stm32x: add support for STM32F20x
authorØyvind Harboe <oyvind.harboe@zylin.com>
Mon, 31 Jan 2011 11:32:07 +0000 (12:32 +0100)
committerØyvind Harboe <oyvind.harboe@zylin.com>
Fri, 4 Feb 2011 09:55:43 +0000 (10:55 +0100)
ready for wider testing and comments on basic erase + programming.

Signed-off-by: Øyvind Harboe <oyvind.harboe@zylin.com>
contrib/loaders/flash/stm32f2xxx.S [new file with mode: 0644]
src/flash/nor/Makefile.am
src/flash/nor/drivers.c
src/flash/nor/stm32f2xxx.c [new file with mode: 0644]

diff --git a/contrib/loaders/flash/stm32f2xxx.S b/contrib/loaders/flash/stm32f2xxx.S
new file mode 100644 (file)
index 0000000..49c821b
--- /dev/null
@@ -0,0 +1,63 @@
+/***************************************************************************
+ *   Copyright (C) 2010 by Spencer Oliver                                  *
+ *   spen@spen-soft.co.uk                                                  *
+ *                                                                         *
+ *   Copyright (C) 2011 Øyvind Harboe                                      *
+ *   oyvind.harboe@zylin.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.                          *
+ *                                                                         *
+ *   You should have received a copy of the GNU General Public License     *
+ *   along with this program; if not, write to the                         *
+ *   Free Software Foundation, Inc.,                                       *
+ *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
+ ***************************************************************************/
+
+
+// Build : arm-eabi-gcc -c stm32f2xxx.S
+       .text
+       .syntax unified
+       .cpu cortex-m3
+       .thumb
+       .thumb_func
+       .global write
+
+/*
+       r0 - source address
+       r1 - target address
+       r2 - count (halfword-16bit)
+       r3 - result out
+       r4 - flash base
+*/
+
+#define STM32_FLASH_CR_OFFSET  0x10                    /* offset of CR register in FLASH struct */
+#define STM32_FLASH_SR_OFFSET  0x0c                    /* offset of CR register in FLASH struct */
+
+write:
+
+write_half_word:
+       ldr             r3, STM32_PROG16
+       str             r3, [r4, #STM32_FLASH_CR_OFFSET]
+       ldrh    r3, [r0], #0x02                                         /* read one half-word from src, increment ptr */
+       strh    r3, [r1], #0x02                                         /* write one half-word from src, increment ptr */
+busy:
+       ldr     r3, [r4, #STM32_FLASH_SR_OFFSET]
+       tst     r3, #0x10000                                            /* BSY (bit0) == 1 => operation in progress */
+       beq     busy                                                            /* wait more... */
+       tst             r3, #0xf0                                                       /* PGSERR | PGPERR | PGAERR | WRPERR */
+       bne             exit                                                            /* fail... */
+       subs    r2, r2, #0x01                                           /* decrement counter */
+       bne             write_half_word                                         /* write next half-word if anything left */
+exit:
+       bkpt    #0x00
+
+
+STM32_PROG16: .word 0x101                                              /* PG | PSIZE_16*/
index 42707e007ff7ccff69eec86cbd0c1122998b33f5..95bd313d3d5042c53065807ab751d6d267a22c6d 100644 (file)
@@ -25,6 +25,7 @@ NOR_DRIVERS = \
        stmsmi.c \
        stellaris.c \
        stm32x.c \
+       stm32f2xxx.c \
        str7x.c \
        str9x.c \
        str9xpec.c \
index f4479f6c56348fee0717b6ea04f1c6a143f4bce8..5489419f9c8a32b2d79710e46407f6b7f8179f1e 100644 (file)
@@ -33,6 +33,7 @@ extern struct flash_driver aduc702x_flash;
