Userspace may want to manually control when the data should go into
WriteBooster buffer. The control happens via "wb_on" node, but presently,
there is no simple way to check if WriteBooster is supported and
enabled.
Expose the Write Booster and Clock Scaling capabilities to be able to
determine if the Write Booster is available and if its manual control is
blocked by Clock Scaling mechanism.
Link: https://lore.kernel.org/r/20220829081845.v8.1.Ibf9efc9be50783eeee55befa2270b7d38552354c@changeid
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Daniil Lunev <dlunev@chromium.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
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 <avri.altman@wdc.com>
Signed-off-by: Jinyoung Choi <j-young.choi@samsung.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Mediatek UFS does not want to toggle write booster during clock scaling.
Permit host driver to disable wb toggling during clock scaling.
Introduce a flag UFSHCD_CAP_WB_WITH_CLK_SCALING to decouple WB and clock
scaling. UFSHCD_CAP_WB_WITH_CLK_SCALING is only valid when
UFSHCD_CAP_CLK_SCALING is set. Just like UFSHCD_CAP_HIBERN8_WITH_CLK_GATING
is valid only when UFSHCD_CAP_CLK_GATING set.
Set UFSHCD_CAP_WB_WITH_CLK_SCALING for qcom to compatible legacy design at
the same time.
Link: https://lore.kernel.org/r/20220804025422.18803-1-peter.wang@mediatek.com
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Peter Wang <peter.wang@mediatek.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
