diff options
Diffstat (limited to 'firmware')
| -rw-r--r-- | firmware/target/arm/imx233/sdmmc-imx233.c | 120 |
1 files changed, 87 insertions, 33 deletions
diff --git a/firmware/target/arm/imx233/sdmmc-imx233.c b/firmware/target/arm/imx233/sdmmc-imx233.c index 72295bd313..e250662e2c 100644 --- a/firmware/target/arm/imx233/sdmmc-imx233.c +++ b/firmware/target/arm/imx233/sdmmc-imx233.c @@ -460,10 +460,43 @@ static int init_mmc_drive(int drive) } #endif +// low-level function, don't call directly! +static int __xfer_sectors(int drive, unsigned long start, int count, void *buf, bool read) +{ + uint32_t resp; + int ret = 0; + while(count != 0) + { + int this_count = MIN(count, IMX233_MAX_SINGLE_DMA_XFER_SIZE / 512); + /* Set bank_start to the correct unit (blocks or bytes). + * MMC drives use block addressing, SD cards bytes or blocks */ + int bank_start = start; + if(SDMMC_MODE(drive) == SD_MODE && !(SDMMC_INFO(drive).ocr & (1<<30))) /* not SDHC */ + bank_start *= SD_BLOCK_SIZE; + /* issue read/write + * NOTE: rely on SD_{READ,WRITE}_MULTIPLE_BLOCK=MMC_{READ,WRITE}_MULTIPLE_BLOCK */ + ret = imx233_ssp_sd_mmc_transfer(SDMMC_SSP(drive), + read ? SD_READ_MULTIPLE_BLOCK : SD_WRITE_MULTIPLE_BLOCK, + bank_start, SSP_SHORT_RESP, buf, this_count, false, read, &resp); + if(ret != SSP_SUCCESS) + break; + /* stop transmission + * NOTE: rely on SD_STOP_TRANSMISSION=MMC_STOP_TRANSMISSION */ + if(!send_cmd(drive, SD_STOP_TRANSMISSION, 0, MCI_RESP|MCI_BUSY, &resp)) + { + ret = -15; + break; + } + count -= this_count; + start += this_count; + buf += this_count * 512; + } + return ret; +} + static int transfer_sectors(int drive, unsigned long start, int count, void *buf, bool read) { int ret = 0; - uint32_t resp; /* update disk activity */ disk_last_activity[drive] = current_tick; @@ -488,7 +521,6 @@ static int transfer_sectors(int drive, unsigned long start, int count, void *buf ret = -201; goto Lend; } - /* select card. * NOTE: rely on SD_SELECT_CARD=MMC_SELECT_CARD */ if(!send_cmd(drive, SD_SELECT_CARD, SDMMC_RCA(drive), MCI_NO_RESP, NULL)) @@ -501,41 +533,63 @@ static int transfer_sectors(int drive, unsigned long start, int count, void *buf ret = wait_for_state(drive, SD_TRAN); if(ret < 0) goto Ldeselect; - while(count != 0) + + /** + * NOTE: we need to make sure dma transfers are aligned. This handled + * differently for read and write transfers. We do not repeat it each + * time but it should be noted that all transfers are limited by + * IMX233_MAX_SINGLE_DMA_XFER_SIZE and thus need to be split if needed. + * + * Read transfers: + * If the buffer is already aligned, transfer everything at once. + * Otherwise, transfer all sectors but one to the sub-buffer starting + * on the next cache ligned and then move the data. Then transfer the + * last sector to the aligned_buffer and then copy to the buffer. + * + * Write transfers: + * If the buffer is already aligned, transfer everything at once. + * Otherwise, copy the first sector to the aligned_buffer and transfer. + * Then move all other sectors within the buffer to make it cache + * aligned and transfer it. + */ + if(read) { - /* FIXME implement this_count > 1 by using a sub-buffer of [sub] that is - * cache-aligned and then moving the data when possible. This way we could - * transfer much greater amount of data at once */ - int this_count = 1; - /* Set bank_start to the correct unit (blocks or bytes). - * MMC drives use block addressing, SD cards bytes or blocks */ - int bank_start = start; - if(SDMMC_MODE(drive) == SD_MODE && !(SDMMC_INFO(drive).ocr & (1<<30))) /* not SDHC */ - bank_start *= SD_BLOCK_SIZE; - /* on write transfers, copy data to the aligned buffer */ - if(!read) - memcpy(aligned_buffer[drive], buf, 512); - /* issue read/write - * NOTE: rely on SD_{READ,WRITE}_MULTIPLE_BLOCK=MMC_{READ,WRITE}_MULTIPLE_BLOCK */ - ret = imx233_ssp_sd_mmc_transfer(SDMMC_SSP(drive), - read ? SD_READ_MULTIPLE_BLOCK : SD_WRITE_MULTIPLE_BLOCK, - bank_start, SSP_SHORT_RESP, aligned_buffer[drive], this_count, false, read, &resp); - if(ret != SSP_SUCCESS) - break; - /* stop transmission - * NOTE: rely on SD_STOP_TRANSMISSION=MMC_STOP_TRANSMISSION */ - if(!send_cmd(drive, SD_STOP_TRANSMISSION, 0, MCI_RESP|MCI_BUSY, &resp)) + void *ptr = CACHEALIGN_UP(buf); + if(buf != ptr) { - ret = -15; - break; + // copy count-1 sector and then move within the buffer + ret = __xfer_sectors(drive, start, count - 1, ptr, read); + memmove(buf, ptr, 512 * (count - 1)); + if(ret >= 0) + { + // transfer the last sector the aligned_buffer and copy + ret = __xfer_sectors(drive, start + count - 1, 1, + aligned_buffer[drive], read); + memcpy(buf + 512 * (count - 1), aligned_buffer[drive], 512); + } } - /* on read transfers, copy the data back to the user buffer */ - if(read) - memcpy(buf, aligned_buffer[drive], 512); - count -= this_count; - start += this_count; - buf += this_count * 512; + else + ret = __xfer_sectors(drive, start, count, buf, read); + } + else + { + void *ptr = CACHEALIGN_UP(buf); + if(buf != ptr) + { + // transfer the first sector to aligned_buffer and copy + memcpy(aligned_buffer[drive], buf, 512); + ret = __xfer_sectors(drive, start, 1, aligned_buffer[drive], read); + if(ret >= 0) + { + // move within the buffer and transfer + memmove(ptr, buf + 512, 512 * (count - 1)); + ret = __xfer_sectors(drive, start + 1, count - 1, ptr, read); + } + } + else + ret = __xfer_sectors(drive, start, count, buf, read); } + /* deselect card */ Ldeselect: /* CMD7 w/rca =0 : deselects card & puts it in STBY state |