 extern struct flash_driver stellaris_flash;
 extern struct flash_driver str9xpec_flash;
 extern struct flash_driver stm32x_flash;
+extern struct flash_driver stm32xf2xxx_flash;
 extern struct flash_driver tms470_flash;
 extern struct flash_driver ecosflash_flash;
 extern struct flash_driver ocl_flash;
@@ -60,6 +61,7 @@ static struct flash_driver *flash_drivers[] = {
        &stellaris_flash,
        &str9xpec_flash,
        &stm32x_flash,
+       &stm32xf2xxx_flash,
        &tms470_flash,
        &ecosflash_flash,
        &ocl_flash,
diff --git a/src/flash/nor/stm32f2xxx.c b/src/flash/nor/stm32f2xxx.c
new file mode 100644 (file)
index 0000000..2ccf531
--- /dev/null
@@ -0,0 +1,712 @@
+/***************************************************************************
+ *   Copyright (C) 2005 by Dominic Rath                                    *
+ *   Dominic.Rath@gmx.de                                                   *
+ *                                                                         *
+ *   Copyright (C) 2008 by Spencer Oliver                                  *
+ *   spen@spen-soft.co.uk                                                  *
+ *                                                                         *
+ *   Copyright (C) 2011 Øyvind Harboe                                      *
+ *   oyvind.harboe@zylin.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.                          *
+ *                                                                         *
+ *   You should have received a copy of the GNU General Public License     *
+ *   along with this program; if not, write to the                         *
+ *   Free Software Foundation, Inc.,                                       *
+ *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
+ ***************************************************************************/
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "imp.h"
+#include <helper/binarybuffer.h>
+#include <target/algorithm.h>
+#include <target/armv7m.h>
+
+/* Regarding performance:
+ *
+ * Short story - it might be best to leave the performance at
+ * current levels.
+ *
+ * You may see a jump in speed if you change to using
+ * 32bit words for the block programming.
+ *
+ * Its a shame you cannot use the double word as its
+ * even faster - but you require external VPP for that mode.
+ *
+ * Having said all that 16bit writes give us the widest vdd
+ * operating range, so may be worth adding a note to that effect.
+ *
+ */
+
+
+/* Danger!!!! The STM32F1xxxx and STM32F2xxxx series actually have
+ * quite different flash controllers.
+ *
+ * What's more scary is that the names of the registers and their
+ * addresses are the same, but the actual bits and what they do are
+ * can be very different.
+ *
+ * To reduce testing complexity and dangers of regressions,
+ * a seperate file is used for stm32fx2222.
+ *
+ * 1mByte part with 4 x 16, 1 x 64, 7 x 128kBytes sectors
+ *
+ * What's the protection page size???
+ *
+ * Tested with STM3220F-EVAL board.
+ *
+ * STM32F21xx series for reference.
+ *
+ * RM0033
+ * http://www.st.com/internet/mcu/product/250192.jsp
+ *
+ * PM0059
+ * www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/PROGRAMMING_MANUAL/CD00233952.pdf
+ *
+ * STM32F1xxx series - notice that this code was copy, pasted and knocked
+ * into a stm32f2xxx driver, so in case something has been converted or
+ * bugs haven't been fixed, here are the original manuals:
+ *
+ * RM0008 - Reference manual
+ *
+ * RM0042, the Flash programming manual for low-, medium- high-density and
+ * connectivity line STM32F10xxx devices
+ *
+ * PM0068, the Flash programming manual for XL-density STM32F10xxx devices.
+ *
+ */
+
+ // Erase time can be as high as 1000ms, 10x this and it's toast...
