Add DeviceData to bootloaders

same vein as bootdata but for devices that need to pass info back to a
running firmware

Change-Id: I0cdcdc0475804dfbbee415ab487104ae8fc8ac69

firmware/common/devicedata.c

@@ -0,0 +1,88 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ *
+ * Copyright (C) 2024 by William Wilgus
+ *
+ * This program 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 2
+ * of the License, or (at your option) any later version.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+
+#include "devicedata.h"
+#include "crc32.h"
+#include <stddef.h>
+#include <string.h>
+#include "debug.h"
+
+#ifndef BOOTLOADER
+void verify_device_data(void) INIT_ATTR;
+void verify_device_data(void)
+{
+    DEBUGF("%s", __func__);
+    /* verify payload with checksum */
+    uint32_t crc = crc_32(device_data.payload, device_data.length, 0xffffffff);
+    if (crc == device_data.crc)
+        return; /* return if data is valid */
+
+    /* Write the default if data is invalid */
+    memset(device_data.payload, 0xff, DEVICE_DATA_PAYLOAD_SIZE); /* Invalid data */
+    device_data.length = DEVICE_DATA_PAYLOAD_SIZE;
+    device_data.crc = crc_32(device_data.payload, device_data.length, 0xffffffff);
+
+}
+
+/******************************************************************************/
+#endif /* ndef BOOTLOADER ******************************************************/
+/******************************************************************************/
+
+#if defined(HAVE_DEVICEDATA)
+void  __attribute__((weak)) fill_devicedata(struct device_data_t *data)
+{
+    memset(data->payload, 0xff, data->length);
+}
+#endif
+
+/* Write bootdata into location in FIRMWARE marked by magic header
+ * Assumes buffer is already loaded with the firmware image
+ * We just need to find the location and write data into the
+ * payload region along with the crc for later verification and use.
+ * Returns payload len on success,
+ * On error returns false
+ */
+bool write_devicedata(unsigned char* buf, int len)
+{
+    int search_len = MIN(len, DEVICE_DATA_SEARCH_SIZE) - sizeof(struct device_data_t);
+
+    /* search for decvice data header prior to search_len */
+    for(int i = 0; i < search_len; i++)
+    {
+        struct device_data_t *data = (struct device_data_t *)&buf[i];
+        if (data->magic[0] != DEVICE_DATA_MAGIC0 ||
+            data->magic[1] != DEVICE_DATA_MAGIC1)
+            continue;
+
+        /* Ignore it if the length extends past the end of the buffer. */
+        int data_len = offsetof(struct device_data_t, payload) + data->length;
+        if (i + data_len > len)
+            continue;
+
+        fill_devicedata(data);
+
+        /* Calculate payload CRC */
+        data->crc = crc_32(data->payload, data->length, 0xffffffff);
+        return true;
+    }
+
+    return false;
+}
+

firmware/common/rb-loader.c

@@ -30,6 +30,9 @@
 #include "multiboot.h"
 #endif
 
+#ifdef HAVE_DEVICEDATA
+#include "devicedata.h"
+#endif
 /* loads a firmware file from supplied filename
  * file opened, checks firmware size and checksum
  * if no error, firmware loaded to supplied buffer
@@ -118,7 +121,6 @@ int load_firmware(unsigned char* buf, const char* firmware, int buffer_size)
             /* if ret is valid breaks from loop to continue loading */
         }
 #endif
-
         if (ret < 0) /* Check default volume, no valid firmware file loaded yet */
         {
             /* First check in BOOTDIR */
@@ -141,5 +143,9 @@ int load_firmware(unsigned char* buf, const char* firmware, int buffer_size)
     else /* full path passed ROLO etc.*/
         ret = load_firmware_filename(buf, firmware, buffer_size);
 
+#ifdef HAVE_DEVICEDATA
+        write_devicedata(buf, ret);
+#endif
+
     return ret;
 }