Home | History | Annotate | Line # | Download | only in isa
isa_milan.c revision 1.5
      1 /*	$NetBSD: isa_milan.c,v 1.5 2002/02/23 20:44:45 leo Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 2001 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Leo Weppelman.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  * 3. All advertising materials mentioning features or use of this software
     19  *    must display the following acknowledgement:
     20  *	This product includes software developed by the NetBSD
     21  *	Foundation, Inc. and its contributors.
     22  * 4. Neither the name of The NetBSD Foundation nor the names of its
     23  *    contributors may be used to endorse or promote products derived
     24  *    from this software without specific prior written permission.
     25  *
     26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     36  * POSSIBILITY OF SUCH DAMAGE.
     37  */
     38 
     39 #include <sys/types.h>
     40 #include <sys/param.h>
     41 #include <sys/systm.h>
     42 #include <sys/device.h>
     43 
     44 #include <dev/isa/isavar.h>
     45 #include <dev/isa/isareg.h>
     46 
     47 #include <machine/iomap.h>
     48 
     49 void	isa_bus_init(void);
     50 
     51 static void new_imask(void);
     52 static void isa_callback(int);
     53 
     54 /*
     55  * Bitmask of currently enabled isa interrupts. Used by new_imask().
     56  */
     57 static u_int16_t imask_enable = 0xffff;
     58 
     59 #define	IRQ_SLAVE		2	/* Slave at level 2		*/
     60 #define MILAN_MAX_ISA_INTS	16	/* Max. number of vectors	*/
     61 #define	ICU_OFFSET		0	/* Interrupt vector base	*/
     62 
     63 #define	WICU(icu, val)		*(volatile u_int8_t*)(icu) = val
     64 
     65 static isa_intr_info_t milan_isa_iinfo[MILAN_MAX_ISA_INTS];
     66 
     67 void
     68 isa_bus_init()
     69 {
     70 	volatile u_int8_t	*icu;
     71 
     72 	/*
     73 	 * Initialize both the icu's:
     74 	 *   - enter Special Mask Mode
     75 	 *   - Block all interrupts
     76 	 */
     77 	icu = (u_int8_t*)(AD_8259_MASTER);
     78 
     79 	icu[0] = 0x11;			/* reset; program device, four bytes */
     80 	icu[1] = ICU_OFFSET;		/* starting at this vector index */
     81 	icu[1] = (1 << IRQ_SLAVE);	/* slave on line 2 */
     82 	icu[1] = 1;			/* 8086 mode */
     83 	icu[1] = 0xff;			/* leave interrupts masked */
     84 	icu[0] = 0x68;			/* special mask mode  */
     85 	icu[0] = 0x0a;			/* Read IRR by default. */
     86 
     87 	icu = (u_int8_t*)(AD_8259_SLAVE);
     88 
     89 	icu[0] = 0x11;			/* reset; program device, four bytes */
     90 	icu[1] = ICU_OFFSET + 8;	/* starting at this vector index */
     91 	icu[1] = IRQ_SLAVE;		/* slave on line 2 */
     92 	icu[1] = 1;			/* 8086 mode */
     93 	icu[1] = 0xff;			/* leave interrupts masked */
     94 	icu[0] = 0x68;			/* special mask mode  */
     95 	icu[0] = 0x0a;			/* Read IRR by default. */
     96 }
     97 
     98 /*
     99  * Determine and activate new interrupt mask by scanning the milan_isa_iinfo
    100  * array for enabled interrupts.
