flash: New driver for XMC4xxx microcontroller family

This is a complete flash driver for the Infineon XMC4xxx family of
microcontrollers, based on the TMS570 driver by Andrey Yurovsky.
The driver attempts to discover the particular variant of MCU via a
combination of the SCU register (to determine if this is indeed an
XMC4xxx part) and the FLASH0_ID register (to determine the variant).
If this fails, the driver will not load.
The driver has been added to the README and documentation.

Tests:
* Hardware: XMC4500 (XMC4500_relax), XMC4200 (XMC4200 enterprise)
* SWD + JTAG
* Binary: 144k, 1M

Note:
* Flash protect only partly tested. These parts only allow the flash
  protection registers (UCB) to be written 4 times total, and my devkits
  have run out of uses (more on the way)

Future Work:
* User 1/2(permalock) locking support via custom command
* In-memory flash loader bootstrap (flashing is rather slow...)

Change-Id: I1d3345d5255d8de8dc4175cf987eb4a037a8cf7f
Signed-off-by: Jeff Ciesielski <jeffciesielski@gmail.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
Reviewed-on: http://openocd.zylin.com/2488
Tested-by: jenkins
Reviewed-by: Paul Fertser <fercerpav@gmail.com>

7 files changed, 1493 insertions, 2 deletions

diff --git a/README b/README
index 149eec5..d889d2f 100644
--- a/README
+++ b/README
@@ -130,7 +130,7 @@ ADUC702x, AT91SAM, AVR, CFI, DSP5680xx, EFM32, EM357, FM3, Kinetis,
 LPC8xx/LPC1xxx/LPC2xxx/LPC541xx, LPC2900, LPCSPIFI, Marvell QSPI,
 Milandr, NuMicro, PIC32mx, PSoC4, SiM3x, Stellaris, STM32, STMSMI,
 STR7x, STR9x, nRF51; NAND controllers of AT91SAM9, LPC3180, LPC32xx,
-i.MX31, MXC, NUC910, Orion/Kirkwood, S3C24xx, S3C6400.
+i.MX31, MXC, NUC910, Orion/Kirkwood, S3C24xx, S3C6400, XMC4xxx.
 
 
 ==================
diff --git a/contrib/loaders/erase_check/armv7m_0_erase_check.s b/contrib/loaders/erase_check/armv7m_0_erase_check.s
new file mode 100644
index 0000000..6b1e92a
--- /dev/null
+++ b/contrib/loaders/erase_check/armv7m_0_erase_check.s
@@ -0,0 +1,45 @@
+/***************************************************************************
+ *   Copyright (C) 2014 by Jeff Ciesielski                                 *
+ *   jeffciesielski@gmail.com                                              *
+ *                                                                         *
+ *   Based on the armv7m erase checker by:                                 *
+ *   Copyright (C) 2010 by Spencer Oliver                                  *
+ *   spen@spen-soft.co.uk                                                  *
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ *   This program is distributed in the hope that it will be useful,       *
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
+ *   GNU General Public License for more details.                          *
+ *                                                                         *
+ ***************************************************************************/
+
+/*
+	parameters:
+	r0 - address in
+	r1 - byte count
+	r2 - mask - result out
+*/
+
+	.text
+	.syntax unified
+	.cpu cortex-m0
+	.thumb
+	.thumb_func
+
+	.align	2
+
+loop:
+	ldrb	r3, [r0]
+	adds	r0, #1
+	orrs	r2, r2, r3
+	subs	r1, r1, #1
+	bne		loop
+end:
+	bkpt	#0
+
+	.end
diff --git a/doc/openocd.texi b/doc/openocd.texi
index 655a353..7ae2a3f 100644
--- a/doc/openocd.texi
+++ b/doc/openocd.texi
@@ -5777,6 +5777,22 @@ the flash clock.
 @end deffn
 @end deffn
 
+@deffn {Flash Driver} xmc4xxx
+All members of the XMC4xxx microcontroller family from Infineon.
+This driver does not require the chip and bus width to be specified.
+
+Some xmc4xxx-specific commands are defined:
+
+@deffn Command {xmc4xxx flash_password} bank_id passwd1 passwd2
+Saves flash protection passwords which are used to lock the user flash
+@end deffn
+
+@deffn Command {xmc4xxx flash_unprotect} bank_id user_level[0-1]
+Removes Flash write protection from the selected user bank
+@end deffn
+
+@end deffn
+
 @section NAND Flash Commands
 @cindex NAND
 
diff --git a/src/flash/nor/Makefile.am b/src/flash/nor/Makefile.am
index b065bb0..eabf6f9 100644
--- a/src/flash/nor/Makefile.am
+++ b/src/flash/nor/Makefile.am
@@ -49,7 +49,8 @@ NOR_DRIVERS = \
 	nrf51.c \
 	mrvlqspi.c \
 	psoc4.c \
-	sim3x.c
+	sim3x.c \
+	xmc4xxx.c
 
 noinst_HEADERS = \
 	core.h \
diff --git a/src/flash/nor/drivers.c b/src/flash/nor/drivers.c
index 4723cff..24bd306 100644
--- a/src/flash/nor/drivers.c
+++ b/src/flash/nor/drivers.c
@@ -62,6 +62,7 @@ extern struct flash_driver mrvlqspi_flash;
 extern struct flash_driver psoc4_flash;
 extern struct flash_driver sim3x_flash;
 extern struct flash_driver jtagspi_flash;
+extern struct flash_driver xmc4xxx_flash;
 
 /**
  * The list of built-in flash drivers.
