You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
459 lines
14 KiB
459 lines
14 KiB
/*
|
|
* arch/m68k/atari/ataints.c -- Atari Linux interrupt handling code
|
|
*
|
|
* 5/2/94 Roman Hodek:
|
|
* Added support for TT interrupts; setup for TT SCU (may someone has
|
|
* twiddled there and we won't get the right interrupts :-()
|
|
*
|
|
* Major change: The device-independent code in m68k/ints.c didn't know
|
|
* about non-autovec ints yet. It hardcoded the number of possible ints to
|
|
* 7 (IRQ1...IRQ7). But the Atari has lots of non-autovec ints! I made the
|
|
* number of possible ints a constant defined in interrupt.h, which is
|
|
* 47 for the Atari. So we can call request_irq() for all Atari interrupts
|
|
* just the normal way. Additionally, all vectors >= 48 are initialized to
|
|
* call trap() instead of inthandler(). This must be changed here, too.
|
|
*
|
|
* 1995-07-16 Lars Brinkhoff <f93labr@dd.chalmers.se>:
|
|
* Corrected a bug in atari_add_isr() which rejected all SCC
|
|
* interrupt sources if there were no TT MFP!
|
|
*
|
|
* 12/13/95: New interface functions atari_level_triggered_int() and
|
|
* atari_register_vme_int() as support for level triggered VME interrupts.
|
|
*
|
|
* 02/12/96: (Roman)
|
|
* Total rewrite of Atari interrupt handling, for new scheme see comments
|
|
* below.
|
|
*
|
|
* 1996-09-03 lars brinkhoff <f93labr@dd.chalmers.se>:
|
|
* Added new function atari_unregister_vme_int(), and
|
|
* modified atari_register_vme_int() as well as IS_VALID_INTNO()
|
|
* to work with it.
|
|
*
|
|
* This file is subject to the terms and conditions of the GNU General Public
|
|
* License. See the file COPYING in the main directory of this archive
|
|
* for more details.
|
|
*
|
|
*/
|
|
|
|
#include <linux/types.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/kernel_stat.h>
|
|
#include <linux/init.h>
|
|
#include <linux/seq_file.h>
|
|
|
|
#include <asm/system.h>
|
|
#include <asm/traps.h>
|
|
|
|
#include <asm/atarihw.h>
|
|
#include <asm/atariints.h>
|
|
#include <asm/atari_stdma.h>
|
|
#include <asm/irq.h>
|
|
#include <asm/entry.h>
|
|
|
|
|
|
/*
|
|
* Atari interrupt handling scheme:
|
|
* --------------------------------
|
|
*
|
|
* All interrupt source have an internal number (defined in
|
|
* <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 : &mfp.int_mk_a) \
|
|
: (n & 16 ? &tt_mfp.int_mk_b : &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
|
|
* atari_register_vme_int())
|
|
*/
|
|
static int free_vme_vec_bitmap;
|
|
|
|
/* GK:
|
|
* HBL IRQ handler for Falcon. Nobody needs it :-)
|
|
* ++andreas: raise ipl to disable further HBLANK interrupts.
|
|
*/
|
|
asmlinkage void falcon_hblhandler(void);
|
|
asm(".text\n"
|
|
__ALIGN_STR "\n\t"
|
|
"falcon_hblhandler:\n\t"
|
|
"orw #0x200,%sp@\n\t" /* set saved ipl to 2 */
|
|
"rte");
|
|
|
|
extern void atari_microwire_cmd(int cmd);
|
|
|
|
extern int atari_SCC_reset_done;
|
|
|
|
static int atari_startup_irq(unsigned int irq)
|
|
{
|
|
m68k_irq_startup(irq);
|
|
atari_turnon_irq(irq);
|
|
atari_enable_irq(irq);
|
|
return 0;
|
|
}
|
|
|
|
static void atari_shutdown_irq(unsigned int irq)
|
|
{
|
|
atari_disable_irq(irq);
|
|
atari_turnoff_irq(irq);
|
|
m68k_irq_shutdown(irq);
|
|
|
|
if (irq == IRQ_AUTO_4)
|
|
vectors[VEC_INT4] = falcon_hblhandler;
|
|
}
|
|
|
|
static struct irq_controller atari_irq_controller = {
|
|
.name = "atari",
|
|
.lock = __SPIN_LOCK_UNLOCKED(atari_irq_controller.lock),
|
|
.startup = atari_startup_irq,
|
|
.shutdown = atari_shutdown_irq,
|
|
.enable = atari_enable_irq,
|
|
.disable = atari_disable_irq,
|
|
};
|
|
|
|
/*
|
|
* void atari_init_IRQ (void)
|
|
*
|
|
* Parameters: None
|
|
*
|
|
* Returns: Nothing
|
|
*
|
|
* This function should be called during kernel startup to initialize
|
|
* the atari IRQ handling routines.
