move fastrpc to project root

The FastRPC implementation is loosely related to the sensor shell. It is
useful to provide interfaces over FastRPC for sensor DSP firmware, and
enables the sensor shell to provide most physical sensors. However, the
FastRPC implementation has no meaningful connection with the sensor
shell in terms of code. Move the FastRPC implementation to the project
root to make it more intuitive to install and use and to separate it
from a distinct project.

Makefile

@@ -1,65 +0,0 @@
-#
-# Build system
-#
-# Copyright (C) 2022 Richard Acayan
-#
-# This file is part of sensh.
-#
-# Sensh is free software: you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation, either version 3 of the License, or
-# (at your option) any later version.
-#
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License
-# along with this program.  If not, see <https://www.gnu.org/licenses/>.
-#
-
-QMIC = qmic
-CC = gcc
-LIBS = -lprotobuf-c -lqrtr
-CFLAGS = -Wall -Wextra -Wpedantic -Ibuild -I.
-PROTOC_C = protoc-c
-
-build/sensh: build/sensh.o build/qmi_sns_client.o build/sns_client_event_msg.pb-c.o build/sns_client_request_msg.pb-c.o build/sns_proximity_event.pb-c.o build/sns_std_attr_event.pb-c.o build/sns_std_attr_req.pb-c.o build/sns_std_sensor_event.pb-c.o build/sns_std_suid.pb-c.o build/sns_suid_event.pb-c.o build/sns_suid_req.pb-c.o
-	$(CC) -o build/sensh build/sensh.o build/qmi_sns_client.o build/sns_client_event_msg.pb-c.o build/sns_client_request_msg.pb-c.o build/sns_proximity_event.pb-c.o build/sns_std_attr_event.pb-c.o build/sns_std_attr_req.pb-c.o build/sns_std_sensor_event.pb-c.o build/sns_std_suid.pb-c.o build/sns_suid_event.pb-c.o build/sns_suid_req.pb-c.o $(LIBS)
-
-build/qmi_%.d: build/qmi_%.c
-	$(CC) $(CFLAGS) -MM -MT build/$*.o -o $@ $<
-
-build/%.pb-c.d: build/%.pb-c.c
-	$(CC) $(CFLAGS) -MM -MT build/$*.o -o $@ $<
-
-build/%.d: %.c
-	$(CC) $(CFLAGS) -MM -MT build/$*.o -o $@ $<
-
-build/qmi_%.o: build/qmi_%.c
-	$(CC) $(CFLAGS) -c -o $@ $<
-
-build/%.pb-c.o: build/%.pb-c.c
-	$(CC) $(CFLAGS) -c -o $@ $<
-
-build/%.o: %.c
-	$(CC) $(CFLAGS) -c -o $@ $<
-
-build/qmi_%.c build/qmi_%.h: qmi/%.qmi
-	cd build && $(QMIC) -k < ../$<
-
-build/%.pb-c.c build/%.pb-c.h: protobuf/%.proto
-	$(PROTOC_C) --c_out=build -Iprotobuf $<
-
-include build/sensh.d
-include build/qmi_sns_client.d
-include build/sns_client_event_msg.pb-c.d
-include build/sns_client_request_msg.pb-c.d
-include build/sns_proximity_event.pb-c.d
-include build/sns_std_attr_event.pb-c.d
-include build/sns_std_attr_req.pb-c.d
-include build/sns_std_sensor_event.pb-c.d
-include build/sns_std_suid.pb-c.d
-include build/sns_suid_event.pb-c.d
-include build/sns_suid_req.pb-c.d

README.md

@@ -1,64 +1,150 @@
-This is a proof-of-concept for interacting with the Snapdragon Sensor Core
-using the reverse-engineered protocol buffers. It was made to try to
-initialize it, but the Pixel 3a is missing some sensors once the firmware is
-loaded.
+This directory contains a FastRPC ioctl wrapper and a reverse tunnel.
 
-A best effort is made to prefix all log messages with `sensh: ` so it's clear
-which lines were entered by the user.
+FastRPC is used to communicate with the Context Hub Runtime Environment, a
+program on the DSP that manages sensors, and to serve files to remote
+processors.
 
-# Requirements
+# Wrapper function
 
- - gcc
- - libqrtr
- - meson or make
- - protobuf-c
- - qmic (optional for regenerating QMI, at https://github.com/andersson/qmic)
+The wrapper function is designed so that the ioctl arguments do not need to be
+constructed for each remote method. Instead, it accepts an open file descriptor,
+handle, method definition, and arguments to the remote method using `va_args`.
+This makes it relatively easy to add remote methods without the use of the QAIC
+interface compiler or a free software alternative.
 
