waterDataPreprocessing commandProcessing.c 李欣儒 commit at 2021-03-22

waterDataPreprocessing/externalListeningThread/commandProcessing.c

@@ -230,3 +230,194 @@ static void u300_set_mode(enum clock_event_mode mode,
 		 * The actual event will be programmed by the next event hook,
 		 * so we just set a dummy value somewhere at the end of the
 		 * universe here.
+		 */
+		/* Disable interrupts on GPT1 */
+		writel(U300_TIMER_APP_GPT1IE_IRQ_DISABLE,
+		       U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT1IE);
+		/* Disable GP1 while we're reprogramming it. */
+		writel(U300_TIMER_APP_DGPT1_TIMER_DISABLE,
+		       U300_TIMER_APP_VBASE + U300_TIMER_APP_DGPT1);
+		/*
+		 * Expire far in the future, u300_set_next_event() will be
+		 * called soon...
+		 */
+		writel(0xFFFFFFFF, U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT1TC);
+		/* We run one shot per tick here! */
+		writel(U300_TIMER_APP_SGPT1M_MODE_ONE_SHOT,
+		       U300_TIMER_APP_VBASE + U300_TIMER_APP_SGPT1M);
+		/* Enable interrupts for this timer */
+		writel(U300_TIMER_APP_GPT1IE_IRQ_ENABLE,
+		       U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT1IE);
+		/* Enable timer */
+		writel(U300_TIMER_APP_EGPT1_TIMER_ENABLE,
+		       U300_TIMER_APP_VBASE + U300_TIMER_APP_EGPT1);
+		break;
+	case CLOCK_EVT_MODE_UNUSED:
+	case CLOCK_EVT_MODE_SHUTDOWN:
+		/* Disable interrupts on GP1 */
+		writel(U300_TIMER_APP_GPT1IE_IRQ_DISABLE,
+		       U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT1IE);
+		/* Disable GP1 */
+		writel(U300_TIMER_APP_DGPT1_TIMER_DISABLE,
+		       U300_TIMER_APP_VBASE + U300_TIMER_APP_DGPT1);
+		break;
+	case CLOCK_EVT_MODE_RESUME:
+		/* Ignore this call */
+		break;
+	}
+}
+
+/*
+ * The app timer in one shot mode obviously has to be reprogrammed
+ * in EXACTLY this sequence to work properly. Do NOT try to e.g. replace
+ * the interrupt disable + timer disable commands with a reset command,
+ * it will fail miserably. Apparently (and I found this the hard way)
+ * the timer is very sensitive to the instruction order, though you don't
+ * get that impression from the data sheet.
+ */
+static int u300_set_next_event(unsigned long cycles,
+			       struct clock_event_device *evt)
+
+{
+	/* Disable interrupts on GPT1 */
+	writel(U300_TIMER_APP_GPT1IE_IRQ_DISABLE,
+	       U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT1IE);
+	/* Disable GP1 while we're reprogramming it. */
+	writel(U300_TIMER_APP_DGPT1_TIMER_DISABLE,
+	       U300_TIMER_APP_VBASE + U300_TIMER_APP_DGPT1);
+	/* Reset the General Purpose timer 1. */
+	writel(U300_TIMER_APP_RGPT1_TIMER_RESET,
+	       U300_TIMER_APP_VBASE + U300_TIMER_APP_RGPT1);
+	/* IRQ in n * cycles */
+	writel(cycles, U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT1TC);
+	/*
+	 * We run one shot per tick here! (This is necessary to reconfigure,
+	 * the timer will tilt if you don't!)
+	 */
+	writel(U300_TIMER_APP_SGPT1M_MODE_ONE_SHOT,
+	       U300_TIMER_APP_VBASE + U300_TIMER_APP_SGPT1M);
+	/* Enable timer interrupts */
+	writel(U300_TIMER_APP_GPT1IE_IRQ_ENABLE,
+	       U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT1IE);
+	/* Then enable the OS timer again */
+	writel(U300_TIMER_APP_EGPT1_TIMER_ENABLE,
+	       U300_TIMER_APP_VBASE + U300_TIMER_APP_EGPT1);
+	return 0;
+}
+
+
+/* Use general purpose timer 1 as clock event */
+static struct clock_event_device clockevent_u300_1mhz = {
+	.name		= "GPT1",
+	.rating		= 300, /* Reasonably fast and accurate clock event */
+	.features	= CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
+	.set_next_event	= u300_set_next_event,
+	.set_mode	= u300_set_mode,
+};
+
+/* Clock event timer interrupt handler */
+static irqreturn_t u300_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = &clockevent_u300_1mhz;
+	/* ACK/Clear timer IRQ for the APP GPT1 Timer */
+	writel(U300_TIMER_APP_GPT1IA_IRQ_ACK,
+		U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT1IA);
+	evt->event_handler(evt);
+	return IRQ_HANDLED;
+}
+
+static struct irqaction u300_timer_irq = {
+	.name		= "U300 Timer Tick",
+	.flags		= IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
+	.handler	= u300_timer_interrupt,
+};
+
+/*
+ * Override the global weak sched_clock symbol with this
+ * local implementation which uses the clocksource to get some
+ * better resolution when scheduling the kernel. We accept that
+ * this wraps around for now, since it is just a relative time
+ * stamp. (Inspired by OMAP implementation.)
