Implement COUNTER_* ioctl decoding

8 files changed, 251 insertions, 0 deletions

diff --git a/bundled/Makefile.am b/bundled/Makefile.am
index aaa8942ed..7ccec1ea2 100644
--- a/bundled/Makefile.am
+++ b/bundled/Makefile.am
@@ -28,6 +28,7 @@ EXTRA_DIST = \
 	linux/include/uapi/linux/btrfs_tree.h \
 	linux/include/uapi/linux/close_range.h \
 	linux/include/uapi/linux/const.h \
+	linux/include/uapi/linux/counter.h \
 	linux/include/uapi/linux/cryptouser.h \
 	linux/include/uapi/linux/dcbnl.h \
 	linux/include/uapi/linux/dm-ioctl.h \
diff --git a/bundled/linux/include/uapi/linux/counter.h b/bundled/linux/include/uapi/linux/counter.h
new file mode 100644
index 000000000..e23962d91
--- /dev/null
+++ b/bundled/linux/include/uapi/linux/counter.h
@@ -0,0 +1,154 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * Userspace ABI for Counter character devices
+ * Copyright (C) 2020 William Breathitt Gray
+ */
+#ifndef _COUNTER_H_
+#define _COUNTER_H_
+
+#include <linux/ioctl.h>
+#include <linux/types.h>
+
+/* Component type definitions */
+enum counter_component_type {
+	COUNTER_COMPONENT_NONE,
+	COUNTER_COMPONENT_SIGNAL,
+	COUNTER_COMPONENT_COUNT,
+	COUNTER_COMPONENT_FUNCTION,
+	COUNTER_COMPONENT_SYNAPSE_ACTION,
+	COUNTER_COMPONENT_EXTENSION,
+};
+
+/* Component scope definitions */
+enum counter_scope {
+	COUNTER_SCOPE_DEVICE,
+	COUNTER_SCOPE_SIGNAL,
+	COUNTER_SCOPE_COUNT,
+};
+
+/**
+ * struct counter_component - Counter component identification
+ * @type: component type (one of enum counter_component_type)
+ * @scope: component scope (one of enum counter_scope)
+ * @parent: parent ID (matching the ID suffix of the respective parent sysfs
+ *          path as described by the ABI documentation file
+ *          Documentation/ABI/testing/sysfs-bus-counter)
+ * @id: component ID (matching the ID provided by the respective *_component_id
+ *      sysfs attribute of the desired component)
+ *
+ * For example, if the Count 2 ceiling extension of Counter device 4 is desired,
+ * set type equal to COUNTER_COMPONENT_EXTENSION, scope equal to
+ * COUNTER_COUNT_SCOPE, parent equal to 2, and id equal to the value provided by
+ * the respective /sys/bus/counter/devices/counter4/count2/ceiling_component_id
+ * sysfs attribute.
+ */
+struct counter_component {
+	__u8 type;
+	__u8 scope;
+	__u8 parent;
+	__u8 id;
+};
+
+/* Event type definitions */
+enum counter_event_type {
+	/* Count value increased past ceiling */
+	COUNTER_EVENT_OVERFLOW,
+	/* Count value decreased past floor */
+	COUNTER_EVENT_UNDERFLOW,
+	/* Count value increased past ceiling, or decreased past floor */
+	COUNTER_EVENT_OVERFLOW_UNDERFLOW,
+	/* Count value reached threshold */
+	COUNTER_EVENT_THRESHOLD,
+	/* Index signal detected */
+	COUNTER_EVENT_INDEX,
+};
+
+/**
+ * struct counter_watch - Counter component watch configuration
+ * @component: component to watch when event triggers
+ * @event: event that triggers (one of enum counter_event_type)
+ * @channel: event channel (typically 0 unless the device supports concurrent
+ *	     events of the same type)
+ */
+struct counter_watch {
+	struct counter_component component;
+	__u8 event;
+	__u8 channel;
+};
+
+/*
+ * Queues a Counter watch for the specified event.
+ *
+ * The queued watches will not be applied until COUNTER_ENABLE_EVENTS_IOCTL is
+ * called.
