From ffe4e6ab42d2534302be825e49a2d085acf80f30 Mon Sep 17 00:00:00 2001 From: Caleb Connolly Date: Wed, 26 Mar 2025 13:24:09 +0100 Subject: [PATCH] scsi: sync cache on write We don't have a mechanism to safely shutdown block devices prior to a baord reset or driver removal. Prevent data loss by synchronizing the SCSI cache after every write. In particular this solves the issue of capsule updates looping on some devices because the board resets immediately after deleting the capsule file and this write wouldn't be flushed in time. This may impact NAND wear, but should be negligible given the usecases for disk write in U-Boot. Signed-off-by: Caleb Connolly Reviewed-by: Neil Armstrong --- drivers/scsi/scsi.c | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c index 34ac47c03ab..3e556540cae 100644 --- a/drivers/scsi/scsi.c +++ b/drivers/scsi/scsi.c @@ -78,6 +78,23 @@ static void scsi_setup_inquiry(struct scsi_cmd *pccb) pccb->msgout[0] = SCSI_IDENTIFY; /* NOT USED */ } +static void scsi_setup_sync_cache(struct scsi_cmd *pccb, lbaint_t start, + unsigned short blocks) +{ + pccb->cmd[0] = SCSI_SYNC_CACHE; + pccb->cmd[1] = 0; + pccb->cmd[2] = (unsigned char)(start >> 24) & 0xff; + pccb->cmd[3] = (unsigned char)(start >> 16) & 0xff; + pccb->cmd[4] = (unsigned char)(start >> 8) & 0xff; + pccb->cmd[5] = (unsigned char)start & 0xff; + pccb->cmd[6] = 0; + pccb->cmd[7] = (unsigned char)(blocks >> 8) & 0xff; + pccb->cmd[8] = (unsigned char)blocks & 0xff; + pccb->cmd[9] = 0; + pccb->cmdlen = 10; + pccb->msgout[0] = SCSI_IDENTIFY; /* NOT USED */ +} + static void scsi_setup_read_ext(struct scsi_cmd *pccb, lbaint_t start, unsigned short blocks) { @@ -240,6 +257,12 @@ static ulong scsi_write(struct udevice *dev, lbaint_t blknr, lbaint_t blkcnt, } buf_addr += pccb->datalen; } while (blks != 0); + + /* Flush the SCSI cache so we don't lose data on board reset. */ + scsi_setup_sync_cache(pccb, 0, 0); + if (scsi_exec(bdev, pccb)) + scsi_print_error(pccb); + debug("%s: end startblk " LBAF ", blccnt %x buffer %lX\n", __func__, start, smallblks, buf_addr); return blkcnt; -- 2.39.5