-/*
- * Copyright © 2009 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 "at45db161d.h"
-
-/* Total bytes of available storage */
-__pdata uint32_t ao_storage_total;
-
-/* Block size - device is erased in these units. At least 256 bytes */
-__pdata uint32_t ao_storage_block;
-
-/* Byte offset of config block. Will be ao_storage_block bytes long */
-__pdata uint32_t ao_storage_config;
-
-/* Storage unit size - device reads and writes must be within blocks of this size. Usually 256 bytes. */
-__pdata uint16_t ao_storage_unit;
-
-#define FLASH_CS P1_1
-#define FLASH_CS_INDEX 1
-
-#define FLASH_BLOCK_SIZE_MAX 512
-
-__xdata uint8_t ao_flash_mutex;
-
-#define ao_flash_delay() do { \
- _asm nop _endasm; \
- _asm nop _endasm; \
- _asm nop _endasm; \
-} while(0)
-
-#define ao_flash_cs_low() ao_spi_get_bit(FLASH_CS)
-
-#define ao_flash_cs_high() ao_spi_put_bit(FLASH_CS)
-
-struct ao_flash_instruction {
- uint8_t instruction;
- uint8_t address[3];
-} __xdata ao_flash_instruction;
-
-static void
-ao_flash_set_pagesize_512(void)
-{
- ao_flash_cs_low();
- ao_flash_instruction.instruction = FLASH_SET_CONFIG;
- ao_flash_instruction.address[0] = FLASH_SET_512_BYTE_0;
- ao_flash_instruction.address[1] = FLASH_SET_512_BYTE_1;
- ao_flash_instruction.address[2] = FLASH_SET_512_BYTE_2;
- ao_spi_send(&ao_flash_instruction, 4);
- ao_flash_cs_high();
-}
-
-
-static uint8_t
-ao_flash_read_status(void)
-{
- ao_flash_cs_low();
- ao_flash_instruction.instruction = FLASH_READ_STATUS;
- ao_spi_send(&ao_flash_instruction, 1);
- ao_spi_recv(&ao_flash_instruction, 1);
- ao_flash_cs_high();
- return ao_flash_instruction.instruction;
-}
-
-#define FLASH_BLOCK_NONE 0xffff
-
-static __xdata uint8_t ao_flash_data[FLASH_BLOCK_SIZE_MAX];
-static __pdata uint16_t ao_flash_block = FLASH_BLOCK_NONE;
-static __pdata uint8_t ao_flash_block_dirty;
-static __pdata uint8_t ao_flash_write_pending;
-static __pdata uint8_t ao_flash_setup_done;
-static __pdata uint8_t ao_flash_block_shift;
-static __pdata uint16_t ao_flash_block_size;
-static __pdata uint16_t ao_flash_block_mask;
-
-void
-ao_storage_setup(void) __reentrant
-{
- uint8_t status;
-
- if (ao_flash_setup_done)
- return;
-
- ao_mutex_get(&ao_flash_mutex);
- if (ao_flash_setup_done) {
- ao_mutex_put(&ao_flash_mutex);
- return;
- }
-
- /* On first use, check to see if the flash chip has
- * been programmed to use 512 byte pages. If not, do so.
- * And then, because the flash part must be power cycled
- * for that change to take effect, panic.
- */
- status = ao_flash_read_status();
-
- if (!(status & FLASH_STATUS_PAGESIZE_512)) {
- ao_flash_set_pagesize_512();
- ao_panic(AO_PANIC_FLASH);
- }
-
- switch (status & 0x3c) {
-
- /* AT45DB321D */
- case 0x34:
- ao_flash_block_shift = 9;
- ao_storage_total = ((uint32_t) 4 * (uint32_t) 1024 * (uint32_t) 1024);
- break;
-
- /* AT45DB161D */
- case 0x2c:
- ao_flash_block_shift = 9;
- ao_storage_total = ((uint32_t) 2 * (uint32_t) 1024 * (uint32_t) 1024);
- break;
-
- /* AT45DB081D */
- case 0x24:
- ao_flash_block_shift = 8;
- ao_storage_total = ((uint32_t) 1024 * (uint32_t) 1024);
- break;
-
- /* AT45DB041D */
- case 0x1c:
- ao_flash_block_shift = 8;
- ao_storage_total = ((uint32_t) 512 * (uint32_t) 1024);
- break;
-
- /* AT45DB021D */
- case 0x14:
- ao_flash_block_shift = 8;
- ao_storage_total = ((uint32_t) 256 * (uint32_t) 1024);
- break;
-
- /* AT45DB011D */
- case 0x0c:
- ao_flash_block_shift = 8;
- ao_storage_total = ((uint32_t) 128 * (uint32_t) 1024);
- break;
-
- default:
- ao_panic(AO_PANIC_FLASH);
- }
- ao_flash_block_size = 1 << ao_flash_block_shift;
- ao_flash_block_mask = ao_flash_block_size - 1;
-
- ao_storage_block = ao_flash_block_size;
- ao_storage_config = ao_storage_total - ao_storage_block;
- ao_storage_unit = ao_flash_block_size;
-
