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195 lines
4.5 KiB
195 lines
4.5 KiB
/* |
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* linux/arch/m68k/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/errno.h> |
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#include <linux/kernel_stat.h> |
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#include <linux/init.h> |
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#include <linux/seq_file.h> |
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#include <linux/interrupt.h> |
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#include <linux/irq.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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unsigned char icr_mask, icr_data; |
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unsigned 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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.cia = &ciaa, |
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.int_mask = IF_PORTS, |
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.handler_irq = IRQ_AMIGA_PORTS, |
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.cia_irq = IRQ_AMIGA_CIAA, |
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.name = "CIAA" |
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}, ciab_base = { |
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.cia = &ciab, |
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.int_mask = IF_EXTER, |
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.handler_irq = IRQ_AMIGA_EXTER, |
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.cia_irq = IRQ_AMIGA_CIAB, |
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.name = "CIAB" |
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}; |
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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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unsigned char cia_set_irq(struct ciabase *base, unsigned char mask) |
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{ |
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unsigned 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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amiga_custom.intreq = IF_SETCLR | base->int_mask; |
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return old & base->icr_mask; |
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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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unsigned char cia_able_irq(struct ciabase *base, unsigned char mask) |
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{ |
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unsigned 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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amiga_custom.intreq = IF_SETCLR | base->int_mask; |
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return old; |
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} |
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static irqreturn_t cia_handler(int irq, void *dev_id) |
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{ |
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struct ciabase *base = dev_id; |
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int mach_irq; |
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unsigned char ints; |
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unsigned long flags; |
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/* Interrupts get disabled while the timer irq flag is cleared and |
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* the timer interrupt serviced. |
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*/ |
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mach_irq = base->cia_irq; |
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local_irq_save(flags); |
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ints = cia_set_irq(base, CIA_ICR_ALL); |
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amiga_custom.intreq = base->int_mask; |
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if (ints & 1) |
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generic_handle_irq(mach_irq); |
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local_irq_restore(flags); |
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mach_irq++, ints >>= 1; |
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for (; ints; mach_irq++, ints >>= 1) { |
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if (ints & 1) |
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generic_handle_irq(mach_irq); |
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} |
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return IRQ_HANDLED; |
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} |
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static void cia_irq_enable(struct irq_data *data) |
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{ |
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unsigned int irq = data->irq; |
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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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cia_set_irq(&ciab_base, mask); |
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cia_able_irq(&ciab_base, CIA_ICR_SETCLR | mask); |
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} else { |
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mask = 1 << (irq - IRQ_AMIGA_CIAA); |
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cia_set_irq(&ciaa_base, mask); |
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cia_able_irq(&ciaa_base, CIA_ICR_SETCLR | mask); |
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} |
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} |
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static void cia_irq_disable(struct irq_data *data) |
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{ |
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unsigned int irq = data->irq; |
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if (irq >= IRQ_AMIGA_CIAB) |
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cia_able_irq(&ciab_base, 1 << (irq - IRQ_AMIGA_CIAB)); |
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else |
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cia_able_irq(&ciaa_base, 1 << (irq - IRQ_AMIGA_CIAA)); |
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} |
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static struct irq_chip cia_irq_chip = { |
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.name = "cia", |
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.irq_enable = cia_irq_enable, |
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.irq_disable = cia_irq_disable, |
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}; |
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/* |
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* Override auto irq 2 & 6 and use them as general chain |
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* for external interrupts, we link the CIA interrupt sources |
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* into this chain. |
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*/ |
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static void auto_irq_enable(struct irq_data *data) |
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{ |
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switch (data->irq) { |
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case IRQ_AUTO_2: |
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amiga_custom.intena = IF_SETCLR | IF_PORTS; |
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break; |
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case IRQ_AUTO_6: |
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amiga_custom.intena = IF_SETCLR | IF_EXTER; |
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break; |
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} |
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} |
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static void auto_irq_disable(struct irq_data *data) |
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{ |
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switch (data->irq) { |
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case IRQ_AUTO_2: |
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amiga_custom.intena = IF_PORTS; |
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break; |
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case IRQ_AUTO_6: |
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amiga_custom.intena = IF_EXTER; |
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break; |
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} |
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} |
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static struct irq_chip auto_irq_chip = { |
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.name = "auto", |
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.irq_enable = auto_irq_enable, |
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.irq_disable = auto_irq_disable, |
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}; |
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void __init cia_init_IRQ(struct ciabase *base) |
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{ |
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m68k_setup_irq_controller(&cia_irq_chip, handle_simple_irq, |
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base->cia_irq, CIA_IRQS); |
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/* clear any pending interrupt and turn off all interrupts */ |
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cia_set_irq(base, CIA_ICR_ALL); |
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cia_able_irq(base, CIA_ICR_ALL); |
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/* override auto int and install CIA handler */ |
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m68k_setup_irq_controller(&auto_irq_chip, handle_simple_irq, |
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base->handler_irq, 1); |
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m68k_irq_startup_irq(base->handler_irq); |
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if (request_irq(base->handler_irq, cia_handler, IRQF_SHARED, |
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base->name, base)) |
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pr_err("Couldn't register %s interrupt\n", base->name); |
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}
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