fastboot: add preflash command to help with large downloads+flash
Without the partition name, the bootloader would have to store all
of the data until the next flash command, which potentially wastes
time.
To help the bootloader deal with the data more efficiently, we now
issue a flashing hint ("preflash:%s", partname).
"preflash:" is used to indicate that the following download
should ignore any previous "preflash:%s".
Bug: 6045918
Change-Id: I4e9708f64f28a4781bde14eb3714d36b281ec5be
diff --git a/fastboot/engine.c b/fastboot/engine.c
index 8d46991..4045759 100644
--- a/fastboot/engine.c
+++ b/fastboot/engine.c
@@ -76,6 +76,7 @@
#define OP_NOTICE 4
#define OP_FORMAT 5
#define OP_DOWNLOAD_SPARSE 6
+#define OP_COMMAND_IGNORE_FAIL 7
typedef struct Action Action;
@@ -374,6 +375,8 @@
// Following piece of code is similar to fb_queue_flash() but executes
// actions directly without queuing
+ snprintf(cmd, sizeof(cmd), "preflash:%s", partition);
+ fb_command(usb, cmd); /* Ignore status */
fprintf(stderr, "sending '%s' (%lli KB)...\n", partition, image.image_size/1024);
status = fb_download_data(usb, image.buffer, image.image_size);
if (status) goto cleanup;
@@ -402,6 +405,8 @@
{
Action *a;
+ a = queue_action(OP_COMMAND_IGNORE_FAIL, "preflash:%s", ptn);
+ a->msg = mkmsg("prep for '%s' (%d KB)", ptn, sz / 1024);
a = queue_action(OP_DOWNLOAD, "");
a->data = data;
a->size = sz;
@@ -415,6 +420,8 @@
{
Action *a;
+ a = queue_action(OP_COMMAND_IGNORE_FAIL, "preflash:%s", ptn);
+ a->msg = mkmsg("prep for sparse '%s' (%d KB)", ptn, sz / 1024);
a = queue_action(OP_DOWNLOAD_SPARSE, "");
a->data = s;
a->size = 0;
@@ -575,7 +582,9 @@
void fb_queue_download(const char *name, void *data, unsigned size)
{
- Action *a = queue_action(OP_DOWNLOAD, "");
+ Action *a;
+ a = queue_action(OP_COMMAND_IGNORE_FAIL, "preflash:");
+ a = queue_action(OP_DOWNLOAD, "");
a->data = data;
a->size = size;
a->msg = mkmsg("downloading '%s'", name);
@@ -614,6 +623,8 @@
status = fb_command(usb, a->cmd);
status = a->func(a, status, status ? fb_get_error() : "");
if (status) break;
+ } else if (a->op == OP_COMMAND_IGNORE_FAIL) {
+ fb_command(usb, a->cmd); /* Ignore status */
} else if (a->op == OP_QUERY) {
status = fb_command_response(usb, a->cmd, resp);
status = a->func(a, status, status ? fb_get_error() : resp);
diff --git a/fastboot/fastboot_protocol.txt b/fastboot/fastboot_protocol.txt
index 2248992..eede5d1 100644
--- a/fastboot/fastboot_protocol.txt
+++ b/fastboot/fastboot_protocol.txt
@@ -1,5 +1,5 @@
-FastBoot Version 0.4
+FastBoot Version 0.4++
----------------------
The fastboot protocol is a mechanism for communicating with bootloaders
@@ -67,10 +67,6 @@
Example Session
---------------
-Host: "getvar:version" request version variable
-
-Client: "OKAY0.4" return version "0.4"
-
Host: "getvar:nonexistant" request some undefined variable
Client: "OKAY" return value ""
@@ -123,6 +119,11 @@
"flash:%s" Write the previously downloaded image to the
named partition (if possible).
+ "preflash:%s" Optionally prepare for a download + flash.
+ E.g. flash directly during download. To deal with a
+ failed "flash" followed by a "boot", we send
+ "preflash:".
+
"erase:%s" Erase the indicated partition (clear to 0xFFs)
"boot" The previously downloaded data is a boot.img
@@ -140,7 +141,9 @@
"powerdown" Power off the device.
-
+* Note about sparse files
+ Large files can be split up using libsparse, and sent to the bootloader
+ as repeated chunks of "download:%08x" + "flash:%s".
Client Variables
----------------
@@ -151,9 +154,6 @@
The various currently defined names are:
- version Version of FastBoot protocol supported.
- It should be "0.3" for this document.
-
version-bootloader Version string for the Bootloader.
version-baseband Version string of the Baseband Software