[PATCH 13/27] m68k/atari: Remove code and comments about different irq types

From: Geert Uytterhoeven <geert@linux-m68k.org>
To: linux-m68k@vger.kernel.org
Cc: linux-kernel@vger.kernel.org, Greg Ungerer <gerg@uclinux.org>,
	Geert Uytterhoeven <geert@linux-m68k.org>
Subject: [PATCH 13/27] m68k/atari: Remove code and comments about different irq types
Date: Sun, 30 Oct 2011 13:48:21 +0100	[thread overview]
Message-ID: <1319978915-10933-14-git-send-email-geert@linux-m68k.org> (raw)
In-Reply-To: <1319978915-10933-1-git-send-email-geert@linux-m68k.org>

This code was obsoleted during the irq restructuring in 2006.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
---
 arch/m68k/atari/ataints.c |  236 ---------------------------------------------
 1 files changed, 0 insertions(+), 236 deletions(-)

diff --git a/arch/m68k/atari/ataints.c b/arch/m68k/atari/ataints.c
index 6149ff9..af54455 100644
--- a/arch/m68k/atari/ataints.c
+++ b/arch/m68k/atari/ataints.c
@@ -60,244 +60,8 @@
  * <asm/atariints.h>): 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
-- 
1.7.0.4