+#define FLASH_ERASE_TIMEOUT 10000
+#define FLASH_WRITE_TIMEOUT 5
+
+
+#define STM32_FLASH_BASE       0x40023c00
+#define STM32_FLASH_ACR                0x40023c00
+#define STM32_FLASH_KEYR       0x40023c04
+#define STM32_FLASH_OPTKEYR    0x40023c08
+#define STM32_FLASH_SR         0x40023c0C
+#define STM32_FLASH_CR         0x40023c10
+#define STM32_FLASH_OPTCR      0x40023c14
+#define STM32_FLASH_OBR                0x40023c1C
+
+
+
+/* option byte location */
+
+#define STM32_OB_RDP           0x1FFFF800
+#define STM32_OB_USER          0x1FFFF802
+#define STM32_OB_DATA0         0x1FFFF804
+#define STM32_OB_DATA1         0x1FFFF806
+#define STM32_OB_WRP0          0x1FFFF808
+#define STM32_OB_WRP1          0x1FFFF80A
+#define STM32_OB_WRP2          0x1FFFF80C
+#define STM32_OB_WRP3          0x1FFFF80E
+
+/* FLASH_CR register bits */
+
+#define FLASH_PG               (1 << 0)
+#define FLASH_SER              (1 << 1)
+#define FLASH_MER              (1 << 2)
+#define FLASH_STRT             (1 << 16)
+#define FLASH_PSIZE_8  (0 << 8)
+#define FLASH_PSIZE_16 (1 << 8)
+#define FLASH_PSIZE_32 (2 << 8)
+#define FLASH_PSIZE_64 (3 << 8)
+#define FLASH_SNB(a)   ((a) << 3)
+#define FLASH_LOCK             (1 << 31)
+
+/* FLASH_SR register bits */
+
+#define FLASH_BSY              (1 << 16)
+#define FLASH_PGSERR   (1 << 7) // Programming sequence error
+#define FLASH_PGPERR   (1 << 6) // Programming parallelism error
+#define FLASH_PGAERR   (1 << 5) // Programming alignment error
+#define FLASH_WRPERR   (1 << 4) // Write protection error
+#define FLASH_OPERR            (1 << 1) // Operation error
+
+#define FLASH_ERROR (FLASH_PGSERR | FLASH_PGPERR | FLASH_PGAERR| FLASH_WRPERR| FLASH_OPERR)
+
+/* STM32_FLASH_OBR bit definitions (reading) */
+
+#define OPT_ERROR              0
+#define OPT_READOUT            1
+#define OPT_RDWDGSW            2
+#define OPT_RDRSTSTOP  3
+#define OPT_RDRSTSTDBY 4
+#define OPT_BFB2               5       /* dual flash bank only */
+
+/* register unlock keys */
+
+#define KEY1                   0x45670123
+#define KEY2                   0xCDEF89AB
+
+struct stm32x_flash_bank
+{
+       struct working_area *write_algorithm;
+       int probed;
+};
+
+
+/* flash bank stm32x <base> <size> 0 0 <target#>
+ */
+FLASH_BANK_COMMAND_HANDLER(stm32x_flash_bank_command)
+{
+       struct stm32x_flash_bank *stm32x_info;
+
+       if (CMD_ARGC < 6)
+       {
+               LOG_WARNING("incomplete flash_bank stm32x configuration");
+               return ERROR_FLASH_BANK_INVALID;
+       }
+
+       stm32x_info = malloc(sizeof(struct stm32x_flash_bank));
+       bank->driver_priv = stm32x_info;
+
+       stm32x_info->write_algorithm = NULL;
+       stm32x_info->probed = 0;
+
+       return ERROR_OK;
+}
+
+static inline int stm32x_get_flash_reg(struct flash_bank *bank, uint32_t reg)
+{
+       return reg;
+}
+
+static inline int stm32x_get_flash_status(struct flash_bank *bank, uint32_t *status)
+{
+       struct target *target = bank->target;
+       return target_read_u32(target, stm32x_get_flash_reg(bank, STM32_FLASH_SR), status);
+}
+
+static int stm32x_wait_status_busy(struct flash_bank *bank, int timeout)
+{
+       struct target *target = bank->target;
+       uint32_t status;
+       int retval = ERROR_OK;
+
+       /* wait for busy to clear */
+       for (;;)
+       {
+               retval = stm32x_get_flash_status(bank, &status);
+               if (retval != ERROR_OK)
+                       return retval;
+               LOG_DEBUG("status: 0x%" PRIx32 "", status);
+               if ((status & FLASH_BSY) == 0)
+                       break;
+               if (timeout-- <= 0)
+               {
+                       LOG_ERROR("timed out waiting for flash");
+                       return ERROR_FAIL;
+               }
+               alive_sleep(1);
+       }
+
+
+       if (status & FLASH_WRPERR)
+       {
+               LOG_ERROR("stm32x device protected");
+               retval = ERROR_FAIL;
+       }
+
+       /* Clear but report errors */
+       if (status & FLASH_ERROR)
+       {
+               /* If this operation fails, we ignore it and report the original
+                * retval
+                */
+               target_write_u32(target, stm32x_get_flash_reg(bank, STM32_FLASH_SR),
+                               status & FLASH_ERROR);
+       }
+       return retval;
+}
+
+static int stm32x_unlock_reg(struct target *target)
+{
+       /* unlock flash registers */
