Enable boot from SD for Sansa e200

Change-Id: I0940f2cd5fc914d6d5061b5798b1a636009649b7

5 files changed, 193 insertions, 15 deletions

diff --git a/firmware/export/config/sansae200.h b/firmware/export/config/sansae200.h
index e03784a204..59e531241f 100644
--- a/firmware/export/config/sansae200.h
+++ b/firmware/export/config/sansae200.h
@@ -8,6 +8,12 @@
 
 #define HW_SAMPR_CAPS       (SAMPR_CAP_48 | SAMPR_CAP_44 | SAMPR_CAP_32)
 
+/* Define if boot data from bootloader has been enabled for the target */
+#define HAVE_BOOTDATA
+
+/* define boot redirect file name allows booting from external drives */
+#define BOOT_REDIR "rockbox_main.e200"
+
 /* define this if you have recording possibility */
 #define HAVE_RECORDING
 
@@ -178,11 +184,10 @@
 #define FIRMWARE_OFFSET_FILE_CRC    0x0
 #define FIRMWARE_OFFSET_FILE_DATA   0x8
 
-#ifndef BOOTLOADER
 #define HAVE_MULTIDRIVE
+//#define HAVE_MULTIVOLUME
 #define NUM_DRIVES 2
-#define HAVE_HOTSWAP
-#endif
+#define HAVE_HOTSWAP /* required to access sd from bootloader */
 
 /* USB On-the-go */
 #define CONFIG_USBOTG USBOTG_ARC
diff --git a/firmware/export/mi4-loader.h b/firmware/export/mi4-loader.h
index 1b4a4b93b2..f66164ec2c 100644
--- a/firmware/export/mi4-loader.h
+++ b/firmware/export/mi4-loader.h
@@ -49,3 +49,22 @@ struct tea_key {
 
 int load_mi4(unsigned char* buf, const char* firmware, unsigned int buffer_size);
 const char *mi4_strerror(int8_t errno);
+
+#ifdef HAVE_MULTIBOOT /* defined by config.h */
+/* Check in root of this <volume> for rockbox_main.<playername>
+ * if this file empty or there is a single slash '/'
+ * buf = '<volume#>/<rootdir>/<firmware(name)>\0'
+ * If instead '/<*DIRECTORY*>' is supplied
+ * addpath will be set to this DIRECTORY buf =
+ * '/<volume#>/addpath/<rootdir>/<firmware(name)>\0'
+ * On error returns Negative number or 0
+ * On success returns bytes from snprintf
+ * and generated path will be placed in buf
+ * note: if supplied buffer is too small return will be
+ * the number of bytes that would have been written
+ */
+
+/* TODO needs mapped back to debug_menu if root redirect ever becomes a reality */
+int get_redirect_dir(char* buf, int buffer_size, int volume,
+                     const char* rootdir, const char* firmware);
+#endif
diff --git a/firmware/rolo.c b/firmware/rolo.c
index 769346662b..de19c8e925 100644
--- a/firmware/rolo.c
+++ b/firmware/rolo.c
@@ -42,6 +42,11 @@
 #if defined(MI4_FORMAT)
 #include "crc32-mi4.h"
 #include "mi4-loader.h"
+#if defined(HAVE_BOOTDATA) && !defined(SIMULATOR)
+#include "bootdata.h"
+#include "crc32.h"
+extern  int write_bootdata(unsigned char* buf, int len, unsigned int boot_volume); /*mi4-loader.c*/    
+#endif
 #define LOAD_FIRMWARE(a,b,c) load_mi4(a,b,c)
 #elif defined(RKW_FORMAT)
 #include "rkw-loader.h"
diff --git a/firmware/target/arm/pp/crt0-pp.S b/firmware/target/arm/pp/crt0-pp.S
index 4e7621ecc8..3b78f57eea 100644
--- a/firmware/target/arm/pp/crt0-pp.S
+++ b/firmware/target/arm/pp/crt0-pp.S
@@ -21,6 +21,10 @@
 #include "config.h"
 #include "cpu.h"
 
+#if defined(HAVE_BOOTDATA) && !defined(BOOTLOADER)
+#include "bootdata.h"
+#endif
+
     .section .init.text,"ax",%progbits
 
