[5][5] __initdata = {
		/*INT    INTA   INTB   INTC   INTD */
		{ 16+16, 16+16, 16+16, 16+16, 16+16}, /* IdSel 1 SCSI PCI 1 */
		{ 16+ 0, 16+ 0, 16+ 1, 16+ 2, 16+ 3}, /* IdSel 2 slot 2 */
		{ 16+ 4, 16+ 4, 16+ 5, 16+ 6, 16+ 7}, /* IdSel 3 slot 3 */
		{ 16+ 8, 16+ 8, 16+ 9, 16+10, 16+11}, /* IdSel 4 slot 4 */
		{ 16+12, 16+12, 16+13, 16+14, 16+15}  /* IdSel 5 slot 5 */
	};
	const long min_idsel = 1, max_idsel = 5, irqs_per_slot = 5;

	struct pci_controller *hose = dev->sysdata;
	int irq = COMMON_TABLE_LOOKUP;
	if (irq >= 0)
		irq += 24 * hose->index;
	return irq;
}


/*
 * The System Vector
 */

struct alpha_machine_vector rawhide_mv __initmv = {
	.vector_name		= "Rawhide",
	DO_EV5_MMU,
	DO_DEFAULT_RTC,
	DO_MCPCIA_IO,
	.machine_check		= mcpcia_machine_check,
	.max_isa_dma_address	= ALPHA_MAX_ISA_DMA_ADDRESS,
	.min_io_address		= DEFAULT_IO_BASE,
	.min_mem_address	= MCPCIA_DEFAULT_MEM_BASE,
	.pci_dac_offset		= MCPCIA_DAC_OFFSET,

	.nr_irqs		= 128,
	.device_interrupt	= rawhide_srm_device_interrupt,

	.init_arch		= mcpcia_init_arch,
	.init_irq		= rawhide_init_irq,
	.init_rtc		= common_init_rtc,
	.init_pci		= common_init_pci,
	.kill_arch		= NULL,
	.pci_map_irq		= rawhide_map_irq,
	.pci_swizzle		= common_swizzle,
};
ALIAS_MV(rawhide)