cregit-Linux how code gets into the kernel

Release 4.10 arch/m68k/mac/macints.c

Directory: arch/m68k/mac
/*
 *      Macintosh interrupts
 *
 * General design:
 * In contrary to the Amiga and Atari platforms, the Mac hardware seems to
 * exclusively use the autovector interrupts (the 'generic level0-level7'
 * interrupts with exception vectors 0x19-0x1f). The following interrupt levels
 * are used:
 *      1       - VIA1
 *                - slot 0: one second interrupt (CA2)
 *                - slot 1: VBlank (CA1)
 *                - slot 2: ADB data ready (SR full)
 *                - slot 3: ADB data  (CB2)
 *                - slot 4: ADB clock (CB1)
 *                - slot 5: timer 2
 *                - slot 6: timer 1
 *                - slot 7: status of IRQ; signals 'any enabled int.'
 *
 *      2       - VIA2 or RBV
 *                - slot 0: SCSI DRQ (CA2)
 *                - slot 1: NUBUS IRQ (CA1) need to read port A to find which
 *                - slot 2: /EXP IRQ (only on IIci)
 *                - slot 3: SCSI IRQ (CB2)
 *                - slot 4: ASC IRQ (CB1)
 *                - slot 5: timer 2 (not on IIci)
 *                - slot 6: timer 1 (not on IIci)
 *                - slot 7: status of IRQ; signals 'any enabled int.'
 *
 * Levels 3-6 vary by machine type. For VIA or RBV Macintoshes:
 *
 *      3       - unused (?)
 *
 *      4       - SCC
 *
 *      5       - unused (?)
 *                [serial errors or special conditions seem to raise level 6
 *                interrupts on some models (LC4xx?)]
 *
 *      6       - off switch (?)
 *
 * Machines with Quadra-like VIA hardware, except PSC and PMU machines, support
 * an alternate interrupt mapping, as used by A/UX. It spreads ethernet and
 * sound out to their own autovector IRQs and gives VIA1 a higher priority:
 *
 *      1       - unused (?)
 *
 *      3       - on-board SONIC
 *
 *      5       - Apple Sound Chip (ASC)
 *
 *      6       - VIA1
 *
 * For OSS Macintoshes (IIfx only), we apply an interrupt mapping similar to
 * the Quadra (A/UX) mapping:
 *
 *      1       - ISM IOP (ADB)
 *
 *      2       - SCSI
 *
 *      3       - NuBus
 *
 *      4       - SCC IOP
 *
 *      6       - VIA1
 *
 * For PSC Macintoshes (660AV, 840AV):
 *
 *      3       - PSC level 3
 *                - slot 0: MACE
 *
 *      4       - PSC level 4
 *                - slot 1: SCC channel A interrupt
 *                - slot 2: SCC channel B interrupt
 *                - slot 3: MACE DMA
 *
 *      5       - PSC level 5
 *
 *      6       - PSC level 6
 *
 * Finally we have good 'ole level 7, the non-maskable interrupt:
 *
 *      7       - NMI (programmer's switch on the back of some Macs)
 *                Also RAM parity error on models which support it (IIc, IIfx?)
 *
 * The current interrupt logic looks something like this:
 *
 * - We install dispatchers for the autovector interrupts (1-7). These
 *   dispatchers are responsible for querying the hardware (the
 *   VIA/RBV/OSS/PSC chips) to determine the actual interrupt source. Using
 *   this information a machspec interrupt number is generated by placing the
 *   index of the interrupt hardware into the low three bits and the original
 *   autovector interrupt number in the upper 5 bits. The handlers for the
 *   resulting machspec interrupt are then called.
 *
 * - Nubus is a special case because its interrupts are hidden behind two
 *   layers of hardware. Nubus interrupts come in as index 1 on VIA #2,
 *   which translates to IRQ number 17. In this spot we install _another_
 *   dispatcher. This dispatcher finds the interrupting slot number (9-F) and
 *   then forms a new machspec interrupt number as above with the slot number
 *   minus 9 in the low three bits and the pseudo-level 7 in the upper five
 *   bits.  The handlers for this new machspec interrupt number are then
 *   called. This puts Nubus interrupts into the range 56-62.
 *
 * - The Baboon interrupts (used on some PowerBooks) are an even more special
 *   case. They're hidden behind the Nubus slot $C interrupt thus adding a
 *   third layer of indirection. Why oh why did the Apple engineers do that?
 *
 */

#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/delay.h>

#include <asm/irq.h>
#include <asm/macintosh.h>
#include <asm/macints.h>
#include <asm/mac_via.h>
#include <asm/mac_psc.h>
#include <asm/mac_oss.h>
#include <asm/mac_iop.h>
#include <asm/mac_baboon.h>
#include <asm/hwtest.h>
#include <asm/irq_regs.h>


#define SHUTUP_SONIC

/*
 * console_loglevel determines NMI handler function
 */

irqreturn_t mac_nmi_handler(int, void *);
irqreturn_t mac_debug_handler(int, void *);

