altos: Add program flash function

[fw/altos] / src / stm / ao_flash_stm.c

diff --git a/src/stm/ao_flash_stm.c b/src/stm/ao_flash_stm.c
new file mode 100644 (file)
index 0000000..b3ef6a6
--- /dev/null
+++ b/src/stm/ao_flash_stm.c
@@ -0,0 +1,103 @@
+/*
+ * Copyright © 2013 Keith Packard <keithp@keithp.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; version 2 of the License.
+ *
+ * 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.
+ */
+
+#include <ao.h>
+#include <ao_flash_stm.h>
+
+static uint8_t
+ao_flash_pecr_is_locked(void)
+{
+       return (stm_flash.pecr & (1 << STM_FLASH_PECR_PELOCK)) != 0;
+}
+
+static uint8_t
+ao_flash_pgr_is_locked(void)
+{
+       return (stm_flash.pecr & (1 << STM_FLASH_PECR_PRGLOCK)) != 0;
+}
+
+static void
+ao_flash_pecr_unlock(void)
+{
+       if (!ao_flash_pecr_is_locked())
+               return;
+
+       /* Unlock Data EEPROM and FLASH_PECR register */
+       stm_flash.pekeyr = STM_FLASH_PEKEYR_PEKEY1;
+       stm_flash.pekeyr = STM_FLASH_PEKEYR_PEKEY2;
+}
+
+static void
+ao_flash_pgr_unlock(void)
+{
+       if (!ao_flash_pgr_is_locked())
+               return;
+
+       /* Unlock program memory */
+       stm_flash.prgkeyr = STM_FLASH_PRGKEYR_PRGKEY1;
+       stm_flash.prgkeyr = STM_FLASH_PRGKEYR_PRGKEY2;
+}
+
+static void
+ao_flash_wait_bsy(void)
+{
+       while (stm_flash.sr & (1 << STM_FLASH_SR_BSY))
+               ;
+}
+
+static void
+ao_flash_erase_page(uint32_t *page)
+{
+       ao_flash_pecr_unlock();
+       ao_flash_pgr_unlock();
+
+       stm_flash.pecr |= (1 << STM_FLASH_PECR_ERASE);
+       stm_flash.pecr |= (1 << STM_FLASH_PECR_PROG);
+       
+       ao_flash_wait_bsy();
+
+       *page = 0x00000000;
+}
+
+static void __attribute__ ((section(".text.ram"), noinline))
+       _ao_flash_half_page(uint32_t *dst, uint32_t *src)
+{
+       uint8_t         i;
+
+       stm_flash.pecr |= (1 << STM_FLASH_PECR_FPRG);
+       stm_flash.pecr |= (1 << STM_FLASH_PECR_PROG);
+       while (stm_flash.sr & (1 << STM_FLASH_SR_BSY))
+               ;
+       
+       for (i = 0; i < 32; i++)
+               *dst++ = *src++;
+}
+
+void
+ao_flash_page(uint32_t *page, uint32_t *src)
+{
+       uint8_t         h;
+
+       ao_flash_erase_page(page);
+       for (h = 0; h < 2; h++) {
+               ao_flash_pecr_unlock();
+               ao_flash_pgr_unlock();
+               _ao_flash_half_page(page, src);
+               page += 32;
+               src += 32;
+       }
+}