mboxd: Update mboxd to implement protocol V2 and add dbus support

Version 2 of the mbox protocol contains a few changes such as:
 - All sizes are in block size
 - Adds an erase command
 - Adds new response codes
 - Adds new BMC events
 - Open windows commands now take a size directive

Update the mailbox daemon to support version 2 of the protocol which
includes implementing all of the V2 functionality. Also entirely refactor
the mboxd.c code to make it more modular improving readability and
maintainability.

At the same time improve the functionality by adding:
 - Multiple windows in the daemon (still only one active window) to cache
   flash contents
 - Implement a dbus interface to allow interaction with the daemon
 - Handle sigterm and sigint and terminate cleanly

The previous implementation utilised the entire reserved memory region.
Update the daemon so that on the command line the number of windows and
the size of each which the reserved memory region will be split into can
be specified. The reserved memory region is then divided between the
windows, however there can still only be one "active" window at a time.
The daemon uses these windows to cache the flash contents meaning the
flash doesn't have to be copied when the host requests access assuming
the daemon already has a copy.

A dbus interface is added so that commands can be sent to the daemon to
control it's operation from the bmc. These include suspending and resuming
the daemon to synchronise flash access, telling the daemon to point the lpc
mapping back to flash and telling the daemon when the flash has been
modified out from under it.

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Change-Id: I10be01a395c2bec437cf2c825fdd144580b60dbc