@@ -108,6 +109,7 @@ static struct flash_driver *flash_drivers[] = {
 	&psoc4_flash,
 	&sim3x_flash,
 	&jtagspi_flash,
+	&xmc4xxx_flash,
 	NULL,
 };
 
diff --git a/src/flash/nor/xmc4xxx.c b/src/flash/nor/xmc4xxx.c
new file mode 100644
index 0000000..df288ff
--- /dev/null
+++ b/src/flash/nor/xmc4xxx.c
@@ -0,0 +1,1414 @@
+/**************************************************************************
+*   Copyright (C) 2015 Jeff Ciesielski <jeffciesielski@gmail.com>         *
+*                                                                         *
+*   This program is free software; you can redistribute it and/or modify  *
+*   it under the terms of the GNU General Public License as published by  *
+*   the Free Software Foundation; either version 2 of the License, or     *
+*   (at your option) any later version.                                   *
+*                                                                         *
+*   This program is distributed in the hope that it will be useful,       *
+*   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
+*   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
+*   GNU General Public License for more details.                          *
+*                                                                         *
+***************************************************************************/
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "imp.h"
+#include <helper/binarybuffer.h>
+#include <target/algorithm.h>
+#include <target/armv7m.h>
+
+/* Maximum number of sectors */
+#define MAX_XMC_SECTORS 12
+
+/* System control unit registers */
+#define SCU_REG_BASE 0x50004000
+
+#define SCU_ID_CHIP 0x04
+
+/* Base of the non-cached flash memory */
+#define PFLASH_BASE	0x0C000000
+
+/* User configuration block offsets */
+#define UCB0_BASE       0x00000000
+#define UCB1_BASE       0x00000400
+#define UCB2_BASE       0x00000800
+
+/* Flash register base */
+#define FLASH_REG_BASE 0x58000000
+
+/* PMU ID Registers */
+#define FLASH_REG_PMU_ID	(FLASH_REG_BASE | 0x0508)
+
+/* PMU Fields */
+#define PMU_MOD_REV_MASK	0xFF
+#define PMU_MOD_TYPE_MASK	0xFF00
+#define PMU_MOD_NO_MASK		0xFFFF0000
+
+/* Prefetch Config */
+#define FLASH_REG_PREF_PCON	(FLASH_REG_BASE | 0x4000)
+
+/* Prefetch Fields */
+#define PCON_IBYP	(1 << 0)
+#define PCON_IINV	(1 << 1)
+
+/* Flash ID Register */
+#define FLASH_REG_FLASH0_ID	(FLASH_REG_BASE | 0x2008)
+
+/* Flash Status Register */
+#define FLASH_REG_FLASH0_FSR	(FLASH_REG_BASE | 0x2010)
+
+#define FSR_PBUSY	(0)
+#define FSR_FABUSY	(1)
+#define FSR_PROG	(4)
+#define FSR_ERASE	(5)
+#define FSR_PFPAGE	(6)
+#define FSR_PFOPER	(8)
+#define FSR_SQER	(10)
+#define FSR_PROER	(11)
+#define FSR_PFSBER	(12)
+#define FSR_PFDBER	(14)
+#define FSR_PROIN	(16)
+#define FSR_RPROIN	(18)
+#define FSR_RPRODIS	(19)
+#define FSR_WPROIN0	(21)
+#define FSR_WPROIN1	(22)
+#define FSR_WPROIN2	(23)
+#define FSR_WPRODIS0	(25)
+#define FSR_WPRODIS1	(26)
+#define FSR_SLM		(28)
+#define FSR_VER		(31)
+
+#define FSR_PBUSY_MASK		(0x01 << FSR_PBUSY)
+#define FSR_FABUSY_MASK		(0x01 << FSR_FABUSY)
+#define FSR_PROG_MASK		(0x01 << FSR_PROG)
+#define FSR_ERASE_MASK		(0x01 << FSR_ERASE)
+#define FSR_PFPAGE_MASK		(0x01 << FSR_PFPAGE)
+#define FSR_PFOPER_MASK		(0x01 << FSR_PFOPER)
+#define FSR_SQER_MASK		(0x01 << FSR_SQER)
+#define FSR_PROER_MASK		(0x01 << FSR_PROER)
+#define FSR_PFSBER_MASK		(0x01 << FSR_PFSBER)
+#define FSR_PFDBER_MASK		(0x01 << FSR_PFDBER)
+#define FSR_PROIN_MASK		(0x01 << FSR_PROIN)
+#define FSR_RPROIN_MASK		(0x01 << FSR_RPROIN)
+#define FSR_RPRODIS_MASK	(0x01 << FSR_RPRODIS)
+#define FSR_WPROIN0_MASK	(0x01 << FSR_WPROIN0)
+#define FSR_WPROIN1_MASK	(0x01 << FSR_WPROIN1)
+#define FSR_WPROIN2_MASK	(0x01 << FSR_WPROIN2)
+#define FSR_WPRODIS0_MASK	(0x01 << FSR_WPRODIS0)
+#define FSR_WPRODIS1_MASK	(0x01 << FSR_WPRODIS1)
+#define FSR_SLM_MASK		(0x01 << FSR_SLM)
+#define FSR_VER_MASK		(0x01 << FSR_VER)
+
+/* Flash Config Register */
+#define FLASH_REG_FLASH0_FCON	(FLASH_REG_BASE | 0x2014)
+
+#define FCON_WSPFLASH           (0)
+#define FCON_WSECPF             (4)
+#define FCON_IDLE               (13)
+#define FCON_ESLDIS             (14)
+#define FCON_SLEEP              (15)
+#define FCON_RPA                (16)
+#define FCON_DCF                (17)
+#define FCON_DDF                (18)
+#define FCON_VOPERM             (24)
+#define FCON_SQERM              (25)
+#define FCON_PROERM             (26)
+#define FCON_PFSBERM            (27)
+#define FCON_PFDBERM            (29)
+#define FCON_EOBM               (31)
+
+#define FCON_WSPFLASH_MASK      (0x0f << FCON_WSPFLASH)
+#define FCON_WSECPF_MASK        (0x01 << FCON_WSECPF)
+#define FCON_IDLE_MASK          (0x01 << FCON_IDLE)
+#define FCON_ESLDIS_MASK        (0x01 << FCON_ESLDIS)
+#define FCON_SLEEP_MASK         (0x01 << FCON_SLEEP)
+#define FCON_RPA_MASK           (0x01 << FCON_RPA)
+#define FCON_DCF_MASK           (0x01 << FCON_DCF)
+#define FCON_DDF_MASK           (0x01 << FCON_DDF)
+#define FCON_VOPERM_MASK        (0x01 << FCON_VOPERM)
+#define FCON_SQERM_MASK         (0x01 << FCON_SQERM)
+#define FCON_PROERM_MASK        (0x01 << FCON_PROERM)
+#define FCON_PFSBERM_MASK       (0x01 << FCON_PFSBERM)
+#define FCON_PFDBERM_MASK       (0x01 << FCON_PFDBERM)
+#define FCON_EOBM_MASK          (0x01 << FCON_EOBM)
+
+/* Flash Margin Control Register */
+#define FLASH_REG_FLASH0_MARP	(FLASH_REG_BASE | 0x2018)
+
+#define MARP_MARGIN		(0)
+#define MARP_TRAPDIS		(15)
+
+#define MARP_MARGIN_MASK        (0x0f << MARP_MARGIN)
+#define MARP_TRAPDIS_MASK       (0x01 << MARP_TRAPDIS)
+
+/* Flash Protection Registers */
+#define FLASH_REG_FLASH0_PROCON0	(FLASH_REG_BASE | 0x2020)
+#define FLASH_REG_FLASH0_PROCON1	(FLASH_REG_BASE | 0x2024)
+#define FLASH_REG_FLASH0_PROCON2	(FLASH_REG_BASE | 0x2028)
+
+#define PROCON_S0L             (0)
+#define PROCON_S1L             (1)
+#define PROCON_S2L             (2)
