diff options
Diffstat (limited to 'arch/ppc/amiga/cia.c')
| -rw-r--r-- | arch/ppc/amiga/cia.c | 178 |
1 files changed, 178 insertions, 0 deletions
diff --git a/arch/ppc/amiga/cia.c b/arch/ppc/amiga/cia.c new file mode 100644 index 000000000000..ad961465b6cb --- /dev/null +++ b/arch/ppc/amiga/cia.c @@ -0,0 +1,178 @@ +/* + * arch/ppc/amiga/cia.c - CIA support + * + * Copyright (C) 1996 Roman Zippel + * + * The concept of some functions bases on the original Amiga OS function + * + * 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/sched.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/kernel_stat.h> +#include <linux/init.h> + +#include <asm/irq.h> +#include <asm/amigahw.h> +#include <asm/amigaints.h> + +struct ciabase { + volatile struct CIA *cia; + u_char icr_mask, icr_data; + u_short int_mask; + int handler_irq, cia_irq, server_irq; + char *name; +} ciaa_base = { + &ciaa, 0, 0, IF_PORTS, + IRQ_AMIGA_AUTO_2, IRQ_AMIGA_CIAA, + IRQ_AMIGA_PORTS, + "CIAA handler" +}, ciab_base = { + &ciab, 0, 0, IF_EXTER, + IRQ_AMIGA_AUTO_6, IRQ_AMIGA_CIAB, + IRQ_AMIGA_EXTER, + "CIAB handler" +}; + +#define CIA_SET_BASE_ADJUST_IRQ(base, irq) \ +do { \ + if (irq >= IRQ_AMIGA_CIAB) { \ + base = &ciab_base; \ + irq -= IRQ_AMIGA_CIAB; \ + } else { \ + base = &ciaa_base; \ + irq -= IRQ_AMIGA_CIAA; \ + } \ +} while (0) + +/* + * Cause or clear CIA interrupts, return old interrupt status. + */ + +static unsigned char cia_set_irq_private(struct ciabase *base, + unsigned char mask) +{ + u_char old; + + old = (base->icr_data |= base->cia->icr); + if (mask & CIA_ICR_SETCLR) + base->icr_data |= mask; + else + base->icr_data &= ~mask; + if (base->icr_data & base->icr_mask) + custom.intreq = IF_SETCLR | base->int_mask; + return old & base->icr_mask; +} + +unsigned char cia_set_irq(unsigned int irq, int set) +{ + struct ciabase *base; + unsigned char mask; + + if (irq >= IRQ_AMIGA_CIAB) + mask = (1 << (irq - IRQ_AMIGA_CIAB)); + else + mask = (1 << (irq - IRQ_AMIGA_CIAA)); + mask |= (set) ? CIA_ICR_SETCLR : 0; + + CIA_SET_BASE_ADJUST_IRQ(base, irq); + + return cia_set_irq_private(base, mask); +} + +unsigned char cia_get_irq_mask(unsigned int irq) +{ + struct ciabase *base; + + CIA_SET_BASE_ADJUST_IRQ(base, irq); + + return base->cia->icr; +} + +/* + * Enable or disable CIA interrupts, return old interrupt mask. + */ + +static unsigned char cia_able_irq_private(struct ciabase *base, + unsigned char mask) +{ + u_char old; + + old = base->icr_mask; + base->icr_data |= base->cia->icr; + base->cia->icr = mask; + if (mask & CIA_ICR_SETCLR) + base->icr_mask |= mask; + else + base->icr_mask &= ~mask; + base->icr_mask &= CIA_ICR_ALL; + + if (base->icr_data & base->icr_mask) + custom.intreq = IF_SETCLR | base->int_mask; + return old; +} + +unsigned char cia_able_irq(unsigned int irq, int enable) +{ + struct ciabase *base; + unsigned char mask; + + if (irq >= IRQ_AMIGA_CIAB) + mask = (1 << (irq - IRQ_AMIGA_CIAB)); + else + mask = (1 << (irq - IRQ_AMIGA_CIAA)); + mask |= (enable) ? CIA_ICR_SETCLR : 0; + + CIA_SET_BASE_ADJUST_IRQ(base, irq); + + return cia_able_irq_private(base, mask); +} + +static void cia_handler(int irq, void *dev_id, struct pt_regs *fp) +{ + struct ciabase *base = (struct ciabase *)dev_id; + irq_desc_t *desc; + struct irqaction *action; + int i; + unsigned char ints; + + irq = base->cia_irq; + desc = irq_desc + irq; + ints = cia_set_irq_private(base, CIA_ICR_ALL); + custom.intreq = base->int_mask; + for (i = 0; i < CIA_IRQS; i++, irq++) { + if (ints & 1) { + kstat_cpu(0).irqs[irq]++; + action = desc->action; + action->handler(irq, action->dev_id, fp); + } + ints >>= 1; + desc++; + } + amiga_do_irq_list(base->server_irq, fp); +} + +void __init cia_init_IRQ(struct ciabase *base) +{ + extern struct irqaction amiga_sys_irqaction[AUTO_IRQS]; + struct irqaction *action; + + /* clear any pending interrupt and turn off all interrupts */ + cia_set_irq_private(base, CIA_ICR_ALL); + cia_able_irq_private(base, CIA_ICR_ALL); + + /* install CIA handler */ + action = &amiga_sys_irqaction[base->handler_irq-IRQ_AMIGA_AUTO]; + action->handler = cia_handler; + action->dev_id = base; + action->name = base->name; + setup_irq(base->handler_irq, &amiga_sys_irqaction[base->handler_irq-IRQ_AMIGA_AUTO]); + + custom.intena = IF_SETCLR | base->int_mask; +} |