![Linus Torvalds](/assets/img/avatar_default.png)
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
179 lines
4 KiB
C
179 lines
4 KiB
C
/*
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* arch/ppc/amiga/cia.c - CIA support
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*
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* Copyright (C) 1996 Roman Zippel
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*
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* The concept of some functions bases on the original Amiga OS function
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*
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* This file is subject to the terms and conditions of the GNU General Public
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* License. See the file COPYING in the main directory of this archive
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* for more details.
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*/
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#include <linux/types.h>
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#include <linux/kernel.h>
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#include <linux/sched.h>
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#include <linux/interrupt.h>
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#include <linux/irq.h>
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#include <linux/kernel_stat.h>
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#include <linux/init.h>
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#include <asm/irq.h>
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#include <asm/amigahw.h>
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#include <asm/amigaints.h>
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struct ciabase {
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volatile struct CIA *cia;
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u_char icr_mask, icr_data;
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u_short int_mask;
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int handler_irq, cia_irq, server_irq;
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char *name;
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} ciaa_base = {
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&ciaa, 0, 0, IF_PORTS,
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IRQ_AMIGA_AUTO_2, IRQ_AMIGA_CIAA,
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IRQ_AMIGA_PORTS,
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"CIAA handler"
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}, ciab_base = {
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&ciab, 0, 0, IF_EXTER,
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IRQ_AMIGA_AUTO_6, IRQ_AMIGA_CIAB,
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IRQ_AMIGA_EXTER,
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"CIAB handler"
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};
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#define CIA_SET_BASE_ADJUST_IRQ(base, irq) \
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do { \
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if (irq >= IRQ_AMIGA_CIAB) { \
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base = &ciab_base; \
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irq -= IRQ_AMIGA_CIAB; \
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} else { \
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base = &ciaa_base; \
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irq -= IRQ_AMIGA_CIAA; \
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} \
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} while (0)
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/*
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* Cause or clear CIA interrupts, return old interrupt status.
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*/
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static unsigned char cia_set_irq_private(struct ciabase *base,
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unsigned char mask)
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{
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u_char old;
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old = (base->icr_data |= base->cia->icr);
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if (mask & CIA_ICR_SETCLR)
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base->icr_data |= mask;
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else
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base->icr_data &= ~mask;
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if (base->icr_data & base->icr_mask)
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custom.intreq = IF_SETCLR | base->int_mask;
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return old & base->icr_mask;
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}
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unsigned char cia_set_irq(unsigned int irq, int set)
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{
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struct ciabase *base;
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unsigned char mask;
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if (irq >= IRQ_AMIGA_CIAB)
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mask = (1 << (irq - IRQ_AMIGA_CIAB));
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else
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mask = (1 << (irq - IRQ_AMIGA_CIAA));
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mask |= (set) ? CIA_ICR_SETCLR : 0;
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CIA_SET_BASE_ADJUST_IRQ(base, irq);
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return cia_set_irq_private(base, mask);
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}
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unsigned char cia_get_irq_mask(unsigned int irq)
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{
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struct ciabase *base;
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CIA_SET_BASE_ADJUST_IRQ(base, irq);
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return base->cia->icr;
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}
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/*
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* Enable or disable CIA interrupts, return old interrupt mask.
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*/
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static unsigned char cia_able_irq_private(struct ciabase *base,
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unsigned char mask)
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{
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u_char old;
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old = base->icr_mask;
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base->icr_data |= base->cia->icr;
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base->cia->icr = mask;
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if (mask & CIA_ICR_SETCLR)
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base->icr_mask |= mask;
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else
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base->icr_mask &= ~mask;
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base->icr_mask &= CIA_ICR_ALL;
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if (base->icr_data & base->icr_mask)
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custom.intreq = IF_SETCLR | base->int_mask;
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return old;
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}
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unsigned char cia_able_irq(unsigned int irq, int enable)
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{
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struct ciabase *base;
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unsigned char mask;
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if (irq >= IRQ_AMIGA_CIAB)
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mask = (1 << (irq - IRQ_AMIGA_CIAB));
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else
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mask = (1 << (irq - IRQ_AMIGA_CIAA));
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mask |= (enable) ? CIA_ICR_SETCLR : 0;
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CIA_SET_BASE_ADJUST_IRQ(base, irq);
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return cia_able_irq_private(base, mask);
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}
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static void cia_handler(int irq, void *dev_id, struct pt_regs *fp)
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{
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struct ciabase *base = (struct ciabase *)dev_id;
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irq_desc_t *desc;
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struct irqaction *action;
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int i;
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unsigned char ints;
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irq = base->cia_irq;
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desc = irq_desc + irq;
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ints = cia_set_irq_private(base, CIA_ICR_ALL);
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custom.intreq = base->int_mask;
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for (i = 0; i < CIA_IRQS; i++, irq++) {
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if (ints & 1) {
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kstat_cpu(0).irqs[irq]++;
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action = desc->action;
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action->handler(irq, action->dev_id, fp);
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}
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ints >>= 1;
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desc++;
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}
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amiga_do_irq_list(base->server_irq, fp);
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}
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void __init cia_init_IRQ(struct ciabase *base)
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{
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extern struct irqaction amiga_sys_irqaction[AUTO_IRQS];
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struct irqaction *action;
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/* clear any pending interrupt and turn off all interrupts */
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cia_set_irq_private(base, CIA_ICR_ALL);
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cia_able_irq_private(base, CIA_ICR_ALL);
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/* install CIA handler */
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action = &amiga_sys_irqaction[base->handler_irq-IRQ_AMIGA_AUTO];
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action->handler = cia_handler;
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action->dev_id = base;
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action->name = base->name;
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setup_irq(base->handler_irq, &amiga_sys_irqaction[base->handler_irq-IRQ_AMIGA_AUTO]);
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custom.intena = IF_SETCLR | base->int_mask;
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}
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