+       int retval = target_write_u32(target, STM32_FLASH_KEYR, KEY1);
+       if (retval != ERROR_OK)
+               return retval;
+
+       retval = target_write_u32(target, STM32_FLASH_KEYR, KEY2);
+       if (retval != ERROR_OK)
+               return retval;
+       return ERROR_OK;
+}
+
+static int stm32x_protect_check(struct flash_bank *bank)
+{
+       return ERROR_OK;
+}
+
+static int stm32x_erase(struct flash_bank *bank, int first, int last)
+{
+       struct target *target = bank->target;
+       int i;
+
+       if (bank->target->state != TARGET_HALTED)
+       {
+               LOG_ERROR("Target not halted");
+               return ERROR_TARGET_NOT_HALTED;
+       }
+
+       int retval;
+       retval = stm32x_unlock_reg(target);
+       if (retval != ERROR_OK)
+               return retval;
+
+       /*
+       Sector Erase
+       To erase a sector, follow the procedure below:
+       1. Check that no Flash memory operation is ongoing by checking the BSY bit in the
+         FLASH_SR register
+       2. Set the SER bit and select the sector (out of the 12 sectors in the main memory block)
+         you wish to erase (SNB) in the FLASH_CR register
+       3. Set the STRT bit in the FLASH_CR register
+       4. Wait for the BSY bit to be cleared
+        */
+
+       for (i = first; i <= last; i++)
+       {
+               retval = target_write_u32(target,
+                               stm32x_get_flash_reg(bank, STM32_FLASH_CR), FLASH_SER | FLASH_SNB(i) | FLASH_STRT);
+               if (retval != ERROR_OK)
+                       return retval;
+
+               retval = stm32x_wait_status_busy(bank, FLASH_ERASE_TIMEOUT);
+               if (retval != ERROR_OK)
+                       return retval;
+
+               bank->sectors[i].is_erased = 1;
+       }
+
+       retval = target_write_u32(target, stm32x_get_flash_reg(bank, STM32_FLASH_CR), FLASH_LOCK);
+       if (retval != ERROR_OK)
+               return retval;
+
+       return ERROR_OK;
+}
+
+static int stm32x_protect(struct flash_bank *bank, int set, int first, int last)
+{
+       return ERROR_OK;
+}
+
+static int stm32x_write_block(struct flash_bank *bank, uint8_t *buffer,
+               uint32_t offset, uint32_t count)
+{
+       struct stm32x_flash_bank *stm32x_info = bank->driver_priv;
+       struct target *target = bank->target;
+       uint32_t buffer_size = 16384;
+       struct working_area *source;
+       uint32_t address = bank->base + offset;
+       struct reg_param reg_params[5];
+       struct armv7m_algorithm armv7m_info;
+       int retval = ERROR_OK;
+
+       /* see contib/loaders/flash/stm32x.s for src */
+
+       static const uint16_t stm32x_flash_write_code_16[] = {
+//     00000000 <write>:
+          0x4b07, //           ldr     r3, [pc, #28]   (20 <STM32_PROG16>)
+          0x6123,  //          str     r3, [r4, #16]
+       0xf830, 0x3b02,         //ldrh.w        r3, [r0], #2
+       0xf821, 0x3b02,         //strh.w        r3, [r1], #2
+
+       //0000000c <busy>:
+       0x68e3,         //ldr   r3, [r4, #12]
+0xf413, 0x3f80, //     tst.w   r3, #65536      ; 0x10000
+0xd0fb,        //beq.n c <busy>
+0xf013, 0x0ff0,        //tst.w r3, #240        ; 0xf0
+0xd101,        //bne.n 1e <exit>
+0x3a01,        //subs  r2, #1
+0xd1f0,        //bne.n 0 <write>
+                               //0000001e <exit>:
+       0xbe00, //              bkpt    0x0000
+
+       //00000020 <STM32_PROG16>:
+       0x0101, 0x0000, //      .word   0x00000101
+
+       };
+
+       // Flip endian
+       uint8_t stm32x_flash_write_code[sizeof(stm32x_flash_write_code_16)*2];
+       for (unsigned i = 0; i < sizeof(stm32x_flash_write_code_16) / 2; i++)
+       {
+               stm32x_flash_write_code[i*2 + 0] = stm32x_flash_write_code_16[i] & 0xff;
+               stm32x_flash_write_code[i*2 + 1] = (stm32x_flash_write_code_16[i] >> 8) & 0xff;
+       }
+
+       if (target_alloc_working_area(target, sizeof(stm32x_flash_write_code),
+                       &stm32x_info->write_algorithm) != ERROR_OK)
+       {
+               LOG_WARNING("no working area available, can't do block memory writes");
+               return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
+       };
+
+       if ((retval = target_write_buffer(target, stm32x_info->write_algorithm->address,
+                       sizeof(stm32x_flash_write_code),
+                       (uint8_t*)stm32x_flash_write_code)) != ERROR_OK)
+               return retval;
+
+       /* memory buffer */
