m68k/atari: use dedicated irq_chip for timer D interrupts

Add a special irq_chip for the Atari MFP timer D interrupt,
which is used as a polling timer for EtherNEC and NetUSBee

Signed-off-by: Michael Schmitz <schmitz@debian.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

diff --git a/arch/m68k/atari/ataints.c b/arch/m68k/atari/ataints.c
index 3f41092..f699c82 100644 (file)
--- a/arch/m68k/atari/ataints.c
+++ b/arch/m68k/atari/ataints.c
@@ -122,6 +122,62 @@ static struct irq_chip atari_irq_chip = {
 };
 
 /*
+ * ST-MFP timer D chained interrupts - each driver gets its own timer
+ * interrupt instance.
+ */
+
+struct mfptimerbase {
+       volatile struct MFP *mfp;
+       unsigned char mfp_mask, mfp_data;
+       unsigned short int_mask;
+       int handler_irq, mfptimer_irq, server_irq;
+       char *name;
+} stmfp_base = {
+       .mfp            = &st_mfp,
+       .int_mask       = 0x0,
+       .handler_irq    = IRQ_MFP_TIMD,
+       .mfptimer_irq   = IRQ_MFP_TIMER1,
+       .name           = "MFP Timer D"
+};
+
+static irqreturn_t mfptimer_handler(int irq, void *dev_id)
+{
+       struct mfptimerbase *base = dev_id;
+       int mach_irq;
+       unsigned char ints;
+
+       mach_irq = base->mfptimer_irq;
+       ints = base->int_mask;
+       for (; ints; mach_irq++, ints >>= 1) {
+               if (ints & 1)
+                       generic_handle_irq(mach_irq);
+       }
+       return IRQ_HANDLED;
+}
+
+
+static void atari_mfptimer_enable(struct irq_data *data)
+{
+       int mfp_num = data->irq - IRQ_MFP_TIMER1;
+       stmfp_base.int_mask |= 1 << mfp_num;
+       atari_enable_irq(IRQ_MFP_TIMD);
+}
+
+static void atari_mfptimer_disable(struct irq_data *data)
+{
+       int mfp_num = data->irq - IRQ_MFP_TIMER1;
+       stmfp_base.int_mask &= ~(1 << mfp_num);
+       if (!stmfp_base.int_mask)
+               atari_disable_irq(IRQ_MFP_TIMD);
+}
+
+static struct irq_chip atari_mfptimer_chip = {
+       .name           = "timer_d",
+       .irq_enable     = atari_mfptimer_enable,
+       .irq_disable    = atari_mfptimer_disable,
+};
+
+/*
  * void atari_init_IRQ (void)
  *
  * Parameters: None
@@ -198,6 +254,20 @@ void __init atari_init_IRQ(void)
        /* Initialize the PSG: all sounds off, both ports output */
        sound_ym.rd_data_reg_sel = 7;
        sound_ym.wd_data = 0xff;
+
+       m68k_setup_irq_controller(&atari_mfptimer_chip, handle_simple_irq,
+                                 IRQ_MFP_TIMER1, 8);
+
+       /* prepare timer D data for use as poll interrupt */
+       /* set Timer D data Register - needs to be > 0 */
+       st_mfp.tim_dt_d = 254;  /* < 100 Hz */
+       /* start timer D, div = 1:100 */
+       st_mfp.tim_ct_cd = (st_mfp.tim_ct_cd & 0xf0) | 0x6;
+
+       /* request timer D dispatch handler */
+       if (request_irq(IRQ_MFP_TIMD, mfptimer_handler, IRQF_SHARED,
+                       stmfp_base.name, &stmfp_base))
+               pr_err("Couldn't register %s interrupt\n", stmfp_base.name);
 }
 
 

diff --git a/arch/m68k/include/asm/atariints.h b/arch/m68k/include/asm/atariints.h
index 5fc13bd..8f71504 100644 (file)
--- a/arch/m68k/include/asm/atariints.h
+++ b/arch/m68k/include/asm/atariints.h
@@ -94,6 +94,15 @@
 #define IRQ_SCCA_RX         (52)
 #define IRQ_SCCA_SPCOND             (54)
 
+/* shared MFP timer D interrupts - hires timer for EtherNEC et al. */
+#define IRQ_MFP_TIMER1       (64)
+#define IRQ_MFP_TIMER2       (65)
+#define IRQ_MFP_TIMER3       (66)
+#define IRQ_MFP_TIMER4       (67)
+#define IRQ_MFP_TIMER5       (68)
+#define IRQ_MFP_TIMER6       (69)
+#define IRQ_MFP_TIMER7       (70)
+#define IRQ_MFP_TIMER8       (71)
 
 #define INT_CLK   24576            /* CLK while int_clk =2.456MHz and divide = 100 */
 #define INT_TICKS 246      /* to make sched_time = 99.902... HZ */