test: Add mbox helpers for unit/integration tests
The helpers enable initialising the mbox context to the point that
dispatch_mbox() can be usefully called in a controlled environment, and
then testing any side-effects that resulted.
Change-Id: I590841f70dd51e0993b491e537ed4a73ab696e14
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
diff --git a/test/mbox.c b/test/mbox.c
new file mode 100644
index 0000000..dc049ce
--- /dev/null
+++ b/test/mbox.c
@@ -0,0 +1,300 @@
+/*
+ * MBox Daemon Test File
+ *
+ * Copyright 2017 IBM
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+#define _GNU_SOURCE /* fallocate */
+#include <assert.h>
+#include <fcntl.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/mman.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+#include "mbox.h"
+#include "mboxd_flash.h"
+#include "mboxd_lpc.h"
+#include "mboxd_msg.h"
+#include "mboxd_windows.h"
+
+#include "test/mbox.h"
+
+#define STEP 16
+
+void dump_buf(const uint8_t *buf, size_t len)
+{
+ int i;
+
+ for (i = 0; i < len; i += STEP) {
+ int delta;
+ int max;
+ int j;
+
+ delta = len - i;
+ max = delta > STEP ? STEP : delta;
+
+ printf("0x%08x:\t", i);
+ for (j = 0; j < max; j++)
+ printf("0x%02x, ", buf[i + j]);
+
+ printf("\n");
+ }
+ printf("\n");
+}
+
+/*
+ * Because we are using a file and not a pipe for the mbox file descriptor we
+ * need to handle a difference in behaviour. For a given command and response
+ * sequence the first 16 bytes of the file are occupied by the mbox command.
+ * The response occupies the following 14 bytes for a total of 30 bytes.
+ *
+ * We also have to ensure we lseek() to reset the file descriptor offset back
+ * to the start of the file before dispatching the mbox command.
+ */
+
+/* Macros for handling the pipe/file discrepancy */
+#define RESPONSE_OFFSET 16
+#define RESPONSE_SIZE 14
+
+int mbox_cmp(struct mbox_context *context, const uint8_t *expected, size_t len)
+{
+ struct stat details;
+ uint8_t *map;
+ int rc;
+ int fd;
+
+ fd = context->fds[MBOX_FD].fd;
+ fstat(fd, &details);
+
+ map = mmap(NULL, details.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
+ assert(map != MAP_FAILED);
+ assert(details.st_size >= (RESPONSE_OFFSET + len));
+
+ rc = memcmp(expected, &map[RESPONSE_OFFSET], len);
+
+ if (rc != 0) {
+ printf("\nMBOX state (%ld):\n", details.st_size);
+ dump_buf(map, details.st_size);
+ printf("Expected response (%lu):\n", len);
+ dump_buf(expected, len);
+ }
+
+ munmap(map, details.st_size);
+
+ return rc;
+}
+
+int mbox_command_write(struct mbox_context *context, const uint8_t *command,
+ size_t len)
+{
+ size_t remaining;
+ int rc;
+ int fd;
+
+ fd = context->fds[MBOX_FD].fd;
+ rc = lseek(fd, 0, SEEK_SET);
+ if (rc != 0)
+ return -1;
+
+ remaining = len;
+ while (remaining > 0) {
+ rc = write(fd, command, remaining);
+ if (rc < 0)
+ goto out;
+ remaining -= rc;
+ }
+
+ rc = lseek(fd, 0, SEEK_SET);
+ if (rc != 0)
+ return -1;
+
+out:
+ return rc;
+}
+
+int mbox_command_dispatch(struct mbox_context *context, const uint8_t *command,
+ size_t len)
+{
+ uint8_t status;
+ int rc;
+
+ rc = mbox_command_write(context, command, len);
+ if (rc < 0)
+ return rc;
+
+ rc = dispatch_mbox(context);
+ if (rc < 0)
+ return -rc;
+
+ /*
+ * The aspeed-lpc-ctrl driver implements mailbox register access
+ * through the usual read()/write() chardev interface.
+ *
+ * The typical access sequence is:
+ *
+ * 1. Read all the registers out
+ * 2. Perform the action specified
+ * 3. Write a response to the registers.
+ *
+ * For the tests the "device" file descriptor is backed by a temporary
+ * file. The above sequence leads to a file-size of 30 bytes: 16 bytes
+ * for the issued command, followed by a 14-byte response.
+ *
+ * However, the typical access pattern isn't the only access pattern.
+ * Individual byte registers can be accessed by lseek()'ing on the
+ * device's file descriptor and issuing read() or write() as desired.
