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Diffstat (limited to 'arch/m68knommu/platform/coldfire/intc.c')
| -rw-r--r-- | arch/m68knommu/platform/coldfire/intc.c | 153 |
1 files changed, 153 insertions, 0 deletions
diff --git a/arch/m68knommu/platform/coldfire/intc.c b/arch/m68knommu/platform/coldfire/intc.c new file mode 100644 index 000000000000..a4560c86db71 --- /dev/null +++ b/arch/m68knommu/platform/coldfire/intc.c @@ -0,0 +1,153 @@ +/* + * intc.c -- support for the old ColdFire interrupt controller + * + * (C) Copyright 2009, Greg Ungerer <gerg@snapgear.com> + * + * 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/init.h> +#include <linux/kernel.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/io.h> +#include <asm/traps.h> +#include <asm/coldfire.h> +#include <asm/mcfsim.h> + +/* + * The mapping of irq number to a mask register bit is not one-to-one. + * The irq numbers are either based on "level" of interrupt or fixed + * for an autovector-able interrupt. So we keep a local data structure + * that maps from irq to mask register. Not all interrupts will have + * an IMR bit. + */ +unsigned char mcf_irq2imr[NR_IRQS]; + +/* + * Define the miniumun and maximum external interrupt numbers. + * This is also used as the "level" interrupt numbers. + */ +#define EIRQ1 25 +#define EIRQ7 31 + +/* + * In the early version 2 core ColdFire parts the IMR register was 16 bits + * in size. Version 3 (and later version 2) core parts have a 32 bit + * sized IMR register. Provide some size independant methods to access the + * IMR register. + */ +#ifdef MCFSIM_IMR_IS_16BITS + +void mcf_setimr(int index) +{ + u16 imr; + imr = __raw_readw(MCF_MBAR + MCFSIM_IMR); + __raw_writew(imr | (0x1 << index), MCF_MBAR + MCFSIM_IMR); +} + +void mcf_clrimr(int index) +{ + u16 imr; + imr = __raw_readw(MCF_MBAR + MCFSIM_IMR); + __raw_writew(imr & ~(0x1 << index), MCF_MBAR + MCFSIM_IMR); +} + +void mcf_maskimr(unsigned int mask) +{ + u16 imr; + imr = __raw_readw(MCF_MBAR + MCFSIM_IMR); + imr |= mask; + __raw_writew(imr, MCF_MBAR + MCFSIM_IMR); +} + +#else + +void mcf_setimr(int index) +{ + u32 imr; + imr = __raw_readl(MCF_MBAR + MCFSIM_IMR); + __raw_writel(imr | (0x1 << index), MCF_MBAR + MCFSIM_IMR); +} + +void mcf_clrimr(int index) +{ + u32 imr; + imr = __raw_readl(MCF_MBAR + MCFSIM_IMR); + __raw_writel(imr & ~(0x1 << index), MCF_MBAR + MCFSIM_IMR); +} + +void mcf_maskimr(unsigned int mask) +{ + u32 imr; + imr = __raw_readl(MCF_MBAR + MCFSIM_IMR); + imr |= mask; + __raw_writel(imr, MCF_MBAR + MCFSIM_IMR); +} + +#endif + +/* + * Interrupts can be "vectored" on the ColdFire cores that support this old + * interrupt controller. That is, the device raising the interrupt can also + * supply the vector number to interrupt through. The AVR register of the + * interrupt controller enables or disables this for each external interrupt, + * so provide generic support for this. Setting this up is out-of-band for + * the interrupt system API's, and needs to be done by the driver that + * supports this device. Very few devices actually use this. + */ +void mcf_autovector(int irq) +{ +#ifdef MCFSIM_AVR + if ((irq >= EIRQ1) && (irq <= EIRQ7)) { + u8 avec; + avec = __raw_readb(MCF_MBAR + MCFSIM_AVR); + avec |= (0x1 << (irq - EIRQ1 + 1)); + __raw_writeb(avec, MCF_MBAR + MCFSIM_AVR); + } +#endif +} + +static void intc_irq_mask(unsigned int irq) +{ + if (mcf_irq2imr[irq]) + mcf_setimr(mcf_irq2imr[irq]); +} + +static void intc_irq_unmask(unsigned int irq) +{ + if (mcf_irq2imr[irq]) + mcf_clrimr(mcf_irq2imr[irq]); +} + +static int intc_irq_set_type(unsigned int irq, unsigned int type) +{ + return 0; +} + +static struct irq_chip intc_irq_chip = { + .name = "CF-INTC", + .mask = intc_irq_mask, + .unmask = intc_irq_unmask, + .set_type = intc_irq_set_type, +}; + +void __init init_IRQ(void) +{ + int irq; + + init_vectors(); + mcf_maskimr(0xffffffff); + + for (irq = 0; (irq < NR_IRQS); irq++) { + irq_desc[irq].status = IRQ_DISABLED; + irq_desc[irq].action = NULL; + irq_desc[irq].depth = 1; + irq_desc[irq].chip = &intc_irq_chip; + intc_irq_set_type(irq, 0); + } +} + |