# sunxi-fel增加对16M以上Flash的支持 由于SPI flash 的地址是24bit，也就是最大16M 地址空间，所以对于32M flash，需要增加bank切换支持。 uboot中有CONFIG_SPI_FLASH_BAR选项可以使能bank切换。 但是sunxi-fel中尚未支持，所以下载的时候超出16M会循环覆盖掉。 这里介绍对sunxi-fel增加16M以上flash支持的方法。 ## u-boot的支持 drivers/mtd/spi/spi_flash.c ~~~ static int write_bar(struct spi_flash *flash, u32 offset) { u8 cmd, bank_sel; int ret; bank_sel = offset / (SPI_FLASH_16MB_BOUN << flash->shift); if (bank_sel == flash->bank_curr) goto bar_end; cmd = flash->bank_write_cmd; ret = spi_flash_write_common(flash, &cmd, 1, &bank_sel, 1); if (ret < 0) { debug("SF: fail to write bank register\n"); return ret; } bar_end: flash->bank_curr = bank_sel; return flash->bank_curr; } ~~~ ## sunxi-fel的支持 fel-spiflash.c ~~~ #define CMD_WRITE_ENABLE 0x06 #define SPI_FLASH_16MB_BOUN 0x1000000 # define CMD_BANKADDR_BRWR 0x17 //only SPANSION flash use it # define CMD_BANKADDR_BRRD 0x16 # define CMD_EXTNADDR_WREAR 0xC5 # define CMD_EXTNADDR_RDEAR 0xC8 size_t bank_curr = 0; void aw_fel_spiflash_write_helper(feldev_handle *dev, uint32_t offset, void *buf, size_t len, size_t erase_size, uint8_t erase_cmd, size_t program_size, uint8_t program_cmd) { uint8_t *buf8 = (uint8_t *)buf; size_t max_chunk_size = dev->soc_info->scratch_addr - dev->soc_info->spl_addr; size_t cmd_idx, bank_sel; if (max_chunk_size > 0x1000) max_chunk_size = 0x1000; uint8_t *cmdbuf = malloc(max_chunk_size); cmd_idx = 0; prepare_spi_batch_data_transfer(dev, dev->soc_info->spl_addr); //add bank support { cmd_idx = 0; bank_sel = offset /SPI_FLASH_16MB_BOUN; if (bank_sel == bank_curr) goto bar_end; /* Emit write enable command */ cmdbuf[cmd_idx++] = 0; cmdbuf[cmd_idx++] = 1; cmdbuf[cmd_idx++] = CMD_WRITE_ENABLE; /* Emit write bank */ cmdbuf[cmd_idx++] = 0; cmdbuf[cmd_idx++] = 2; cmdbuf[cmd_idx++] = CMD_EXTNADDR_WREAR; cmdbuf[cmd_idx++] = offset >> 24; /* Emit wait for completion */ cmdbuf[cmd_idx++] = 0xFF; cmdbuf[cmd_idx++] = 0xFF; /* Emit the end marker */ cmdbuf[cmd_idx++] = 0; cmdbuf[cmd_idx++] = 0; aw_fel_write(dev, cmdbuf, dev->soc_info->spl_addr, cmd_idx); aw_fel_remotefunc_execute(dev, NULL); bar_end: bank_curr = bank_sel; } cmd_idx = 0; ~~~ 重新编译sunxi-fel后就可以烧录32M flash了~