+       while (target_alloc_working_area_try(target, buffer_size, &source) != ERROR_OK)
+       {
+               buffer_size /= 2;
+               if (buffer_size <= 256)
+               {
+                       /* if we already allocated the writing code, but failed to get a
+                        * buffer, free the algorithm */
+                       if (stm32x_info->write_algorithm)
+                               target_free_working_area(target, stm32x_info->write_algorithm);
+
+                       LOG_WARNING("no large enough working area available, can't do block memory writes");
+                       return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
+               }
+       };
+
+       armv7m_info.common_magic = ARMV7M_COMMON_MAGIC;
+       armv7m_info.core_mode = ARMV7M_MODE_ANY;
+
+       init_reg_param(&reg_params[0], "r0", 32, PARAM_OUT);
+       init_reg_param(&reg_params[1], "r1", 32, PARAM_OUT);
+       init_reg_param(&reg_params[2], "r2", 32, PARAM_OUT);
+       init_reg_param(&reg_params[3], "r3", 32, PARAM_IN_OUT);
+       init_reg_param(&reg_params[4], "r4", 32, PARAM_OUT);
+
+       while (count > 0)
+       {
+               uint32_t thisrun_count = (count > (buffer_size / 2)) ?
+                               (buffer_size / 2) : count;
+
+               if ((retval = target_write_buffer(target, source->address,
+                               thisrun_count * 2, buffer)) != ERROR_OK)
+                       break;
+
+               buf_set_u32(reg_params[0].value, 0, 32, source->address);
+               buf_set_u32(reg_params[1].value, 0, 32, address);
+               buf_set_u32(reg_params[2].value, 0, 32, thisrun_count);
+               // R3 is a return value only
+               buf_set_u32(reg_params[4].value, 0, 32, STM32_FLASH_BASE);
+
+               if ((retval = target_run_algorithm(target, 0, NULL,
+                               sizeof(reg_params) / sizeof(*reg_params),
+                               reg_params,
+                               stm32x_info->write_algorithm->address,
+                               0,
+                               10000, &armv7m_info)) != ERROR_OK)
+               {
+                       LOG_ERROR("error executing stm32x flash write algorithm");
+                       break;
+               }
+
+               uint32_t error = buf_get_u32(reg_params[3].value, 0, 32) & FLASH_ERROR;
+
+               if (error & FLASH_WRPERR)
+               {
+                       LOG_ERROR("flash memory write protected");
+               }
+
+               if (error != 0)
+               {
+                       LOG_ERROR("flash write failed = %08x", error);
+                       /* Clear but report errors */
+                       target_write_u32(target, STM32_FLASH_SR, error);
+                       retval = ERROR_FAIL;
+                       break;
+               }
+
+               buffer += thisrun_count * 2;
+               address += thisrun_count * 2;
+               count -= thisrun_count;
+       }
+
+       target_free_working_area(target, source);
+       target_free_working_area(target, stm32x_info->write_algorithm);
+
+       destroy_reg_param(&reg_params[0]);
+       destroy_reg_param(&reg_params[1]);
+       destroy_reg_param(&reg_params[2]);
+       destroy_reg_param(&reg_params[3]);
+       destroy_reg_param(&reg_params[4]);
+
+       return retval;
+}
+
+static int stm32x_write(struct flash_bank *bank, uint8_t *buffer,
+               uint32_t offset, uint32_t count)
+{
+       struct target *target = bank->target;
+       uint32_t words_remaining = (count / 2);
+       uint32_t bytes_remaining = (count & 0x00000001);
+       uint32_t address = bank->base + offset;
+       uint32_t bytes_written = 0;
+       int retval;
+
+       if (bank->target->state != TARGET_HALTED)
+       {
+               LOG_ERROR("Target not halted");
+               return ERROR_TARGET_NOT_HALTED;
+       }
+
+       if (offset & 0x1)
+       {
+               LOG_WARNING("offset 0x%" PRIx32 " breaks required 2-byte alignment", offset);
+               return ERROR_FLASH_DST_BREAKS_ALIGNMENT;
+       }
+
+       retval = stm32x_unlock_reg(target);
+       if (retval != ERROR_OK)
+               return retval;
+
+       /* multiple half words (2-byte) to be programmed? */
+       if (words_remaining > 0)
+       {
+               /* try using a block write */
+               if ((retval = stm32x_write_block(bank, buffer, offset, words_remaining)) != ERROR_OK)
