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authorGeert Uytterhoeven <geert@linux-m68k.org>2011-08-18 13:36:30 -0400
committerGeert Uytterhoeven <geert@linux-m68k.org>2011-11-08 16:35:49 -0500
commit34971bad3a1511db7b76eeb2337819967a135075 (patch)
tree01968f8edbc78a19e2b75088946da566d5fc1d57 /arch/m68k/atari
parente59629ddc6eddbd00e81b4afb814583cfcc4706d (diff)
m68k/atari: Remove code and comments about different irq types
This code was obsoleted during the irq restructuring in 2006. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Diffstat (limited to 'arch/m68k/atari')
-rw-r--r--arch/m68k/atari/ataints.c236
1 files changed, 0 insertions, 236 deletions
diff --git a/arch/m68k/atari/ataints.c b/arch/m68k/atari/ataints.c
index 6149ff994641..af544557dd1d 100644
--- a/arch/m68k/atari/ataints.c
+++ b/arch/m68k/atari/ataints.c
@@ -60,244 +60,8 @@
60 * <asm/atariints.h>): Autovector interrupts are 1..7, then follow ST-MFP, 60 * <asm/atariints.h>): Autovector interrupts are 1..7, then follow ST-MFP,
61 * TT-MFP, SCC, and finally VME interrupts. Vector numbers for the latter can 61 * TT-MFP, SCC, and finally VME interrupts. Vector numbers for the latter can
62 * be allocated by atari_register_vme_int(). 62 * be allocated by atari_register_vme_int().
63 *
64 * Each interrupt can be of three types:
65 *
66 * - SLOW: The handler runs with all interrupts enabled, except the one it
67 * was called by (to avoid reentering). This should be the usual method.
68 * But it is currently possible only for MFP ints, since only the MFP
69 * offers an easy way to mask interrupts.
70 *
71 * - FAST: The handler runs with all interrupts disabled. This should be used
72 * only for really fast handlers, that just do actions immediately
73 * necessary, and let the rest do a bottom half or task queue.
74 *
75 * - PRIORITIZED: The handler can be interrupted by higher-level ints
76 * (greater IPL, no MFP priorities!). This is the method of choice for ints
77 * which should be slow, but are not from a MFP.
78 *
79 * The feature of more than one handler for one int source is still there, but
80 * only applicable if all handers are of the same type. To not slow down
81 * processing of ints with only one handler by the chaining feature, the list
82 * calling function atari_call_irq_list() is only plugged in at the time the
83 * second handler is registered.
84 *
85 * Implementation notes: For fast-as-possible int handling, there are separate
86 * entry points for each type (slow/fast/prio). The assembler handler calls
87 * the irq directly in the usual case, no C wrapper is involved. In case of
88 * multiple handlers, atari_call_irq_list() is registered as handler and calls
89 * in turn the real irq's. To ease access from assembler level to the irq
90 * function pointer and accompanying data, these two are stored in a separate
91 * array, irq_handler[]. The rest of data (type, name) are put into a second
92 * array, irq_param, that is accessed from C only. For each slow interrupt (32
93 * in all) there are separate handler functions, which makes it possible to
94 * hard-code the MFP register address and value, are necessary to mask the
95 * int. If there'd be only one generic function, lots of calculations would be
96 * needed to determine MFP register and int mask from the vector number :-(
97 *
98 * Furthermore, slow ints may not lower the IPL below its previous value
99 * (before the int happened). This is needed so that an int of class PRIO, on
100 * that this int may be stacked, cannot be reentered. This feature is
101 * implemented as follows: If the stack frame format is 1 (throwaway), the int
102 * is not stacked, and the IPL is anded with 0xfbff, resulting in a new level
103 * 2, which still blocks the HSYNC, but no interrupts of interest. If the
104 * frame format is 0, the int is nested, and the old IPL value can be found in
105 * the sr copy in the frame.
106 */ 63 */
107 64
108#if 0
109
110#define NUM_INT_SOURCES (8 + NUM_ATARI_SOURCES)
111
112typedef void (*asm_irq_handler)(void);
113
114struct irqhandler {
115 irqreturn_t (*handler)(int, void *, struct pt_regs *);
116 void *dev_id;
117};
118
119struct irqparam {
120 unsigned long flags;
121 const char *devname;
122};
123
124/*
125 * Array with irq's and their parameter data. This array is accessed from low
126 * level assembler code, so an element size of 8 allows usage of index scaling
127 * addressing mode.
