--- /dev/null
+/*
+ * (C) Copyright 2000-2002
+ * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+ *
+ * (C) Copyright 2004, Psyent Corporation <www.psyent.com>
+ * Scott McNutt <smcnutt@psyent.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+
+#include <nios2.h>
+#include <nios2-io.h>
+#include <asm/types.h>
+#include <asm/io.h>
+#include <asm/ptrace.h>
+#include <common.h>
+#include <command.h>
+#include <watchdog.h>
+#ifdef CONFIG_STATUS_LED
+#include <status_led.h>
+#endif
+
+#if defined(CONFIG_SYS_NIOS_TMRBASE) && !defined(CONFIG_SYS_NIOS_TMRIRQ)
+#error CONFIG_SYS_NIOS_TMRIRQ not defined (see documentation)
+#endif
+
+/****************************************************************************/
+
+struct irq_action {
+ interrupt_handler_t *handler;
+ void *arg;
+ int count;
+};
+
+static struct irq_action vecs[32];
+
+/*************************************************************************/
+volatile ulong timestamp = 0;
+
+void reset_timer (void)
+{
+ nios_timer_t *tmr =(nios_timer_t *)CONFIG_SYS_NIOS_TMRBASE;
+
+ /* From Embedded Peripherals Handbook:
+ *
+ * "When the hardware is configured with Writeable period
+ * disabled, writing to one of the period_n registers causes
+ * the counter to reset to the fixed Timeout Period specified
+ * at system generation time."
+ *
+ * Here we force a reload to prevent early timeouts from
+ * get_timer() when the interrupt period is greater than
+ * than 1 msec.
+ *
+ * Simply write to periodl with its own value to force an
+ * internal counter reload, THEN reset the timestamp.
+ */
+ writel (readl (&tmr->periodl), &tmr->periodl);
+ timestamp = 0;
+
+ /* From Embedded Peripherals Handbook:
+ *
+ * "Writing to one of the period_n registers stops the internal
+ * counter, except when the hardware is configured with Start/Stop
+ * control bits off. If Start/Stop control bits is off, writing
+ * either register does not stop the counter."
+ *
+ * In order to accomodate either configuration, the control
+ * register is re-written. If the counter is stopped, it will
+ * be restarted. If it is running, the write is essentially
+ * a nop.
+ */
+ writel (NIOS_TIMER_ITO | NIOS_TIMER_CONT | NIOS_TIMER_START,
+ &tmr->control);
+
+}
+
+ulong get_timer (ulong base)
+{
+ WATCHDOG_RESET ();
+ return (timestamp - base);
+}
+
+/*
+ * This function is derived from Blackfin code (read timebase as long long).
+ * On Nios2 it just returns the timer value.
+ */
+unsigned long long get_ticks(void)
+{
+ return get_timer(0);
+}
+
+/*
+ * This function is derived from Blackfin code.
+ * On Nios2 it returns the number of timer ticks per second.
+ */
+ulong get_tbclk(void)
+{
+ ulong tbclk;
+
+ tbclk = CONFIG_SYS_HZ;
+ return tbclk;
+}
+
+/* The board must handle this interrupt if a timer is not
+ * provided.
+ */
+#if defined(CONFIG_SYS_NIOS_TMRBASE)
+void tmr_isr (void *arg)
+{
+ nios_timer_t *tmr = (nios_timer_t *)arg;
+ /* Interrupt is cleared by writing anything to the
+ * status register.
