xref: /openbmc/linux/arch/alpha/kernel/sys_mikasa.c (revision bbecb07f)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *	linux/arch/alpha/kernel/sys_mikasa.c
4  *
5  *	Copyright (C) 1995 David A Rusling
6  *	Copyright (C) 1996 Jay A Estabrook
7  *	Copyright (C) 1998, 1999 Richard Henderson
8  *
9  * Code supporting the MIKASA (AlphaServer 1000).
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/bitops.h>
19 
20 #include <asm/ptrace.h>
21 #include <asm/mce.h>
22 #include <asm/dma.h>
23 #include <asm/irq.h>
24 #include <asm/mmu_context.h>
25 #include <asm/io.h>
26 #include <asm/pgtable.h>
27 #include <asm/core_apecs.h>
28 #include <asm/core_cia.h>
29 #include <asm/tlbflush.h>
30 
31 #include "proto.h"
32 #include "irq_impl.h"
33 #include "pci_impl.h"
34 #include "machvec_impl.h"
35 
36 
37 /* Note mask bit is true for ENABLED irqs.  */
38 static int cached_irq_mask;
39 
40 static inline void
41 mikasa_update_irq_hw(int mask)
42 {
43 	outw(mask, 0x536);
44 }
45 
46 static inline void
47 mikasa_enable_irq(struct irq_data *d)
48 {
49 	mikasa_update_irq_hw(cached_irq_mask |= 1 << (d->irq - 16));
50 }
51 
52 static void
53 mikasa_disable_irq(struct irq_data *d)
54 {
55 	mikasa_update_irq_hw(cached_irq_mask &= ~(1 << (d->irq - 16)));
56 }
57 
58 static struct irq_chip mikasa_irq_type = {
59 	.name		= "MIKASA",
60 	.irq_unmask	= mikasa_enable_irq,
61 	.irq_mask	= mikasa_disable_irq,
62 	.irq_mask_ack	= mikasa_disable_irq,
63 };
64 
65 static void
66 mikasa_device_interrupt(unsigned long vector)
67 {
68 	unsigned long pld;
69 	unsigned int i;
70 
71 	/* Read the interrupt summary registers */
72 	pld = (((~inw(0x534) & 0x0000ffffUL) << 16)
73 	       | (((unsigned long) inb(0xa0)) << 8)
74 	       | inb(0x20));
75 
76 	/*
77 	 * Now for every possible bit set, work through them and call
78 	 * the appropriate interrupt handler.
79 	 */
80 	while (pld) {
81 		i = ffz(~pld);
82 		pld &= pld - 1; /* clear least bit set */
83 		if (i < 16) {
84 			isa_device_interrupt(vector);
85 		} else {
86 			handle_irq(i);
87 		}
88 	}
89 }
90 
91 static void __init
92 mikasa_init_irq(void)
93 {
94 	long i;
95 
96 	if (alpha_using_srm)
97 		alpha_mv.device_interrupt = srm_device_interrupt;
98 
99 	mikasa_update_irq_hw(0);
100 
101 	for (i = 16; i < 32; ++i) {
102 		irq_set_chip_and_handler(i, &mikasa_irq_type,
103 					 handle_level_irq);
104 		irq_set_status_flags(i, IRQ_LEVEL);
105 	}
106 
107 	init_i8259a_irqs();
108 	common_init_isa_dma();
109 }
110 
111 
112 /*
113  * PCI Fixup configuration.
114  *
115  * Summary @ 0x536:
116  * Bit      Meaning
117  * 0        Interrupt Line A from slot 0
118  * 1        Interrupt Line B from slot 0
119  * 2        Interrupt Line C from slot 0
120  * 3        Interrupt Line D from slot 0
121  * 4        Interrupt Line A from slot 1
122  * 5        Interrupt line B from slot 1
123  * 6        Interrupt Line C from slot 1
124  * 7        Interrupt Line D from slot 1
125  * 8        Interrupt Line A from slot 2
126  * 9        Interrupt Line B from slot 2
127  *10        Interrupt Line C from slot 2
128  *11        Interrupt Line D from slot 2
129  *12        NCR 810 SCSI
130  *13        Power Supply Fail
131  *14        Temperature Warn
132  *15        Reserved
133  *
134  * The device to slot mapping looks like:
135  *
136  * Slot     Device
137  *  6       NCR SCSI controller
138  *  7       Intel PCI-EISA bridge chip
139  * 11       PCI on board slot 0
140  * 12       PCI on board slot 1
141  * 13       PCI on board slot 2
142  *
143  *
144  * This two layered interrupt approach means that we allocate IRQ 16 and
145  * above for PCI interrupts.  The IRQ relates to which bit the interrupt
146  * comes in on.  This makes interrupt processing much easier.