+#define PROCON_S3L             (3)
+#define PROCON_S4L             (4)
+#define PROCON_S5L             (5)
+#define PROCON_S6L             (6)
+#define PROCON_S7L             (7)
+#define PROCON_S8L             (8)
+#define PROCON_S9L             (9)
+#define PROCON_S10_S11L        (10)
+#define PROCON_RPRO            (15)
+
+#define PROCON_S0L_MASK        (0x01 << PROCON_S0L)
+#define PROCON_S1L_MASK        (0x01 << PROCON_S1L)
+#define PROCON_S2L_MASK        (0x01 << PROCON_S2L)
+#define PROCON_S3L_MASK        (0x01 << PROCON_S3L)
+#define PROCON_S4L_MASK        (0x01 << PROCON_S4L)
+#define PROCON_S5L_MASK        (0x01 << PROCON_S5L)
+#define PROCON_S6L_MASK        (0x01 << PROCON_S6L)
+#define PROCON_S7L_MASK        (0x01 << PROCON_S7L)
+#define PROCON_S8L_MASK        (0x01 << PROCON_S8L)
+#define PROCON_S9L_MASK        (0x01 << PROCON_S9L)
+#define PROCON_S10_S11L_MASK   (0x01 << PROCON_S10_S11L)
+#define PROCON_RPRO_MASK       (0x01 << PROCON_RPRO)
+
+#define FLASH_PROTECT_CONFIRMATION_CODE 0x8AFE15C3
+
+/* Flash controller configuration values */
+#define FLASH_ID_XMC4500        0xA2
+#define FLASH_ID_XMC4100_4200   0x9C
+#define FLASH_ID_XMC4400        0x9F
+
+/* Timeouts */
+#define FLASH_OP_TIMEOUT 5000
+
+/* Flash commands (write/erase/protect) are performed using special
+ * command sequences that are written to magic addresses in the flash controller */
+/* Command sequence addresses.  See reference manual, section 8: Flash Command Sequences */
+#define FLASH_CMD_ERASE_1 0x0C005554
+#define FLASH_CMD_ERASE_2 0x0C00AAA8
+#define FLASH_CMD_ERASE_3 FLASH_CMD_ERASE_1
+#define FLASH_CMD_ERASE_4 FLASH_CMD_ERASE_1
+#define FLASH_CMD_ERASE_5 FLASH_CMD_ERASE_2
+/* ERASE_6 is the sector base address */
+
+#define FLASH_CMD_CLEAR_STATUS FLASH_CMD_ERASE_1
+
+#define FLASH_CMD_ENTER_PAGEMODE FLASH_CMD_ERASE_1
+
+#define FLASH_CMD_LOAD_PAGE_1 0x0C0055F0
+#define FLASH_CMD_LOAD_PAGE_2 0x0C0055F4
+
+#define FLASH_CMD_WRITE_PAGE_1 FLASH_CMD_ERASE_1
+#define FLASH_CMD_WRITE_PAGE_2 FLASH_CMD_ERASE_2
+#define FLASH_CMD_WRITE_PAGE_3 FLASH_CMD_ERASE_1
+/* WRITE_PAGE_4 is the page base address */
+
+#define FLASH_CMD_TEMP_UNPROT_1 FLASH_CMD_ERASE_1
+#define FLASH_CMD_TEMP_UNPROT_2 FLASH_CMD_ERASE_2
+#define FLASH_CMD_TEMP_UNPROT_3 0x0C00553C
+#define FLASH_CMD_TEMP_UNPROT_4 FLASH_CMD_ERASE_2
+#define FLASH_CMD_TEMP_UNPROT_5 FLASH_CMD_ERASE_2
+#define FLASH_CMD_TEMP_UNPROT_6 0x0C005558
+
+struct xmc4xxx_flash_bank {
+	bool probed;
+
+	/* We need the flash controller ID to choose the sector layout */
+	uint32_t fcon_id;
+
+	/* Passwords used for protection operations */
+	uint32_t pw1;
+	uint32_t pw2;
+	bool pw_set;
+
+	/* Protection flags */
+	bool read_protected;
+
+	bool write_prot_otp[MAX_XMC_SECTORS];
+};
+
+struct xmc4xxx_command_seq {
+	uint32_t address;
+	uint32_t magic;
+};
+
+/* Sector capacities.  See section 8 of xmc4x00_rm */
+static unsigned int sector_capacity_8[] = {
+	16, 16, 16, 16, 16, 16, 16, 128
+};
+
+static unsigned int sector_capacity_9[] = {
+	16, 16, 16, 16, 16, 16, 16, 128, 256
+};
+
+static unsigned int sector_capacity_12[] = {
+	16, 16, 16, 16, 16, 16, 16, 16, 128, 256, 256, 256
+};
+
+static int xmc4xxx_write_command_sequence(struct flash_bank *bank,
+					 struct xmc4xxx_command_seq *seq,
+					 int seq_len)
+{
+	int res = ERROR_OK;
+
+	for (int i = 0; i < seq_len; i++) {
+		res = target_write_u32(bank->target, seq[i].address,
+				       seq[i].magic);
+		if (res != ERROR_OK)
+			return res;
+	}
+
+	return ERROR_OK;
+}
+
+static int xmc4xxx_load_bank_layout(struct flash_bank *bank)
+{
+	unsigned int *capacity = NULL;
+
+	/* At this point, we know which flash controller ID we're
+	 * talking to and simply need to fill out the bank structure accordingly */
+	LOG_DEBUG("%d sectors", bank->num_sectors);
+
+	switch (bank->num_sectors) {
+	case 8:
+		capacity = sector_capacity_8;
+		break;
+	case 9:
+		capacity = sector_capacity_9;
+		break;
+	case 12:
+		capacity = sector_capacity_12;
+		break;
+	default:
+		LOG_ERROR("Unexpected number of sectors, %d\n",
+			  bank->num_sectors);
+		return ERROR_FAIL;
+	}
+
+	/* This looks like a bank that we understand, now we know the
+	 * corresponding sector capacities and we can add those up into the
+	 * bank size. */
+	uint32_t total_offset = 0;
+	bank->sectors = calloc(bank->num_sectors,
+			       sizeof(struct flash_sector));
+	for (int i = 0; i < bank->num_sectors; i++) {
+		bank->sectors[i].size = capacity[i] * 1024;
+		bank->sectors[i].offset = total_offset;
+		bank->sectors[i].is_erased = -1;
+		bank->sectors[i].is_protected = -1;
+
+		bank->size += bank->sectors[i].size;
+		LOG_DEBUG("\t%d: %uk", i, capacity[i]);
+		total_offset += bank->sectors[i].size;
+	}
+
+	/* This part doesn't follow the typical standard of 0xff
+	 * being the default padding value.*/
+	bank->default_padded_value = 0x00;
+
+	return ERROR_OK;
+}
+
+static int xmc4xxx_probe(struct flash_bank *bank)
+{
+	int res;
+	uint32_t devid, config;
+	struct xmc4xxx_flash_bank *fb = bank->driver_priv;
+	uint8_t flash_id;
+
+	if (fb->probed)
+		return ERROR_OK;
+
+	/* It's not possible for the DAP to access the OTP locations needed for
+	 * probing the part info and Flash geometry so we require that the target
+	 * be halted before proceeding. */
+	if (bank->target->state != TARGET_HALTED) {
+		LOG_WARNING("Cannot communicate... target not halted.");
+		return ERROR_TARGET_NOT_HALTED;
+	}
+
+	/* The SCU registers contain the ID of the chip */
+	res = target_read_u32(bank->target, SCU_REG_BASE + SCU_ID_CHIP, &devid);
+	if (res != ERROR_OK) {
+		LOG_ERROR("Cannot read device identification register.");
+		return res;
+	}
+
+	/* Make sure this is a XMC4000 family device */
+	if ((devid & 0xF0000) != 0x40000) {
+		LOG_ERROR("Platform ID doesn't match XMC4xxx: 0x%08" PRIx32, devid);
+		return ERROR_FAIL;
+	}
+
+	LOG_DEBUG("Found XMC4xxx with devid: 0x%08" PRIx32, devid);
