From 475940cb8032c76622c64dd0bd30f31c0b0f6cf4 Mon Sep 17 00:00:00 2001 From: Keith Packard Date: Tue, 2 May 2017 11:35:18 -0700 Subject: [PATCH] altos/stmf0: Add code to use SoC flash as storage Signed-off-by: Keith Packard --- src/stmf0/ao_storage_stm.c | 191 +++++++++++++++++++++++++++++++++++++ 1 file changed, 191 insertions(+) create mode 100644 src/stmf0/ao_storage_stm.c diff --git a/src/stmf0/ao_storage_stm.c b/src/stmf0/ao_storage_stm.c new file mode 100644 index 00000000..1a6198a7 --- /dev/null +++ b/src/stmf0/ao_storage_stm.c @@ -0,0 +1,191 @@ +/* + * Copyright © 2017 Keith Packard + * + * 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. + */ + +#include +#include + +uint32_t ao_storage_block; +ao_pos_t ao_storage_total; +uint16_t ao_storage_unit; + +/* Note that the HSI clock must be running for this code to work. + * Also, special care must be taken with the linker to ensure that the + * functions marked 'ramtext' land in ram and not rom. An example of that + * can be found in altos-loader.ld + */ + +static uint8_t +ao_flash_is_locked(void) +{ + return (stm_flash.cr & (1 << STM_FLASH_CR_LOCK)) != 0; +} + +static void +ao_flash_unlock(void) +{ + if (!ao_flash_is_locked()) + return; + + /* Unlock FLASH_CR register */ + stm_flash.keyr = STM_FLASH_KEYR_KEY1; + stm_flash.keyr = STM_FLASH_KEYR_KEY2; + if (ao_flash_is_locked()) + ao_panic(AO_PANIC_FLASH); +} + +static void +ao_flash_lock(void) +{ + stm_flash.cr |= (1 << STM_FLASH_CR_LOCK); +} + +static uint32_t +stm_flash_page_size(void) +{ + uint16_t dev_id = stm_dev_id(); + + switch (dev_id) { + case 0x440: /* stm32f05x */ + case 0x444: /* stm32f03x */ + case 0x445: /* stm32f04x */ + return 1024; + case 0x442: /* stm32f09x */ + case 0x448: /* stm32f07x */ + return 2048; + } + ao_panic(AO_PANIC_FLASH); + return 0; +} + +#define ao_flash_wait_bsy() do { while (stm_flash.sr & (1 << STM_FLASH_SR_BSY)); } while (0) + +static void __attribute__ ((section(".ramtext"),noinline)) +_ao_flash_erase_page(uint16_t *page) +{ + stm_flash.cr |= (1 << STM_FLASH_CR_PER); + + stm_flash.ar = (uintptr_t) page; + + stm_flash.cr |= (1 << STM_FLASH_CR_STRT); + + ao_flash_wait_bsy(); + + stm_flash.cr &= ~(1 << STM_FLASH_CR_PER); +} + +#define _ao_flash_addr(pos) ((uint16_t *) (void *) ((uint8_t *) __flash__ + (pos))) + +static void __attribute ((section(".ramtext"), noinline)) _ao_flash_byte(uint32_t pos, uint8_t b) +{ + uint16_t v; + uint16_t *a = _ao_flash_addr(pos & ~1); + + if (pos & 1) + v = (*a & 0xff) | (b << 8); + else + v = (*a & 0xff00) | b; + *a = v; + ao_flash_wait_bsy(); +} + +static void __attribute__ ((section(".ramtext"), noinline)) +_ao_flash_write(uint32_t pos, void *sv, uint16_t len) +{ + uint8_t *s = sv; + uint16_t *f16; + uint16_t v; + + stm_flash.cr |= (1 << STM_FLASH_CR_PG); + + if (pos & 1) { + _ao_flash_byte(pos++, *s++); + len--; + } + f16 = _ao_flash_addr(pos); + while(len > 1) { + v = s[0] | (s[1] << 8); + s += 2; + *f16++ = v; + ao_flash_wait_bsy(); + len -= 2; + pos += 2; + } + if (len) + _ao_flash_byte(pos, *s++); + + stm_flash.cr &= ~(1 << STM_FLASH_CR_PG); +} + +uint8_t +ao_storage_erase(uint32_t pos) +{ + ao_arch_block_interrupts(); + ao_flash_unlock(); + + _ao_flash_erase_page(_ao_flash_addr(pos)); + + ao_flash_lock(); + ao_arch_release_interrupts(); + return 1; +} + +uint8_t +ao_storage_device_write(uint32_t pos, void *v, uint16_t len) +{ + if (len == 0) + return 1; + + ao_arch_block_interrupts(); + ao_flash_unlock(); + + _ao_flash_write(pos, v, len); + + ao_flash_lock(); + ao_arch_release_interrupts(); + return 1; +} + +uint8_t +ao_storage_device_read(uint32_t pos, __xdata void *d, uint16_t len) __reentrant +{ + if (pos >= ao_storage_total || pos + len > ao_storage_total) + return 0; + memcpy(d, _ao_flash_addr(pos), len); + return 1; +} + +void +ao_storage_flush(void) __reentrant +{ +} + +void +ao_storage_setup(void) +{ + ao_storage_block = stm_flash_page_size(); + ao_storage_total = ((uint8_t *) __flash_end__) - ((uint8_t *) __flash__); + ao_storage_unit = ao_storage_total; +} + +void +ao_storage_device_info(void) __reentrant +{ + printf ("Using internal flash, page %d bytes, total %d bytes\n", + ao_storage_block, ao_storage_total); +} + +void +ao_storage_device_init(void) +{ +} -- 2.30.2