128 */
129static struct irqhandler irq_handler[NUM_INT_SOURCES];
130
131/*
132 * This array hold the rest of parameters of int handlers: type
133 * (slow,fast,prio) and the name of the handler. These values are only
134 * accessed from C
135 */
136static struct irqparam irq_param[NUM_INT_SOURCES];
137
138/* check for valid int number (complex, sigh...) */
139#define IS_VALID_INTNO(n) \
140 ((n) > 0 && \
141 /* autovec and ST-MFP ok anyway */ \
142 (((n) < TTMFP_SOURCE_BASE) || \
143 /* TT-MFP ok if present */ \
144 ((n) >= TTMFP_SOURCE_BASE && (n) < SCC_SOURCE_BASE && \
145 ATARIHW_PRESENT(TT_MFP)) || \
146 /* SCC ok if present and number even */ \
147 ((n) >= SCC_SOURCE_BASE && (n) < VME_SOURCE_BASE && \
148 !((n) & 1) && ATARIHW_PRESENT(SCC)) || \
149 /* greater numbers ok if they are registered VME vectors */ \
150 ((n) >= VME_SOURCE_BASE && (n) < VME_SOURCE_BASE + VME_MAX_SOURCES && \
151 free_vme_vec_bitmap & (1 << ((n) - VME_SOURCE_BASE)))))
152
153
154/*
155 * Here start the assembler entry points for interrupts
156 */
157
158#define IRQ_NAME(nr) atari_slow_irq_##nr##_handler(void)
159
160#define BUILD_SLOW_IRQ(n) \
161asmlinkage void IRQ_NAME(n); \
162/* Dummy function to allow asm with operands. */ \
163void atari_slow_irq_##n##_dummy (void) { \
164__asm__ (__ALIGN_STR "\n" \
165"atari_slow_irq_" #n "_handler:\t" \
166" addl %6,%5\n" /* preempt_count() += HARDIRQ_OFFSET */ \
167 SAVE_ALL_INT "\n" \
168 GET_CURRENT(%%d0) "\n" \
169" andb #~(1<<(%c3&7)),%a4:w\n" /* mask this interrupt */ \
170 /* get old IPL from stack frame */ \
171" bfextu %%sp@(%c2){#5,#3},%%d0\n" \
172" movew %%sr,%%d1\n" \
173" bfins %%d0,%%d1{#21,#3}\n" \
174" movew %%d1,%%sr\n" /* set IPL = previous value */ \
175" addql #1,%a0\n" \
176" lea %a1,%%a0\n" \
177" pea %%sp@\n" /* push addr of frame */ \
178" movel %%a0@(4),%%sp@-\n" /* push handler data */ \
179" pea (%c3+8)\n" /* push int number */ \
180" movel %%a0@,%%a0\n" \
181" jbsr %%a0@\n" /* call the handler */ \
182" addql #8,%%sp\n" \
183" addql #4,%%sp\n" \
184" orw #0x0600,%%sr\n" \
185" andw #0xfeff,%%sr\n" /* set IPL = 6 again */ \
186" orb #(1<<(%c3&7)),%a4:w\n" /* now unmask the int again */ \
187" jbra ret_from_interrupt\n" \
188 : : "i" (&kstat_cpu(0).irqs[n+8]), "i" (&irq_handler[n+8]), \
189 "n" (PT_OFF_SR), "n" (n), \
190 "i" (n & 8 ? (n & 16 ? &tt_mfp.int_mk_a : &st_mfp.int_mk_a) \
191 : (n & 16 ? &tt_mfp.int_mk_b : &st_mfp.int_mk_b)), \
192 "m" (preempt_count()), "di" (HARDIRQ_OFFSET) \
193); \
194 for (;;); /* fake noreturn */ \
195}
196
197BUILD_SLOW_IRQ(0);
198BUILD_SLOW_IRQ(1);
199BUILD_SLOW_IRQ(2);
200BUILD_SLOW_IRQ(3);
201BUILD_SLOW_IRQ(4);
202BUILD_SLOW_IRQ(5);
203BUILD_SLOW_IRQ(6);
204BUILD_SLOW_IRQ(7);
205BUILD_SLOW_IRQ(8);
206BUILD_SLOW_IRQ(9);
207BUILD_SLOW_IRQ(10);
208BUILD_SLOW_IRQ(11);
209BUILD_SLOW_IRQ(12);
210BUILD_SLOW_IRQ(13);
211BUILD_SLOW_IRQ(14);
212BUILD_SLOW_IRQ(15);
213BUILD_SLOW_IRQ(16);
214BUILD_SLOW_IRQ(17);
215BUILD_SLOW_IRQ(18);
216BUILD_SLOW_IRQ(19);
217BUILD_SLOW_IRQ(20);
