From 34971bad3a1511db7b76eeb2337819967a135075 Mon Sep 17 00:00:00 2001 From: Geert Uytterhoeven Date: Thu, 18 Aug 2011 19:36:30 +0200 Subject: 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 --- arch/m68k/atari/ataints.c | 236 ---------------------------------------------- 1 file changed, 236 deletions(-) (limited to 'arch/m68k/atari') 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 @@ * ): Autovector interrupts are 1..7, then follow ST-MFP, * TT-MFP, SCC, and finally VME interrupts. Vector numbers for the latter can * be allocated by atari_register_vme_int(). - * - * Each interrupt can be of three types: - * - * - SLOW: The handler runs with all interrupts enabled, except the one it - * was called by (to avoid reentering). This should be the usual method. - * But it is currently possible only for MFP ints, since only the MFP - * offers an easy way to mask interrupts. - * - * - FAST: The handler runs with all interrupts disabled. This should be used - * only for really fast handlers, that just do actions immediately - * necessary, and let the rest do a bottom half or task queue. - * - * - PRIORITIZED: The handler can be interrupted by higher-level ints - * (greater IPL, no MFP priorities!). This is the method of choice for ints - * which should be slow, but are not from a MFP. - * - * The feature of more than one handler for one int source is still there, but - * only applicable if all handers are of the same type. To not slow down - * processing of ints with only one handler by the chaining feature, the list - * calling function atari_call_irq_list() is only plugged in at the time the - * second handler is registered. - * - * Implementation notes: For fast-as-possible int handling, there are separate - * entry points for each type (slow/fast/prio). The assembler handler calls - * the irq directly in the usual case, no C wrapper is involved. In case of - * multiple handlers, atari_call_irq_list() is registered as handler and calls - * in turn the real irq's. To ease access from assembler level to the irq - * function pointer and accompanying data, these two are stored in a separate - * array, irq_handler[]. The rest of data (type, name) are put into a second - * array, irq_param, that is accessed from C only. For each slow interrupt (32 - * in all) there are separate handler functions, which makes it possible to - * hard-code the MFP register address and value, are necessary to mask the - * int. If there'd be only one generic function, lots of calculations would be - * needed to determine MFP register and int mask from the vector number :-( - * - * Furthermore, slow ints may not lower the IPL below its previous value - * (before the int happened). This is needed so that an int of class PRIO, on - * that this int may be stacked, cannot be reentered. This feature is - * implemented as follows: If the stack frame format is 1 (throwaway), the int - * is not stacked, and the IPL is anded with 0xfbff, resulting in a new level - * 2, which still blocks the HSYNC, but no interrupts of