xref: /linux/arch/alpha/kernel/sys_rawhide.c (revision f3d9478b2ce468c3115b02ecae7e975990697f15)
1 /*
2  *	linux/arch/alpha/kernel/sys_rawhide.c
3  *
4  *	Copyright (C) 1995 David A Rusling
5  *	Copyright (C) 1996 Jay A Estabrook
6  *	Copyright (C) 1998, 1999 Richard Henderson
7  *
8  * Code supporting the RAWHIDE.
9  */
10 
11 #include <linux/kernel.h>
12 #include <linux/types.h>
13 #include <linux/mm.h>
14 #include <linux/sched.h>
15 #include <linux/pci.h>
16 #include <linux/init.h>
17 
18 #include <asm/ptrace.h>
19 #include <asm/system.h>
20 #include <asm/dma.h>
21 #include <asm/irq.h>
22 #include <asm/mmu_context.h>
23 #include <asm/io.h>
24 #include <asm/pgtable.h>
25 #include <asm/core_mcpcia.h>
26 #include <asm/tlbflush.h>
27 
28 #include "proto.h"
29 #include "irq_impl.h"
30 #include "pci_impl.h"
31 #include "machvec_impl.h"
32 
33 
34 /*
35  * HACK ALERT! only the boot cpu is used for interrupts.
36  */
37 
38 
39 /* Note mask bit is true for ENABLED irqs.  */
40 
41 static unsigned int hose_irq_masks[4] = {
42 	0xff0000, 0xfe0000, 0xff0000, 0xff0000
43 };
44 static unsigned int cached_irq_masks[4];
45 DEFINE_SPINLOCK(rawhide_irq_lock);
46 
47 static inline void
48 rawhide_update_irq_hw(int hose, int mask)
49 {
50 	*(vuip)MCPCIA_INT_MASK0(MCPCIA_HOSE2MID(hose)) = mask;
51 	mb();
52 	*(vuip)MCPCIA_INT_MASK0(MCPCIA_HOSE2MID(hose));
53 }
54 
55 static inline void
56 rawhide_enable_irq(unsigned int irq)
57 {
58 	unsigned int mask, hose;
59 
60 	irq -= 16;
61 	hose = irq / 24;
62 	irq -= hose * 24;
63 	mask = 1 << irq;
64 
65 	spin_lock(&rawhide_irq_lock);
66 	mask |= cached_irq_masks[hose];
67 	cached_irq_masks[hose] = mask;
68 	rawhide_update_irq_hw(hose, mask);
69 	spin_unlock(&rawhide_irq_lock);
70 }
71 
72 static void
73 rawhide_disable_irq(unsigned int irq)
74 {
75 	unsigned int mask, hose;
76 
77 	irq -= 16;
78 	hose = irq / 24;
79 	irq -= hose * 24;
80 	mask = ~(1 << irq) | hose_irq_masks[hose];
81 
82 	spin_lock(&rawhide_irq_lock);
83 	mask &= cached_irq_masks[hose];
84 	cached_irq_masks[hose] = mask;
85 	rawhide_update_irq_hw(hose, mask);
86 	spin_unlock(&rawhide_irq_lock);
87 }
88 
89 static void
90 rawhide_mask_and_ack_irq(unsigned int irq)
91 {
92 	unsigned int mask, mask1, hose;
93 
94 	irq -= 16;
95 	hose = irq / 24;
96 	irq -= hose * 24;
97 	mask1 = 1 << irq;
98 	mask = ~mask1 | hose_irq_masks[hose];
99 
100 	spin_lock(&rawhide_irq_lock);
101 
102 	mask &= cached_irq_masks[hose];
103 	cached_irq_masks[hose] = mask;
104 	rawhide_update_irq_hw(hose, mask);
105 
106 	/* Clear the interrupt.  */
107 	*(vuip)MCPCIA_INT_REQ(MCPCIA_HOSE2MID(hose)) = mask1;
108 
109 	spin_unlock(&rawhide_irq_lock);
110 }
111 
112 static unsigned int
113 rawhide_startup_irq(unsigned int irq)
114 {
115 	rawhide_enable_irq(irq);
116 	return 0;
117 }
118 
119 static void
120 rawhide_end_irq(unsigned int irq)
121 {
122 	if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
123 		rawhide_enable_irq(irq);
124 }
125 
126 static struct hw_interrupt_type rawhide_irq_type = {
127 	.typename	= "RAWHIDE",
128 	.startup	= rawhide_startup_irq,
129 	.shutdown	= rawhide_disable_irq,
130 	.enable		= rawhide_enable_irq,
131 	.disable	= rawhide_disable_irq,
132 	.ack		= rawhide_mask_and_ack_irq,
133 	.end		= rawhide_end_irq,
134 };
135 
136 static void
137 rawhide_srm_device_interrupt(unsigned long vector, struct pt_regs * regs)
138 {
139 	int irq;
140 
141 	irq = (vector - 0x800) >> 4;
142 
143         /*
144          * The RAWHIDE SRM console reports PCI interrupts with a vector
145 	 * 0x80 *higher* than one might expect, as PCI IRQ 0 (ie bit 0)
146 	 * shows up as IRQ 24, etc, etc. We adjust it down by 8 to have
147 	 * it line up with the actual bit numbers from the REQ registers,
148 	 * which is how we manage the interrupts/mask. Sigh...
