use reserved bootloader get application start

the reserved bootloader size is set in the NVM user configuration
and allows to know the application start address (e.g. after the
bootloader)

Change-Id: I9dda27d6401caabb4a6470aa3fe9691f63097136

3 files changed, 18 insertions, 14 deletions

diff --git a/usb/class/dfu/device/dfudf.c b/usb/class/dfu/device/dfudf.c
index 41e235b..8232979 100644
--- a/usb/class/dfu/device/dfudf.c
+++ b/usb/class/dfu/device/dfudf.c
@@ -44,7 +44,7 @@ enum usb_dfu_status dfu_status = USB_DFU_STATUS_OK;
 
 uint8_t dfu_download_data[512];
 uint16_t dfu_download_length = 0;
-size_t dfu_download_progress = 0;
+size_t dfu_download_offset = 0;
 bool dfu_manifestation_complete = false;
 
 /**
@@ -215,7 +215,7 @@ static int32_t dfudf_out_req(uint8_t ep, struct usb_req *req, enum usb_ctrl_stag
 		to_return = usbdc_xfer(ep, NULL, 0, false); // send ACK
 		break;
 	case USB_DFU_ABORT: // abort current operation
-		dfu_download_progress = 0; // reset download progress
+		dfu_download_offset = 0; // reset download progress
 		dfu_state = USB_DFU_STATE_DFU_IDLE; // put back in idle state (nothing else to do)
 		to_return = usbdc_xfer(ep, NULL, 0, false); // send ACK
 		break;
@@ -246,7 +246,7 @@ static int32_t dfudf_out_req(uint8_t ep, struct usb_req *req, enum usb_ctrl_stag
 			if (USB_SETUP_STAGE == stage) { // there will be data to be flash
 				to_return = usbdc_xfer(ep, dfu_download_data, req->wLength, false); // send ack to the setup request to get the data
 			} else { // now there is data to be flashed
-				dfu_download_progress = req->wValue * sizeof(dfu_download_data); // remember which block to flash
+				dfu_download_offset = req->wValue * sizeof(dfu_download_data); // remember which block to flash
 				dfu_download_length = req->wLength; // remember the data size to be flash
 				dfu_state = USB_DFU_STATE_DFU_DNLOAD_SYNC; // go to sync state
 				to_return = usbdc_xfer(ep, NULL, 0, false); // ACK the data
diff --git a/usb/class/dfu/device/dfudf.h b/usb/class/dfu/device/dfudf.h
index a19b569..cee5845 100644
--- a/usb/class/dfu/device/dfudf.h
+++ b/usb/class/dfu/device/dfudf.h
@@ -49,8 +49,8 @@ extern enum usb_dfu_status dfu_status;
 extern uint8_t dfu_download_data[512];
 /** Length of downloaded data in bytes */
 extern uint16_t dfu_download_length;
-/** Progress of the already downloaded data in bytes */
-extern size_t dfu_download_progress;
+/** Offset of where the downloaded data should be flashed in bytes */
+extern size_t dfu_download_offset;
 /** If manifestation (firmware flash and check) is complete */
 extern bool dfu_manifestation_complete;
 
diff --git a/usb_start.c b/usb_start.c
index 0ce8aba..7503094 100644
--- a/usb_start.c
+++ b/usb_start.c
@@ -45,14 +45,6 @@ static const usb_dfu_func_desc_t* usb_dfu_func_desc = (usb_dfu_func_desc_t*)&usb
 /** Ctrl endpoint buffer */
 static uint8_t ctrl_buffer[64];
 
-/** Application address in the flash
- (
- *  It comes after the bootloader.
- *  The NVMCTRL allows to reserve space at the beginning of the flash for the bootloader, but only in multiples of 8192 bytes.
- *  The binary just with the USB stack already uses 8 kB, we reserve 16 kB for the bootloader (giving use a bit of margin for future fixes).
- */
-#define APPLICATION_ADDR (8192*2)
-
 /**
  * \brief USB DFU Init
  */
@@ -89,12 +81,24 @@ void usb_dfu(void)
 {
 	while (!dfudf_is_enabled()); // wait for DFU to be installed
 	gpio_set_pin_level(LED_SYSTEM, false); // switch LED on to indicate USB DFU stack is ready
+
+	uint32_t application_start = hri_nvmctrl_read_STATUS_BOOTPROT_bf(FLASH_0.dev.hw); // read BOOTPROT setting to get the bootloader size
+	ASSERT(application_start <= 15);
+	application_start = (15 - application_start) * 8192; // calculate bootloader size to know where we should write the application firmware
+	while (0 == application_start) { // no space has been reserved for the bootloader
+		// blink the LED to tell the user we don't know where the application starts
+		gpio_set_pin_level(LED_SYSTEM, false);
+		delay_ms(500);
+		gpio_set_pin_level(LED_SYSTEM, true);
+		delay_ms(500);
+	}
+
 	while (true) { // main DFU infinite loop
 		// run the second part of the USB DFU state machine handling non-USB aspects
 		if (USB_DFU_STATE_DFU_DNLOAD_SYNC == dfu_state || USB_DFU_STATE_DFU_DNBUSY == dfu_state) { // there is some data to be flashed
 			gpio_set_pin_level(LED_SYSTEM, true); // switch LED off to indicate we are flashing
 			if (dfu_download_length > 0) { // there is some data to be flashed
-				int32_t rc = flash_write(&FLASH_0, APPLICATION_ADDR + dfu_download_progress, dfu_download_data, dfu_download_length); // write downloaded data chunk to flash
+				int32_t rc = flash_write(&FLASH_0, application_start + dfu_download_offset, dfu_download_data, dfu_download_length); // write downloaded data chunk to flash
 				if (ERR_NONE == rc) {
 					dfu_state = USB_DFU_STATE_DFU_DNLOAD_IDLE; // indicate flashing this block has been completed
 				} else { // there has been a programming error