flash/stm32l4x: introduce flash programming without loader

this capability permits to program the flash if we cannot reserve a workarea.

the introduction the command 'stm32l4x flashloader <bank_id> [enable|disable]'
helps to automatically skip using the flashloader if needed.

Change-Id: Id29213c85ee5c7c487cfee21554f5a7ea50db6c9
Signed-off-by: Tarek BOCHKATI <tarek.bouchkati@gmail.com>
Reviewed-on: https://review.openocd.org/c/openocd/+/6273
Reviewed-by: Oleksij Rempel <linux@rempel-privat.de>
Tested-by: jenkins

diff --git a/doc/openocd.texi b/doc/openocd.texi
index 33812499ac4dbff6cbbb4e0234469468ae5ee297..4404807a639c9be22a96f3fc263ca95de2c2e39c 100644 (file)
--- a/doc/openocd.texi
+++ b/doc/openocd.texi
@@ -7344,6 +7344,13 @@ Unlocks the entire stm32 device.
 The @var{num} parameter is a value shown by @command{flash banks}.
 @end deffn
 
+@deffn Command {stm32l4x flashloader} num [@option{enable} | @option{disable}]
+Enables or disables the flashloader usage (enabled by default),
+when disabled it will fall back to direct memory access to program the Flash or OTP memories.
+if neither @option{enabled} nor @option{disable} are specified, the command will display
+the current configuration.
+@end deffn
+
 @deffn {Command} {stm32l4x mass_erase} num
 Mass erases the entire stm32l4x device.
 The @var{num} parameter is a value shown by @command{flash banks}.

diff --git a/src/flash/nor/stm32l4x.c b/src/flash/nor/stm32l4x.c
index de36d56c71796af5130835af7010190577e7dd17..5bc23090fbc6806e5a32e93405a1336b97d3b5ad 100644 (file)
--- a/src/flash/nor/stm32l4x.c
+++ b/src/flash/nor/stm32l4x.c
@@ -116,6 +116,7 @@
 /* Erase time can be as high as 25ms, 10x this and assume it's toast... */
 
 #define FLASH_ERASE_TIMEOUT 250
+#define FLASH_WRITE_TIMEOUT 50
 
 
 /* relevant STM32L4 flags ****************************************************/
@@ -223,6 +224,7 @@ struct stm32l4_flash_bank {
        uint32_t flash_regs_base;
        const uint32_t *flash_regs;
        bool otp_enabled;
+       bool use_flashloader;
        enum stm32l4_rdp rdp;
        bool tzen;
        uint32_t optr;
@@ -545,6 +547,7 @@ FLASH_BANK_COMMAND_HANDLER(stm32l4_flash_bank_command)
        stm32l4_info->probed = false;
        stm32l4_info->otp_enabled = false;
        stm32l4_info->user_bank_size = bank->size;
+       stm32l4_info->use_flashloader = true;
 
        return ERROR_OK;
 }
@@ -1362,6 +1365,49 @@ static int stm32l4_write_block(struct flash_bank *bank, const uint8_t *buffer,
        return retval;
 }
 
+/* Count is in double-words */
+static int stm32l4_write_block_without_loader(struct flash_bank *bank, const uint8_t *buffer,
+                               uint32_t offset, uint32_t count)
+{
+       struct target *target = bank->target;
+       uint32_t address = bank->base + offset;
+       int retval = ERROR_OK;
+
+       /* wait for BSY bit */
+       retval = stm32l4_wait_status_busy(bank, FLASH_WRITE_TIMEOUT);
+       if (retval != ERROR_OK)
+               return retval;
+
+       /* set PG in FLASH_CR */
+       retval = stm32l4_write_flash_reg_by_index(bank, STM32_FLASH_CR_INDEX, FLASH_PG);
+       if (retval != ERROR_OK)
+               return retval;
+
+
+       /* write directly to flash memory */
+       const uint8_t *src = buffer;
+       while (count--) {
+               retval = target_write_memory(target, address, 4, 2, src);
+               if (retval != ERROR_OK)
+                       return retval;
+
+               /* wait for BSY bit */
+               retval = stm32l4_wait_status_busy(bank, FLASH_WRITE_TIMEOUT);
+               if (retval != ERROR_OK)
+                       return retval;
+
+               src += 8;
+               address += 8;
+       }
+
+       /* reset PG in FLASH_CR */
+       retval = stm32l4_write_flash_reg_by_index(bank, STM32_FLASH_CR_INDEX, 0);
+       if (retval != ERROR_OK)
+               return retval;
+
+       return retval;
+}
+
 static int stm32l4_write(struct flash_bank *bank, const uint8_t *buffer,
        uint32_t offset, uint32_t count)
 {
@@ -1434,14 +1480,22 @@ static int stm32l4_write(struct flash_bank *bank, const uint8_t *buffer,
        if (retval != ERROR_OK)
                goto err_lock;
 