-# Installation
+## Installation
 
-This can be compiled using Meson:
+You can build and install this project using meson:
 
-    $ meson setup build
-    $ ninja -C build
+    ~/sensh/fastrpc $ meson setup build
+    ~/sensh/fastrpc $ ninja -C build
+    ~/sensh/fastrpc # ninja -C build install
 
-There is also a Makefile to compile this, if you can get it to work:
+## Usage
 
-    $ mkdir build
-    $ make -k
+Making already-defined method calls is relatively straightforward, depending on
+the remote method that you're calling. You just need the function definition, an
+open file descriptor, the handle, and the arguments for it.
 
-# Usage
+    uint32_t prev_ctx, prev_result, nested_outbufs_len;
+    uint32_t ctx, nested_handle, nested_sc, nested_inbufs_len;
+    uint32_t nested_inbufs_size;
+    const void *nested_outbufs;
+    void *nested_inbufs;
+    int fd;
 
-Sensh doesn't automatically track, probe, or look up sensors; that is for a full
-implementation. Instead, it expects you to look up the sensor and copy the ID
-with your terminal emulator:
+    ret = fastrpc2(&adsp_listener_next2_def, fd, ADSP_LISTENER_HANDLE,
+    	       prev_ctx,
+    	       prev_result,
+    	       nested_outbufs_len, nested_outbufs,
+    	       &ctx,
+    	       &nested_handle,
+    	       &nested_sc,
+    	       &nested_inbufs_len,
+    	       nested_inbufs_size, nested_inbufs);
 
-    lookup accel_cal
-    sensh: accel_cal sensor found: A1392FDF217B7D9EI6648AED8C04DDFB9
-    attr A1392FDF217B7D9EI6648AED8C04DDFB9
-    sensh: name: ASH_CAL
-    sensh: vendor: GOOGLE
-    sensh: type: accel_cal
-    sensh: version: 1
-    sensh: api: sns_cal.proto
-    sensh: rates: 10.000000
-    sensh: stream type: 1
-    sensh: physical sensor: 0
-    sensh: available: 1
+All inputs are specified before all outputs. Words in the first (called "prim",
+or primary in QAIC-generated code) input and output buffers go in the form of
+`uint32_t` arguments. Each buffer is accepted as a `uint32_t` length and a
+pointer.
 
-You can send 3 messages: lookup, attr, and watch. The lookup command returns
-SUIDs for the passed data type. The attr command returns attributes for the
-sensor. Finally, the watch command tells the sensor core to send events from a
-sensor whenever the sensor's value changes.
+### Creating function definitions
 
-An EOF (normally Ctrl+D) is enough to exit the shell unless the sensor core
-died.
+Assuming you already have knowledge about the remote method to call, you must
+first write a function definition for it. A function definition is a struct with
+information on its method ID and the arguments it accepts.
 
-# References
+First, the method ID is taken from the first argument of the
+`REMOTE_SCALARS_MAKE()` macro or the second argument of the
+`REMOTE_SCALARS_MAKEX()` macro
+(defined [here](https://android.googlesource.com/platform/external/fastrpc/+/d6d6e3bba244e40e6043bd687f4cacf090a767b5/inc/remote.h#80)).
 
-The following sources were used as reference:
+Example:
 
