Merge branch 'torvalds/master'

[firefly-linux-kernel-4.4.55.git] / arch / m68k / coldfire / intc.c

diff --git a/arch/m68k/coldfire/intc.c b/arch/m68k/coldfire/intc.c
new file mode 100644 (file)
index 0000000..cce2574
--- /dev/null
+++ b/arch/m68k/coldfire/intc.c
@@ -0,0 +1,150 @@
+/*
+ * 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 independent methods to access the
+ * IMR register.
+ */
+#ifdef MCFSIM_IMR_IS_16BITS
+
+void mcf_setimr(int index)
+{
+       u16 imr;
+       imr = __raw_readw(MCFSIM_IMR);
+       __raw_writew(imr | (0x1 << index), MCFSIM_IMR);
+}
+
+void mcf_clrimr(int index)
+{
+       u16 imr;
+       imr = __raw_readw(MCFSIM_IMR);
+       __raw_writew(imr & ~(0x1 << index), MCFSIM_IMR);
+}
+
+void mcf_maskimr(unsigned int mask)
+{
+       u16 imr;
+       imr = __raw_readw(MCFSIM_IMR);
+       imr |= mask;
+       __raw_writew(imr, MCFSIM_IMR);
+}
+
+#else
+
+void mcf_setimr(int index)
+{
+       u32 imr;
+       imr = __raw_readl(MCFSIM_IMR);
+       __raw_writel(imr | (0x1 << index), MCFSIM_IMR);
+}
+
+void mcf_clrimr(int index)
+{
+       u32 imr;
+       imr = __raw_readl(MCFSIM_IMR);
+       __raw_writel(imr & ~(0x1 << index), MCFSIM_IMR);
+}
+
+void mcf_maskimr(unsigned int mask)
+{
+       u32 imr;
+       imr = __raw_readl(MCFSIM_IMR);
+       imr |= mask;
+       __raw_writel(imr, 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(MCFSIM_AVR);
+               avec |= (0x1 << (irq - EIRQ1 + 1));
+               __raw_writeb(avec, MCFSIM_AVR);
+       }
+#endif
+}
+
+static void intc_irq_mask(struct irq_data *d)
+{
+       if (mcf_irq2imr[d->irq])
+               mcf_setimr(mcf_irq2imr[d->irq]);
+}
+
+static void intc_irq_unmask(struct irq_data *d)
+{
+       if (mcf_irq2imr[d->irq])
+               mcf_clrimr(mcf_irq2imr[d->irq]);
+}
+
+static int intc_irq_set_type(struct irq_data *d, unsigned int type)
+{
+       return 0;
+}
+
+static struct irq_chip intc_irq_chip = {
+       .name           = "CF-INTC",
+       .irq_mask       = intc_irq_mask,
+       .irq_unmask     = intc_irq_unmask,
+       .irq_set_type   = intc_irq_set_type,
+};
+
+void __init init_IRQ(void)
+{
+       int irq;
+
+       mcf_maskimr(0xffffffff);
+
+       for (irq = 0; (irq < NR_IRQS); irq++) {
+               irq_set_chip(irq, &intc_irq_chip);
+               irq_set_irq_type(irq, IRQ_TYPE_LEVEL_HIGH);
+               irq_set_handler(irq, handle_level_irq);
+       }
+}
+