xref: /openbmc/linux/arch/alpha/kernel/sys_rawhide.c (revision df2634f43f5106947f3735a0b61a6527a4b278cd)
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 #define hose_exists(h) \
56   (((h) < MCPCIA_MAX_HOSES) && (cached_irq_masks[(h)] != 0))
57 
58 static inline void
59 rawhide_enable_irq(unsigned int irq)
60 {
61 	unsigned int mask, hose;
62 
63 	irq -= 16;
64 	hose = irq / 24;
65 	if (!hose_exists(hose)) /* if hose non-existent, exit */
66 		return;
67 
68 	irq -= hose * 24;
69 	mask = 1 << irq;
70 
71 	spin_lock(&rawhide_irq_lock);
72 	mask |= cached_irq_masks[hose];
73 	cached_irq_masks[hose] = mask;
74 	rawhide_update_irq_hw(hose, mask);
75 	spin_unlock(&rawhide_irq_lock);
76 }
77 
78 static void
79 rawhide_disable_irq(unsigned int irq)
80 {
81 	unsigned int mask, hose;
82 
83 	irq -= 16;
84 	hose = irq / 24;
85 	if (!hose_exists(hose)) /* if hose non-existent, exit */
86 		return;
87 
88 	irq -= hose * 24;
89 	mask = ~(1 << irq) | hose_irq_masks[hose];
90 
91 	spin_lock(&rawhide_irq_lock);
92 	mask &= cached_irq_masks[hose];
93 	cached_irq_masks[hose] = mask;
94 	rawhide_update_irq_hw(hose, mask);
95 	spin_unlock(&rawhide_irq_lock);
96 }
97 
98 static void
99 rawhide_mask_and_ack_irq(unsigned int irq)
100 {
101 	unsigned int mask, mask1, hose;
102 
103 	irq -= 16;
104 	hose = irq / 24;
105 	if (!hose_exists(hose)) /* if hose non-existent, exit */
106 		return;
107 
108 	irq -= hose * 24;
109 	mask1 = 1 << irq;
110 	mask = ~mask1 | hose_irq_masks[hose];
111 
112 	spin_lock(&rawhide_irq_lock);
113 
114 	mask &= cached_irq_masks[hose];
115 	cached_irq_masks[hose] = mask;
116 	rawhide_update_irq_hw(hose, mask);
117 
118 	/* Clear the interrupt.  */
119 	*(vuip)MCPCIA_INT_REQ(MCPCIA_HOSE2MID(hose)) = mask1;
120 
121 	spin_unlock(&rawhide_irq_lock);
122 }
123 
124 static struct irq_chip rawhide_irq_type = {
125 	.name		= "RAWHIDE",
126 	.unmask		= rawhide_enable_irq,
127 	.mask		= rawhide_disable_irq,
128 	.mask_ack	= rawhide_mask_and_ack_irq,
129 };
130 
131 static void
132 rawhide_srm_device_interrupt(unsigned long vector)
133 {
134 	int irq;
135 
136 	irq = (vector - 0x800) >> 4;
137 
138         /*
139          * The RAWHIDE SRM console reports PCI interrupts with a vector
140 	 * 0x80 *higher* than one might expect, as PCI IRQ 0 (ie bit 0)
141 	 * shows up as IRQ 24, etc, etc. We adjust it down by 8 to have
142 	 * it line up with the actual bit numbers from the REQ registers,
143 	 * which is how we manage the interrupts/mask. Sigh...
144 	 *
145 	 * Also, PCI #1 interrupts are offset some more... :-(
146          */
147 
148 	if (irq == 52) {
149 		/* SCSI on PCI1 is special.  */
150 		irq = 72;
151 	}
152 
153 	/* Adjust by which hose it is from.  */
154 	irq -= ((irq + 16) >> 2) & 0x38;
155 
156 	handle_irq(irq);
157 }
158 
159 static void __init
160 rawhide_init_irq(void)
161 {
162 	struct pci_controller *hose;
163 	long i;
164 
165 	mcpcia_init_hoses();
166 
167 	/* Clear them all; only hoses that exist will be non-zero. */
168 	for (i = 0; i < MCPCIA_MAX_HOSES; i++) cached_irq_masks[i] = 0;
169 
170 	for (hose = hose_head; hose; hose = hose->next) {
171 		unsigned int h = hose->index;
172 		unsigned int mask = hose_irq_masks[h];
173 
174 		cached_irq_masks[h] = mask;
175 		*(vuip)MCPCIA_INT_MASK0(MCPCIA_HOSE2MID(h)) = mask;
176 		*(vuip)MCPCIA_INT_MASK1(MCPCIA_HOSE2MID(h)) = 0;
177 	}
178 
179 	for (i = 16; i < 128; ++i) {
180 		irq_to_desc(i)->status |= IRQ_LEVEL;
181 		set_irq_chip_and_handler(i, &rawhide_irq_type, handle_level_irq);
182 	}
183 
184 	init_i8259a_irqs();
185 	common_init_isa_dma();
186 }
187 
188 /*
189  * PCI Fixup configuration.