    101  */
    102 static void
    103 new_imask()
    104 {
    105 	int		irq;
    106 	u_int16_t	nmask = 0;
    107 
    108 	for (irq = 0; irq < MILAN_MAX_ISA_INTS; irq++) {
    109 		if (milan_isa_iinfo[irq].ifunc != NULL)
    110 			nmask |= 1 << irq;
    111 		if (nmask >= 0x100)
    112 			nmask |= 1 << IRQ_SLAVE;
    113 	}
    114 	imask_enable = ~nmask;
    115 	WICU(AD_8259_MASTER+1, imask_enable & 0xff);
    116 	WICU(AD_8259_SLAVE+1 , (imask_enable >> 8) & 0xff);
    117 }
    118 
    119 static void
    120 isa_callback(vector)
    121 	int	vector;
    122 {
    123 	isa_intr_info_t	*iinfo_p;
    124 	int		s;
    125 
    126 	iinfo_p = &milan_isa_iinfo[vector];
    127 
    128 	s = splx(iinfo_p->ipl);
    129 	(void) (iinfo_p->ifunc)(iinfo_p->iarg);
    130 	if (vector > 7)
    131 		WICU(AD_8259_SLAVE, 0x60 | (vector & 7));
    132 	else WICU(AD_8259_MASTER, 0x60 | (vector & 7));
    133 	splx(s);
    134 }
    135 
    136 void milan_isa_intr(int, int);
    137 void
    138 milan_isa_intr(vector, sr)
    139 	int	vector, sr;
    140 {
    141 	isa_intr_info_t *iinfo_p;
    142 	int		s;
    143 
    144 	if (vector >= MILAN_MAX_ISA_INTS) {
    145 		printf("milan_isa_intr: Bogus vector %d\n", vector);
    146 		return;
    147 	}
    148 
    149 	/* Ack cascade 0x60 == Specific EOI		*/
    150 	if (vector > 7)
    151 		WICU(AD_8259_MASTER, 0x60|IRQ_SLAVE);
    152 
    153 	iinfo_p = &milan_isa_iinfo[vector];
    154 	if (iinfo_p->ifunc == NULL) {
    155 		printf("milan_isa_intr: Stray interrupt: %d (mask:%04x)\n",
    156 				vector, imask_enable);
    157 		return;
    158 	}
    159 	if ((sr & PSL_IPL) >= (iinfo_p->ipl & PSL_IPL)) {
    160 		/*
    161 		 * We're running at a too high priority now.
    162 		 */
    163 		add_sicallback((si_farg)isa_callback, (void*)vector, 0);
    164 	}
    165 	else {
    166 		s = splx(iinfo_p->ipl);
    167 		(void) (iinfo_p->ifunc)(iinfo_p->iarg);
    168 		if (vector > 7)
    169 			WICU(AD_8259_SLAVE, 0x60 | (vector & 7));
    170 		else WICU(AD_8259_MASTER, 0x60 | (vector & 7));
    171 		splx(s);
    172 	}
    173 }
    174 
    175 /*
    176  * Try to allocate a free interrupt... On the Milan, we have available:
    177  * 5, 9, 10, 11, 13. Or in a bitmask: 0x1720.
    178  */
    179 #define	MILAN_AVAIL_ISA_INTS	0x1720
    180 
    181 int
    182 isa_intr_alloc(ic, mask, type, irq)
    183 	isa_chipset_tag_t ic;
    184 	int mask;
    185 	int type;
    186 	int *irq;
    187 {
    188 	int	i;
    189 
    190 	/*
    191 	 * Say no to impossible questions...
    192 	 */
    193 	if (!(mask &= MILAN_AVAIL_ISA_INTS))
    194 		return 1;
    195 
    196 	for (i = 0; i < MILAN_MAX_ISA_INTS; i++) {
    197 		if (mask & (1<<i)) {
    198 		    if (milan_isa_iinfo[i].ifunc == NULL) {
    199 			*irq = i;
    200 			return 0;
    201 		    }
    202 		}
    203 	}
    204 	return (1);
    205 }
    206 
    207 void *
    208 isa_intr_establish(ic, irq, type, level, ih_fun, ih_arg)
    209 	isa_chipset_tag_t ic;
    210 	int		  irq, type, level;
    211 	int		  (*ih_fun) __P((void *));
    212 	void		  *ih_arg;
    213 {
    214 	isa_intr_info_t *iinfo_p;
    215 
    216 	iinfo_p = &milan_isa_iinfo[irq];
    217 
    218 	if (iinfo_p->ifunc != NULL) {
    219 		printf("isa_intr_establish: interrupt %d was already "
    220 			"established\n", irq);
    221 		return NULL;
    222 	}
    223 
    224 	iinfo_p->slot  = 0;	/* Unused on Milan */
    225 	iinfo_p->ihand = NULL;	/* Unused on Milan */
    226 	iinfo_p->ipl   = level;
    227 	iinfo_p->ifunc = ih_fun;
    228 	iinfo_p->iarg  = ih_arg;
    229 
    230 	new_imask();
    231 	return(iinfo_p);
    232 }
    233 
    234 void
    235 isa_intr_disestablish(ic, handler)
    236 	isa_chipset_tag_t	ic;
    237 	void			*handler;
    238 {
    239 	isa_intr_info_t *iinfo_p = (isa_intr_info_t *)handler;
    240 
    241 	if (iinfo_p->ifunc == NULL)
    242 	    panic("isa_intr_disestablish: interrupt was not established\n");
    243 
    244 	iinfo_p->ifunc = NULL;
    245 	new_imask();
    246 }
    247