+ */
+
+static u32 notrace u300_read_sched_clock(void)
+{
+	return readl(U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT2CC);
+}
+
+
+/*
+ * This sets up the system timers, clock source and clock event.
+ */
+static void __init u300_timer_init(void)
+{
+	struct clk *clk;
+	unsigned long rate;
+
+	/* Clock the interrupt controller */
+	clk = clk_get_sys("apptimer", NULL);
+	BUG_ON(IS_ERR(clk));
+	clk_prepare_enable(clk);
+	rate = clk_get_rate(clk);
+
+	setup_sched_clock(u300_read_sched_clock, 32, rate);
+
+	/*
+	 * Disable the "OS" and "DD" timers - these are designed for Symbian!
+	 * Example usage in cnh1601578 cpu subsystem pd_timer_app.c
+	 */
+	writel(U300_TIMER_APP_CRC_CLOCK_REQUEST_ENABLE,
+		U300_TIMER_APP_VBASE + U300_TIMER_APP_CRC);
+	writel(U300_TIMER_APP_ROST_TIMER_RESET,
+		U300_TIMER_APP_VBASE + U300_TIMER_APP_ROST);
+	writel(U300_TIMER_APP_DOST_TIMER_DISABLE,
+		U300_TIMER_APP_VBASE + U300_TIMER_APP_DOST);
+	writel(U300_TIMER_APP_RDDT_TIMER_RESET,
+		U300_TIMER_APP_VBASE + U300_TIMER_APP_RDDT);
+	writel(U300_TIMER_APP_DDDT_TIMER_DISABLE,
+		U300_TIMER_APP_VBASE + U300_TIMER_APP_DDDT);
+
+	/* Reset the General Purpose timer 1. */
+	writel(U300_TIMER_APP_RGPT1_TIMER_RESET,
+		U300_TIMER_APP_VBASE + U300_TIMER_APP_RGPT1);
+
+	/* Set up the IRQ handler */
+	setup_irq(IRQ_U300_TIMER_APP_GP1, &u300_timer_irq);
+
+	/* Reset the General Purpose timer 2 */
+	writel(U300_TIMER_APP_RGPT2_TIMER_RESET,
+		U300_TIMER_APP_VBASE + U300_TIMER_APP_RGPT2);
+	/* Set this timer to run around forever */
+	writel(0xFFFFFFFFU, U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT2TC);
+	/* Set continuous mode so it wraps around */
+	writel(U300_TIMER_APP_SGPT2M_MODE_CONTINUOUS,
+	       U300_TIMER_APP_VBASE + U300_TIMER_APP_SGPT2M);
+	/* Disable timer interrupts */
+	writel(U300_TIMER_APP_GPT2IE_IRQ_DISABLE,
+		U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT2IE);
+	/* Then enable the GP2 timer to use as a free running us counter */
+	writel(U300_TIMER_APP_EGPT2_TIMER_ENABLE,
+		U300_TIMER_APP_VBASE + U300_TIMER_APP_EGPT2);
+
+	/* Use general purpose timer 2 as clock source */
+	if (clocksource_mmio_init(U300_TIMER_APP_VBASE + U300_TIMER_APP_GPT2CC,
+			"GPT2", rate, 300, 32, clocksource_mmio_readl_up))
+		pr_err("timer: failed to initialize U300 clock source\n");
+
+	/* Configure and register the clockevent */
+	clockevents_config_and_register(&clockevent_u300_1mhz, rate,
+					1, 0xffffffff);
+
+	/*
+	 * TODO: init and register the rest of the timers too, they can be
+	 * used by hrtimers!
+	 */
+}
+
+/*
+ * Very simple system timer that only register the clock event and
+ * clock source.
+ */
+struct sys_timer u300_timer = {
+	.init		= u300_timer_init,
+};