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/*
* 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 <linux/module.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().
*/
/*
* 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 unsigned int atari_irq_startup(struct irq_data *data)
{
unsigned int irq = data->irq;
m68k_irq_startup(data);
atari_turnon_irq(irq);
atari_enable_irq(irq);
return 0;
}
static void atari_irq_shutdown(struct irq_data *data)
{
unsigned int irq = data->irq;
atari_disable_irq(irq);
atari_turnoff_irq(irq);
m68k_irq_shutdown(data);
if (irq == IRQ_AUTO_4)
vectors[VEC_INT4] = falcon_hblhandler;
}
static void atari_irq_enable(struct irq_data *data)
{
atari_enable_irq(data->irq);
}
static void atari_irq_disable(struct irq_data *data)
{
atari_disable_irq(data->irq);
}
static struct irq_chip atari_irq_chip = {
.name = "atari",
.irq_startup = atari_irq_startup,
.irq_shutdown = atari_irq_shutdown,
.irq_enable = atari_irq_enable,
.irq_disable = atari_irq_disable,
};
/*
* 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);
m68k_setup_irq_controller(&atari_irq_chip, handle_simple_irq, 1,
NUM_ATARI_SOURCES - 1);
/* Initialize the MFP(s) */
#ifdef ATARI_USE_SOFTWARE_EOI
st_mfp.vec_adr = 0x48; /* Software EOI-Mode */
#else
st_mfp.vec_adr = 0x40; /* Automatic EOI-Mode */
#endif
st_mfp.int_en_a = 0x00; /* turn off MFP-Ints */
st_mfp.int_en_b = 0x00;
st_mfp.int_mk_a = 0xff; /* no Masking */
st_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) {
atari_scc.cha_a_ctrl = 9;
MFPDELAY();
atari_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)
*/
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;
}
EXPORT_SYMBOL(atari_register_vme_int);
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);
}
}
EXPORT_SYMBOL(atari_unregister_vme_int);
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