+
+	/* Now sanity-check the Flash controller itself. */
+	res = target_read_u32(bank->target, FLASH_REG_FLASH0_ID,
+			&config);
+	if (res != ERROR_OK) {
+		LOG_ERROR("Cannot read Flash bank configuration.");
+		return res;
+	}
+	flash_id = (config & 0xff0000) >> 16;
+
+	/* The Flash configuration register is our only means of
+	 * determining the sector layout. We need to make sure that
+	 * we understand the type of controller we're dealing with */
+	switch (flash_id) {
+	case FLASH_ID_XMC4100_4200:
+		bank->num_sectors = 8;
+		LOG_DEBUG("XMC4xxx: XMC4100/4200 detected.");
+		break;
+	case FLASH_ID_XMC4400:
+		bank->num_sectors = 9;
+		LOG_DEBUG("XMC4xxx: XMC4400 detected.");
+		break;
+	case FLASH_ID_XMC4500:
+		bank->num_sectors = 12;
+		LOG_DEBUG("XMC4xxx: XMC4500 detected.");
+		break;
+	default:
+		LOG_ERROR("XMC4xxx: Unexpected flash ID. got %02" PRIx8,
+			  flash_id);
+		return ERROR_FAIL;
+	}
+
+	/* Retrieve information about the particular bank we're probing and fill in
+	 * the bank structure accordingly. */
+	res = xmc4xxx_load_bank_layout(bank);
+	if (res == ERROR_OK) {
+		/* We're done */
+		fb->probed = true;
+	} else {
+		LOG_ERROR("Unable to load bank information.");
+		return ERROR_FAIL;
+	}
+
+	return ERROR_OK;
+}
+
+static int xmc4xxx_get_sector_start_addr(struct flash_bank *bank,
+					 int sector, uint32_t *ret_addr)
+{
+	/* Make sure we understand this sector */
+	if (sector > bank->num_sectors)
+		return ERROR_FAIL;
+
+	*ret_addr = bank->base + bank->sectors[sector].offset;
+
+	return ERROR_OK;
+
+}
+
+static int xmc4xxx_clear_flash_status(struct flash_bank *bank)
+{
+	int res;
+	/* TODO: Do we need to check for sequence error? */
+	LOG_INFO("Clearing flash status");
+	res = target_write_u32(bank->target, FLASH_CMD_CLEAR_STATUS,
+			       0xF5);
+	if (res != ERROR_OK) {
+		LOG_ERROR("Unable to write erase command sequence");
+		return res;
+	}
+
+	return ERROR_OK;
+}
+
+static int xmc4xxx_get_flash_status(struct flash_bank *bank, uint32_t *status)
+{
+	int res;
+
+	res = target_read_u32(bank->target, FLASH_REG_FLASH0_FSR, status);
+
+	if (res != ERROR_OK)
+		LOG_ERROR("Cannot read flash status register.");
+
+	return res;
+}
+
+static int xmc4xxx_wait_status_busy(struct flash_bank *bank, int timeout)
+{
+	int res;
+	uint32_t status;
+
+	res = xmc4xxx_get_flash_status(bank, &status);
+	if (res != ERROR_OK)
+		return res;
+
+	/* While the flash controller is busy, wait */
+	while (status & FSR_PBUSY_MASK) {
+		res = xmc4xxx_get_flash_status(bank, &status);
+		if (res != ERROR_OK)
+			return res;
+
+		if (timeout-- <= 0) {
+			LOG_ERROR("Timed out waiting for flash");
+			return ERROR_FAIL;
+		}
+		alive_sleep(1);
+		keep_alive();
+	}
+
+	if (status & FSR_PROER_MASK) {
+		LOG_ERROR("XMC4xxx flash protected");
+		res = ERROR_FAIL;
+	}
+
+	return res;
+}
+
+static int xmc4xxx_erase_sector(struct flash_bank *bank, uint32_t address,
+				bool user_config)
+{
+	int res;
+	uint32_t status;
+
+	/* See reference manual table 8.4: Command Sequences for Flash Control */
+	struct xmc4xxx_command_seq erase_cmd_seq[6] = {
+		{FLASH_CMD_ERASE_1, 0xAA},
+		{FLASH_CMD_ERASE_2, 0x55},
+		{FLASH_CMD_ERASE_3, 0x80},
+		{FLASH_CMD_ERASE_4, 0xAA},
+		{FLASH_CMD_ERASE_5, 0x55},
+		{0xFF,              0xFF} /* Needs filled in */
+	};
+
+	/* We need to fill in the base address of the sector we'll be
+	 * erasing, as well as the magic code that determines whether
+	 * this is a standard flash sector or a user configuration block */
+
+	erase_cmd_seq[5].address = address;
+	if (user_config) {
+		/* Removing flash protection requires the addition of
+		 * the base address */
+		erase_cmd_seq[5].address += bank->base;
+		erase_cmd_seq[5].magic = 0xC0;
+	} else {
+		erase_cmd_seq[5].magic = 0x30;
+	}
+
+	res = xmc4xxx_write_command_sequence(bank, erase_cmd_seq,
+					     ARRAY_SIZE(erase_cmd_seq));
+	if (res != ERROR_OK)
+		return res;
+
+	/* Read the flash status register */
+	res = target_read_u32(bank->target, FLASH_REG_FLASH0_FSR, &status);
+	if (res != ERROR_OK) {
+		LOG_ERROR("Cannot read flash status register.");
+		return res;
+	}
+
+	/* Check for a sequence error */
+	if (status & FSR_SQER_MASK) {
+		LOG_ERROR("Error with flash erase sequence");
+		return ERROR_FAIL;
+	}
+
+	/* Make sure a flash erase was triggered */
+	if (!(status & FSR_ERASE_MASK)) {
+		LOG_ERROR("Flash failed to erase");
+		return ERROR_FAIL;
+	}
+
+	/* Now we must wait for the erase operation to end */
+	res = xmc4xxx_wait_status_busy(bank, FLASH_OP_TIMEOUT);
+
+	return res;
+}
+
+static int xmc4xxx_erase(struct flash_bank *bank, int first, int last)
+{
+	struct xmc4xxx_flash_bank *fb = bank->driver_priv;
+	int res;
+
+	if (bank->target->state != TARGET_HALTED) {
+		LOG_ERROR("Unable to erase, target is not halted");
+		return ERROR_TARGET_NOT_HALTED;
+	}
+
+	if (!fb->probed) {
+		res = xmc4xxx_probe(bank);
+		if (res != ERROR_OK)
+			return res;
+	}
+
+	uint32_t tmp_addr;
+	/* Loop through the sectors and erase each one */
+	for (int i = first; i <= last; i++) {
+		res = xmc4xxx_get_sector_start_addr(bank, i, &tmp_addr);
+		if (res != ERROR_OK) {
+			LOG_ERROR("Invalid sector %d", i);
+			return res;
+		}
+
+		LOG_DEBUG("Erasing sector %d @ 0x%08"PRIx32, i, tmp_addr);
+
+		res = xmc4xxx_erase_sector(bank, tmp_addr, false);
+		if (res != ERROR_OK) {
+			LOG_ERROR("Unable to write erase command sequence");
+			goto clear_status_and_exit;
+		}
+
+		/* Now we must wait for the erase operation to end */
+		res = xmc4xxx_wait_status_busy(bank, FLASH_OP_TIMEOUT);
+
+		if (res != ERROR_OK)
+			goto clear_status_and_exit;
+
+		bank->sectors[i].is_erased = 1;
+	}
+
+clear_status_and_exit:
+	res = xmc4xxx_clear_flash_status(bank);
+	return res;
+
+}
+
+static int xmc4xxx_enter_page_mode(struct flash_bank *bank)
+{
+	int res;
+	uint32_t status;
+
+	res = target_write_u32(bank->target, FLASH_CMD_ENTER_PAGEMODE, 0x50);