+ */
+ writel (0, &tmr->status);
+ timestamp += CONFIG_SYS_NIOS_TMRMS;
+#ifdef CONFIG_STATUS_LED
+ status_led_tick(timestamp);
+#endif
+}
+
+static void tmr_init (void)
+{
+ nios_timer_t *tmr =(nios_timer_t *)CONFIG_SYS_NIOS_TMRBASE;
+
+ writel (0, &tmr->status);
+ writel (0, &tmr->control);
+ writel (NIOS_TIMER_STOP, &tmr->control);
+
+#if defined(CONFIG_SYS_NIOS_TMRCNT)
+ writel (CONFIG_SYS_NIOS_TMRCNT & 0xffff, &tmr->periodl);
+ writel ((CONFIG_SYS_NIOS_TMRCNT >> 16) & 0xffff, &tmr->periodh);
+#endif
+ writel (NIOS_TIMER_ITO | NIOS_TIMER_CONT | NIOS_TIMER_START,
+ &tmr->control);
+ irq_install_handler (CONFIG_SYS_NIOS_TMRIRQ, tmr_isr, (void *)tmr);
+}
+
+#endif /* CONFIG_SYS_NIOS_TMRBASE */
+
+/*************************************************************************/
+int disable_interrupts (void)
+{
+ int val = rdctl (CTL_STATUS);
+ wrctl (CTL_STATUS, val & ~STATUS_IE);
+ return (val & STATUS_IE);
+}
+
+void enable_interrupts( void )
+{
+ int val = rdctl (CTL_STATUS);
+ wrctl (CTL_STATUS, val | STATUS_IE);
+}
+
+void external_interrupt (struct pt_regs *regs)
+{
+ unsigned irqs;
+ struct irq_action *act;
+
+ /* Evaluate only irqs that are both enabled AND pending */
+ irqs = rdctl (CTL_IENABLE) & rdctl (CTL_IPENDING);
+ act = vecs;
+
+ /* Assume (as does the Nios2 HAL) that bit 0 is highest
+ * priority. NOTE: There is ALWAYS a handler assigned
+ * (the default if no other).
+ */
+ while (irqs) {
+ if (irqs & 1) {
+ act->handler (act->arg);
+ act->count++;
+ }
+ irqs >>=1;
+ act++;
+ }
+}
+
+static void def_hdlr (void *arg)
+{
+ unsigned irqs = rdctl (CTL_IENABLE);
+
+ /* Disable the individual interrupt -- with gratuitous
+ * warning.
+ */
+ irqs &= ~(1 << (int)arg);
+ wrctl (CTL_IENABLE, irqs);
+ printf ("WARNING: Disabling unhandled interrupt: %d\n",
+ (int)arg);
+}
+
+/*************************************************************************/
+void irq_install_handler (int irq, interrupt_handler_t *hdlr, void *arg)
+{
+
+ int flag;
+ struct irq_action *act;
+ unsigned ena = rdctl (CTL_IENABLE);
+
+ if ((irq < 0) || (irq > 31))
+ return;
+ act = &vecs[irq];
+
+ flag = disable_interrupts ();
+ if (hdlr) {
+ act->handler = hdlr;
+ act->arg = arg;
+ ena |= (1 << irq); /* enable */
+ } else {
+ act->handler = def_hdlr;
+ act->arg = (void *)irq;
+ ena &= ~(1 << irq); /* disable */
+ }
+ wrctl (CTL_IENABLE, ena);
+ if (flag) enable_interrupts ();
+}
+
+
+int interrupt_init (void)
+{
+ int i;
+
+ /* Assign the default handler to all */
+ for (i = 0; i < 32; i++) {
+ vecs[i].handler = def_hdlr;
+ vecs[i].arg = (void *)i;
+ vecs[i].count = 0;
+ }
+
+#if defined(CONFIG_SYS_NIOS_TMRBASE)
+ tmr_init ();
+#endif
+
+ enable_interrupts ();
+ return (0);
+}
+
+
+/*************************************************************************/
+#if defined(CONFIG_CMD_IRQ)
+int do_irqinfo (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
+{
+ int i;
+ struct irq_action *act = vecs;
+
+ printf ("\nInterrupt-Information:\n\n");
+ printf ("Nr Routine Arg Count\n");
+ printf ("-----------------------------\n");
+
+ for (i=0; i<32; i++) {
+ if (act->handler != def_hdlr) {
+ printf ("%02d %08lx %08lx %d\n",
+ i,
+ (ulong)act->handler,
+ (ulong)act->arg,
+ act->count);
+ }
+ act++;
+ }
+ printf ("\n");
+
+ return (0);
+}
+#endif
Code Review / kvmfornfv.git / blobdiff