+ * The daemon uses this property to manage the BMC status byte, and the
+ * implementation cleans up after status byte operations by lseek()'ing
+ * back to offset zero.
+ *
+ * Thus for the BMC_EVENT_ACK command the file only reaches a size of
+ * 16 bytes; the daemon's response overwrites the first 14 bytes of the
+ * command injected by the tests.
+ *
+ * The consequence of this is that the response status byte can either
+ * appear at offset 13, or offset 29, depending on the command.
+ *
+ * However, regardless of what command is issued the response data is
+ * written to the device and the file descriptor is left in the
+ * post-write() state. This means the status byte can always be
+ * accessed relative to the current position by an lseek() of type
+ * SEEK_CUR for offset -1.
+ *
+ */
+ rc = lseek(context->fds[MBOX_FD].fd, -1, SEEK_CUR);
+ if (rc < 0)
+ return rc;
+
+ rc = read(context->fds[MBOX_FD].fd, &status, sizeof(status));
+ if (rc < 0)
+ return rc;
+
+ return status;
+}
+
+struct mbox_test_context {
+ struct tmpf mbox;
+ struct tmpf flash;
+ struct tmpf lpc;
+ struct mbox_context context;
+} test;
+
+void cleanup(void)
+{
+ tmpf_destroy(&test.mbox);
+ tmpf_destroy(&test.flash);
+ tmpf_destroy(&test.lpc);
+}
+
+int __init_mbox_dev(struct mbox_context *context, const char *path);
+int __init_lpc_dev(struct mbox_context *context, const char *path);
+
+struct mbox_context *mbox_create_test_context(int n_windows, size_t len)
+{
+ int rc;
+
+ mbox_vlog = &mbox_log_console;
+ verbosity = 2;
+
+ atexit(cleanup);
+
+ rc = tmpf_init(&test.mbox, "mboxXXXXXX");
+ assert(rc == 0);
+
+ rc = tmpf_init(&test.flash, "flashXXXXXX");
+ assert(rc == 0);
+
+ rc = tmpf_init(&test.lpc, "lpcXXXXXX");
+ assert(rc == 0);
+
+ test.context.windows.num = n_windows;
+ test.context.windows.default_size = len;
+
+ /*
+ * We need to control MBOX_FD, so don't call __init_mbox_dev().
+ * Instead, insert our temporary file's fd directly into the context
+ */
+ test.context.fds[MBOX_FD].fd = test.mbox.fd;
+
+ rc = init_flash_dev(&test.context);
+ assert(rc == 0);
+
+ rc = fallocate(test.flash.fd, 0, 0, test.context.mtd_info.size);
+ assert(rc == 0);
+
+ rc = fallocate(test.lpc.fd, 0, 0, test.context.mtd_info.size);
+ assert(rc == 0);
+
+ rc = __init_lpc_dev(&test.context, test.lpc.path);
+ assert(rc == 0);
+
+ rc = init_windows(&test.context);
+ assert(rc == 0);
+
+ return rc ? NULL : &test.context;
+}
+
+/* From ccan's container_of module, CC0 license */
+#define container_of(member_ptr, containing_type, member) \
+ ((containing_type *) \
+ ((char *)(member_ptr) \
+ - container_off(containing_type, member)) \
+ + check_types_match(*(member_ptr), ((containing_type *)0)->member))
+
+/* From ccan's container_of module, CC0 license */
+#define container_off(containing_type, member) \
+ offsetof(containing_type, member)
+
+/* From ccan's check_type module, CC0 license */
+#define check_type(expr, type) \
+ ((typeof(expr) *)0 != (type *)0)
+
+/* From ccan's check_type module, CC0 license */
+#define check_types_match(expr1, expr2) \
+ ((typeof(expr1) *)0 != (typeof(expr2) *)0)
+
+int mbox_set_mtd_data(struct mbox_context *context, const void *data,
+ size_t len)
+{
+ struct mbox_test_context *arg;
+ void *map;
+
+ /* Sanity check */
+ arg = container_of(context, struct mbox_test_context, context);
+ if (&test != arg)
+ return -1;
+
+ if (len > test.context.mtd_info.size)
+ return -2;
+
+ map = mmap(NULL, test.context.mtd_info.size, PROT_WRITE, MAP_SHARED,
+ test.flash.fd, 0);
+ assert(map != MAP_FAILED);
+ memcpy(map, data, len);
+ munmap(map, test.context.mtd_info.size);
+
+ return 0;
+}
+
+char *get_dev_mtd(void)
+{
+ return strdup(test.flash.path);
+}