- - [https://android.googlesource.com/platform/system/chre](https://android.googlesource.com/platform/system/chre)
- - [https://android.googlesource.com/platform/external/fastrpc](https://android.googlesource.com/platform/external/fastrpc)
- - [https://github.com/calebccff/sensordaemon-re](https://github.com/calebccff/sensordaemon-re)
- - [https://gitlab.freedesktop.org/mobile-broadband/libqmi/-/merge\_requests/346](https://gitlab.freedesktop.org/mobile-broadband/libqmi/-/merge_requests/346)
- - [https://git.linaro.org/landing-teams/working/qualcomm/fastrpc.git](https://git.linaro.org/landing-teams/working/qualcomm/fastrpc.git)
+    REMOTE_SCALARS_MAKE(4, 2, 2)
+
+has the method 4.
+
+Next, information on how many arguments it takes must be specified. There are
+four types of arguments:
+
+- 32-bit input words in the first input buffer, excluding lengths for the input
+  and output buffers
+- 32-bit output words in the first output buffer
+- input buffers, excluding the first
+- output buffers, excluding the first
+
+To get the size of the first input and output buffers, a dump must be consulted,
+or the prim argument of generated C files:
+
+    invoking via fastrpc, handle 3, method 4, 2 inbufs, 2 outbufs, 0 inhandles, 0 outhandles
+    fastrpc argument 00000000FFFFFFFF0000000000000000 // 16 bytes, or 4 words
+    fastrpc argument 
+    invoking via fastrpc, handle 5, method 4, 1 inbufs, 1 outbufs, 0 inhandles, 0 outhandles
+    fastrpc return 91000000000000000002020029000000 // 16 bytes, or 4 words
+    fastrpc return 
+
+Since there are 2 input buffers excluding the first (these can have a variable
+size), 2 must be subtracted from the 4 input words. These will be provided by
+the wrapper as the sizes for the variable-length input and output buffers.
+
+Counting each of these will give the numbers needed for the function definition.
+
+A function definition looks like:
+
+    const struct fastrpc_function_def_interp2 adsp_listener_next2_def = {
+    	.msg_id = 4,
+    	.in_nums = 2,
+    	.in_bufs = 1,
+    	.out_nums = 4,
+    	.out_bufs = 1,
+    };
+
+or:
+
+    #define DEFINE_REMOTE_PROCEDURE(mid, name,				\
+    				innums, inbufs,				\
+    				outnums, outbufs)			\
+    	const struct fastrpc_function_def_interp2 name##_def = {	\
+    		.msg_id = mid,						\
+    		.in_nums = innums,					\
+    		.in_bufs = inbufs,					\
+    		.out_nums = outnums,					\
+    		.out_bufs = outbufs,					\
+    	};
+
+    DEFINE_REMOTE_PROCEDURE(4, adsp_listener_next2, 2, 1, 4, 1)
+
+# Reverse tunnel
+
+The reverse tunnel calls the `adsp_listener_next2` remote method to receive
+method calls for the Application Processor.
+
+Interfaces are initialized in the `start_reverse_tunnel` function, in hexagonrpcd/rpcd.c.
+
+## HexagonFS
+
+The reverse tunnel's `apps_std` interface serves files to the remote processor.
+These files are searched for in:
+
+    Physical file/dir			Android file/dir
+    /usr/share/qcom/acdb			/vendor/etc/acdbdata
+    /usr/share/qcom/dsp			/vendor/dsp
+    /usr/share/qcom/sensors/config		/vendor/etc/sensors/config
+    /usr/share/qcom/sensors/registry	/mnt/vendor/persist/sensors/registry/registry
+    /usr/share/qcom/sensors/sns_reg.conf	/vendor/etc/sensors/sns_reg_config
+
+These files and directories should be populated with files from your device's
+Android firmware.
+
+# Future plans
+
+Reverse tunnels are separated by the process that opens the file descriptor and
+cannot service requests from other processes that do not share the same file
+descriptor. There should be some daemon that opens the device and allows clients
+to send requests.
+
+FastRPC may be the way to offload work to the DSPs. When a FastRPC function call
+is made, the `<name>_skel_invoke` function in a shared object named
+`lib<name>_skel.so` is called on the DSP. Further investigation is needed to
+make a working build system for this.

chrecd/interfaces.c

@@ -1,7 +1,7 @@
 /*
- * Sensor SUID
+ * FastRPC interface list for building method definitions
  *
- * Copyright (C) 2022 Richard Acayan
+ * Copyright (C) 2023 The Sensor Shell Contributors
  *
  * This file is part of sensh.
  *
@@ -19,9 +19,6 @@
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 
-syntax = "proto2";
+#define HEXAGONRPC_BUILD_METHOD_DEFINITIONS 1
 
-message sns_std_suid {
-	required fixed64 suid_low = 1;
-	required fixed64 suid_high = 2;
-}
+#include "interfaces/chre_slpi.def"