+	if (res != ERROR_OK) {
+		LOG_ERROR("Unable to write enter page mode command");
+		return ERROR_FAIL;
+	}
+
+	res = xmc4xxx_get_flash_status(bank, &status);
+
+	if (res != ERROR_OK)
+		return res;
+
+	/* Make sure we're in page mode */
+	if (!(status & FSR_PFPAGE_MASK)) {
+		LOG_ERROR("Unable to enter page mode");
+		return ERROR_FAIL;
+	}
+
+	/* Make sure we didn't encounter a sequence error */
+	if (status & FSR_SQER_MASK) {
+		LOG_ERROR("Sequence error while entering page mode");
+		return ERROR_FAIL;
+	}
+
+	return res;
+}
+
+/* The logical erase value of an xmc4xxx memory cell is 0x00,
+ * therefore, we cannot use the built in flash blank check and must
+ * implement our own */
+
+/** Checks whether a memory region is zeroed. */
+int xmc4xxx_blank_check_memory(struct target *target,
+	uint32_t address, uint32_t count, uint32_t *blank)
+{
+	struct working_area *erase_check_algorithm;
+	struct reg_param reg_params[3];
+	struct armv7m_algorithm armv7m_info;
+	int retval;
+
+	/* see contrib/loaders/erase_check/armv7m_0_erase_check.s for src */
+
+	static const uint8_t erase_check_code[] = {
+		/* loop: */
+		0x03, 0x78,		/* ldrb	r3, [r0] */
+		0x01, 0x30,		/* adds	r0, #1 */
+		0x1A, 0x43,		/* orrs	r2, r2, r3 */
+		0x01, 0x39,		/* subs	r1, r1, #1 */
+		0xFA, 0xD1,		/* bne	loop */
+		0x00, 0xBE		/* bkpt	#0 */
+	};
+
+	/* make sure we have a working area */
+	if (target_alloc_working_area(target, sizeof(erase_check_code),
+		&erase_check_algorithm) != ERROR_OK)
+		return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
+
+	retval = target_write_buffer(target, erase_check_algorithm->address,
+			sizeof(erase_check_code), (uint8_t *)erase_check_code);
+	if (retval != ERROR_OK)
+		return retval;
+
+	armv7m_info.common_magic = ARMV7M_COMMON_MAGIC;
+	armv7m_info.core_mode = ARM_MODE_THREAD;
+
+	init_reg_param(&reg_params[0], "r0", 32, PARAM_OUT);
+	buf_set_u32(reg_params[0].value, 0, 32, address);
+
+	init_reg_param(&reg_params[1], "r1", 32, PARAM_OUT);
+	buf_set_u32(reg_params[1].value, 0, 32, count);
+
+	init_reg_param(&reg_params[2], "r2", 32, PARAM_IN_OUT);
+	buf_set_u32(reg_params[2].value, 0, 32, 0x00);
+
+	retval = target_run_algorithm(target,
+				      0,
+				      NULL,
+				      3,
+				      reg_params,
+				      erase_check_algorithm->address,
+				      erase_check_algorithm->address + (sizeof(erase_check_code) - 2),
+				      10000,
+				      &armv7m_info);
+
+	if (retval == ERROR_OK)
+		*blank = buf_get_u32(reg_params[2].value, 0, 32);
+
+	destroy_reg_param(&reg_params[0]);
+	destroy_reg_param(&reg_params[1]);
+	destroy_reg_param(&reg_params[2]);
+
+	target_free_working_area(target, erase_check_algorithm);
+
+	return retval;
+}
+
+static int xmc4xxx_flash_blank_check(struct flash_bank *bank)
+{
+	struct target *target = bank->target;
+	int i;
+	int retval;
+	uint32_t blank;
+
+	if (bank->target->state != TARGET_HALTED) {
+		LOG_ERROR("Target not halted");
+		return ERROR_TARGET_NOT_HALTED;
+	}
+
+	for (i = 0; i < bank->num_sectors; i++) {
+		uint32_t address = bank->base + bank->sectors[i].offset;
+		uint32_t size = bank->sectors[i].size;
+
+		LOG_DEBUG("Erase checking 0x%08"PRIx32, address);
+		retval = xmc4xxx_blank_check_memory(target, address, size, &blank);
+
+		if (retval != ERROR_OK)
+			break;
+
+		if (blank == 0x00)
+			bank->sectors[i].is_erased = 1;
+		else
+			bank->sectors[i].is_erased = 0;
+	}
+
+	return ERROR_OK;
+}
+
+static int xmc4xxx_write_page(struct flash_bank *bank, const uint8_t *pg_buf,
+			      uint32_t offset, bool user_config)
+{
+	int res;
+	uint32_t status;
+
+	/* Base of the flash write command */
+	struct xmc4xxx_command_seq write_cmd_seq[4] = {
+		{FLASH_CMD_WRITE_PAGE_1, 0xAA},
+		{FLASH_CMD_WRITE_PAGE_2, 0x55},
+		{FLASH_CMD_WRITE_PAGE_3, 0xFF}, /* Needs filled in */
+		{0xFF,                   0xFF}	/* Needs filled in */
+	};
+
+	/* The command sequence differs depending on whether this is
+	 * being written to standard flash or the user configuration
+	 * area */
+	if (user_config)
+		write_cmd_seq[2].magic = 0xC0;
+	else
+		write_cmd_seq[2].magic = 0xA0;
+
+	/* Finally, we need to add the address that this page will be
+	 * written to */
+	write_cmd_seq[3].address = bank->base + offset;
+	write_cmd_seq[3].magic = 0xAA;
+
+
+	/* Flash pages are written 256 bytes at a time.  For each 256
+	 * byte chunk, we need to:
+	 * 1. Enter page mode. This activates the flash write buffer
+	 * 2. Load the page buffer with data (2x 32 bit words at a time)
+	 * 3. Burn the page buffer into its intended location
+	 * If the starting offset is not on a 256 byte boundary, we
+	 * will need to pad the beginning of the write buffer
+	 * accordingly. Likewise, if the last page does not fill the
+	 * buffer, we should pad it to avoid leftover data from being
+	 * written to flash
+	 */
+	res = xmc4xxx_enter_page_mode(bank);
+	if (res != ERROR_OK)
+		return res;
+
+	/* Copy the data into the page buffer*/
+	for (int i = 0; i < 256; i += 8) {
+		uint32_t w_lo = target_buffer_get_u32(bank->target, &pg_buf[i]);
+		uint32_t w_hi = target_buffer_get_u32(bank->target, &pg_buf[i + 4]);
+		LOG_DEBUG("WLO: %08"PRIx32, w_lo);
+		LOG_DEBUG("WHI: %08"PRIx32, w_hi);
+
+		/* Data is loaded 2x 32 bit words at a time */
+		res = target_write_u32(bank->target, FLASH_CMD_LOAD_PAGE_1, w_lo);
+		if (res != ERROR_OK)
+			return res;
+
+		res = target_write_u32(bank->target, FLASH_CMD_LOAD_PAGE_2, w_hi);
+		if (res != ERROR_OK)
+			return res;
+
+		/* Check for an error */
+		res = xmc4xxx_get_flash_status(bank, &status);
+		if (res != ERROR_OK)
+			return res;
+
+		if (status & FSR_SQER_MASK) {
+			LOG_ERROR("Error loading page buffer");
+			return ERROR_FAIL;
+		}
+	}
+
+	/* The page buffer is now full, time to commit it to flash */
+
+	res = xmc4xxx_write_command_sequence(bank, write_cmd_seq, ARRAY_SIZE(write_cmd_seq));
+	if (res != ERROR_OK) {