/* #define DEBUG_MACINTS */

static unsigned int mac_irq_startup(struct irq_data *);
static void mac_irq_shutdown(struct irq_data *);


static struct irq_chip mac_irq_chip = {
	.name		= "mac",
	.irq_enable	= mac_irq_enable,
	.irq_disable	= mac_irq_disable,
	.irq_startup	= mac_irq_startup,
	.irq_shutdown	= mac_irq_shutdown,
};


void __init mac_init_IRQ(void) { #ifdef DEBUG_MACINTS printk("mac_init_IRQ(): Setting things up...\n"); #endif m68k_setup_irq_controller(&mac_irq_chip, handle_simple_irq, IRQ_USER, NUM_MAC_SOURCES - IRQ_USER); /* Make sure the SONIC interrupt is cleared or things get ugly */ #ifdef SHUTUP_SONIC printk("Killing onboard sonic... "); /* This address should hopefully be mapped already */ if (hwreg_present((void*)(0x50f0a000))) { *(long *)(0x50f0a014) = 0x7fffL; *(long *)(0x50f0a010) = 0L; } printk("Done.\n"); #endif /* SHUTUP_SONIC */ /* * Now register the handlers for the master IRQ handlers * at levels 1-7. Most of the work is done elsewhere. */ if (oss_present) oss_register_interrupts(); else via_register_interrupts(); if (psc) psc_register_interrupts(); if (baboon_present) baboon_register_interrupts(); iop_register_interrupts(); if (request_irq(IRQ_AUTO_7, mac_nmi_handler, 0, "NMI", mac_nmi_handler)) pr_err("Couldn't register NMI\n"); #ifdef DEBUG_MACINTS printk("mac_init_IRQ(): Done!\n"); #endif }

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pre-gitpre-git6443.84%327.27%
linus torvaldslinus torvalds5537.67%19.09%
geert uytterhoevengeert uytterhoeven138.90%545.45%
roman zippelroman zippel138.90%19.09%
al viroal viro10.68%19.09%
Total146100.00%11100.00%

/* * mac_irq_enable - enable an interrupt source * mac_irq_disable - disable an interrupt source * * These routines are just dispatchers to the VIA/OSS/PSC routines. */
void mac_irq_enable(struct irq_data *data) { int irq = data->irq; int irq_src = IRQ_SRC(irq); switch(irq_src) { case 1: case 2: case 7: if (oss_present) oss_irq_enable(irq); else via_irq_enable(irq); break; case 3: case 4: case 5: case 6: if (psc) psc_irq_enable(irq); else if (oss_present) oss_irq_enable(irq); break; case 8: if (baboon_present) baboon_irq_enable(irq); break; } }

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finn thainfinn thain1716.83%337.50%
geert uytterhoevengeert uytterhoeven10.99%112.50%
Total101100.00%8100.00%


void mac_irq_disable(struct irq_data *data) { int irq = data->irq; int irq_src = IRQ_SRC(irq); switch(irq_src) { case 1: case 2: case 7: if (oss_present) oss_irq_disable(irq); else via_irq_disable(irq); break; case 3: case 4: case 5: case 6: if (psc) psc_irq_disable(irq); else if (oss_present) oss_irq_disable(irq); break; case 8: if (baboon_present) baboon_irq_disable(irq); break; } }

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roman zippelroman zippel109.90%111.11%
geert uytterhoevengeert uytterhoeven10.99%111.11%
Total101100.00%9100.00%


static unsigned int mac_irq_startup(struct irq_data *data) { int irq = data->irq; if (IRQ_SRC(irq) == 7 && !oss_present) via_nubus_irq_startup(irq); else mac_irq_enable(data); return 0; }

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static void mac_irq_shutdown(struct irq_data *data) { int irq = data->irq; if (IRQ_SRC(irq) == 7 && !oss_present) via_nubus_irq_shutdown(irq); else mac_irq_disable(data); }

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static int num_debug[8];
irqreturn_t mac_debug_handler(int irq, void *dev_id) { if (num_debug[irq] < 10) { printk("DEBUG: Unexpected IRQ %d\n", irq); num_debug[irq]++; } return IRQ_HANDLED; }

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Total39100.00%2100.00%

static int in_nmi; static volatile int nmi_hold;
irqreturn_t mac_nmi_handler(int irq, void *dev_id) { int i; /* * generate debug output on NMI switch if 'debug' kernel option given * (only works with Penguin!) */ in_nmi++; for (i=0; i<100; i++) udelay(1000); if (in_nmi == 1) { nmi_hold = 1; printk("... pausing, press NMI to resume ..."); } else { printk(" ok!\n"); nmi_hold = 0; } barrier(); while (nmi_hold == 1) udelay(1000); if (console_loglevel >= 8) { #if 0 struct pt_regs *fp = get_irq_regs(); show_state(); printk("PC: %08lx\nSR: %04x SP: %p\n", fp->pc, fp->sr, fp); printk("d0: %08lx d1: %08lx d2: %08lx d3: %08lx\n", fp->d0, fp->d1, fp->d2, fp->d3); printk("d4: %08lx d5: %08lx a0: %08lx a1: %08lx\n", fp->d4, fp->d5, fp->a0, fp->a1); if (STACK_MAGIC != *(unsigned long *)current->kernel_stack_page) printk("Corrupted stack page\n"); printk("Process %s (pid: %d, stackpage=%08lx)\n", current->comm, current->pid, current->kernel_stack_page); if (intr_count == 1) dump_stack((struct frame *)fp); #else /* printk("NMI "); */ #endif } in_nmi--; return IRQ_HANDLED; }

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al viroal viro10.97%112.50%
Total103100.00%8100.00%


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pre-gitpre-git35649.72%520.00%
finn thainfinn thain16022.35%624.00%
roman zippelroman zippel9813.69%14.00%
linus torvaldslinus torvalds628.66%28.00%
geert uytterhoevengeert uytterhoeven365.03%936.00%
al viroal viro40.56%28.00%
Total716100.00%25100.00%
Directory: arch/m68k/mac
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