temperature: add a temperature framework

This commit adds data structures, methods and a process to manage temperature. Currently the only temperature being read is the onewire thermometer, so there is no difference with what we had before. The cost is 1.1 kB in binary size. Well, there is a difference: only the stat engine was reading temperature, while now the thermometer is read continuously (every 15 seconds, or another Kconfig-urable interval). This takes quite some CPU time (18.5ms per polling loop, but allows any user to read temperature (using the API we now provide) without re-reading the onewire bus. The real aim of this is monitoring a board-specific set of sensors, as implemented and show in the next commit. Signed-off-by: Alessandro Rubini <rubini@gnudd.com>

temperature: add a temperature framework
This commit adds data structures, methods and a process to manage temperature. Currently the only temperature being read is the onewire thermometer, so there is no difference with what we had before. The cost is 1.1 kB in binary size. Well, there is a difference: only the stat engine was reading temperature, while now the thermometer is read continuously (every 15 seconds, or another Kconfig-urable interval). This takes quite some CPU time (18.5ms per polling loop, but allows any user to read temperature (using the API we now provide) without re-reading the onewire bus. The real aim of this is monitoring a board-specific set of sensors, as implemented and show in the next commit. Signed-off-by: Alessandro Rubini <rubini@gnudd.com>
e2e7d59a · Alessandro Rubini · 3e630d08 · e2e7d59a · e2e7d59a · e2e7d59a
Commit e2e7d59a authored Feb 19, 2016 by Alessandro Rubini
7 changed files
--- a/Kconfig
+++ b/Kconfig
@@ -26,6 +26,10 @@ config RAMSIZE
 	default 65536 if WR_SWITCH
 	default 131072

+config TEMP_POLL_INTERVAL
+	int
+	default 15
+
 config PLL_VERBOSE
 	boolean
 	default y if WR_SWITCH
@@ -188,6 +192,10 @@ config PRINT_BUFSIZE
 	  also constraints the maximum lenght of text that can be written
 	  in a single call to printf.

+config TEMP_POLL_INTERVAL
+	depends on DEVELOPER && WR_NODE
+	int "Poll interval, in seconds, for temperature sensors"
+
 config CMD_LL
 	depends on DEVELOPER && WR_NODE
 	bool "Build low-level commands for development/testing"

--- a/dev/dev.mk
+++ b/dev/dev.mk
@@ -2,6 +2,7 @@ obj-$(CONFIG_WR_NODE) += \
 	dev/endpoint.o \
 	dev/ep_pfilter.o \
 	dev/i2c.o \
+	dev/temperature.o \
 	dev/minic.o \
 	dev/pps_gen.o \
 	dev/syscon.o \
@@ -17,6 +18,7 @@ obj-$(CONFIG_SDB_STORAGE) += dev/sdb-storage.o

 obj-$(CONFIG_W1) +=		dev/w1.o	dev/w1-hw.o	dev/w1-shell.o
 obj-$(CONFIG_W1) +=		dev/w1-temp.o	dev/w1-eeprom.o
+obj-$(CONFIG_W1) +=		dev/temp-w1.o
 obj-$(CONFIG_UART) +=		dev/uart.o
 obj-$(CONFIG_UART_SW) +=	dev/uart-sw.o


