From 86a44f045b8cbfd885b7425f4cd8a1c353593057 Mon Sep 17 00:00:00 2001 From: Bart Van Assche Date: Tue, 26 Jul 2022 15:52:21 -0700 Subject: [PATCH] scsi: ufs: core: Increase the maximum data buffer size Measurements for one particular UFS controller + UFS device show a 25% higher read bandwidth if the maximum data buffer size is increased from 512 KiB to 1 MiB. Hence increase the maximum size of the data buffer associated with a single request from SCSI_DEFAULT_MAX_SECTORS (1024) * 512 bytes = 512 KiB to 1 MiB. Notes: - The maximum data buffer size supported by the UFSHCI specification is 65535 * 256 KiB or about 16 GiB. - The maximum data buffer size for READ(10) commands is 65535 logical blocks. To transfer more than 65535 * 4096 bytes = 255 MiB with a single SCSI command, the READ(16) command is required. Support for READ(16) is optional in the UFS 3.1 and UFS 4.0 standards. Link: https://lore.kernel.org/r/20220726225232.1362251-1-bvanassche@acm.org Cc: Adrian Hunter Cc: Avri Altman Cc: Bean Huo Cc: Stanley Chu Tested-by: Avri Altman Acked-by: Avri Altman Signed-off-by: Bart Van Assche Signed-off-by: Martin K. Petersen --- drivers/ufs/core/ufshcd.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c index f4f8ded97ef2..dbe74f6b0c47 100644 --- a/drivers/ufs/core/ufshcd.c +++ b/drivers/ufs/core/ufshcd.c @@ -8304,6 +8304,7 @@ static struct scsi_host_template ufshcd_driver_template = { .cmd_per_lun = UFSHCD_CMD_PER_LUN, .can_queue = UFSHCD_CAN_QUEUE, .max_segment_size = PRDT_DATA_BYTE_COUNT_MAX, + .max_sectors = (1 << 20) / SECTOR_SIZE, /* 1 MiB */ .max_host_blocked = 1, .track_queue_depth = 1, .sdev_groups = ufshcd_driver_groups, -- 2.11.0