+ */
+#define COUNTER_ADD_WATCH_IOCTL _IOW(0x3E, 0x00, struct counter_watch)
+/*
+ * Enables monitoring the events specified by the Counter watches that were
+ * queued by COUNTER_ADD_WATCH_IOCTL.
+ *
+ * If events are already enabled, the new set of watches replaces the old one.
+ * Calling this ioctl also has the effect of clearing the queue of watches added
+ * by COUNTER_ADD_WATCH_IOCTL.
+ */
+#define COUNTER_ENABLE_EVENTS_IOCTL _IO(0x3E, 0x01)
+/*
+ * Stops monitoring the previously enabled events.
+ */
+#define COUNTER_DISABLE_EVENTS_IOCTL _IO(0x3E, 0x02)
+
+/**
+ * struct counter_event - Counter event data
+ * @timestamp: best estimate of time of event occurrence, in nanoseconds
+ * @value: component value
+ * @watch: component watch configuration
+ * @status: return status (system error number)
+ */
+struct counter_event {
+	__aligned_u64 timestamp;
+	__aligned_u64 value;
+	struct counter_watch watch;
+	__u8 status;
+};
+
+/* Count direction values */
+enum counter_count_direction {
+	COUNTER_COUNT_DIRECTION_FORWARD,
+	COUNTER_COUNT_DIRECTION_BACKWARD,
+};
+
+/* Count mode values */
+enum counter_count_mode {
+	COUNTER_COUNT_MODE_NORMAL,
+	COUNTER_COUNT_MODE_RANGE_LIMIT,
+	COUNTER_COUNT_MODE_NON_RECYCLE,
+	COUNTER_COUNT_MODE_MODULO_N,
+};
+
+/* Count function values */
+enum counter_function {
+	COUNTER_FUNCTION_INCREASE,
+	COUNTER_FUNCTION_DECREASE,
+	COUNTER_FUNCTION_PULSE_DIRECTION,
+	COUNTER_FUNCTION_QUADRATURE_X1_A,
+	COUNTER_FUNCTION_QUADRATURE_X1_B,
+	COUNTER_FUNCTION_QUADRATURE_X2_A,
+	COUNTER_FUNCTION_QUADRATURE_X2_B,
+	COUNTER_FUNCTION_QUADRATURE_X4,
+};
+
+/* Signal values */
+enum counter_signal_level {
+	COUNTER_SIGNAL_LEVEL_LOW,
+	COUNTER_SIGNAL_LEVEL_HIGH,
+};
+
+/* Action mode values */
+enum counter_synapse_action {
+	COUNTER_SYNAPSE_ACTION_NONE,
+	COUNTER_SYNAPSE_ACTION_RISING_EDGE,
+	COUNTER_SYNAPSE_ACTION_FALLING_EDGE,
+	COUNTER_SYNAPSE_ACTION_BOTH_EDGES,
+};
+
+#endif /* _COUNTER_H_ */
diff --git a/src/counter_ioctl.c b/src/counter_ioctl.c
new file mode 100644
index 000000000..5ed2fb750
--- /dev/null
+++ b/src/counter_ioctl.c
@@ -0,0 +1,70 @@
+/*
+ * Copyright (c) 2021 Eugene Syromyatnikov <evgsyr@gmail.com>.
+ * All rights reserved.