+               {
+                       if (retval == ERROR_TARGET_RESOURCE_NOT_AVAILABLE)
+                       {
+                               /* if block write failed (no sufficient working area),
+                                * we use normal (slow) single dword accesses */
+                               LOG_WARNING("couldn't use block writes, falling back to single memory accesses");
+                       }
+               }
+               else
+               {
+                       buffer += words_remaining * 2;
+                       address += words_remaining * 2;
+                       words_remaining = 0;
+               }
+       }
+
+       if ((retval != ERROR_OK) && (retval != ERROR_TARGET_RESOURCE_NOT_AVAILABLE))
+               return retval;
+
+       /*
+       Standard programming
+       The Flash memory programming sequence is as follows:
+       1. Check that no main Flash memory operation is ongoing by checking the BSY bit in the
+         FLASH_SR register.
+       2. Set the PG bit in the FLASH_CR register
+       3. Perform the data write operation(s) to the desired memory address (inside main
+         memory block or OTP area):
+       – – Half-word access in case of x16 parallelism
+       – Word access in case of x32 parallelism
+       –
+       4.
+       Byte access in case of x8 parallelism
+       Double word access in case of x64 parallelism
+       Wait for the BSY bit to be cleared
+       */
+       while (words_remaining > 0)
+       {
+               uint16_t value;
+               memcpy(&value, buffer + bytes_written, sizeof(uint16_t));
+
+               retval = target_write_u32(target, stm32x_get_flash_reg(bank, STM32_FLASH_CR),
+                               FLASH_PG | FLASH_PSIZE_16);
+               if (retval != ERROR_OK)
+                       return retval;
+
+               retval = target_write_u16(target, address, value);
+               if (retval != ERROR_OK)
+                       return retval;
+
+               retval = stm32x_wait_status_busy(bank, FLASH_WRITE_TIMEOUT);
+               if (retval != ERROR_OK)
+                       return retval;
+
+               bytes_written += 2;
+               words_remaining--;
+               address += 2;
+       }
+
+       if (bytes_remaining)
+       {
+               retval = target_write_u32(target, stm32x_get_flash_reg(bank, STM32_FLASH_CR),
+                               FLASH_PG | FLASH_PSIZE_8);
+               if (retval != ERROR_OK)
+                       return retval;
+               retval = target_write_u8(target, address, buffer[bytes_written]);
+               if (retval != ERROR_OK)
+                       return retval;
+
+               retval = stm32x_wait_status_busy(bank, FLASH_WRITE_TIMEOUT);
+               if (retval != ERROR_OK)
+                       return retval;
+       }
+
+       return target_write_u32(target, STM32_FLASH_CR, FLASH_LOCK);
+}
+
+static void setup_sector(struct flash_bank *bank, int start, int num, int size)
+{
+       for (int i = start; i < (start + num) ; i++)
+       {
+               bank->sectors[i].offset = bank->size;
+               bank->sectors[i].size = size;
+               bank->size += bank->sectors[i].size;
+       }
+}
+
+static int stm32x_probe(struct flash_bank *bank)
+{
+       struct target *target = bank->target;
+       struct stm32x_flash_bank *stm32x_info = bank->driver_priv;
+       int i;
+       uint16_t num_pages;
+       uint32_t device_id;
+       uint32_t base_address = 0x08000000;
+
+       stm32x_info->probed = 0;
+
+       /* read stm32 device id register */
+       int retval = target_read_u32(target, 0xE0042000, &device_id);
+       if (retval != ERROR_OK)
+               return retval;
+       LOG_INFO("device id = 0x%08" PRIx32 "", device_id);
+
+       /* get flash size from target. */
+       retval = target_read_u16(target, 0x1FFFF7E0, &num_pages);
+       if (retval != ERROR_OK)
+       {
+               LOG_WARNING("failed reading flash size, default to max target family");
+               /* failed reading flash size, default to max target family */
+               num_pages = 0xffff;
+       }
+
+       if ((device_id & 0x7ff) != 0x411)
+       {
+               LOG_WARNING("Cannot identify target as a STM32 family, try the other STM32 drivers.");
+               return ERROR_FAIL;
+       }
+
+       /* sectors sizes vary, handle this in a different code path
+        * than the rest.
