Damien George | 784e023 | 2017-01-24 16:56:03 +1100 | [diff] [blame^] | 1 | /* |
| 2 | * This file is part of the MicroPython project, http://micropython.org/ |
| 3 | * |
| 4 | * The MIT License (MIT) |
| 5 | * |
| 6 | * Copyright (c) 2016-2017 Damien P. George |
| 7 | * |
| 8 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
| 9 | * of this software and associated documentation files (the "Software"), to deal |
| 10 | * in the Software without restriction, including without limitation the rights |
| 11 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| 12 | * copies of the Software, and to permit persons to whom the Software is |
| 13 | * furnished to do so, subject to the following conditions: |
| 14 | * |
| 15 | * The above copyright notice and this permission notice shall be included in |
| 16 | * all copies or substantial portions of the Software. |
| 17 | * |
| 18 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| 19 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| 20 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| 21 | * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| 22 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| 23 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
| 24 | * THE SOFTWARE. |
| 25 | */ |
| 26 | |
| 27 | #include <stdio.h> |
| 28 | #include <string.h> |
| 29 | |
| 30 | #include "py/mperrno.h" |
| 31 | #include "py/mphal.h" |
| 32 | #include "extmod/machine_spi.h" |
| 33 | #include "drivers/memory/spiflash.h" |
| 34 | |
| 35 | #define CMD_WRITE (0x02) |
| 36 | #define CMD_READ (0x03) |
| 37 | #define CMD_WRDI (0x04) |
| 38 | #define CMD_RDSR (0x05) |
| 39 | #define CMD_WREN (0x06) |
| 40 | #define CMD_SEC_ERASE (0x20) |
| 41 | #define WAIT_SR_TIMEOUT (1000000) |
| 42 | |
| 43 | #define PAGE_SIZE (256) // maximum bytes we can write in one SPI transfer |
| 44 | #define SECTOR_SIZE (4096) // size of erase sector |
| 45 | |
| 46 | // Note: this code is not reentrant with this shared buffer |
| 47 | STATIC uint8_t buf[SECTOR_SIZE]; |
| 48 | |
| 49 | void mp_spiflash_init(mp_spiflash_t *self) { |
| 50 | mp_hal_pin_write(self->cs, 1); |
| 51 | mp_hal_pin_output(self->cs); |
| 52 | mp_hal_pin_write(self->spi.sck, 0); |
| 53 | mp_hal_pin_output(self->spi.sck); |
| 54 | mp_hal_pin_output(self->spi.mosi); |
| 55 | mp_hal_pin_input(self->spi.miso); |
| 56 | } |
| 57 | |
| 58 | STATIC void mp_spiflash_acquire_bus(mp_spiflash_t *self) { |
| 59 | // can be used for actions needed to acquire bus |
| 60 | (void)self; |
| 61 | } |
| 62 | |
| 63 | STATIC void mp_spiflash_release_bus(mp_spiflash_t *self) { |
| 64 | // can be used for actions needed to release bus |
| 65 | (void)self; |
| 66 | } |
| 67 | |
| 68 | STATIC void mp_spiflash_transfer(mp_spiflash_t *self, size_t len, const uint8_t *src, uint8_t *dest) { |
| 69 | mp_machine_soft_spi_transfer(&self->spi.base, len, src, dest); |
| 70 | } |
| 71 | |
| 72 | STATIC int mp_spiflash_wait_sr(mp_spiflash_t *self, uint8_t mask, uint8_t val, uint32_t timeout) { |
| 73 | uint8_t cmd[1] = {CMD_RDSR}; |
| 74 | mp_hal_pin_write(self->cs, 0); |
| 75 | mp_spiflash_transfer(self, 1, cmd, NULL); |
| 76 | for (; timeout; --timeout) { |
| 77 | mp_spiflash_transfer(self, 1, cmd, cmd); |
| 78 | if ((cmd[0] & mask) == val) { |
| 79 | break; |
| 80 | } |
| 81 | } |
| 82 | mp_hal_pin_write(self->cs, 1); |
| 83 | if ((cmd[0] & mask) == val) { |
| 84 | return 0; // success |
| 85 | } else if (timeout == 0) { |
| 86 | return -MP_ETIMEDOUT; |
| 87 | } else { |
| 88 | return -MP_EIO; |
| 89 | } |
| 90 | } |
| 91 | |
| 92 | STATIC int mp_spiflash_wait_wel1(mp_spiflash_t *self) { |
| 93 | return mp_spiflash_wait_sr(self, 2, 2, WAIT_SR_TIMEOUT); |
| 94 | } |
| 95 | |
| 96 | STATIC int mp_spiflash_wait_wip0(mp_spiflash_t *self) { |