+ *
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ */
+
+#include "defs.h"
+
+#include <linux/ioctl.h>
+#include <linux/counter.h>
+
+#include "xlat/counter_ioctl_component_types.h"
+#include "xlat/counter_ioctl_event_types.h"
+#include "xlat/counter_ioctl_scopes.h"
+
+
+static void
+print_struct_counter_component(const struct counter_component *const cc)
+{
+	tprint_struct_begin();
+	PRINT_FIELD_XVAL(*cc, type, counter_ioctl_component_types,
+			 "COUNTER_COMPONENT_???");
+	tprint_struct_next();
+	PRINT_FIELD_XVAL(*cc, type, counter_ioctl_component_scopes,
+			 "COUNTER_SCOPE_???");
+	tprint_struct_next();
+	PRINT_FIELD_U(*cc, parent);
+	tprint_struct_next();
+	PRINT_FIELD_U(*cc, id);
+	tprint_struct_end();
+}
+
+static void
+print_struct_counter_watch(struct tcb *const tcp, const kernel_ulong_t addr)
+{
+	CHECK_IOCTL_SIZE(COUNTER_ADD_WATCH_IOCTL, 6);
+	CHECK_TYPE_SIZE(struct counter_watch, 6);
+	struct counter_watch w;
+
+	if (umove_or_printaddr(tcp, addr, &w))
+		return;
+
+	tprint_struct_begin();
+	PRINT_FIELD_OBJ_PTR(w, component, print_struct_counter_component);
+	tprint_struct_next();
+	PRINT_FIELD_XVAL(w, event, counter_ioctl_events,
+			 "COUNTER_EVENT_???");
+	tprint_struct_next();
+	PRINT_FIELD_U(w, channel);
+	tprint_struct_end();
+}
+
+int
+counter_ioctl(struct tcb *const tcp, const unsigned int code,
+	      const kernel_ulong_t arg)
+{
+	switch (code) {
+	case COUNTER_ADD_WATCH_IOCTL:
+		tprint_arg_next();
+		print_struct_counter_watch(tcp, arg);
+
+	case COUNTER_ENABLE_EVENTS_IOCTL:
+	case COUNTER_DISABLE_EVENTS_IOCTL:
+		return RVAL_IOCTL_DECODED;
+
+	default:
+		return RVAL_DECODED;
+	}
+}
diff --git a/src/defs.h b/src/defs.h
index c454b0b09..482bc236f 100644
--- a/src/defs.h
+++ b/src/defs.h
@@ -1356,6 +1356,7 @@ extern int								\
 name ## _ioctl(struct tcb *, unsigned int request, kernel_ulong_t arg)	\
 /* End of DECL_IOCTL definition. */
 
+DECL_IOCTL(counter);
 DECL_IOCTL(dm);
 DECL_IOCTL(evdev);
 DECL_IOCTL(fs_0x94);
diff --git a/src/ioctl.c b/src/ioctl.c
index 1965af32c..d75c04829 100644
--- a/src/ioctl.c
+++ b/src/ioctl.c
@@ -362,6 +362,8 @@ ioctl_decode(struct tcb *tcp)
 		return perf_ioctl(tcp, code, arg);
 	case '=': /* 0x3d */
 		return ptp_ioctl(tcp, code, arg);
+	case '>': /* 0x3e */
+		return counter_ioctl(tcp, code, arg);
 	case 'E':
 		return evdev_ioctl(tcp, code, arg);
 	case 'I':
diff --git a/src/xlat/counter_ioctl_component_types.in b/src/xlat/counter_ioctl_component_types.in
new file mode 100644
index 000000000..a99ccb544
--- /dev/null
+++ b/src/xlat/counter_ioctl_component_types.in
@@ -0,0 +1,9 @@
+#enum
+#value_indexed
+#unconditional
+COUNTER_COMPONENT_NONE			0
+COUNTER_COMPONENT_SIGNAL		1
+COUNTER_COMPONENT_COUNT			2
+COUNTER_COMPONENT_FUNCTION		3
+COUNTER_COMPONENT_SYNAPSE_ACTION	4
+COUNTER_COMPONENT_EXTENSION		5
diff --git a/src/xlat/counter_ioctl_event_types.in b/src/xlat/counter_ioctl_event_types.in
new file mode 100644
index 000000000..fa5d1d406
--- /dev/null
+++ b/src/xlat/counter_ioctl_event_types.in
@@ -0,0 +1,8 @@
+#enum
+#value_indexed
+#unconditional
+COUNTER_EVENT_OVERFLOW			0
+COUNTER_EVENT_UNDERFLOW			1
+COUNTER_EVENT_OVERFLOW_UNDERFLOW	2
+COUNTER_EVENT_THRESHOLD			3
+COUNTER_EVENT_INDEX			4
diff --git a/src/xlat/counter_ioctl_scopes.in b/src/xlat/counter_ioctl_scopes.in
new file mode 100644
index 000000000..cd115716f
--- /dev/null
+++ b/src/xlat/counter_ioctl_scopes.in
@@ -0,0 +1,6 @@
+#enum
+#value_indexed
+#unconditional
+COUNTER_SCOPE_DEVICE	0
+COUNTER_SCOPE_SIGNAL	1
+COUNTER_SCOPE_COUNT	2