190  *
191  * Summary @ MCPCIA_PCI0_INT_REQ:
192  * Bit      Meaning
193  * 0        Interrupt Line A from slot 2 PCI0
194  * 1        Interrupt Line B from slot 2 PCI0
195  * 2        Interrupt Line C from slot 2 PCI0
196  * 3        Interrupt Line D from slot 2 PCI0
197  * 4        Interrupt Line A from slot 3 PCI0
198  * 5        Interrupt Line B from slot 3 PCI0
199  * 6        Interrupt Line C from slot 3 PCI0
200  * 7        Interrupt Line D from slot 3 PCI0
201  * 8        Interrupt Line A from slot 4 PCI0
202  * 9        Interrupt Line B from slot 4 PCI0
203  * 10       Interrupt Line C from slot 4 PCI0
204  * 11       Interrupt Line D from slot 4 PCI0
205  * 12       Interrupt Line A from slot 5 PCI0
206  * 13       Interrupt Line B from slot 5 PCI0
207  * 14       Interrupt Line C from slot 5 PCI0
208  * 15       Interrupt Line D from slot 5 PCI0
209  * 16       EISA interrupt (PCI 0) or SCSI interrupt (PCI 1)
210  * 17-23    NA
211  *
212  * IdSel
213  *   1	 EISA bridge (PCI bus 0 only)
214  *   2 	 PCI option slot 2
215  *   3	 PCI option slot 3
216  *   4   PCI option slot 4
217  *   5   PCI option slot 5
218  *
219  */
220 
221 static int __init
222 rawhide_map_irq(struct pci_dev *dev, u8 slot, u8 pin)
223 {
224 	static char irq_tab[5][5] __initdata = {
225 		/*INT    INTA   INTB   INTC   INTD */
226 		{ 16+16, 16+16, 16+16, 16+16, 16+16}, /* IdSel 1 SCSI PCI 1 */
227 		{ 16+ 0, 16+ 0, 16+ 1, 16+ 2, 16+ 3}, /* IdSel 2 slot 2 */
228 		{ 16+ 4, 16+ 4, 16+ 5, 16+ 6, 16+ 7}, /* IdSel 3 slot 3 */
229 		{ 16+ 8, 16+ 8, 16+ 9, 16+10, 16+11}, /* IdSel 4 slot 4 */
230 		{ 16+12, 16+12, 16+13, 16+14, 16+15}  /* IdSel 5 slot 5 */
231 	};
232 	const long min_idsel = 1, max_idsel = 5, irqs_per_slot = 5;
233 
234 	struct pci_controller *hose = dev->sysdata;
235 	int irq = COMMON_TABLE_LOOKUP;
236 	if (irq >= 0)
237 		irq += 24 * hose->index;
238 	return irq;
239 }
240 
241 
242 /*
243  * The System Vector
244  */
245 
246 struct alpha_machine_vector rawhide_mv __initmv = {
247 	.vector_name		= "Rawhide",
248 	DO_EV5_MMU,
249 	DO_DEFAULT_RTC,
250 	DO_MCPCIA_IO,
251 	.machine_check		= mcpcia_machine_check,
252 	.max_isa_dma_address	= ALPHA_MAX_ISA_DMA_ADDRESS,
253 	.min_io_address		= DEFAULT_IO_BASE,
254 	.min_mem_address	= MCPCIA_DEFAULT_MEM_BASE,
255 	.pci_dac_offset		= MCPCIA_DAC_OFFSET,
256 
257 	.nr_irqs		= 128,
258 	.device_interrupt	= rawhide_srm_device_interrupt,
259 
260 	.init_arch		= mcpcia_init_arch,
261 	.init_irq		= rawhide_init_irq,
262 	.init_rtc		= common_init_rtc,
263 	.init_pci		= common_init_pci,
264 	.kill_arch		= NULL,
265 	.pci_map_irq		= rawhide_map_irq,
266 	.pci_swizzle		= common_swizzle,
267 };
268 ALIAS_MV(rawhide)
269