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