flash/nor: Allow CFI memory read/write functions be overriden

Add possibility to supply custom CFI memory accessors via cfi_info
and override the default memory-mapped ones.

Change-Id: I1b6bc1db69fc33e8cdef96c41742c40e6d8917e9
Signed-off-by: Marek Vasut <marek.vasut@gmail.com>
Reviewed-on: http://openocd.zylin.com/5147
Tested-by: jenkins
Reviewed-by: Tomas Vanek <vanekt@fbl.cz>

src/flash/nor/cfi.c

@@ -134,15 +134,25 @@ static inline uint32_t flash_address(struct flash_bank *bank, int sector, uint32
 static int cfi_target_write_memory(struct flash_bank *bank, target_addr_t addr,
 				   uint32_t count, const uint8_t *buffer)
 {
-	return target_write_memory(bank->target, addr, bank->bus_width,
-				   count, buffer);
+	struct cfi_flash_bank *cfi_info = bank->driver_priv;
+	if (cfi_info->write_mem) {
+		return cfi_info->write_mem(bank, addr, count, buffer);
+	} else {
+		return target_write_memory(bank->target, addr, bank->bus_width,
+					   count, buffer);
+	}
 }
 
 static int cfi_target_read_memory(struct flash_bank *bank, target_addr_t addr,
 				  uint32_t count, uint8_t *buffer)
 {
-	return target_read_memory(bank->target, addr, bank->bus_width,
-				  count, buffer);
+	struct cfi_flash_bank *cfi_info = bank->driver_priv;
+	if (cfi_info->read_mem) {
+		return cfi_info->read_mem(bank, addr, count, buffer);
+	} else {
+		return target_read_memory(bank->target, addr, bank->bus_width,
+					  count, buffer);
+	}
 }
 
 static void cfi_command(struct flash_bank *bank, uint8_t cmd, uint8_t *cmd_buf)

src/flash/nor/cfi.h

@@ -73,6 +73,12 @@ struct cfi_flash_bank {
 	unsigned buf_write_timeout;
 	unsigned block_erase_timeout;
 	unsigned chip_erase_timeout;
+
+	/* memory accessors */
+	int (*write_mem)(struct flash_bank *bank, target_addr_t addr,
+			 uint32_t count, const uint8_t *buffer);
+	int (*read_mem)(struct flash_bank *bank, target_addr_t addr,
+			uint32_t count, uint8_t *buffer);
 };
 
 /* Intel primary extended query table