| 97 | return mp_spiflash_wait_sr(self, 1, 0, WAIT_SR_TIMEOUT); |
| 98 | } |
| 99 | |
| 100 | STATIC void mp_spiflash_write_cmd(mp_spiflash_t *self, uint8_t cmd) { |
| 101 | mp_hal_pin_write(self->cs, 0); |
| 102 | mp_spiflash_transfer(self, 1, &cmd, NULL); |
| 103 | mp_hal_pin_write(self->cs, 1); |
| 104 | } |
| 105 | |
| 106 | STATIC int mp_spiflash_erase_sector(mp_spiflash_t *self, uint32_t addr) { |
| 107 | // enable writes |
| 108 | mp_spiflash_write_cmd(self, CMD_WREN); |
| 109 | |
| 110 | // wait WEL=1 |
| 111 | int ret = mp_spiflash_wait_wel1(self); |
| 112 | if (ret != 0) { |
| 113 | return ret; |
| 114 | } |
| 115 | |
| 116 | // erase the sector |
| 117 | mp_hal_pin_write(self->cs, 0); |
| 118 | uint8_t cmd[4] = {CMD_SEC_ERASE, addr >> 16, addr >> 8, addr}; |
| 119 | mp_spiflash_transfer(self, 4, cmd, NULL); |
| 120 | mp_hal_pin_write(self->cs, 1); |
| 121 | |
| 122 | // wait WIP=0 |
| 123 | return mp_spiflash_wait_wip0(self); |
| 124 | } |
| 125 | |
| 126 | STATIC int mp_spiflash_write_page(mp_spiflash_t *self, uint32_t addr, const uint8_t *src) { |
| 127 | // enable writes |
| 128 | mp_spiflash_write_cmd(self, CMD_WREN); |
| 129 | |
| 130 | // wait WEL=1 |
| 131 | int ret = mp_spiflash_wait_wel1(self); |
| 132 | if (ret != 0) { |
| 133 | return ret; |
| 134 | } |
| 135 | |
| 136 | // write the page |
| 137 | mp_hal_pin_write(self->cs, 0); |
| 138 | uint8_t cmd[4] = {CMD_WRITE, addr >> 16, addr >> 8, addr}; |
| 139 | mp_spiflash_transfer(self, 4, cmd, NULL); |
| 140 | mp_spiflash_transfer(self, PAGE_SIZE, src, NULL); |
| 141 | mp_hal_pin_write(self->cs, 1); |
| 142 | |
| 143 | // wait WIP=0 |
| 144 | return mp_spiflash_wait_wip0(self); |
| 145 | } |
| 146 | |
| 147 | void mp_spiflash_read(mp_spiflash_t *self, uint32_t addr, size_t len, uint8_t *dest) { |
| 148 | mp_spiflash_acquire_bus(self); |
| 149 | uint8_t cmd[4] = {CMD_READ, addr >> 16, addr >> 8, addr}; |
| 150 | mp_hal_pin_write(self->cs, 0); |
| 151 | mp_spiflash_transfer(self, 4, cmd, NULL); |
| 152 | mp_spiflash_transfer(self, len, dest, dest); |
| 153 | mp_hal_pin_write(self->cs, 1); |
| 154 | mp_spiflash_release_bus(self); |
| 155 | } |
| 156 | |
| 157 | int mp_spiflash_write(mp_spiflash_t *self, uint32_t addr, size_t len, const uint8_t *src) { |
| 158 | // TODO optimise so we don't need to erase multiple times for successive writes to a sector |
| 159 | |
| 160 | // align to 4096 sector |
| 161 | uint32_t offset = addr & 0xfff; |
| 162 | addr = (addr >> 12) << 12; |
| 163 | |
| 164 | // restriction for now, so we don't need to erase multiple pages |
| 165 | if (offset + len > sizeof(buf)) { |
| 166 | printf("mp_spiflash_write: len is too large\n"); |
| 167 | return -MP_EIO; |
| 168 | } |
| 169 | |
| 170 | mp_spiflash_acquire_bus(self); |
| 171 | |
| 172 | // read sector |
| 173 | uint8_t cmd[4] = {CMD_READ, addr >> 16, addr >> 8, addr}; |
| 174 | mp_hal_pin_write(self->cs, 0); |
| 175 | mp_spiflash_transfer(self, 4, cmd, NULL); |
| 176 | mp_spiflash_transfer(self, SECTOR_SIZE, buf, buf); |
| 177 | mp_hal_pin_write(self->cs, 1); |
| 178 | |
| 179 | // erase sector |
| 180 | int ret = mp_spiflash_erase_sector(self, addr); |
| 181 | if (ret != 0) { |
| 182 | mp_spiflash_release_bus(self); |
| 183 | return ret; |
| 184 | } |
| 185 | |
| 186 | // copy new block into buffer |
| 187 | memcpy(buf + offset, src, len); |
| 188 | |
| 189 | // write sector in pages of 256 bytes |
| 190 | for (int i = 0; i < SECTOR_SIZE; i += 256) { |
| 191 | ret = mp_spiflash_write_page(self, addr + i, buf + i); |
| 192 | if (ret != 0) { |
| 193 | mp_spiflash_release_bus(self); |
| 194 | return ret; |
| 195 | } |
| 196 | } |
| 197 | |
| 198 | mp_spiflash_release_bus(self); |
| 199 | return 0; // success |
| 200 | } |