218BUILD_SLOW_IRQ(21);
219BUILD_SLOW_IRQ(22);
220BUILD_SLOW_IRQ(23);
221BUILD_SLOW_IRQ(24);
222BUILD_SLOW_IRQ(25);
223BUILD_SLOW_IRQ(26);
224BUILD_SLOW_IRQ(27);
225BUILD_SLOW_IRQ(28);
226BUILD_SLOW_IRQ(29);
227BUILD_SLOW_IRQ(30);
228BUILD_SLOW_IRQ(31);
229
230asm_irq_handler slow_handlers[32] = {
231 [0] = atari_slow_irq_0_handler,
232 [1] = atari_slow_irq_1_handler,
233 [2] = atari_slow_irq_2_handler,
234 [3] = atari_slow_irq_3_handler,
235 [4] = atari_slow_irq_4_handler,
236 [5] = atari_slow_irq_5_handler,
237 [6] = atari_slow_irq_6_handler,
238 [7] = atari_slow_irq_7_handler,
239 [8] = atari_slow_irq_8_handler,
240 [9] = atari_slow_irq_9_handler,
241 [10] = atari_slow_irq_10_handler,
242 [11] = atari_slow_irq_11_handler,
243 [12] = atari_slow_irq_12_handler,
244 [13] = atari_slow_irq_13_handler,
245 [14] = atari_slow_irq_14_handler,
246 [15] = atari_slow_irq_15_handler,
247 [16] = atari_slow_irq_16_handler,
248 [17] = atari_slow_irq_17_handler,
249 [18] = atari_slow_irq_18_handler,
250 [19] = atari_slow_irq_19_handler,
251 [20] = atari_slow_irq_20_handler,
252 [21] = atari_slow_irq_21_handler,
253 [22] = atari_slow_irq_22_handler,
254 [23] = atari_slow_irq_23_handler,
255 [24] = atari_slow_irq_24_handler,
256 [25] = atari_slow_irq_25_handler,
257 [26] = atari_slow_irq_26_handler,
258 [27] = atari_slow_irq_27_handler,
259 [28] = atari_slow_irq_28_handler,
260 [29] = atari_slow_irq_29_handler,
261 [30] = atari_slow_irq_30_handler,
262 [31] = atari_slow_irq_31_handler
263};
264
265asmlinkage void atari_fast_irq_handler( void );
266asmlinkage void atari_prio_irq_handler( void );
267
268/* Dummy function to allow asm with operands. */
269void atari_fast_prio_irq_dummy (void) {
270__asm__ (__ALIGN_STR "\n"
271"atari_fast_irq_handler:\n\t"
272 "orw #0x700,%%sr\n" /* disable all interrupts */
273"atari_prio_irq_handler:\n\t"
274 "addl %3,%2\n\t" /* preempt_count() += HARDIRQ_OFFSET */
275 SAVE_ALL_INT "\n\t"
276 GET_CURRENT(%%d0) "\n\t"
277 /* get vector number from stack frame and convert to source */
278 "bfextu %%sp@(%c1){#4,#10},%%d0\n\t"
279 "subw #(0x40-8),%%d0\n\t"
280 "jpl 1f\n\t"
281 "addw #(0x40-8-0x18),%%d0\n"
282 "1:\tlea %a0,%%a0\n\t"
283 "addql #1,%%a0@(%%d0:l:4)\n\t"
284 "lea irq_handler,%%a0\n\t"
285 "lea %%a0@(%%d0:l:8),%%a0\n\t"
286 "pea %%sp@\n\t" /* push frame address */
287 "movel %%a0@(4),%%sp@-\n\t" /* push handler data */
288 "movel %%d0,%%sp@-\n\t" /* push int number */
289 "movel %%a0@,%%a0\n\t"
290 "jsr %%a0@\n\t" /* and call the handler */
291 "addql #8,%%sp\n\t"
292 "addql #4,%%sp\n\t"
293 "jbra ret_from_interrupt"
294 : : "i" (&kstat_cpu(0).irqs), "n" (PT_OFF_FORMATVEC),
295 "m" (preempt_count()), "di" (HARDIRQ_OFFSET)
296);
297 for (;;);
298}
299#endif
300
301/* 65/*
302 * Bitmap for free interrupt vector numbers 66 * Bitmap for free interrupt vector numbers
303 * (new vectors starting from 0x70 can be allocated by 67 * (new vectors starting from 0x70 can be allocated by
generated by cgit v1.2.2 (git 2.25.0) at 2025-01-21 17:39:24 -0500