     .global    start
@@ -402,6 +406,11 @@ prefetch_abort_handler:
     mov    r1, #1
     b      UIE
 
+#if defined(HAVE_BOOTDATA) && !defined(BOOTLOADER)
+/* boot data structure */
+put_boot_data_here
+#endif
+
 /* Align stacks to cache line boundary */
     .balign 32
 
diff --git a/firmware/target/arm/pp/mi4-loader.c b/firmware/target/arm/pp/mi4-loader.c
index c465b898b4..31b0065888 100644
--- a/firmware/target/arm/pp/mi4-loader.c
+++ b/firmware/target/arm/pp/mi4-loader.c
@@ -7,6 +7,7 @@
  *                     \/            \/     \/    \/            \/
  *
  * Copyright (C) 2006 by Barry Wardell
+ * Copyright (C) 2020 by William Wilgus [MULTIBOOT]
  *
  * Based on Rockbox iriver bootloader by Linus Nielsen Feltzing
  * and the ipodlinux bootloader by Daniel Palffy and Bernard Leach
@@ -28,6 +29,97 @@
 #include "loader_strerror.h"
 #include "crc32-mi4.h"
 #include "file.h"
+#if defined(HAVE_BOOTDATA)
+#include "system.h"
+#include "bootdata.h"
+#include "crc32.h"
+
+/* 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 EKEY_NOT_FOUND
+ */
+int write_bootdata(unsigned char* buf, int len, unsigned int boot_volume)
+{
+    struct boot_data_t bl_boot_data;
+    struct boot_data_t *fw_boot_data = NULL;
+    int search_len = MIN(len, BOOT_DATA_SEARCH_SIZE) - sizeof(struct boot_data_t);
+    int payload_len = EKEY_NOT_FOUND;
+
+    /* search for boot data header prior to search_len */
+    for(int i = 0;i < search_len;i++)
+    {
+        fw_boot_data = (struct boot_data_t*) &buf[i];
+        if (fw_boot_data->magic[0] != BOOT_DATA_MAGIC0 ||
+            fw_boot_data->magic[1] != BOOT_DATA_MAGIC1)
+            continue;
+
+        memset(&bl_boot_data.payload, 0, BOOT_DATA_PAYLOAD_SIZE);
+        bl_boot_data.boot_volume = boot_volume;
+
+        memset(fw_boot_data->payload, 0, fw_boot_data->length);
+        /* determine maximum bytes we can write to firmware
+           BOOT_DATA_PAYLOAD_SIZE is the size the bootloader expects */
+        payload_len = MIN(BOOT_DATA_PAYLOAD_SIZE, fw_boot_data->length);
+        fw_boot_data->length = payload_len;
+        /* copy data to FIRMWARE bootdata struct */
+        memcpy(fw_boot_data->payload, &bl_boot_data.payload, payload_len);
+        /* crc will be used within the firmware to check validity of bootdata */
+        fw_boot_data->crc = crc_32(fw_boot_data->payload, payload_len, 0xffffffff);
+        break;
+
+    }
+    return payload_len;
+}
+#endif /* HAVE_BOOTDATA */
+
+#ifdef HAVE_MULTIBOOT /* defined by config.h */
+/* Check in root of this <volume> for rockbox_main.<playername>
+ * if this file empty or there is a single slash '/'
+ * buf = '<volume#>/<rootdir>/<firmware(name)>\0'
+ * If instead '/<*DIRECTORY*>' is supplied
+ * addpath will be set to this DIRECTORY buf =
+ * '/<volume#>/addpath/<rootdir>/<firmware(name)>\0'
+ * On error returns Negative number or 0
+ * On success returns bytes from snprintf
+ * and generated path will be placed in buf
+ * note: if supplied buffer is too small return will be
+ * the number of bytes that would have been written
+ */
+int get_redirect_dir(char* buf, int buffer_size, int volume,
+                     const char* rootdir, const char* firmware)
+{
+    int fd;
+    int f_offset;
+    char add_path[MAX_PATH];
+    /* Check in root of volume for rockbox_main.<playername> redirect */
+    snprintf(add_path, sizeof(add_path), "/<%d>/"BOOT_REDIR, volume);
+    fd = open(add_path, O_RDONLY);
+    if (fd < 0)
+        return EFILE_NOT_FOUND;
+
+    /*clear add_path for re-use*/
+    memset(add_path, 0, sizeof(add_path));
+    f_offset = read(fd, add_path,sizeof(add_path));
+    close(fd);
+
+    for(int i = f_offset - 1;i > 0; i--)
+    {
+        /* strip control chars < SPACE or all if path doesn't start with '/' */
+        if (add_path[i] < 0x20 || add_path[0] != '/')
+           add_path[i] = '\0';
+    }
+    /* if '/add_path' is specified in rockbox_main.<playername>
+       path is /<vol#>/add_path/rootdir/firmwarename
+       if add_path is empty or '/' is missing from beginning
+       path is /<vol#>/rootdir/firmwarename
+    */
+    return snprintf(buf, buffer_size, "/<%d>%s/%s/%s", volume, add_path,
+                                                        rootdir, firmware);
+}
+#endif /* HAVE_MULTIBOOT */
 