149 	 *
150 	 * Also, PCI #1 interrupts are offset some more... :-(
151          */
152 
153 	if (irq == 52) {
154 		/* SCSI on PCI1 is special.  */
155 		irq = 72;
156 	}
157 
158 	/* Adjust by which hose it is from.  */
159 	irq -= ((irq + 16) >> 2) & 0x38;
160 
161 	handle_irq(irq, regs);
162 }
163 
164 static void __init
165 rawhide_init_irq(void)
166 {
167 	struct pci_controller *hose;
168 	long i;
169 
170 	mcpcia_init_hoses();
171 
172 	for (hose = hose_head; hose; hose = hose->next) {
173 		unsigned int h = hose->index;
174 		unsigned int mask = hose_irq_masks[h];
175 
176 		cached_irq_masks[h] = mask;
177 		*(vuip)MCPCIA_INT_MASK0(MCPCIA_HOSE2MID(h)) = mask;
178 		*(vuip)MCPCIA_INT_MASK1(MCPCIA_HOSE2MID(h)) = 0;
179 	}
180 
181 	for (i = 16; i < 128; ++i) {
182 		irq_desc[i].status = IRQ_DISABLED | IRQ_LEVEL;
183 		irq_desc[i].handler = &rawhide_irq_type;
184 	}
185 
186 	init_i8259a_irqs();
187 	common_init_isa_dma();
188 }
189 
190 /*
191  * PCI Fixup configuration.
192  *
193  * Summary @ MCPCIA_PCI0_INT_REQ:
194  * Bit      Meaning
195  * 0        Interrupt Line A from slot 2 PCI0
196  * 1        Interrupt Line B from slot 2 PCI0
197  * 2        Interrupt Line C from slot 2 PCI0
198  * 3        Interrupt Line D from slot 2 PCI0
199  * 4        Interrupt Line A from slot 3 PCI0
200  * 5        Interrupt Line B from slot 3 PCI0
201  * 6        Interrupt Line C from slot 3 PCI0
202  * 7        Interrupt Line D from slot 3 PCI0
203  * 8        Interrupt Line A from slot 4 PCI0
204  * 9        Interrupt Line B from slot 4 PCI0
205  * 10       Interrupt Line C from slot 4 PCI0
206  * 11       Interrupt Line D from slot 4 PCI0
207  * 12       Interrupt Line A from slot 5 PCI0
208  * 13       Interrupt Line B from slot 5 PCI0
209  * 14       Interrupt Line C from slot 5 PCI0
210  * 15       Interrupt Line D from slot 5 PCI0
211  * 16       EISA interrupt (PCI 0) or SCSI interrupt (PCI 1)
212  * 17-23    NA
213  *
214  * IdSel
215  *   1	 EISA bridge (PCI bus 0 only)
216  *   2 	 PCI option slot 2
217  *   3	 PCI option slot 3
218  *   4   PCI option slot 4
219  *   5   PCI option slot 5
220  *
221  */
222 
223 static int __init
224 rawhide_map_irq(struct pci_dev *dev, u8 slot, u8 pin)
225 {
226 	static char irq_tab[5][5] __initdata = {
227 		/*INT    INTA   INTB   INTC   INTD */
228 		{ 16+16, 16+16, 16+16, 16+16, 16+16}, /* IdSel 1 SCSI PCI 1 */
229 		{ 16+ 0, 16+ 0, 16+ 1, 16+ 2, 16+ 3}, /* IdSel 2 slot 2 */
230 		{ 16+ 4, 16+ 4, 16+ 5, 16+ 6, 16+ 7}, /* IdSel 3 slot 3 */
231 		{ 16+ 8, 16+ 8, 16+ 9, 16+10, 16+11}, /* IdSel 4 slot 4 */
232 		{ 16+12, 16+12, 16+13, 16+14, 16+15}  /* IdSel 5 slot 5 */
233 	};
234 	const long min_idsel = 1, max_idsel = 5, irqs_per_slot = 5;
235 
236 	struct pci_controller *hose = dev->sysdata;
237 	int irq = COMMON_TABLE_LOOKUP;
238 	if (irq >= 0)
239 		irq += 24 * hose->index;
240 	return irq;
241 }
242 
243 
244 /*
245  * The System Vector
246  */
247 
248 struct alpha_machine_vector rawhide_mv __initmv = {
249 	.vector_name		= "Rawhide",
250 	DO_EV5_MMU,
251 	DO_DEFAULT_RTC,
252 	DO_MCPCIA_IO,
253 	.machine_check		= mcpcia_machine_check,
254 	.max_isa_dma_address	= ALPHA_MAX_ISA_DMA_ADDRESS,
255 	.min_io_address		= DEFAULT_IO_BASE,
256 	.min_mem_address	= MCPCIA_DEFAULT_MEM_BASE,
257 	.pci_dac_offset		= MCPCIA_DAC_OFFSET,
258 
259 	.nr_irqs		= 128,
260 	.device_interrupt	= rawhide_srm_device_interrupt,
261 
262 	.init_arch		= mcpcia_init_arch,
263 	.init_irq		= rawhide_init_irq,
264 	.init_rtc		= common_init_rtc,
265 	.init_pci		= common_init_pci,
266 	.kill_arch		= NULL,
267 	.pci_map_irq		= rawhide_map_irq,
268 	.pci_swizzle		= common_swizzle,
269 };
270 ALIAS_MV(rawhide)
271