nrf51: verify that UICR needs erasing before triggering an error about it

If the UICR is already empty, there's no reason to return an error
just because it can't be erased again.  This happens, for example,
when flashing UICR from GDB after a "monitor nrf51 mass_erase".

Change-Id: Ia6d28c43189205fb5a7120b1c7312e45eb32edb7
Signed-off-by: Jim Paris <jim@jtan.com>
Reviewed-on: http://openocd.zylin.com/2363
Tested-by: jenkins
Reviewed-by: Spencer Oliver <spen@spen-soft.co.uk>

diff --git a/src/flash/nor/nrf51.c b/src/flash/nor/nrf51.c
index 8b6a57fb8db73e6c2e253d2e6c605917c6ca77da..bfa199a2ffc415a7b8c5e010427b80b60ff833de 100644 (file)
--- a/src/flash/nor/nrf51.c
+++ b/src/flash/nor/nrf51.c
@@ -581,6 +581,12 @@ static int nrf51_erase_page(struct flash_bank *bank,
                }
 
                if ((ppfc & 0xFF) == 0xFF) {
+                       /* We can't erase the UICR.  Double-check to
+                          see if it's already erased before complaining. */
+                       default_flash_blank_check(bank);
+                       if (sector->is_erased == 1)
+                               return ERROR_OK;
+
                        LOG_ERROR("The chip was not pre-programmed with SoftDevice stack and UICR cannot be erased separately. Please issue mass erase before trying to write to this region");
                        return ERROR_FAIL;
                };