|
|
*/
|
|
|
|
void __init atari_init_IRQ(void)
|
|
{
|
|
m68k_setup_user_interrupt(VEC_USER, NUM_ATARI_SOURCES - IRQ_USER, NULL);
|
|
m68k_setup_irq_controller(&atari_irq_controller, 1, NUM_ATARI_SOURCES - 1);
|
|
|
|
/* Initialize the MFP(s) */
|
|
|
|
#ifdef ATARI_USE_SOFTWARE_EOI
|
|
mfp.vec_adr = 0x48; /* Software EOI-Mode */
|
|
#else
|
|
mfp.vec_adr = 0x40; /* Automatic EOI-Mode */
|
|
#endif
|
|
mfp.int_en_a = 0x00; /* turn off MFP-Ints */
|
|
mfp.int_en_b = 0x00;
|
|
mfp.int_mk_a = 0xff; /* no Masking */
|
|
mfp.int_mk_b = 0xff;
|
|
|
|
if (ATARIHW_PRESENT(TT_MFP)) {
|
|
#ifdef ATARI_USE_SOFTWARE_EOI
|
|
tt_mfp.vec_adr = 0x58; /* Software EOI-Mode */
|
|
#else
|
|
tt_mfp.vec_adr = 0x50; /* Automatic EOI-Mode */
|
|
#endif
|
|
tt_mfp.int_en_a = 0x00; /* turn off MFP-Ints */
|
|
tt_mfp.int_en_b = 0x00;
|
|
tt_mfp.int_mk_a = 0xff; /* no Masking */
|
|
tt_mfp.int_mk_b = 0xff;
|
|
}
|
|
|
|
if (ATARIHW_PRESENT(SCC) && !atari_SCC_reset_done) {
|
|
scc.cha_a_ctrl = 9;
|
|
MFPDELAY();
|
|
scc.cha_a_ctrl = (char) 0xc0; /* hardware reset */
|
|
}
|
|
|
|
if (ATARIHW_PRESENT(SCU)) {
|
|
/* init the SCU if present */
|
|
tt_scu.sys_mask = 0x10; /* enable VBL (for the cursor) and
|
|
* disable HSYNC interrupts (who
|
|
* needs them?) MFP and SCC are
|
|
* enabled in VME mask
|
|
*/
|
|
tt_scu.vme_mask = 0x60; /* enable MFP and SCC ints */
|
|
} else {
|
|
/* If no SCU and no Hades, the HSYNC interrupt needs to be
|
|
* disabled this way. (Else _inthandler in kernel/sys_call.S
|
|
* gets overruns)
|
|
*/
|
|
|
|
if (!MACH_IS_HADES) {
|
|
vectors[VEC_INT2] = falcon_hblhandler;
|
|
vectors[VEC_INT4] = falcon_hblhandler;
|
|
}
|
|
}
|
|
|
|
if (ATARIHW_PRESENT(PCM_8BIT) && ATARIHW_PRESENT(MICROWIRE)) {
|
|
/* Initialize the LM1992 Sound Controller to enable
|
|
the PSG sound. This is misplaced here, it should
|
|
be in an atasound_init(), that doesn't exist yet. */
|
|
atari_microwire_cmd(MW_LM1992_PSG_HIGH);
|
|
}
|
|
|
|
stdma_init();
|
|
|
|
/* Initialize the PSG: all sounds off, both ports output */
|
|
sound_ym.rd_data_reg_sel = 7;
|
|
sound_ym.wd_data = 0xff;
|
|
}
|
|
|
|
|
|
/*
|
|
* atari_register_vme_int() returns the number of a free interrupt vector for
|
|
* hardware with a programmable int vector (probably a VME board).
|
|
*/
|
|
|
|
unsigned long atari_register_vme_int(void)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < 32; i++)
|
|
if ((free_vme_vec_bitmap & (1 << i)) == 0)
|
|
break;
|
|
|
|
if (i == 16)
|
|
return 0;
|
|
|
|
free_vme_vec_bitmap |= 1 << i;
|
|
return VME_SOURCE_BASE + i;
|
|
}
|
|
|
|
|
|
void atari_unregister_vme_int(unsigned long irq)
|
|
{
|
|
if (irq >= VME_SOURCE_BASE && irq < VME_SOURCE_BASE + VME_MAX_SOURCES) {
|
|
irq -= VME_SOURCE_BASE;
|
|
free_vme_vec_bitmap &= ~(1 << irq);
|
|
}
|
|
}
|
|
|
|
|
|
|