chrecd/main.c

@@ -0,0 +1,124 @@
+/*
+ * CHRE client daemon entry point
+ *
+ * Copyright (C) 2023 The Sensor Shell Contributors
+ *
+ * This file is part of sensh.
+ *
+ * Sensh is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include <errno.h>
+#include <libhexagonrpc/fastrpc.h>
+#include <libhexagonrpc/interfaces/remotectl.def>
+#include <libhexagonrpc/session.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "interfaces/chre_slpi.def"
+
+/* TODO move these to libhexagonrpc since most clients use them */
+static int remotectl_open(int fd, char *name, struct fastrpc_context **ctx, void (*err_cb)(const char *err))
+{
+	uint32_t handle;
+	int32_t dlret;
+	char err[256];
+	int ret;
+
+	ret = fastrpc2(&remotectl_open_def, fd, REMOTECTL_HANDLE,
+		       strlen(name) + 1, name,
+		       &handle,
+		       &dlret,
+		       256, err);
+
+	if (ret == -1) {
+		err_cb(strerror(errno));
+		return ret;
+	}
+
+	if (dlret == -5) {
+		err_cb(err);
+		return dlret;
+	}
+
+	*ctx = fastrpc_create_context(fd, handle);
+
+	return ret;
+}
+
+static int remotectl_close(struct fastrpc_context *ctx, void (*err_cb)(const char *err))
+{
+	uint32_t dlret;
+	char err[256];
+	int ret;
+
+	ret = fastrpc2(&remotectl_close_def, ctx->fd, REMOTECTL_HANDLE,
+		       ctx->handle,
+		       &dlret,
+		       256, err);
+
+	if (ret == -1) {
+		err_cb(strerror(errno));
+		return ret;
+	}
+
+	fastrpc_destroy_context(ctx);
+
+	return ret;
+}
+
+static void remotectl_err(const char *err)
+{
+	fprintf(stderr, "Could not remotectl: %s\n", err);
+}
+
+static int chre_slpi_start_thread(struct fastrpc_context *ctx)
+{
+	return fastrpc(&chre_slpi_start_thread_def, ctx);
+}
+
+static int chre_slpi_wait_on_thread_exit(struct fastrpc_context *ctx)
+{
+	return fastrpc(&chre_slpi_wait_on_thread_exit_def, ctx);
+}
+
+int main()
+{
+	struct fastrpc_context *ctx;
+	int fd, ret;
+
+	fd = hexagonrpc_fd_from_env();
+	if (fd == -1)
+		return 1;
+
+	ret = remotectl_open(fd, "chre_slpi", &ctx, remotectl_err);
+	if (ret)
+		return 1;
+
+	ret = chre_slpi_start_thread(ctx);
+	if (ret) {
+		fprintf(stderr, "Could not start CHRE\n");
+		goto err;
+	}
+
+	ret = chre_slpi_wait_on_thread_exit(ctx);
+	if (ret) {
+		fprintf(stderr, "Could not wait for CHRE thread\n");
+		goto err;
+	}
+
+err:
+	remotectl_close(ctx, remotectl_err);
+}

chrecd/meson.build

@@ -0,0 +1,9 @@
+executable('chrecd',
+  'interfaces.c',
+  'main.c',
+  c_args : ['-Wall', '-Wextra', '-Wpedantic'],
+  include_directories : include,
+  install : true,
+  link_with : libhexagonrpc,
+  install_dir : client_target,
+)