--- a/dev/temp-w1.c
+++ b/dev/temp-w1.c
+/*
+ * This work is part of the White Rabbit project
+ *
+ * Copyright (C) 2016 GSI (www.gsi.de)
+ * Author: Alessandro rubini
+ *
+ * Released according to the GNU GPL, version 2 or any later version.
+ */
+
+#include <wrc.h>
+#include <w1.h>
+#include <temperature.h>
+
+static struct wrc_onetemp temp_w1_data[] = {
+	{"pcb", TEMP_INVALID},
+	{NULL,}
+};
+
+static unsigned long nextt;
+static int niterations;
+
+/* Returns 1 if it did something */
+static int temp_w1_refresh(struct wrc_temp *t)
+{
+
+	static int done;
+
+	if (!done) {
+		nextt = timer_get_tics() + 1000;
+		done++;
+	}
+	/* Odd iterations: send the command, even iterations: read back */
+	int phase = niterations & 1;
+	static int intervals[] = {
+		200, (1000 * CONFIG_TEMP_POLL_INTERVAL) - 200
+	};
+
+	if (time_before(timer_get_tics(), nextt))
+		return 0;
+	nextt += intervals[phase];
+	niterations++;
+
+	switch(phase) {
+	case 0:
+		w1_read_temp_bus(&wrpc_w1_bus, W1_FLAG_NOWAIT);
+		break;
+	case 1:
+		temp_w1_data[0].t =
+			w1_read_temp_bus(&wrpc_w1_bus, W1_FLAG_COLLECT);
+		break;
+	}
+	return 1;
+}
+
+/* not static at this point, because it's the only one */
+struct wrc_temp temp_w1 = {
+	.read = temp_w1_refresh,
+	.t = temp_w1_data,
+};
--- a/dev/temperature.c
+++ b/dev/temperature.c
+/*
+ * This work is part of the White Rabbit project
+ *
+ * Copyright (C) 2016 GSI (www.gsi.de)
+ * Author: Alessandro rubini
+ *
+ * Released according to the GNU GPL, version 2 or any later version.
+ */
+
+#include <wrc.h>
+#include <string.h>
+#include <temperature.h>
+#include <shell.h>
+
+extern struct wrc_temp temp_w1; /* The only one by now */
+
+/*
+ * Library functions
+ */
+uint32_t wrc_temp_get(char *name)
+{
+	struct wrc_onetemp *wt = temp_w1.t;
+
+	for (; wt->name; wt++) {
+		if (!strcmp(wt->name, name))
+			return wt->t;
+	}
+	return TEMP_INVALID;
+}
+
+struct wrc_onetemp *wrc_temp_getnext(struct wrc_onetemp *pt)
+{
+	if (!pt) /* first one */
+		return temp_w1.t;
+	if (pt[1].name)
+		return pt + 1;
+	/* get next array, if any -- none by now */
+	return NULL;
+}
+
+extern int wrc_temp_format(char *buffer, int len)
+{
+	struct wrc_onetemp *p;
+	int l = 0, i = 0;
+	int32_t t;
+
+	for (p = wrc_temp_getnext(NULL); p; p = wrc_temp_getnext(p), i++) {
+		if (l + 16 > len) {
+			l += sprintf(buffer + l, " ENOSPC");
+			return l;
+		}
+		t = p->t;
+		l += sprintf(buffer + l, "%s%s:", i ? " " : "", p->name);
+		if (t == TEMP_INVALID) {
+			l += sprintf(buffer + l, "INVALID");
+			continue;
+		}
+		if (t < 0) {
+			t = -(signed)t;
+			l += sprintf(buffer + l, "-");
+		}
+		l += sprintf(buffer + l,"%d.%04d", t >> 16,
+			     ((t & 0xffff) * 10 * 1000 >> 16));
+	}
+	return l;
+}
+
+/*
+ * The task
+ */
+void wrc_temp_init(void)
+{
+	/* Call all actors, so they can init themselves (using ->data) */
+	temp_w1.read(&temp_w1);
+}
+
+int wrc_temp_refresh(void)
+{
+	return temp_w1.read(&temp_w1);
+}
+
+/*
+ * The shell command
+ */
+
+static int cmd_temp(const char *args[])
+{
+	char buffer[80];
+
+	wrc_temp_format(buffer, sizeof(buffer));
+	pp_printf("%s\n", buffer);
+	return 0;
+}
+
+
+DEFINE_WRC_COMMAND(temp) = {
+	.name = "temp",
+	.exec = cmd_temp,
+};
+
--- a/include/temperature.h
+++ b/include/temperature.h
+/*
+ * This work is part of the White Rabbit project
+ *
+ * Copyright (C) 2016 GSI (www.gsi.de)
+ * Author: Alessandro rubini
+ *
+ * Released according to the GNU GPL, version 2 or any later version.
+ */
+#ifndef __TEMPERATURE_H__
+#define __TEMPERATURE_H__
+
+struct wrc_onetemp {
+	char *name;
+	int32_t t;  /* fixed point, 16.16 (signed!) */
+};
+#define TEMP_INVALID (0x8000 << 16)
+
+struct wrc_temp {
+	int (*read)(struct wrc_temp *);
+	void *data;
+	struct wrc_onetemp *t; /* zero-terminated */
+};
+
+/* the task */
+extern void wrc_temp_init(void);
+extern int wrc_temp_refresh(void);
+
+/* lib functions  */
+extern uint32_t wrc_temp_get(char *name);
+struct wrc_onetemp *wrc_temp_getnext(struct wrc_onetemp *);
+extern int wrc_temp_format(char *buffer, int len);
+
+#endif /* __TEMPERATURE_H__ */
--- a/monitor/monitor_ppsi.c
+++ b/monitor/monitor_ppsi.c
@@ -18,6 +18,7 @@
 #include <syscon.h>
 #include <pps_gen.h>
 #include <onewire.h>
+#include <temperature.h>
 #include "wrc_ptp.h"
 #include "hal_exports.h"
 #include "lib/ipv4.h"
@@ -350,11 +351,7 @@ int wrc_log_stats(void)
 	if (1) {
 		int32_t temp;

-		//first read the value from previous measurement,
-		//first one will be random, I know
-		temp = w1_read_temp_bus(&wrpc_w1_bus, W1_FLAG_COLLECT);
-		//then initiate new conversion for next loop cycle
-		w1_read_temp_bus(&wrpc_w1_bus, W1_FLAG_NOWAIT);
+		temp = wrc_temp_get("pcb");
 		pp_printf("temp: %d.%04d C", temp >> 16,
 			  (int)((temp & 0xffff) * 10 * 1000 >> 16));
 	}

--- a/wrc_main.c
+++ b/wrc_main.c
@@ -14,6 +14,7 @@

 #include <wrc.h>
 #include <w1.h>
+#include <temperature.h>
 #include "syscon.h"
 #include "uart.h"
 #include "endpoint.h"
@@ -210,6 +211,10 @@ struct wrc_task wrc_tasks[] = {
 	}, {
 		.name = "spll-bh",
 		.job = spll_update,
+	}, {
+		.name = "temperature",
+		.init = wrc_temp_init,
+		.job = wrc_temp_refresh,
 #ifdef CONFIG_IP
 	}, {
 		.name = "ipv4",