From b9448bff169114f8263d11a5b452e141a48c0448 Mon Sep 17 00:00:00 2001
From: Karl Palsson <karlp@tweak.net.au>
Date: Mon, 23 Jul 2018 09:07:45 +0000
Subject: [PATCH] stm32l4: flash: fix page erase for second bank

l4 is pages, not sectors, so update apis to be consistent. (other
families use page/sector as defined in the reference manual)
Make sure that pages on the second bank can also be erased.  Use the
same style in use for f2/4/7 for sector numbers across banks.
---
 include/libopencm3/stm32/l4/flash.h |  4 ++--
 lib/stm32/l4/flash.c                | 18 +++++++-----------
 2 files changed, 9 insertions(+), 13 deletions(-)

diff --git a/include/libopencm3/stm32/l4/flash.h b/include/libopencm3/stm32/l4/flash.h
index be790d7d..b5442b6d 100644
--- a/include/libopencm3/stm32/l4/flash.h
+++ b/include/libopencm3/stm32/l4/flash.h
@@ -231,8 +231,8 @@ void flash_clear_status_flags(void);
 void flash_lock_option_bytes(void);
 void flash_program_word(uint32_t address, uint32_t data);
 void flash_program(uint32_t address, uint8_t *data, uint32_t len);
-void flash_erase_sector(uint8_t sector);
-void flash_erase_all_sectors(void);
+void flash_erase_page(uint32_t page);
+void flash_erase_all_pages(void);
 void flash_program_option_bytes(uint32_t data);
 
 END_DECLS
diff --git a/lib/stm32/l4/flash.c b/lib/stm32/l4/flash.c
index c3ec1f5e..e32142d5 100644
--- a/lib/stm32/l4/flash.c
+++ b/lib/stm32/l4/flash.c
@@ -146,32 +146,28 @@ void flash_program(uint32_t address, uint8_t *data, uint32_t len)
 	}
 }
 
-/** @brief Erase a Sector of FLASH
- * This performs all operations necessary to erase a sector in FLASH memory.
- * The page should be checked to ensure that it was properly erased. A sector
- * must first be fully erased before attempting to program it.
- * See the reference manual or the FLASH programming manual for details.
- * @param[in] sector (0 - 11 for some parts, 0-23 on others)
+/** @brief Erase a page of FLASH
+ * @param[in] page (0 - 255 for bank 1, 256-511 for bank 2)
  */
-void flash_erase_sector(uint8_t sector)
+void flash_erase_page(uint32_t page)
 {
 	flash_wait_for_last_operation();
 
-	FLASH_CR &= ~(FLASH_CR_PNB_MASK << FLASH_CR_PNB_SHIFT);
-	FLASH_CR |= (sector & FLASH_CR_PNB_MASK) << FLASH_CR_PNB_SHIFT;
+	/* page and bank are contiguous bits */
+	FLASH_CR &= ~((FLASH_CR_PNB_MASK << FLASH_CR_PNB_SHIFT) | FLASH_CR_BKER);
+	FLASH_CR |= page << FLASH_CR_PNB_SHIFT;
 	FLASH_CR |= FLASH_CR_PER;
 	FLASH_CR |= FLASH_CR_START;
 
 	flash_wait_for_last_operation();
 	FLASH_CR &= ~FLASH_CR_PER;
-	FLASH_CR &= ~(FLASH_CR_PNB_MASK << FLASH_CR_PNB_SHIFT);
 }
 
 /** @brief Erase All FLASH
  * This performs all operations necessary to erase all sectors in the FLASH
  * memory.
  */
-void flash_erase_all_sectors(void)
+void flash_erase_all_pages(void)
 {
 	flash_wait_for_last_operation();