 static inline unsigned int le2int(unsigned char* buf)
 {
@@ -169,26 +261,20 @@ static int tea_find_key(struct mi4header_t *mi4header, unsigned char* buf)
     return key_found;
 }
 
-/* Load mi4 format firmware image */
-int load_mi4(unsigned char* buf,
-             const char* firmware,
-             unsigned int buffer_size)
+/* Load mi4 format firmware image from a FULLY QUALIFIED PATH */
+static int load_mi4_filename(unsigned char* buf,
+                                const char* filename,
+                               unsigned int buffer_size)
 {
     int fd;
     struct mi4header_t mi4header;
     int rc;
     unsigned long sum;
-    char filename[MAX_PATH];
 
-    snprintf(filename,sizeof(filename), BOOTDIR "/%s",firmware);
     fd = open(filename, O_RDONLY);
+
     if(fd < 0)
-    {
-        snprintf(filename,sizeof(filename),"/%s",firmware);
-        fd = open(filename, O_RDONLY);
-        if(fd < 0)
-            return EFILE_NOT_FOUND;
-    }
+        return EFILE_NOT_FOUND;
 
     read(fd, &mi4header, MI4_HEADER_SIZE);
 
@@ -235,3 +321,57 @@ int load_mi4(unsigned char* buf,
 
     return mi4header.mi4size - MI4_HEADER_SIZE;
 }
+
+/* Load mi4 format firmware image */
+int load_mi4(unsigned char* buf, const char* firmware, unsigned int buffer_size)
+{
+
+    int ret = EFILE_NOT_FOUND;
+    char filename[MAX_PATH+2];
+    /* only filename passed */
+    if (firmware[0] != '/')
+    {
+
+#ifdef HAVE_MULTIBOOT /* defined by config.h */
+        /* checks <volumes> highest index to lowest for redirect file
+         * 0 is the default boot volume, it is not checked here
+         * if found <volume>/rockbox_main.<playername> and firmware
+         * has a bootdata region this firmware will be loaded */
+        for (unsigned int i = NUM_VOLUMES - 1; i > 0 && ret < 0; i--)
+        {
+            if (get_redirect_dir(filename, sizeof(filename), i,
+                                 BOOTDIR, firmware) > 0)
+            {
+                ret = load_mi4_filename(buf, filename, buffer_size);
+            /* if firmware has no boot_data don't load from external drive */
+                if (write_bootdata(buf, ret, i) <= 0)
+                    ret = EKEY_NOT_FOUND;
+            }
+            /* 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 */
+            snprintf(filename, sizeof(filename), BOOTDIR "/%s",firmware);
+
+            ret = load_mi4_filename(buf, filename, buffer_size);
+
+            if (ret < 0)
+            {
+                /* Check in root dir */
+                snprintf(filename, sizeof(filename),"/%s",firmware);
+                ret = load_mi4_filename(buf, filename, buffer_size);
+            }
+#ifdef HAVE_BOOTDATA
+                /* 0 is the default boot volume */
+                write_bootdata(buf, ret, 0);
+#endif
+        }
+    }
+    else /* full path passed ROLO etc.*/
+        ret = load_mi4_filename(buf, firmware, buffer_size);
+
+    return ret;
+}