From 6c4148ce7cc1d80cef60242a97b25c83c844e68c Mon Sep 17 00:00:00 2001 From: Jinyoung Choi Date: Thu, 4 Aug 2022 16:53:54 +0900 Subject: scsi: ufs: wb: Add explicit flush sysfs attribute There is the following quirk to bypass "WB Flush" in Write Booster. - UFSHCI_QUIRK_SKIP_MANUAL_WB_FLUSH_CTRL If this quirk is not set, there is no knob that can control "WB Flush". There are three flags that control Write Booster Feature: 1. WB ON/OFF 2. WB Hibern Flush ON/OFF (implicitly) 3. WB Flush ON/OFF (explicit) The sysfs attribute that controls the WB was implemented. (1) In the case of "Hibern Flush", it is always good to turn on. Control may not be required. (2) Finally, "Flush" may be necessary because the Auto-Hibern8 is not supported in a specific environment. So the sysfs attribute that controls this is necessary. (3) Link: https://lore.kernel.org/r/20220804075354epcms2p8c21c894b4e28840c5fc651875b7f435f@epcms2p8 Reviewed-by: Avri Altman Signed-off-by: Jinyoung Choi Signed-off-by: Martin K. Petersen --- Documentation/ABI/testing/sysfs-driver-ufs | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'Documentation') diff --git a/Documentation/ABI/testing/sysfs-driver-ufs b/Documentation/ABI/testing/sysfs-driver-ufs index 6b248abb1bd7..91de786f9a71 100644 --- a/Documentation/ABI/testing/sysfs-driver-ufs +++ b/Documentation/ABI/testing/sysfs-driver-ufs @@ -1417,6 +1417,15 @@ Description: This node is used to set or display whether UFS WriteBooster is platform that doesn't support UFSHCD_CAP_CLK_SCALING, we can disable/enable WriteBooster through this sysfs node. +What: /sys/bus/platform/drivers/ufshcd/*/enable_wb_buf_flush +What: /sys/bus/platform/devices/*.ufs/enable_wb_buf_flush +Date: July 2022 +Contact: Jinyoung Choi +Description: This entry shows the status of WriteBooster buffer flushing + and it can be used to enable or disable the flushing. + If flushing is enabled, the device executes the flush + operation when the command queue is empty. + What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/hpb_version What: /sys/bus/platform/devices/*.ufs/device_descriptor/hpb_version Date: June 2021 -- cgit v1.2.3