git.gag.com Git - fw/altos/blob - src/stm/ao_flash_stm.c

   1 /*
   2  * Copyright © 2013 Keith Packard <keithp@keithp.com>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; version 2 of the License.
   7  *
   8  * This program is distributed in the hope that it will be useful, but
   9  * WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along
  14  * with this program; if not, write to the Free Software Foundation, Inc.,
  15  * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  16  */
  17
  18 #include <ao.h>
  19 #include <ao_flash_stm.h>
  20
  21 static uint8_t
  22 ao_flash_pecr_is_locked(void)
  23 {
  24         return (stm_flash.pecr & (1 << STM_FLASH_PECR_PELOCK)) != 0;
  25 }
  26
  27 static uint8_t
  28 ao_flash_pgr_is_locked(void)
  29 {
  30         return (stm_flash.pecr & (1 << STM_FLASH_PECR_PRGLOCK)) != 0;
  31 }
  32
  33 static void
  34 ao_flash_pecr_unlock(void)
  35 {
  36         if (!ao_flash_pecr_is_locked())
  37                 return;
  38
  39         /* Unlock Data EEPROM and FLASH_PECR register */
  40         stm_flash.pekeyr = STM_FLASH_PEKEYR_PEKEY1;
  41         stm_flash.pekeyr = STM_FLASH_PEKEYR_PEKEY2;
  42 }
  43
  44 static void
  45 ao_flash_pgr_unlock(void)
  46 {
  47         if (!ao_flash_pgr_is_locked())
  48                 return;
  49
  50         /* Unlock program memory */
  51         stm_flash.prgkeyr = STM_FLASH_PRGKEYR_PRGKEY1;
  52         stm_flash.prgkeyr = STM_FLASH_PRGKEYR_PRGKEY2;
  53 }
  54
  55 static void
  56 ao_flash_wait_bsy(void)
  57 {
  58         while (stm_flash.sr & (1 << STM_FLASH_SR_BSY))
  59                 ;
  60 }
  61
  62 static void
  63 ao_flash_erase_page(uint32_t *page)
  64 {
  65         ao_flash_pecr_unlock();
  66         ao_flash_pgr_unlock();
  67
  68         stm_flash.pecr |= (1 << STM_FLASH_PECR_ERASE);
  69         stm_flash.pecr |= (1 << STM_FLASH_PECR_PROG);
  70
  71         ao_flash_wait_bsy();
  72
  73         *page = 0x00000000;
  74 }
  75
  76 static void __attribute__ ((section(".text.ram"), noinline))
  77         _ao_flash_half_page(uint32_t *dst, uint32_t *src)
  78 {
  79         uint8_t         i;
  80
  81         stm_flash.pecr |= (1 << STM_FLASH_PECR_FPRG);
  82         stm_flash.pecr |= (1 << STM_FLASH_PECR_PROG);
  83         while (stm_flash.sr & (1 << STM_FLASH_SR_BSY))
  84                 ;
  85
  86         for (i = 0; i < 32; i++)
  87                 *dst++ = *src++;
  88 }
  89
  90 void
  91 ao_flash_page(uint32_t *page, uint32_t *src)
  92 {
  93         uint8_t         h;
  94
  95         ao_flash_erase_page(page);
  96         for (h = 0; h < 2; h++) {
  97                 ao_flash_pecr_unlock();
  98                 ao_flash_pgr_unlock();
  99                 _ao_flash_half_page(page, src);
 100                 page += 32;
 101                 src += 32;
 102         }
 103 }