diff options
| author | Scott Allen <saydisp-git@yahoo.ca> | 2017-11-13 17:41:23 +0100 |
|---|---|---|
| committer | Martino Facchin <m.facchin@arduino.cc> | 2017-11-13 17:41:34 +0100 |
| commit | 7d4bca50419f2b2e57f92e9bec1cbbbe6d846fc1 (patch) | |
| tree | 9fe993a839ec06b4faeb3f920ab8031369385319 | |
| parent | 31223160ebfeb6aef21dded0572003eedb2b8fd1 (diff) | |
Always read key to check for new LUFA bootloader
Instead of checking for the NEW_LUFA_SIGNATURE once in program memory and then
setting a flag which is used for further checks, a function is used that always
checks program memory directly.
If a flag is used, there's a slight chance that its location in RAM could fall
on MAGIC_KEY_POS. In this case, an aborted USB auto-reset sequence may fail.
| -rw-r--r-- | cores/arduino/CDC.cpp | 9 | ||||
| -rw-r--r-- | cores/arduino/USBCore.cpp | 7 | ||||
| -rw-r--r-- | cores/arduino/USBCore.h | 3 |
3 files changed, 7 insertions, 12 deletions
diff --git a/cores/arduino/CDC.cpp b/cores/arduino/CDC.cpp index 39373f6..142f8f6 100644 --- a/cores/arduino/CDC.cpp +++ b/cores/arduino/CDC.cpp @@ -36,8 +36,6 @@ static volatile int32_t breakValue = -1; static u8 wdtcsr_save; -bool _updatedLUFAbootloader = false; - #define WEAK __attribute__ ((weak)) extern const CDCDescriptor _cdcInterface PROGMEM; @@ -59,6 +57,11 @@ const CDCDescriptor _cdcInterface = D_ENDPOINT(USB_ENDPOINT_IN (CDC_ENDPOINT_IN ),USB_ENDPOINT_TYPE_BULK,USB_EP_SIZE,0) }; +bool isLUFAbootloader() +{ + return pgm_read_word(FLASHEND - 1) == NEW_LUFA_SIGNATURE; +} + int CDC_GetInterface(u8* interfaceNum) { interfaceNum[0] += 2; // uses 2 @@ -108,7 +111,7 @@ bool CDC_Setup(USBSetup& setup) #if MAGIC_KEY_POS != (RAMEND-1) // For future boards save the key in the inproblematic RAMEND // Which is reserved for the main() return value (which will never return) - if (_updatedLUFAbootloader) { + if (isLUFAbootloader()) { // horray, we got a new bootloader! magic_key_pos = (RAMEND-1); } diff --git a/cores/arduino/USBCore.cpp b/cores/arduino/USBCore.cpp index e00fb02..81f689d 100644 --- a/cores/arduino/USBCore.cpp +++ b/cores/arduino/USBCore.cpp @@ -35,7 +35,6 @@ extern const u16 STRING_LANGUAGE[] PROGMEM; extern const u8 STRING_PRODUCT[] PROGMEM; extern const u8 STRING_MANUFACTURER[] PROGMEM; extern const DeviceDescriptor USB_DeviceDescriptorIAD PROGMEM; -extern bool _updatedLUFAbootloader; const u16 STRING_LANGUAGE[2] = { (3<<8) | (2+2), @@ -819,12 +818,6 @@ void USBDevice_::attach() UDIEN = (1<<EORSTE) | (1<<SOFE) | (1<<SUSPE); // Enable interrupts for EOR (End of Reset), SOF (start of frame) and SUSPEND TX_RX_LED_INIT; - -#if MAGIC_KEY_POS != (RAMEND-1) - if (pgm_read_word(FLASHEND - 1) == NEW_LUFA_SIGNATURE) { - _updatedLUFAbootloader = true; - } -#endif } void USBDevice_::detach() diff --git a/cores/arduino/USBCore.h b/cores/arduino/USBCore.h index 18560b6..4210ced 100644 --- a/cores/arduino/USBCore.h +++ b/cores/arduino/USBCore.h @@ -285,8 +285,7 @@ typedef struct // Old Caterina bootloader places the MAGIC key into unsafe RAM locations (it can be rewritten // by the running sketch before to actual reboot). // Newer bootloaders, recognizable by the LUFA "signature" at the end of the flash, can handle both -// the usafe and the safe location. Check once (in USBCore.cpp) if the bootloader in new, then set the global -// _updatedLUFAbootloader variable to true/false and place the magic key consequently +// the usafe and the safe location. #ifndef MAGIC_KEY #define MAGIC_KEY 0x7777 #endif |