xref: /linux/arch/alpha/kernel/sys_cabriolet.c (revision 594ce0b8a998aa4d05827cd7c0d0dcec9a1e3ae2)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *	linux/arch/alpha/kernel/sys_cabriolet.c
4  *
5  *	Copyright (C) 1995 David A Rusling
6  *	Copyright (C) 1996 Jay A Estabrook
7  *	Copyright (C) 1998, 1999, 2000 Richard Henderson
8  *
9  * Code supporting the PC164 and LX164.
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_cia.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 #include "pc873xx.h"
33 
34 /* Note mask bit is true for DISABLED irqs.  */
35 static unsigned long cached_irq_mask = ~0UL;
36 
37 static inline void
38 cabriolet_update_irq_hw(unsigned int irq, unsigned long mask)
39 {
40 	int ofs = (irq - 16) / 8;
41 	outb(mask >> (16 + ofs * 8), 0x804 + ofs);
42 }
43 
44 static inline void
45 cabriolet_enable_irq(struct irq_data *d)
46 {
47 	cabriolet_update_irq_hw(d->irq, cached_irq_mask &= ~(1UL << d->irq));
48 }
49 
50 static void
51 cabriolet_disable_irq(struct irq_data *d)
52 {
53 	cabriolet_update_irq_hw(d->irq, cached_irq_mask |= 1UL << d->irq);
54 }
55 
56 static struct irq_chip cabriolet_irq_type = {
57 	.name		= "CABRIOLET",
58 	.irq_unmask	= cabriolet_enable_irq,
59 	.irq_mask	= cabriolet_disable_irq,
60 	.irq_mask_ack	= cabriolet_disable_irq,
61 };
62 
63 static void
64 cabriolet_device_interrupt(unsigned long v)
65 {
66 	unsigned long pld;
67 	unsigned int i;
68 
69 	/* Read the interrupt summary registers */
70 	pld = inb(0x804) | (inb(0x805) << 8) | (inb(0x806) << 16);
71 
72 	/*
73 	 * Now for every possible bit set, work through them and call
74 	 * the appropriate interrupt handler.
75 	 */
76 	while (pld) {
77 		i = ffz(~pld);
78 		pld &= pld - 1;	/* clear least bit set */
79 		if (i == 4) {
80 			isa_device_interrupt(v);
81 		} else {
82 			handle_irq(16 + i);
83 		}
84 	}
85 }
86 
87 static void __init
88 common_init_irq(void (*srm_dev_int)(unsigned long v))
89 {
90 	init_i8259a_irqs();
91 
92 	if (alpha_using_srm) {
93 		alpha_mv.device_interrupt = srm_dev_int;
94 		init_srm_irqs(35, 0);
95 	}
96 	else {
97 		long i;
98 
99 		outb(0xff, 0x804);
100 		outb(0xff, 0x805);
101 		outb(0xff, 0x806);
102 
103 		for (i = 16; i < 35; ++i) {
104 			irq_set_chip_and_handler(i, &cabriolet_irq_type,
105 						 handle_level_irq);
106 			irq_set_status_flags(i, IRQ_LEVEL);
107 		}
108 	}
109 
110 	common_init_isa_dma();
111 	if (request_irq(16 + 4, no_action, 0, "isa-cascade", NULL))
112 		pr_err("Failed to register isa-cascade interrupt\n");
113 }
114 
115 #ifndef CONFIG_ALPHA_PC164
116 static void __init
117 cabriolet_init_irq(void)
118 {
119 	common_init_irq(srm_device_interrupt);
120 }
121 #endif
122 
123 #if defined(CONFIG_ALPHA_GENERIC) || defined(CONFIG_ALPHA_PC164)
124 /* In theory, the PC164 has the same interrupt hardware as the other
125    Cabriolet based systems.  However, something got screwed up late
126    in the development cycle which broke the interrupt masking hardware.
127    Repeat, it is not possible to mask and ack interrupts.  At all.
128 
129    In an attempt to work around this, while processing interrupts,
130    we do not allow the IPL to drop below what it is currently.  This
131    prevents the possibility of recursion.
132 
133    ??? Another option might be to force all PCI devices to use edge
134    triggered rather than level triggered interrupts.  That might be
135    too invasive though.  */
136 
137 static void
138 pc164_srm_device_interrupt(unsigned long v)
139 {
140 	__min_ipl = getipl();
141 	srm_device_interrupt(v);
142 	__min_ipl = 0;
143 }
144 
145 static void
146 pc164_device_interrupt(unsigned long v)
147 {
148 	__min_ipl = getipl();
149 	cabriolet_device_interrupt(v);
150 	__min_ipl = 0;
151 }
152 
153 static void __init
154 pc164_init_irq(void)
155 {
156 	common_init_irq(pc164_srm_device_interrupt);
157 }
158 #endif
159 
160 /*
161  * The EB66+ is very similar to the EB66 except that it does not have
162  * the on-board NCR and Tulip chips.  In the code below, I have used
163  * slot number to refer to the id select line and *not* the slot
164  * number used in the EB66+ documentation.  However, in the table,
165  * I've given the slot number, the id select line and the Jxx number
166  * that's printed on the board.  The interrupt pins from the PCI slots
167  * are wired into 3 interrupt summary registers at 0x804, 0x805 and
168  * 0x806 ISA.