1 files changed, 192 insertions, 0 deletions

diff --git a/mboxd_lpc.c b/mboxd_lpc.c
new file mode 100644
index 0000000..42e4328
--- /dev/null
+++ b/mboxd_lpc.c
@@ -0,0 +1,192 @@
+/*
+ * Mailbox Daemon LPC Helpers
+ *
+ * Copyright 2016 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
+#include <assert.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <getopt.h>
+#include <limits.h>
+#include <poll.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <syslog.h>
+#include <signal.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <sys/timerfd.h>
+#include <sys/types.h>
+#include <time.h>
+#include <unistd.h>
+#include <inttypes.h>
+
+#include "mbox.h"
+#include "common.h"
+#include "mboxd_lpc.h"
+#include "mboxd_flash.h"
+#include <linux/aspeed-lpc-ctrl.h>
+
+#define LPC_CTRL_PATH		"/dev/aspeed-lpc-ctrl"
+
+int init_lpc_dev(struct mbox_context *context)
+{
+	struct aspeed_lpc_ctrl_mapping map = {
+		.window_type = ASPEED_LPC_CTRL_WINDOW_MEMORY,
+		.window_id = 0, /* There's only one */
+		.flags = 0,
+		.addr = 0,
+		.offset = 0,
+		.size = 0
+	};
+	int fd;
+
+	/* Open LPC Device */
+	MSG_OUT("Opening %s\n", LPC_CTRL_PATH);
+	fd = open(LPC_CTRL_PATH, O_RDWR | O_SYNC);
+	if (fd < 0) {
+		MSG_ERR("Couldn't open %s with flags O_RDWR: %s\n",
+			LPC_CTRL_PATH, strerror(errno));
+		return -errno;
+	}
+
+	context->fds[LPC_CTRL_FD].fd = fd;
+
+	/* Find Size of Reserved Memory Region */
+	MSG_OUT("Getting buffer size...\n");
+	if (ioctl(fd, ASPEED_LPC_CTRL_IOCTL_GET_SIZE, &map) < 0) {
+		MSG_ERR("Couldn't get lpc control buffer size: %s\n",
+			strerror(errno));
+		return -errno;
+	}
+
+	context->mem_size = map.size;
+	/* Map at the top of the 28-bit LPC firmware address space-0 */
+	context->lpc_base = 0x0FFFFFFF & -context->mem_size;
+	
+	/* mmap the Reserved Memory Region */
+	MSG_OUT("Mapping %s for %u\n", LPC_CTRL_PATH, context->mem_size);
+	context->mem = mmap(NULL, context->mem_size, PROT_READ | PROT_WRITE,
+				MAP_SHARED, fd, 0);
+	if (context->mem == MAP_FAILED) {
+		MSG_ERR("Didn't manage to mmap %s: %s\n", LPC_CTRL_PATH,
+			strerror(errno));
+		return -errno;
+	}
+
+	return 0;
+}
+
+void free_lpc_dev(struct mbox_context *context)
+{
+	if (context->mem) {
+		munmap(context->mem, context->mem_size);
+	}
+	close(context->fds[LPC_CTRL_FD].fd);
+}
+
+/*
+ * point_to_flash() - Point the lpc bus mapping to the actual flash device
+ * @context:	The mbox context pointer
+ *
+ * Return:	0 on success otherwise negative error code
+ */
+int point_to_flash(struct mbox_context *context)
+{
+	struct aspeed_lpc_ctrl_mapping map = {
+		.window_type = ASPEED_LPC_CTRL_WINDOW_FLASH,
+		.window_id = 0, /* Theres only one */
+		.flags = 0,
+		/*
+		 * The mask is because the top nibble is the host LPC FW space,
+		 * we want space 0.
+		 */
+		.addr = 0x0FFFFFFF & -context->flash_size,
+		.offset = 0,
+		.size = context->flash_size
+	};
+
+	if (context->state & MAPS_FLASH) {
+		return 0; /* LPC Bus already points to flash */
+	}
+	/* Don't let the host access flash while we're suspended */
+	if (context->state & STATE_SUSPENDED) {
+		MSG_ERR("Can't point lpc mapping to flash while suspended\n");
+		return -MBOX_R_PARAM_ERROR;
+	}
+
+	MSG_OUT("Pointing HOST LPC bus at the actual flash\n");
+	MSG_OUT("Assuming %dMB of flash: HOST LPC 0x%08x\n",
+		context->flash_size >> 20, map.addr);
+
+	if (ioctl(context->fds[LPC_CTRL_FD].fd, ASPEED_LPC_CTRL_IOCTL_MAP, &map)
+			== -1) {
+		MSG_ERR("Failed to point the LPC BUS at the actual flash: %s\n",
+			strerror(errno));
+		return -MBOX_R_SYSTEM_ERROR;
+	}
+
+	context->state = ACTIVE_MAPS_FLASH;
+	/*
+	 * Since the host now has access to the flash it can change it out from
+	 * under us
+	 */
+	return set_flash_bytemap(context, 0, context->flash_size, FLASH_DIRTY);
+}
+
+/*
+ * point_to_memory() - Point the lpc bus mapping to the reserved memory region
+ * @context:	The mbox context pointer
+ *
+ * Return:	0 on success otherwise negative error code
+ */
+int point_to_memory(struct mbox_context *context)
+{
+	struct aspeed_lpc_ctrl_mapping map = {
+		.window_type = ASPEED_LPC_CTRL_WINDOW_MEMORY,
+		.window_id = 0, /* There's only one */
+		.flags = 0,
+		.addr = context->lpc_base,
+		.offset = 0,
+		.size = context->mem_size
+	};
+
+	if (context->state & MAPS_MEM) {
+		return 0; /* LPC Bus already points to reserved memory area */
+	}
+
+	MSG_OUT("Pointing HOST LPC bus at memory region %p of size 0x%.8x\n",
+			context->mem, context->mem_size);
+	MSG_OUT("LPC address 0x%.8x\n", map.addr);
+
+	if (ioctl(context->fds[LPC_CTRL_FD].fd, ASPEED_LPC_CTRL_IOCTL_MAP,
+		  &map)) {
+		MSG_ERR("Failed to point the LPC BUS to memory: %s\n",
+			strerror(errno));
+		return -MBOX_R_SYSTEM_ERROR;
+	}
+
+	/* LPC now maps memory (keep suspended state) */
+	context->state = MAPS_MEM | (context->state & STATE_SUSPENDED);
+
+	return 0;
+}