1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * linux/arch/alpha/kernel/sys_rx164.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 RX164 (PCA56+POLARIS).
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/dma.h>
22 #include <asm/irq.h>
23 #include <asm/mmu_context.h>
24 #include <asm/io.h>
25 #include <asm/core_polaris.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 /* Note mask bit is true for ENABLED irqs. */
35 static unsigned long cached_irq_mask;
36
37 static inline void
38 rx164_update_irq_hw(unsigned long mask)
39 {
40 volatile unsigned int *irq_mask;
41
42 irq_mask = (void *)(POLARIS_DENSE_CONFIG_BASE + 0x74);
43 *irq_mask = mask;
44 mb();
45 *irq_mask;
46 }
47
48 static inline void
49 rx164_enable_irq(struct irq_data *d)
50 {
51 rx164_update_irq_hw(cached_irq_mask |= 1UL << (d->irq - 16));
52 }
53
54 static void
55 rx164_disable_irq(struct irq_data *d)
56 {
57 rx164_update_irq_hw(cached_irq_mask &= ~(1UL << (d->irq - 16)));
58 }
59
60 static struct irq_chip rx164_irq_type = {
61 .name = "RX164",
62 .irq_unmask = rx164_enable_irq,
63 .irq_mask = rx164_disable_irq,
64 .irq_mask_ack = rx164_disable_irq,
65 };
66
67 static void
68 rx164_device_interrupt(unsigned long vector)
69 {
70 unsigned long pld;
71 volatile unsigned int *dirr;
72 long i;
73
74 /* Read the interrupt summary register. On Polaris, this is
75 the DIRR register in PCI config space (offset 0x84). */
76 dirr = (void *)(POLARIS_DENSE_CONFIG_BASE + 0x84);
77 pld = *dirr;
78
79 /*
80 * Now for every possible bit set, work through them and call
81 * the appropriate interrupt handler.
82 */
83 while (pld) {
84 i = ffz(~pld);
85 pld &= pld - 1; /* clear least bit set */
86 if (i == 20) {
87 isa_no_iack_sc_device_interrupt(vector);
88 } else {
89 handle_irq(16+i);
90 }
91 }
92 }
93
94 static void __init
95 rx164_init_irq(void)
96 {
97 long i;
98
99 rx164_update_irq_hw(0);
100 for (i = 16; i < 40; ++i) {
101 irq_set_chip_and_handler(i, &rx164_irq_type, handle_level_irq);
102 irq_set_status_flags(i, IRQ_LEVEL);
103 }
104
105 init_i8259a_irqs();
106 common_init_isa_dma();
107
108 if (request_irq(16 + 20, no_action, 0, "isa-cascade", NULL))
109 pr_err("Failed to register isa-cascade interrupt\n");
110 }
111
112
113 /*
114 * The RX164 changed its interrupt routing between pass1 and pass2...
115 *
116 * PASS1:
117 *
118 * Slot IDSEL INTA INTB INTC INTD
119 * 0 6 5 10 15 20
120 * 1 7 4 9 14 19
121 * 2 5 3 8 13 18
122 * 3 9 2 7 12 17
123 * 4 10 1 6 11 16
124 *
125 * PASS2:
126 * Slot IDSEL INTA INTB INTC INTD
127 * 0 5 1 7 12 17
128 * 1 6 2 8 13 18
129 * 2 8 3 9 14 19
130 * 3 9 4 10 15 20
131 * 4 10 5 11 16 6
132 *
133 */
134
135 /*
136 * IdSel
137 * 5 32 bit PCI option slot 0
138 * 6 64 bit PCI option slot 1
139 * 7 PCI-ISA bridge
140 * 7 64 bit PCI option slot 2
141 * 9 32 bit PCI option slot 3
142 * 10 PCI-PCI bridge
143 *
144 */
145
146 static int
147 rx164_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
148 {
149 #if 0
150 static char irq_tab_pass1[6][5] __initdata = {
151 /*INT INTA INTB INTC INTD */
152 { 16+3, 16+3, 16+8, 16+13, 16+18}, /* IdSel 5, slot 2 */
153 { 16+5, 16+5, 16+10, 16+15, 16+20}, /* IdSel 6, slot 0 */
154 { 16+4, 16+4, 16+9, 16+14, 16+19}, /* IdSel 7, slot 1 */
155 { -1, -1, -1, -1, -1}, /* IdSel 8, PCI/ISA bridge */
156 { 16+2, 16+2, 16+7, 16+12, 16+17}, /* IdSel 9, slot 3 */
157 { 16+1, 16+1, 16+6, 16+11, 16+16}, /* IdSel 10, slot 4 */
158 };
159 #else
160 static char irq_tab[6][5] = {
161 /*INT INTA INTB INTC INTD */
162 { 16+0, 16+0, 16+6, 16+11, 16+16}, /* IdSel 5, slot 0 */
163 { 16+1, 16+1, 16+7, 16+12, 16+17}, /* IdSel 6, slot 1 */
164 { -1, -1, -1, -1, -1}, /* IdSel 7, PCI/ISA bridge */
165 { 16+2, 16+2, 16+8, 16+13, 16+18}, /* IdSel 8, slot 2 */
166 { 16+3, 16+3, 16+9, 16+14, 16+19}, /* IdSel 9, slot 3 */
167 { 16+4, 16+4, 16+10, 16+15, 16+5}, /* IdSel 10, PCI-PCI */
168 };
169 #endif
170 const long min_idsel = 5, max_idsel = 10, irqs_per_slot = 5;
171
172 /* JRP - Need to figure out how to distinguish pass1 from pass2,
173 and use the correct table. */
174 return COMMON_TABLE_LOOKUP;
175 }
176
177
178 /*
179 * The System Vector
180 */
181
182 struct alpha_machine_vector rx164_mv __initmv = {
183 .vector_name = "RX164",
184 DO_EV5_MMU,
185 DO_DEFAULT_RTC,
186 DO_POLARIS_IO,
187 .machine_check = polaris_machine_check,
188 .max_isa_dma_address = ALPHA_MAX_ISA_DMA_ADDRESS,
189 .min_io_address = DEFAULT_IO_BASE,
190 .min_mem_address = DEFAULT_MEM_BASE,
191
192 .nr_irqs = 40,
193 .device_interrupt = rx164_device_interrupt,
194
195 .init_arch = polaris_init_arch,
196 .init_irq = rx164_init_irq,
197 .init_rtc = common_init_rtc,
198 .init_pci = common_init_pci,
199 .kill_arch = NULL,
200 .pci_map_irq = rx164_map_irq,
201 .pci_swizzle = common_swizzle,
202 };
203 ALIAS_MV(rx164)
204
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.