+		LOG_ERROR("Unable to enter write command sequence");
+		return res;
+	}
+
+	/* Read the flash status register */
+	res = xmc4xxx_get_flash_status(bank, &status);
+	if (res != ERROR_OK)
+		return res;
+
+	/* Check for a sequence error */
+	if (status & FSR_SQER_MASK) {
+		LOG_ERROR("Error with flash write sequence");
+		return ERROR_FAIL;
+	}
+
+	/* Make sure a flash write was triggered */
+	if (!(status & FSR_PROG_MASK)) {
+		LOG_ERROR("Failed to write flash page");
+		return ERROR_FAIL;
+	}
+
+	/* Wait for the write operation to end */
+	res = xmc4xxx_wait_status_busy(bank, FLASH_OP_TIMEOUT);
+	if (res != ERROR_OK)
+		return res;
+
+	/* TODO: Verify that page was written without error */
+	return res;
+}
+
+static int xmc4xxx_write(struct flash_bank *bank, const uint8_t *buffer,
+			 uint32_t offset, uint32_t count)
+{
+	struct xmc4xxx_flash_bank *fb = bank->driver_priv;
+	int res = ERROR_OK;
+
+	if (bank->target->state != TARGET_HALTED) {
+		LOG_ERROR("Unable to erase, target is not halted");
+		return ERROR_TARGET_NOT_HALTED;
+	}
+
+	if (!fb->probed) {
+		res = xmc4xxx_probe(bank);
+		if (res != ERROR_OK)
+			return res;
+	}
+
+	/* Make sure we won't run off the end of the flash bank */
+	if ((offset + count) > (bank->size)) {
+		LOG_ERROR("Attempting to write past the end of flash");
+		return ERROR_FAIL;
+	}
+
+
+	/* Attempt to write the passed in buffer to flash */
+	/* Pages are written 256 bytes at a time, we need to handle
+	 * scenarios where padding is required at the beginning and
+	 * end of a page */
+	while (count) {
+		/* page working area */
+		uint8_t tmp_buf[256] = {0};
+
+		/* Amount of data we'll be writing to this page */
+		int remaining;
+		int end_pad;
+
+		remaining = MIN(count, sizeof(tmp_buf));
+		end_pad   = sizeof(tmp_buf) - remaining;
+
+		/* Make sure we're starting on a page boundary */
+		int start_pad = offset % 256;
+		if (start_pad) {
+			LOG_INFO("Write does not start on a 256 byte boundary. "
+				 "Padding by %d bytes", start_pad);
+			memset(tmp_buf, 0xff, start_pad);
+			/* Subtract the amount of start offset from
+			 * the amount of data we'll need to write */
+			remaining -= start_pad;
+		}
+
+		/* Remove the amount we'll be writing from the total count */
+		count -= remaining;
+
+		/* Now copy in the remaining data */
+		memcpy(&tmp_buf[start_pad], buffer, remaining);
+
+		if (end_pad) {
+			LOG_INFO("Padding end of page @%08"PRIx32" by %d bytes",
+				 bank->base + offset, end_pad);
+			memset(&tmp_buf[256 - end_pad], 0xff, end_pad);
+		}
+
+		/* Now commit this page to flash, if there was start
+		 * padding, we should subtract that from the target offset */
+		res = xmc4xxx_write_page(bank, tmp_buf, (offset - start_pad), false);
+		if (res != ERROR_OK) {
+			LOG_ERROR("Unable to write flash page");
+			goto abort_write_and_exit;
+		}
+
+		/* Advance the buffer pointer */
+		buffer += remaining;
+
+		/* Advance the offset */
+		offset += remaining;
+	}
+
+abort_write_and_exit:
+	xmc4xxx_clear_flash_status(bank);
+	return res;
+
+}
+
+static int xmc4xxx_get_info_command(struct flash_bank *bank, char *buf, int buf_size)
+{
+	struct xmc4xxx_flash_bank *fb = bank->driver_priv;
+	uint32_t scu_idcode;
+
+	if (bank->target->state != TARGET_HALTED) {
+		LOG_WARNING("Cannot communicate... target not halted.");
+		return ERROR_TARGET_NOT_HALTED;
+	}
+
+	/* The SCU registers contain the ID of the chip */
+	int res = target_read_u32(bank->target, SCU_REG_BASE + SCU_ID_CHIP, &scu_idcode);
+	if (res != ERROR_OK) {
+		LOG_ERROR("Cannot read device identification register.");
+		return res;
+	}
+
+	uint16_t dev_id = (scu_idcode & 0xfff0) >> 4;
+	uint16_t rev_id = scu_idcode & 0xf;
+	const char *dev_str;
+	const char *rev_str = NULL;
+
+	switch (dev_id) {
+	case 0x100:
+		dev_str = "XMC4100";
+
+		switch (rev_id) {
+		case 0x1:
+			rev_str = "AA";
+			break;
+		case 0x2:
+			rev_str = "AB";
+			break;
+		}
+		break;
+	case 0x200:
+		dev_str = "XMC4200";
+
+		switch (rev_id) {
+		case 0x1:
+			rev_str = "AA";
+			break;
+		case 0x2:
+			rev_str = "AB";
+			break;
+		}
+		break;
+	case 0x400:
+		dev_str = "XMC4400";
+
+		switch (rev_id) {
+		case 0x1:
+			rev_str = "AA";
+			break;
+		case 0x2:
+			rev_str = "AB";
+			break;
+		}
+		break;
+	case 0x500:
+		dev_str = "XMC4500";
+
+		switch (rev_id) {
+		case 0x2:
+			rev_str = "AA";
+			break;
+		case 0x3:
+			rev_str = "AB";
+			break;
+		case 0x4:
+			rev_str = "AC";
+			break;
+		}
+		break;
+
+	default:
+		snprintf(buf, buf_size,
+			 "Cannot identify target as an XMC4xxx. SCU_ID: %"PRIx32"\n",
+			 scu_idcode);
+		return ERROR_OK;
+	}
+
+	/* String to declare protection data held in the private driver */
+	char prot_str[512] = {0};
+	if (fb->read_protected)
+		snprintf(prot_str, sizeof(prot_str), "\nFlash is read protected");
+
+	bool otp_enabled = false;
+	for (int i = 0; i < bank->num_sectors; i++)
+		if (fb->write_prot_otp[i])
+			otp_enabled = true;
+
+	/* If OTP Write protection is enabled (User 2), list each
+	 * sector that has it enabled */
+	char otp_str[8];
+	if (otp_enabled) {
+		strcat(prot_str, "\nOTP Protection is enabled for sectors:\n");
+		for (int i = 0; i < bank->num_sectors; i++) {
+			if (fb->write_prot_otp[i]) {
+				snprintf(otp_str, sizeof(otp_str), "- %d\n", i);
+				strncat(prot_str, otp_str, ARRAY_SIZE(otp_str));
+			}
+		}
+	}
+
+	if (rev_str != NULL)
+		snprintf(buf, buf_size, "%s - Rev: %s%s",
+			 dev_str, rev_str, prot_str);
+	else
+		snprintf(buf, buf_size, "%s - Rev: unknown (0x%01x)%s",
+			 dev_str, rev_id, prot_str);
+
+	return ERROR_OK;
+}
+
+static int xmc4xxx_temp_unprotect(struct flash_bank *bank, int user_level)
+{
+	struct xmc4xxx_flash_bank *fb;
+	int res = ERROR_OK;
+	uint32_t status = 0;
+
+	struct xmc4xxx_command_seq temp_unprot_seq[6] = {
+		{FLASH_CMD_TEMP_UNPROT_1, 0xAA},
+		{FLASH_CMD_TEMP_UNPROT_2, 0x55},