fastrpc/README.md

@@ -1,150 +0,0 @@
-This directory contains a FastRPC ioctl wrapper and a reverse tunnel.
-
-FastRPC is used to communicate with the Context Hub Runtime Environment, a
-program on the DSP that manages sensors, and to serve files to remote
-processors.
-
-# Wrapper function
-
-The wrapper function is designed so that the ioctl arguments do not need to be
-constructed for each remote method. Instead, it accepts an open file descriptor,
-handle, method definition, and arguments to the remote method using `va_args`.
-This makes it relatively easy to add remote methods without the use of the QAIC
-interface compiler or a free software alternative.
-
-## Installation
-
-You can build and install this project using meson:
-
-    ~/sensh/fastrpc $ meson setup build
-    ~/sensh/fastrpc $ ninja -C build
-    ~/sensh/fastrpc # ninja -C build install
-
-## Usage
-
-Making already-defined method calls is relatively straightforward, depending on
-the remote method that you're calling. You just need the function definition, an
-open file descriptor, the handle, and the arguments for it.
-
-    uint32_t prev_ctx, prev_result, nested_outbufs_len;
-    uint32_t ctx, nested_handle, nested_sc, nested_inbufs_len;
-    uint32_t nested_inbufs_size;
-    const void *nested_outbufs;
-    void *nested_inbufs;
-    int fd;
-
-    ret = fastrpc2(&adsp_listener_next2_def, fd, ADSP_LISTENER_HANDLE,
-    	       prev_ctx,
-    	       prev_result,
-    	       nested_outbufs_len, nested_outbufs,
-    	       &ctx,
-    	       &nested_handle,
-    	       &nested_sc,
-    	       &nested_inbufs_len,
-    	       nested_inbufs_size, nested_inbufs);
-
-All inputs are specified before all outputs. Words in the first (called "prim",
-or primary in QAIC-generated code) input and output buffers go in the form of
-`uint32_t` arguments. Each buffer is accepted as a `uint32_t` length and a
-pointer.
-
-### Creating function definitions
-
-Assuming you already have knowledge about the remote method to call, you must
-first write a function definition for it. A function definition is a struct with
-information on its method ID and the arguments it accepts.
-
-First, the method ID is taken from the first argument of the
-`REMOTE_SCALARS_MAKE()` macro or the second argument of the
-`REMOTE_SCALARS_MAKEX()` macro
-(defined [here](https://android.googlesource.com/platform/external/fastrpc/+/d6d6e3bba244e40e6043bd687f4cacf090a767b5/inc/remote.h#80)).
-
-Example:
-
-    REMOTE_SCALARS_MAKE(4, 2, 2)
-
-has the method 4.
-
-Next, information on how many arguments it takes must be specified. There are
-four types of arguments:
-
-- 32-bit input words in the first input buffer, excluding lengths for the input
-  and output buffers
-- 32-bit output words in the first output buffer
-- input buffers, excluding the first
-- output buffers, excluding the first
-
-To get the size of the first input and output buffers, a dump must be consulted,
-or the prim argument of generated C files:
-
-    invoking via fastrpc, handle 3, method 4, 2 inbufs, 2 outbufs, 0 inhandles, 0 outhandles
-    fastrpc argument 00000000FFFFFFFF0000000000000000 // 16 bytes, or 4 words
-    fastrpc argument 
-    invoking via fastrpc, handle 5, method 4, 1 inbufs, 1 outbufs, 0 inhandles, 0 outhandles
-    fastrpc return 91000000000000000002020029000000 // 16 bytes, or 4 words
-    fastrpc return 
-
-Since there are 2 input buffers excluding the first (these can have a variable
-size), 2 must be subtracted from the 4 input words. These will be provided by
-the wrapper as the sizes for the variable-length input and output buffers.
-
-Counting each of these will give the numbers needed for the function definition.
-
-A function definition looks like:
-
-    const struct fastrpc_function_def_interp2 adsp_listener_next2_def = {
-    	.msg_id = 4,
-    	.in_nums = 2,
-    	.in_bufs = 1,
-    	.out_nums = 4,
-    	.out_bufs = 1,
-    };
-
-or:
-
-    #define DEFINE_REMOTE_PROCEDURE(mid, name,				\
-    				innums, inbufs,				\
-    				outnums, outbufs)			\
-    	const struct fastrpc_function_def_interp2 name##_def = {	\
-    		.msg_id = mid,						\
-    		.in_nums = innums,					\
-    		.in_bufs = inbufs,					\
-    		.out_nums = outnums,					\
-    		.out_bufs = outbufs,					\
-    	};
-
-    DEFINE_REMOTE_PROCEDURE(4, adsp_listener_next2, 2, 1, 4, 1)
-
-# Reverse tunnel
-
-The reverse tunnel calls the `adsp_listener_next2` remote method to receive
-method calls for the Application Processor.
-
-Interfaces are initialized in the `start_reverse_tunnel` function, in hexagonrpcd/rpcd.c.
-
-## HexagonFS
-
-The reverse tunnel's `apps_std` interface serves files to the remote processor.
-These files are searched for in:
-
-    Physical file/dir			Android file/dir
-    /usr/share/qcom/acdb			/vendor/etc/acdbdata
-    /usr/share/qcom/dsp			/vendor/dsp
-    /usr/share/qcom/sensors/config		/vendor/etc/sensors/config
-    /usr/share/qcom/sensors/registry	/mnt/vendor/persist/sensors/registry/registry
-    /usr/share/qcom/sensors/sns_reg.conf	/vendor/etc/sensors/sns_reg_config
-
-These files and directories should be populated with files from your device's
-Android firmware.
-
-# Future plans
-
-Reverse tunnels are separated by the process that opens the file descriptor and
-cannot service requests from other processes that do not share the same file
-descriptor. There should be some daemon that opens the device and allows clients
-to send requests.
-
-FastRPC may be the way to offload work to the DSPs. When a FastRPC function call
-is made, the `<name>_skel_invoke` function in a shared object named
-`lib<name>_skel.so` is called on the DSP. Further investigation is needed to
-make a working build system for this.

fastrpc/meson.build

@@ -1,9 +0,0 @@
-project('fastrpc', 'c')
-
-include = include_directories('include')
-
-subdir('libhexagonrpc')
-
-subdir('hexagonrpcd')
-
-subdir('tests')

hexagonrpcd/interfaces.c

@@ -24,5 +24,3 @@
 #include "interfaces/adsp_default_listener.def"
 #include "interfaces/apps_std.def"
 #include "interfaces/adsp_listener.def"
-#include "interfaces/chre_slpi.def"
-#include "interfaces/remotectl.def"