169  *
170  * In the table, -1 means don't assign an IRQ number.  This is usually
171  * because it is the Saturn IO (SIO) PCI/ISA Bridge Chip.
172  */
173 
174 static inline int
175 eb66p_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
176 {
177 	static char irq_tab[5][5] = {
178 		/*INT  INTA  INTB  INTC   INTD */
179 		{16+0, 16+0, 16+5,  16+9, 16+13},  /* IdSel 6,  slot 0, J25 */
180 		{16+1, 16+1, 16+6, 16+10, 16+14},  /* IdSel 7,  slot 1, J26 */
181 		{  -1,   -1,   -1,    -1,    -1},  /* IdSel 8,  SIO         */
182 		{16+2, 16+2, 16+7, 16+11, 16+15},  /* IdSel 9,  slot 2, J27 */
183 		{16+3, 16+3, 16+8, 16+12,  16+6}   /* IdSel 10, slot 3, J28 */
184 	};
185 	const long min_idsel = 6, max_idsel = 10, irqs_per_slot = 5;
186 	return COMMON_TABLE_LOOKUP;
187 }
188 
189 
190 /*
191  * The AlphaPC64 is very similar to the EB66+ except that its slots
192  * are numbered differently.  In the code below, I have used slot
193  * number to refer to the id select line and *not* the slot number
194  * used in the AlphaPC64 documentation.  However, in the table, I've
195  * given the slot number, the id select line and the Jxx number that's
196  * printed on the board.  The interrupt pins from the PCI slots are
197  * wired into 3 interrupt summary registers at 0x804, 0x805 and 0x806
198  * ISA.
199  *
200  * In the table, -1 means don't assign an IRQ number.  This is usually
201  * because it is the Saturn IO (SIO) PCI/ISA Bridge Chip.
202  */
203 
204 static inline int
205 cabriolet_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
206 {
207 	static char irq_tab[5][5] = {
208 		/*INT   INTA  INTB  INTC   INTD */
209 		{ 16+2, 16+2, 16+7, 16+11, 16+15}, /* IdSel 5,  slot 2, J21 */
210 		{ 16+0, 16+0, 16+5,  16+9, 16+13}, /* IdSel 6,  slot 0, J19 */
211 		{ 16+1, 16+1, 16+6, 16+10, 16+14}, /* IdSel 7,  slot 1, J20 */
212 		{   -1,   -1,   -1,    -1,    -1}, /* IdSel 8,  SIO         */
213 		{ 16+3, 16+3, 16+8, 16+12, 16+16}  /* IdSel 9,  slot 3, J22 */
214 	};
215 	const long min_idsel = 5, max_idsel = 9, irqs_per_slot = 5;
216 	return COMMON_TABLE_LOOKUP;
217 }
218 
219 static inline void __init
220 cabriolet_enable_ide(void)
221 {
222 	if (pc873xx_probe() == -1) {
223 		printk(KERN_ERR "Probing for PC873xx Super IO chip failed.\n");
224 	 } else {
225 		printk(KERN_INFO "Found %s Super IO chip at 0x%x\n",
226 			pc873xx_get_model(), pc873xx_get_base());
227 
228 		pc873xx_enable_ide();
229 	}
230 }
231 
232 static inline void __init
233 cia_cab_init_pci(void)
234 {
235 	cia_init_pci();
236 	cabriolet_enable_ide();
237 }
238 
239 /*
240  * The PC164 and LX164 have 19 PCI interrupts, four from each of the four
241  * PCI slots, the SIO, PCI/IDE, and USB.
242  *
243  * Each of the interrupts can be individually masked. This is
244  * accomplished by setting the appropriate bit in the mask register.
245  * A bit is set by writing a "1" to the desired position in the mask
246  * register and cleared by writing a "0". There are 3 mask registers
247  * located at ISA address 804h, 805h and 806h.
248  *
249  * An I/O read at ISA address 804h, 805h, 806h will return the
250  * state of the 11 PCI interrupts and not the state of the MASKED
251  * interrupts.
252  *
253  * Note: A write to I/O 804h, 805h, and 806h the mask register will be
254  * updated.