+		{FLASH_CMD_TEMP_UNPROT_3, 0xFF}, /* Needs filled in */
+		{FLASH_CMD_TEMP_UNPROT_4, 0xFF}, /* Needs filled in */
+		{FLASH_CMD_TEMP_UNPROT_5, 0xFF}, /* Needs filled in */
+		{FLASH_CMD_TEMP_UNPROT_6, 0x05}
+	};
+
+	if (user_level < 0 || user_level > 2) {
+		LOG_ERROR("Invalid user level, must be 0-2");
+		return ERROR_FAIL;
+	}
+
+	fb = bank->driver_priv;
+
+	/* Fill in the user level and passwords */
+	temp_unprot_seq[2].magic = user_level;
+	temp_unprot_seq[3].magic = fb->pw1;
+	temp_unprot_seq[4].magic = fb->pw2;
+
+	res = xmc4xxx_write_command_sequence(bank, temp_unprot_seq,
+					     ARRAY_SIZE(temp_unprot_seq));
+	if (res != ERROR_OK) {
+		LOG_ERROR("Unable to write temp unprotect sequence");
+		return res;
+	}
+
+	res = xmc4xxx_get_flash_status(bank, &status);
+	if (res != ERROR_OK)
+		return res;
+
+	if (status & FSR_WPRODIS0) {
+		LOG_INFO("Flash is temporarily unprotected");
+	} else {
+		LOG_INFO("Unable to disable flash protection");
+		res = ERROR_FAIL;
+	}
+
+
+	return res;
+}
+
+static int xmc4xxx_flash_unprotect(struct flash_bank *bank, int32_t level)
+{
+	uint32_t addr;
+	int res;
+
+	if ((level < 0) || (level > 1)) {
+		LOG_ERROR("Invalid user level. Must be 0-1");
+		return ERROR_FAIL;
+	}
+
+	switch (level) {
+	case 0:
+		addr = UCB0_BASE;
+		break;
+	case 1:
+		addr = UCB1_BASE;
+		break;
+	}
+
+	res = xmc4xxx_erase_sector(bank, addr, true);
+
+	if (res != ERROR_OK)
+		LOG_ERROR("Error erasing user configuration block");
+
+	return res;
+}
+
+/* Reference: "XMC4500 Flash Protection.pptx" app note */
+static int xmc4xxx_flash_protect(struct flash_bank *bank, int level, bool read_protect,
+				 int first, int last)
+{
+	/* User configuration block buffers */
+	uint8_t ucp0_buf[8 * sizeof(uint32_t)] = {0};
+	uint32_t ucb_base = 0;
+	uint32_t procon = 0;
+	int res = ERROR_OK;
+	uint32_t status = 0;
+	bool proin = false;
+
+	struct xmc4xxx_flash_bank *fb = bank->driver_priv;
+
+	/* Read protect only works for user 0, make sure we don't try
+	 * to do something silly */
+	if (level != 0 && read_protect) {
+		LOG_ERROR("Read protection is for user level 0 only!");
+		return ERROR_FAIL;
+	}
+
+	/* Check to see if protection is already installed for the
+	 * specified user level.  If it is, the user configuration
+	 * block will need to be erased before we can continue */
+
+	/* Grab the flash status register*/
+	res = xmc4xxx_get_flash_status(bank, &status);
+	if (res != ERROR_OK)
+		return res;
+
+	switch (level) {
+	case 0:
+		if ((status & FSR_RPROIN_MASK) || (status & FSR_WPROIN0_MASK))
+			proin = true;
+		break;
+	case 1:
+		if (status & FSR_WPROIN1_MASK)
+			proin = true;
+		break;
+	case 2:
+		if (status & FSR_WPROIN2_MASK)
+			proin = true;
+		break;
+	}
+
+	if (proin) {
+		LOG_ERROR("Flash protection is installed for user %d"
+			  " and must be removed before continuing", level);
+		return ERROR_FAIL;
+	}
+
+	/* If this device has 12 flash sectors, protection for
+	 * sectors 10 & 11 are handled jointly. If we are trying to
+	 * write all sectors, we should decrement
+	 * last to ensure we don't write to a register bit that
+	 * doesn't exist*/
+	if ((bank->num_sectors == 12) && (last == 12))
+		last--;
+
+	/*  We need to fill out the procon register representation
+	 *   that we will be writing to the device */
+	for (int i = first; i <= last; i++)
+		procon |= 1 << i;
+
+	/* If read protection is requested, set the appropriate bit
+	 * (we checked that this is allowed above) */
+	if (read_protect)
+		procon |= PROCON_RPRO_MASK;
+
+	LOG_DEBUG("Setting flash protection with procon:");
+	LOG_DEBUG("PROCON: %"PRIx32, procon);
+
+	/* First we need to copy in the procon register to the buffer
+	 * we're going to attempt to write.  This is written twice */
+	target_buffer_set_u32(bank->target, &ucp0_buf[0 * 4], procon);
+	target_buffer_set_u32(bank->target, &ucp0_buf[2 * 4], procon);
+
+	/* Now we must copy in both flash passwords.  As with the
+	 * procon data, this must be written twice (4 total words
+	 * worth of data) */
+	target_buffer_set_u32(bank->target, &ucp0_buf[4 * 4], fb->pw1);
+	target_buffer_set_u32(bank->target, &ucp0_buf[5 * 4], fb->pw2);
+	target_buffer_set_u32(bank->target, &ucp0_buf[6 * 4], fb->pw1);
+	target_buffer_set_u32(bank->target, &ucp0_buf[7 * 4], fb->pw2);
+
+	/* Finally, (if requested) we copy in the confirmation
+	 * code so that the protection is permanent and will
+	 * require a password to undo. */
+	target_buffer_set_u32(bank->target, &ucp0_buf[0 * 4], FLASH_PROTECT_CONFIRMATION_CODE);
+	target_buffer_set_u32(bank->target, &ucp0_buf[2 * 4], FLASH_PROTECT_CONFIRMATION_CODE);
+
+	/* Now that the data is copied into place, we must write
+	 * these pages into flash */
+
+	/* The user configuration block base depends on what level of
+	 * protection we're trying to install, select the proper one */
+	switch (level) {
+	case 0:
+		ucb_base = UCB0_BASE;
+		break;
+	case 1:
+		ucb_base = UCB1_BASE;
+		break;
+	case 2:
+		ucb_base = UCB2_BASE;
+		break;
+	}
+
+	/* Write the user config pages */
+	res = xmc4xxx_write_page(bank, ucp0_buf, ucb_base, true);
+	if (res != ERROR_OK) {
+		LOG_ERROR("Error writing user configuration block 0");
+		return res;
+	}
+
+	return ERROR_OK;
+}
+
+static int xmc4xxx_protect(struct flash_bank *bank, int set, int first, int last)
+{
+	int ret;
+	struct xmc4xxx_flash_bank *fb = bank->driver_priv;
+
+	/* Check for flash passwords */
+	if (!fb->pw_set) {
+		LOG_ERROR("Flash passwords not set, use xmc4xxx flash_password to set them");
+		return ERROR_FAIL;
+	}
+
+	/* We want to clear flash protection temporarily*/
+	if (set == 0) {
+		LOG_WARNING("Flash protection will be temporarily disabled"
+			    " for all pages (User 0 only)!");
+		ret = xmc4xxx_temp_unprotect(bank, 0);
+		return ret;
+	}
+
+	/* Install write protection for user 0 on the specified pages */
+	ret = xmc4xxx_flash_protect(bank, 0, false, first, last);
