[PATCH 3/5] bus: ti-sysc: Ignore clockactivity unless specified as a quirk

From: Tony Lindgren
Date: Sun May 31 2020 - 15:40:31 EST


We must ignore the clockactivity bit for most modules and not set it
unless specified for the module with SYSC_QUIRK_USE_CLOCKACT. Otherwise
the interface clock can be automatically gated constantly causing
unexpected performance issues.

Fixes: ae9ae12e9daa ("bus: ti-sysc: Handle clockactivity for enable and disable")
Cc: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
Cc: Tomi Valkeinen <tomi.valkeinen@xxxxxx>
Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx>
---
drivers/bus/ti-sysc.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/bus/ti-sysc.c b/drivers/bus/ti-sysc.c
--- a/drivers/bus/ti-sysc.c
+++ b/drivers/bus/ti-sysc.c
@@ -989,10 +989,13 @@ static int sysc_enable_module(struct device *dev)
regbits = ddata->cap->regbits;
reg = sysc_read(ddata, ddata->offsets[SYSC_SYSCONFIG]);

- /* Set CLOCKACTIVITY, we only use it for ick */
+ /*
+ * Set CLOCKACTIVITY, we only use it for ick. And we only configure it
+ * based on the SYSC_QUIRK_USE_CLOCKACT flag, not based on the hardware
+ * capabilities. See the old HWMOD_SET_DEFAULT_CLOCKACT flag.
+ */
if (regbits->clkact_shift >= 0 &&
- (ddata->cfg.quirks & SYSC_QUIRK_USE_CLOCKACT ||
- ddata->cfg.sysc_val & BIT(regbits->clkact_shift)))
+ (ddata->cfg.quirks & SYSC_QUIRK_USE_CLOCKACT))
reg |= SYSC_CLOCACT_ICK << regbits->clkact_shift;

/* Set SIDLE mode */
--
2.26.2