interest. If the - * frame format is 0, the int is nested, and the old IPL value can be found in - * the sr copy in the frame. */ -#if 0 - -#define NUM_INT_SOURCES (8 + NUM_ATARI_SOURCES) - -typedef void (*asm_irq_handler)(void); - -struct irqhandler { - irqreturn_t (*handler)(int, void *, struct pt_regs *); - void *dev_id; -}; - -struct irqparam { - unsigned long flags; - const char *devname; -}; - -/* - * Array with irq's and their parameter data. This array is accessed from low - * level assembler code, so an element size of 8 allows usage of index scaling - * addressing mode. - */ -static struct irqhandler irq_handler[NUM_INT_SOURCES]; - -/* - * This array hold the rest of parameters of int handlers: type - * (slow,fast,prio) and the name of the handler. These values are only - * accessed from C - */ -static struct irqparam irq_param[NUM_INT_SOURCES]; - -/* check for valid int number (complex, sigh...) */ -#define IS_VALID_INTNO(n) \ - ((n) > 0 && \ - /* autovec and ST-MFP ok anyway */ \ - (((n) < TTMFP_SOURCE_BASE) || \ - /* TT-MFP ok if present */ \ - ((n) >= TTMFP_SOURCE_BASE && (n) < SCC_SOURCE_BASE && \ - ATARIHW_PRESENT(TT_MFP)) || \ - /* SCC ok if present and number even */ \ - ((n) >= SCC_SOURCE_BASE && (n) < VME_SOURCE_BASE && \ - !((n) & 1) && ATARIHW_PRESENT(SCC)) || \ - /* greater numbers ok if they are registered VME vectors */ \ - ((n) >= VME_SOURCE_BASE && (n) < VME_SOURCE_BASE + VME_MAX_SOURCES && \ - free_vme_vec_bitmap & (1 << ((n) - VME_SOURCE_BASE))))) - - -/* - * Here start the assembler entry points for interrupts - */ - -#define IRQ_NAME(nr) atari_slow_irq_##nr##_handler(void) - -#define BUILD_SLOW_IRQ(n) \ -asmlinkage void IRQ_NAME(n); \ -/* Dummy function to allow asm with operands. */ \ -void atari_slow_irq_##n##_dummy (void) { \ -__asm__ (__ALIGN_STR "\n" \ -"atari_slow_irq_" #n "_handler:\t" \ -" addl %6,%5\n" /* preempt_count() += HARDIRQ_OFFSET */ \ - SAVE_ALL_INT "\n" \ - GET_CURRENT(%%d0) "\n" \ -" andb #~(1<<(%c3&7)),%a4:w\n" /* mask this interrupt */ \ - /* get old IPL from stack frame */ \ -" bfextu %%sp@(%c2){#5,#3},%%d0\n" \ -" movew %%sr,%%d1\n" \ -" bfins %%d0,%%d1{#21,#3}\n" \ -" movew %%d1,%%sr\n" /* set IPL = previous value */ \ -" addql #1,%a0\n" \ -" lea %a1,%%a0\n" \ -" pea %%sp@\n" /* push addr of frame */ \ -" movel %%a0@(4),%%sp@-\n" /* push handler data */ \ -" pea (%c3+8)\n" /* push int number */ \ -" movel %%a0@,%%a0\n" \ -" jbsr %%a0@\n" /* call the handler */ \ -" addql #8,%%sp\n" \ -" addql #4,%%sp\n" \ -" orw #0x0600,%%sr\n" \ -" andw #0xfeff,%%sr\n" /* set IPL = 6 again */ \ -" orb #(1<<(%c3&7)),%a4:w\n" /* now unmask the int again */ \ -" jbra ret_from_interrupt\n" \ - : : "i" (&kstat_cpu(0).irqs[n+8]), "i" (&irq_handler[n+8]), \ - "n" (PT_OFF_SR), "n" (n), \ - "i" (n & 8 ? (n & 16 ? &tt_mfp.int_mk_a : &st_mfp.int_mk_a) \ - : (n & 16 ? &tt_mfp.int_mk_b : &st_mfp.int_mk_b)), \ - "m" (preempt_count()), "di" (HARDIRQ_OFFSET) \ -); \ - for (;;); /* fake noreturn */ \ -} - -BUILD_SLOW_IRQ(0); -BUILD_SLOW_IRQ(1); -BUILD_SLOW_IRQ(2); -BUILD_SLOW_IRQ(3); -BUILD_SLOW_IRQ(4); -BUILD_SLOW_IRQ(5); -BUILD_SLOW_IRQ(6); -BUILD_SLOW_IRQ(7); -BUILD_SLOW_IRQ(8); -BUILD_SLOW_IRQ(9); -BUILD_SLOW_IRQ(10); -BUILD_SLOW_IRQ(11); -BUILD_SLOW_IRQ(12); -BUILD_SLOW_IRQ(13); -BUILD_SLOW_IRQ(14); -BUILD_SLOW_IRQ(15); -BUILD_SLOW_IRQ(16); -BUILD_SLOW_IRQ(17); -BUILD_SLOW_IRQ(18); -BUILD_SLOW_IRQ(19); -BUILD_SLOW_IRQ(20); -BUILD_SLOW_IRQ(21); -BUILD_SLOW_IRQ(22); -BUILD_SLOW_IRQ(23); -BUILD_SLOW_IRQ(24); -BUILD_SLOW_IRQ(25); -BUILD_SLOW_IRQ(26); -BUILD_SLOW_IRQ(27); -BUILD_SLOW_IRQ(28); -BUILD_SLOW_IRQ(29); -BUILD_SLOW_IRQ(30); -BUILD_SLOW_IRQ(31); - -asm_irq_handler slow_handlers[32] = { - [0] = atari_slow_irq_0_handler, - [1] = atari_slow_irq_1_handler, - [2] = atari_slow_irq_2_handler, - [3] = atari_slow_irq_3_handler, - [4] = atari_slow_irq_4_handler, - [5] = atari_slow_irq_5_handler, - [6] = atari_slow_irq_6_handler, - [7] = atari_slow_irq_7_handler, - [8] = atari_slow_irq_8_handler, - [9] = atari_slow_irq_9_handler, - [10] = atari_slow_irq_10_handler, - [11] = atari_slow_irq_11_handler, - [12] = atari_slow_irq_12_handler, - [13] = atari_slow_irq_13_handler, - [14] = atari_slow_irq_14_handler, - [15] = atari_slow_irq_15_handler, - [16] = atari_slow_irq_16_handler, - [17] = atari_slow_irq_17_handler, - [18] = atari_slow_irq_18_handler, - [19] = atari_slow_irq_19_handler, - [20] = atari_slow_irq_20_handler, - [21] = atari_slow_irq_21_handler, - [22] = atari_slow_irq_22_handler, - [23] = atari_slow_irq_23_handler, - [24] = atari_slow_irq_24_handler, - [25] = atari_slow_irq_25_handler, - [26] = atari_slow_irq_26_handler, - [27] = atari_slow_irq_27_handler, - [28] = atari_slow_irq_28_handler, - [29] = atari_slow_irq_29_handler, - [30] = atari_slow_irq_30_handler, - [31] = atari_slow_irq_31_handler -}; - -asmlinkage void atari_fast_irq_handler( void ); -asmlinkage void atari_prio_irq_handler( void ); - -/* Dummy function to allow asm with operands. */ -void atari_fast_prio_irq_dummy (void) { -__asm__ (__ALIGN_STR "\n" -"atari_fast_irq_handler:\n\t" - "orw #0x700,%%sr\n" /* disable all interrupts */ -"atari_prio_irq_handler:\n\t" - "addl %3,%2\n\t" /* preempt_count() += HARDIRQ_OFFSET */ - SAVE_ALL_INT "\n\t" - GET_CURRENT(%%d0) "\n\t" - /* get vector number from stack frame and convert to source */ - "bfextu %%sp@(%c1){#4,#10},%%d0\n\t" - "subw #(0x40-8),%%d0\n\t" - "jpl 1f\n\t" - "addw #(0x40-8-0x18),%%d0\n" - "1:\tlea %a0,%%a0\n\t" - "addql #1,%%a0@(%%d0:l:4)\n\t" - "lea irq_handler,%%a0\n\t" - "lea %%a0@(%%d0:l:8),%%a0\n\t" - "pea %%sp@\n\t" /* push frame address */ - "movel %%a0@(4),%%sp@-\n\t" /* push handler data */ - "movel %%d0,%%sp@-\n\t" /* push int number */ - "movel %%a0@,%%a0\n\t" - "jsr %%a0@\n\t" /* and call the handler */ - "addql #8,%%sp\n\t" - "addql #4,%%sp\n\t" - "jbra ret_from_interrupt" - : : "i" (&kstat_cpu(0).irqs), "n" (PT_OFF_FORMATVEC), - "m" (preempt_count()), "di" (HARDIRQ_OFFSET) -); - for (;;); -} -#endif - /* * Bitmap for free interrupt vector numbers * (new vectors starting from 0x70 can be allocated by -- cgit v1.2.3-59-g8ed1b