+
+	return ret;
+}
+
+static int xmc4xxx_protect_check(struct flash_bank *bank)
+{
+	int ret;
+	uint32_t protection[3] = {0};
+	struct xmc4xxx_flash_bank *fb = bank->driver_priv;
+
+	ret = target_read_u32(bank->target, FLASH_REG_FLASH0_PROCON0, &protection[0]);
+	if (ret != ERROR_OK) {
+		LOG_ERROR("Unable to read flash User0 protection register");
+		return ret;
+	}
+
+	ret = target_read_u32(bank->target, FLASH_REG_FLASH0_PROCON1, &protection[1]);
+	if (ret != ERROR_OK) {
+		LOG_ERROR("Unable to read flash User1 protection register");
+		return ret;
+	}
+
+	ret = target_read_u32(bank->target, FLASH_REG_FLASH0_PROCON2, &protection[2]);
+	if (ret != ERROR_OK) {
+		LOG_ERROR("Unable to read flash User2 protection register");
+		return ret;
+	}
+
+	int sectors = bank->num_sectors;
+
+	/* On devices with 12 sectors, sectors 10 & 11 are ptected
+	 * together instead of individually */
+	if (sectors == 12)
+		sectors--;
+
+	/* Clear the protection status */
+	for (int i = 0; i < bank->num_sectors; i++) {
+		bank->sectors[i].is_protected = 0;
+		fb->write_prot_otp[i] = false;
+	}
+	fb->read_protected = false;
+
+	/* The xmc4xxx series supports 3 levels of user protection
+	 * (User0, User1 (low priority), and User 2(OTP), we need to
+	 * check all 3 */
+	for (unsigned int i = 0; i < ARRAY_SIZE(protection); i++) {
+
+		/* Check for write protection on every available
+		*  sector */
+		for (int j = 0; j < sectors; j++) {
+			int set = (protection[i] & (1 << j)) ? 1 : 0;
+			bank->sectors[j].is_protected |= set;
+
+			/* Handle sector 11 */
+			if (j == 10)
+				bank->sectors[j + 1].is_protected |= set;
+
+			/* User 2 indicates this protection is
+			 * permanent, make note in the private driver structure */
+			if (i == 2 && set) {
+				fb->write_prot_otp[j] = true;
+
+				/* Handle sector 11 */
+				if (j == 10)
+					fb->write_prot_otp[j + 1] = true;
+			}
+
+		}
+	}
+
+	/* XMC4xxx also supports read proptection, make a note
+	 * in the private driver structure */
+	if (protection[0] & PROCON_RPRO_MASK)
+		fb->read_protected = true;
+
+	return ERROR_OK;
+}
+
+FLASH_BANK_COMMAND_HANDLER(xmc4xxx_flash_bank_command)
+{
+	bank->driver_priv = malloc(sizeof(struct xmc4xxx_flash_bank));
+
+	if (!bank->driver_priv)
+		return ERROR_FLASH_OPERATION_FAILED;
+
+	(void)memset(bank->driver_priv, 0, sizeof(struct xmc4xxx_flash_bank));
+
+	return ERROR_OK;
+}
+
+COMMAND_HANDLER(xmc4xxx_handle_flash_password_command)
+{
+	int res;
+	struct flash_bank *bank;
+
+	if (CMD_ARGC < 3)
+		return ERROR_COMMAND_SYNTAX_ERROR;
+
+	res = CALL_COMMAND_HANDLER(flash_command_get_bank, 0, &bank);
+	if (res != ERROR_OK)
+		return res;
+
+	struct xmc4xxx_flash_bank *fb = bank->driver_priv;
+
+	errno = 0;
+
+	/* We skip over the flash bank */
+	fb->pw1 = strtol(CMD_ARGV[1], NULL, 16);
+
+	if (errno)
+		return ERROR_COMMAND_SYNTAX_ERROR;
+
+	fb->pw2 = strtol(CMD_ARGV[2], NULL, 16);
+
+	if (errno)
+		return ERROR_COMMAND_SYNTAX_ERROR;
+
+	fb->pw_set = true;
+
+	command_print(CMD_CTX, "XMC4xxx flash passwords set to:\n");
+	command_print(CMD_CTX, "-0x%08"PRIx32"\n", fb->pw1);
+	command_print(CMD_CTX, "-0x%08"PRIx32"\n", fb->pw2);
+	return ERROR_OK;
+}
+
+COMMAND_HANDLER(xmc4xxx_handle_flash_unprotect_command)
+{
+	struct flash_bank *bank;
+	int res;
+	int32_t level;
+
+	if (CMD_ARGC < 2)
+		return ERROR_COMMAND_SYNTAX_ERROR;
+
+	res = CALL_COMMAND_HANDLER(flash_command_get_bank, 0, &bank);
+	if (res != ERROR_OK)
+		return res;
+
+	COMMAND_PARSE_NUMBER(s32, CMD_ARGV[1], level);
+
+	res = xmc4xxx_flash_unprotect(bank, level);
+
+	return res;
+}
+
+static const struct command_registration xmc4xxx_exec_command_handlers[] = {
+	{
+		.name = "flash_password",
+		.handler = xmc4xxx_handle_flash_password_command,
+		.mode = COMMAND_EXEC,
+		.usage = "bank_id password1 password2",
+		.help = "Set the flash passwords used for protect operations. "
+		"Passwords should be in standard hex form (0x00000000). "
+		"(You must call this before any other protect commands) "
+		"NOTE: The xmc4xxx's UCB area only allows for FOUR cycles. "
+		"Please use protection carefully!",
+	},
+	{
+		.name = "flash_unprotect",
+		.handler = xmc4xxx_handle_flash_unprotect_command,
+		.mode = COMMAND_EXEC,
+		.usage = "bank_id user_level[0-1]",
+		.help = "Permanently Removes flash protection (read and write) "
+		"for the specified user level",
+	},	COMMAND_REGISTRATION_DONE
+};
+
+static const struct command_registration xmc4xxx_command_handlers[] = {
+	{
+		.name = "xmc4xxx",
+		.mode = COMMAND_ANY,
+		.help = "xmc4xxx flash command group",
+		.usage = "",
+		.chain = xmc4xxx_exec_command_handlers,
+	},
+	COMMAND_REGISTRATION_DONE
+};
+
+struct flash_driver xmc4xxx_flash = {
+	.name = "xmc4xxx",
+	.commands = xmc4xxx_command_handlers,
+	.flash_bank_command = xmc4xxx_flash_bank_command,
+	.erase = xmc4xxx_erase,
+	.write = xmc4xxx_write,
+	.read = default_flash_read,
+	.probe = xmc4xxx_probe,
+	.auto_probe = xmc4xxx_probe,
+	.erase_check = xmc4xxx_flash_blank_check,
+	.info = xmc4xxx_get_info_command,
+	.protect_check = xmc4xxx_protect_check,
+	.protect = xmc4xxx_protect,
+};
diff --git a/tcl/target/xmc4xxx.cfg b/tcl/target/xmc4xxx.cfg
index 34f0327..bc00777 100644
--- a/tcl/target/xmc4xxx.cfg
+++ b/tcl/target/xmc4xxx.cfg
@@ -39,6 +39,19 @@ swj_newdap $_CHIPNAME cpu -irlen 4 -expected-id $_CPU_TAPID
 set _TARGETNAME $_CHIPNAME.cpu
 target create $_TARGETNAME cortex_m -chain-position $_TARGETNAME
 
+# Work-area is a space in RAM used for flash programming
+# By default use 16 kB
+if { [info exists WORKAREASIZE] } {
+   set _WORKAREASIZE $WORKAREASIZE
+} else {
+   set _WORKAREASIZE 0x1000
+}
+
+$_TARGETNAME configure -work-area-phys 0x20000000 -work-area-size $_WORKAREASIZE -work-area-backup 0
+
+set _FLASHNAME $_CHIPNAME.flash
+flash bank $_FLASHNAME xmc4xxx 0x0C000000 0 0 0 $_TARGETNAME
+
 if { ![using_hla] } {
 	cortex_m reset_config sysresetreq
 }