- ao_flash_setup_done = 1;
- ao_mutex_put(&ao_flash_mutex);
-}
-
-static void
-ao_flash_wait_write(void)
-{
- if (ao_flash_write_pending) {
- for (;;) {
- uint8_t status = ao_flash_read_status();
- if ((status & FLASH_STATUS_RDY))
- break;
- }
- ao_flash_write_pending = 0;
- }
-}
-
-/* Write the current block to the FLASHPROM */
-static void
-ao_flash_write_block(void)
-{
- ao_flash_wait_write();
- ao_flash_cs_low();
- ao_flash_instruction.instruction = FLASH_WRITE;
-
- /* 13/14 block bits + 9/8 byte bits (always 0) */
- ao_flash_instruction.address[0] = ao_flash_block >> (16 - ao_flash_block_shift);
- ao_flash_instruction.address[1] = ao_flash_block << (ao_flash_block_shift - 8);
- ao_flash_instruction.address[2] = 0;
- ao_spi_send(&ao_flash_instruction, 4);
- ao_spi_send(ao_flash_data, ao_storage_block);
- ao_flash_cs_high();
- ao_flash_write_pending = 1;
-}
-
-/* Read the current block from the FLASHPROM */
-static void
-ao_flash_read_block(void)
-{
- ao_flash_wait_write();
- ao_flash_cs_low();
- ao_flash_instruction.instruction = FLASH_READ;
-
- /* 13/14 block bits + 9/8 byte bits (always 0) */
- ao_flash_instruction.address[0] = ao_flash_block >> (16 - ao_flash_block_shift);
- ao_flash_instruction.address[1] = ao_flash_block << (ao_flash_block_shift - 8);
- ao_flash_instruction.address[2] = 0;
- ao_spi_send(&ao_flash_instruction, 4);
- ao_spi_recv(ao_flash_data, ao_flash_block_size);
- ao_flash_cs_high();
-}
-
-static void
-ao_flash_flush_internal(void)
-{
- if (ao_flash_block_dirty) {
- ao_flash_write_block();
- ao_flash_block_dirty = 0;
- }
-}
-
-static void
-ao_flash_fill(uint16_t block)
-{
- if (block != ao_flash_block) {
- ao_flash_flush_internal();
- ao_flash_block = block;
- ao_flash_read_block();
- }
-}
-
-uint8_t
-ao_storage_device_write(uint32_t pos, __xdata void *buf, uint16_t len) __reentrant
-{
- uint16_t block = (uint16_t) (pos >> ao_flash_block_shift);
-
- /* Transfer the data */
- ao_mutex_get(&ao_flash_mutex); {
- if (len != ao_flash_block_size)
- ao_flash_fill(block);
- else {
- ao_flash_flush_internal();
- ao_flash_block = block;
- }
- memcpy(ao_flash_data + (uint16_t) (pos & ao_flash_block_mask),
- buf,
- len);
- ao_flash_block_dirty = 1;
- } ao_mutex_put(&ao_flash_mutex);
- return 1;
-}
-
-uint8_t
-ao_storage_device_read(uint32_t pos, __xdata void *buf, uint16_t len) __reentrant
-{
- uint16_t block = (uint16_t) (pos >> ao_flash_block_shift);
-
- /* Transfer the data */
- ao_mutex_get(&ao_flash_mutex); {
- ao_flash_fill(block);
- memcpy(buf,
- ao_flash_data + (uint16_t) (pos & ao_flash_block_mask),
- len);
- } ao_mutex_put(&ao_flash_mutex);
- return 1;
-}
-
-void
-ao_storage_flush(void) __reentrant
-{
- ao_mutex_get(&ao_flash_mutex); {
- ao_flash_flush_internal();
- } ao_mutex_put(&ao_flash_mutex);
-}
-
-uint8_t
-ao_storage_erase(uint32_t pos) __reentrant
-{
- ao_mutex_get(&ao_flash_mutex); {
- ao_flash_flush_internal();
- ao_flash_block = (uint16_t) (pos >> ao_flash_block_shift);
- memset(ao_flash_data, 0xff, ao_flash_block_size);
- ao_flash_block_dirty = 1;
- } ao_mutex_put(&ao_flash_mutex);
- return 1;
-}
-
-void
-ao_storage_device_info(void) __reentrant
-{
- uint8_t status;
-
- ao_storage_setup();
- ao_mutex_get(&ao_flash_mutex); {
- status = ao_flash_read_status();
- printf ("Flash status: 0x%02x\n", status);
- printf ("Flash block shift: %d\n", ao_flash_block_shift);
- printf ("Flash block size: %d\n", ao_flash_block_size);
- printf ("Flash block mask: %d\n", ao_flash_block_mask);
- printf ("Flash device size: %ld\n", ao_storage_total);
- } ao_mutex_put(&ao_flash_mutex);
-}
-
-/*
- * To initialize the chip, set up the CS line and
- * the SPI interface
- */
-void
-ao_storage_device_init(void)
-{
- /* set up CS */
- FLASH_CS = 1;
- P1DIR |= (1 << FLASH_CS_INDEX);
- P1SEL &= ~(1 << FLASH_CS_INDEX);
-}