-       /* For TrustZone enabled devices, when TZEN is set and RDP level is 0.5,
-        * the debug is possible only in non-secure state.
-        * Thus means the flashloader will run in non-secure mode,
-        * and the workarea need to be in non-secure RAM */
-       if (stm32l4_info->tzen && (stm32l4_info->rdp == RDP_LEVEL_0_5))
-               LOG_INFO("RDP level is 0.5, the work-area should reside in non-secure RAM");
+       if (stm32l4_info->use_flashloader) {
+               /* For TrustZone enabled devices, when TZEN is set and RDP level is 0.5,
+                * the debug is possible only in non-secure state.
+                * Thus means the flashloader will run in non-secure mode,
+                * and the workarea need to be in non-secure RAM */
+               if (stm32l4_info->tzen && (stm32l4_info->rdp == RDP_LEVEL_0_5))
+                       LOG_INFO("RDP level is 0.5, the work-area should reside in non-secure RAM");
+
+               retval = stm32l4_write_block(bank, buffer, offset, count / 8);
+       }
+
+       if (!stm32l4_info->use_flashloader || retval == ERROR_TARGET_RESOURCE_NOT_AVAILABLE) {
+               LOG_INFO("falling back to single memory accesses");
+               retval = stm32l4_write_block_without_loader(bank, buffer, offset, count / 8);
+       }
 
-       retval = stm32l4_write_block(bank, buffer, offset, count / 8);
 
 err_lock:
        retval2 = stm32l4_write_flash_reg_by_index(bank, STM32_FLASH_CR_INDEX, FLASH_LOCK);
@@ -2017,6 +2071,26 @@ COMMAND_HANDLER(stm32l4_handle_trustzone_command)
        return stm32l4_perform_obl_launch(bank);
 }
 
+COMMAND_HANDLER(stm32l4_handle_flashloader_command)
+{
+       if (CMD_ARGC < 1 || CMD_ARGC > 2)
+               return ERROR_COMMAND_SYNTAX_ERROR;
+
+       struct flash_bank *bank;
+       int retval = CALL_COMMAND_HANDLER(flash_command_get_bank, 0, &bank);
+       if (retval != ERROR_OK)
+               return retval;
+
+       struct stm32l4_flash_bank *stm32l4_info = bank->driver_priv;
+
+       if (CMD_ARGC == 2)
+               COMMAND_PARSE_ENABLE(CMD_ARGV[1], stm32l4_info->use_flashloader);
+
+       command_print(CMD, "FlashLoader usage is %s", stm32l4_info->use_flashloader ? "enabled" : "disabled");
+
+       return ERROR_OK;
+}
+
 COMMAND_HANDLER(stm32l4_handle_option_load_command)
 {
        if (CMD_ARGC != 1)
@@ -2222,6 +2296,13 @@ static const struct command_registration stm32l4_exec_command_handlers[] = {
                .usage = "bank_id",
                .help = "Unlock entire protected flash device.",
        },
+       {
+               .name = "flashloader",
+               .handler = stm32l4_handle_flashloader_command,
+               .mode = COMMAND_EXEC,
+               .usage = "<bank_id> [enable|disable]",
+               .help = "Configure the flashloader usage",
+       },
        {
                .name = "mass_erase",
                .handler = stm32l4_handle_mass_erase_command,