147  */
148 
149 static int
150 mikasa_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
151 {
152 	static char irq_tab[8][5] = {
153 		/*INT    INTA   INTB   INTC   INTD */
154 		{16+12, 16+12, 16+12, 16+12, 16+12},	/* IdSel 17,  SCSI */
155 		{   -1,    -1,    -1,    -1,    -1},	/* IdSel 18,  PCEB */
156 		{   -1,    -1,    -1,    -1,    -1},	/* IdSel 19,  ???? */
157 		{   -1,    -1,    -1,    -1,    -1},	/* IdSel 20,  ???? */
158 		{   -1,    -1,    -1,    -1,    -1},	/* IdSel 21,  ???? */
159 		{ 16+0,  16+0,  16+1,  16+2,  16+3},	/* IdSel 22,  slot 0 */
160 		{ 16+4,  16+4,  16+5,  16+6,  16+7},	/* IdSel 23,  slot 1 */
161 		{ 16+8,  16+8,  16+9, 16+10, 16+11},	/* IdSel 24,  slot 2 */
162 	};
163 	const long min_idsel = 6, max_idsel = 13, irqs_per_slot = 5;
164 	return COMMON_TABLE_LOOKUP;
165 }
166 
167 
168 #if defined(CONFIG_ALPHA_GENERIC) || !defined(CONFIG_ALPHA_PRIMO)
169 static void
170 mikasa_apecs_machine_check(unsigned long vector, unsigned long la_ptr)
171 {
172 #define MCHK_NO_DEVSEL 0x205U
173 #define MCHK_NO_TABT 0x204U
174 
175 	struct el_common *mchk_header;
176 	unsigned int code;
177 
178 	mchk_header = (struct el_common *)la_ptr;
179 
180 	/* Clear the error before any reporting.  */
181 	mb();
182 	mb(); /* magic */
183 	draina();
184 	apecs_pci_clr_err();
185 	wrmces(0x7);
186 	mb();
187 
188 	code = mchk_header->code;
189 	process_mcheck_info(vector, la_ptr, "MIKASA APECS",
190 			    (mcheck_expected(0)
191 			     && (code == MCHK_NO_DEVSEL
192 			         || code == MCHK_NO_TABT)));
193 }
194 #endif
195 
196 
197 /*
198  * The System Vector
199  */
200 
201 #if defined(CONFIG_ALPHA_GENERIC) || !defined(CONFIG_ALPHA_PRIMO)
202 struct alpha_machine_vector mikasa_mv __initmv = {
203 	.vector_name		= "Mikasa",
204 	DO_EV4_MMU,
205 	DO_DEFAULT_RTC,
206 	DO_APECS_IO,
207 	.machine_check		= mikasa_apecs_machine_check,
208 	.max_isa_dma_address	= ALPHA_MAX_ISA_DMA_ADDRESS,
209 	.min_io_address		= DEFAULT_IO_BASE,
210 	.min_mem_address	= APECS_AND_LCA_DEFAULT_MEM_BASE,
211 
212 	.nr_irqs		= 32,
213 	.device_interrupt	= mikasa_device_interrupt,
214 
215 	.init_arch		= apecs_init_arch,
216 	.init_irq		= mikasa_init_irq,
217 	.init_rtc		= common_init_rtc,
218 	.init_pci		= common_init_pci,
219 	.pci_map_irq		= mikasa_map_irq,
220 	.pci_swizzle		= common_swizzle,
221 };
222 ALIAS_MV(mikasa)
223 #endif
224 
225 #if defined(CONFIG_ALPHA_GENERIC) || defined(CONFIG_ALPHA_PRIMO)
226 struct alpha_machine_vector mikasa_primo_mv __initmv = {
227 	.vector_name		= "Mikasa-Primo",
228 	DO_EV5_MMU,
229 	DO_DEFAULT_RTC,
230 	DO_CIA_IO,
231 	.machine_check		= cia_machine_check,
232 	.max_isa_dma_address	= ALPHA_MAX_ISA_DMA_ADDRESS,
233 	.min_io_address		= DEFAULT_IO_BASE,
234 	.min_mem_address	= CIA_DEFAULT_MEM_BASE,
235 
236 	.nr_irqs		= 32,
237 	.device_interrupt	= mikasa_device_interrupt,
238 
239 	.init_arch		= cia_init_arch,
240 	.init_irq		= mikasa_init_irq,
241 	.init_rtc		= common_init_rtc,
242 	.init_pci		= cia_init_pci,
243 	.kill_arch		= cia_kill_arch,
244 	.pci_map_irq		= mikasa_map_irq,
245 	.pci_swizzle		= common_swizzle,
246 };
247 ALIAS_MV(mikasa_primo)
248 #endif
249