+        */
+       // Uhhh.... what to use here?
+
+       /* calculate numbers of pages*/
+       num_pages = 4 + 1 + 7;
+
+       if (bank->sectors)
+       {
+               free(bank->sectors);
+               bank->sectors = NULL;
+       }
+
+       bank->base = base_address;
+       bank->num_sectors = num_pages;
+       bank->sectors = malloc(sizeof(struct flash_sector) * num_pages);
+
+       bank->size = 0;
+       setup_sector(bank, 0, 4, 16 * 1024);
+       setup_sector(bank, 4, 1, 64 * 1024);
+       setup_sector(bank, 4+1, 7, 128 * 1024);
+
+       for (i = 0; i < num_pages; i++)
+       {
+               bank->sectors[i].is_erased = -1;
+               bank->sectors[i].is_protected = 0;
+       }
+
+       LOG_INFO("flash size = %dkBytes", bank->size / 1024);
+
+       stm32x_info->probed = 1;
+
+       return ERROR_OK;
+}
+
+static int stm32x_auto_probe(struct flash_bank *bank)
+{
+       struct stm32x_flash_bank *stm32x_info = bank->driver_priv;
+       if (stm32x_info->probed)
+               return ERROR_OK;
+       return stm32x_probe(bank);
+}
+
+static int get_stm32x_info(struct flash_bank *bank, char *buf, int buf_size)
+{
+       struct target *target = bank->target;
+       uint32_t device_id;
+       int printed;
+
+       /* read stm32 device id register */
+       int retval = target_read_u32(target, 0xE0042000, &device_id);
+       if (retval != ERROR_OK)
+               return retval;
+
+       if ((device_id & 0x7ff) == 0x411)
+       {
+               printed = snprintf(buf, buf_size, "stm32x (1mByte part) - Rev: ");
+               buf += printed;
+               buf_size -= printed;
+
+               switch (device_id >> 16)
+               {
+                       case 0x1000:
+                               snprintf(buf, buf_size, "A");
+                               break;
+
+                       case 0x2000:
+                               snprintf(buf, buf_size, "B");
+                               break;
+
+                       case 0x1001:
+                               snprintf(buf, buf_size, "Z");
+                               break;
+
+                       default:
+                               snprintf(buf, buf_size, "unknown");
+                               break;
+               }
+       }
+       else
+       {
+               snprintf(buf, buf_size, "Cannot identify target as a stm32x\n");
+               return ERROR_FAIL;
+       }
+
+       return ERROR_OK;
+}
+
+static const struct command_registration stm32x_exec_command_handlers[] = {
+       COMMAND_REGISTRATION_DONE
+};
+
+static const struct command_registration stm32x_command_handlers[] = {
+       {
+               .name = "stm32f2xxx",
+               .mode = COMMAND_ANY,
+               .help = "stm32f2xxx flash command group",
+               .chain = stm32x_exec_command_handlers,
+       },
+       COMMAND_REGISTRATION_DONE
+};
+
+struct flash_driver stm32xf2xxx_flash = {
+       .name = "stm32f2xxx",
+       .commands = stm32x_command_handlers,
+       .flash_bank_command = stm32x_flash_bank_command,
+       .erase = stm32x_erase,
+       .protect = stm32x_protect,
+       .write = stm32x_write,
+       .read = default_flash_read,
+       .probe = stm32x_probe,
+       .auto_probe = stm32x_auto_probe,
+       .erase_check = default_flash_mem_blank_check,
+       .protect_check = stm32x_protect_check,
+       .info = get_stm32x_info,
+};