255  *
256  *
257  * 				ISA DATA<7:0>
258  * ISA     +--------------------------------------------------------------+
259  * ADDRESS |   7   |   6   |   5   |   4   |   3   |   2  |   1   |   0   |
260  *         +==============================================================+
261  * 0x804   | INTB0 |  USB  |  IDE  |  SIO  | INTA3 |INTA2 | INTA1 | INTA0 |
262  *         +--------------------------------------------------------------+
263  * 0x805   | INTD0 | INTC3 | INTC2 | INTC1 | INTC0 |INTB3 | INTB2 | INTB1 |
264  *         +--------------------------------------------------------------+
265  * 0x806   | Rsrv  | Rsrv  | Rsrv  | Rsrv  | Rsrv  |INTD3 | INTD2 | INTD1 |
266  *         +--------------------------------------------------------------+
267  *         * Rsrv = reserved bits
268  *         Note: The mask register is write-only.
269  *
270  * IdSel
271  *   5	 32 bit PCI option slot 2
272  *   6	 64 bit PCI option slot 0
273  *   7	 64 bit PCI option slot 1
274  *   8	 Saturn I/O
275  *   9	 32 bit PCI option slot 3
276  *  10	 USB
277  *  11	 IDE
278  *
279  */
280 
281 static inline int
282 alphapc164_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
283 {
284 	static char irq_tab[7][5] = {
285 		/*INT   INTA  INTB   INTC   INTD */
286 		{ 16+2, 16+2, 16+9,  16+13, 16+17}, /* IdSel  5, slot 2, J20 */
287 		{ 16+0, 16+0, 16+7,  16+11, 16+15}, /* IdSel  6, slot 0, J29 */
288 		{ 16+1, 16+1, 16+8,  16+12, 16+16}, /* IdSel  7, slot 1, J26 */
289 		{   -1,   -1,   -1,    -1,    -1},  /* IdSel  8, SIO */
290 		{ 16+3, 16+3, 16+10, 16+14, 16+18}, /* IdSel  9, slot 3, J19 */
291 		{ 16+6, 16+6, 16+6,  16+6,  16+6},  /* IdSel 10, USB */
292 		{ 16+5, 16+5, 16+5,  16+5,  16+5}   /* IdSel 11, IDE */
293 	};
294 	const long min_idsel = 5, max_idsel = 11, irqs_per_slot = 5;
295 	return COMMON_TABLE_LOOKUP;
296 }
297 
298 static inline void __init
299 alphapc164_init_pci(void)
300 {
301 	cia_init_pci();
302 	SMC93x_Init();
303 }
304 
305 
306 /*
307  * The System Vector
308  */
309 
310 #if defined(CONFIG_ALPHA_GENERIC) || defined(CONFIG_ALPHA_LX164)
311 struct alpha_machine_vector lx164_mv __initmv = {
312 	.vector_name		= "LX164",
313 	DO_EV5_MMU,
314 	DO_DEFAULT_RTC,
315 	DO_PYXIS_IO,
316 	.machine_check		= cia_machine_check,
317 	.max_isa_dma_address	= ALPHA_MAX_ISA_DMA_ADDRESS,
318 	.min_io_address		= DEFAULT_IO_BASE,
319 	.min_mem_address	= DEFAULT_MEM_BASE,
320 	.pci_dac_offset		= PYXIS_DAC_OFFSET,
321 
322 	.nr_irqs		= 35,
323 	.device_interrupt	= cabriolet_device_interrupt,
324 
325 	.init_arch		= pyxis_init_arch,
326 	.init_irq		= cabriolet_init_irq,
327 	.init_rtc		= common_init_rtc,
328 	.init_pci		= alphapc164_init_pci,
329 	.kill_arch		= cia_kill_arch,
330 	.pci_map_irq		= alphapc164_map_irq,
331 	.pci_swizzle		= common_swizzle,
332 };
333 ALIAS_MV(lx164)
334 #endif
335 
336 #if defined(CONFIG_ALPHA_GENERIC) || defined(CONFIG_ALPHA_PC164)
337 struct alpha_machine_vector pc164_mv __initmv = {
338 	.vector_name		= "PC164",
339 	DO_EV5_MMU,
340 	DO_DEFAULT_RTC,
341 	DO_CIA_IO,
342 	.machine_check		= cia_machine_check,
343 	.max_isa_dma_address	= ALPHA_MAX_ISA_DMA_ADDRESS,
344 	.min_io_address		= DEFAULT_IO_BASE,
345 	.min_mem_address	= CIA_DEFAULT_MEM_BASE,
346 
347 	.nr_irqs		= 35,
348 	.device_interrupt	= pc164_device_interrupt,
349 
350 	.init_arch		= cia_init_arch,
351 	.init_irq		= pc164_init_irq,
352 	.init_rtc		= common_init_rtc,
353 	.init_pci		= alphapc164_init_pci,
354 	.kill_arch		= cia_kill_arch,
355 	.pci_map_irq		= alphapc164_map_irq,
356 	.pci_swizzle		= common_swizzle,
357 };
358 ALIAS_MV(pc164)
359 #endif
360