Re: [PATCH] clk: qcom: gcc-x1e80100: Keep GCC USB QTB clock always ON

[Bjorn Andersson <andersson@kernel.org>]

On Mon, Mar 23, 2026 at 10:26:53AM +0530, Jagadeesh Kona wrote:
> 
> 
> On 3/16/2026 6:26 PM, Dmitry Baryshkov wrote:
> > On Mon, Mar 16, 2026 at 04:38:21PM +0530, Jagadeesh Kona wrote:
> >> Keep GCC USB QTB clock always ON which is required for SMMU
> >> invalidation on X1E80100 platform.
> >>
> >> Signed-off-by: Jagadeesh Kona <jagadeesh.kona@oss.qualcomm.com>
> >> ---
> >>  drivers/clk/qcom/gcc-x1e80100.c | 1 +
> >>  1 file changed, 1 insertion(+)
> >>
> >> diff --git a/drivers/clk/qcom/gcc-x1e80100.c b/drivers/clk/qcom/gcc-x1e80100.c
> >> index 74afd12c158c01c121d9aecd56e65c0c302d7cd0..73a2a5112623e5190f41129af7fd76a86603557b 100644
> >> --- a/drivers/clk/qcom/gcc-x1e80100.c
> >> +++ b/drivers/clk/qcom/gcc-x1e80100.c
> >> @@ -7480,6 +7480,7 @@ static int gcc_x1e80100_probe(struct platform_device *pdev)
> >>  	qcom_branch_set_clk_en(regmap, 0x32004); /* GCC_VIDEO_AHB_CLK */
> >>  	qcom_branch_set_clk_en(regmap, 0x32030); /* GCC_VIDEO_XO_CLK */
> >>  	qcom_branch_set_clk_en(regmap, 0x71004); /* GCC_GPU_CFG_AHB_CLK */
> >> +	qcom_branch_set_clk_en(regmap, 0x7d01c); /* GCC_HLOS1_VOTE_AGGRE_NOC_MMU_USB_QTB_CLK */
> > 
> > Is it used during all SMMU invalidations or only for those related to
> > the USB controller?
> > 
> 
> Yes, it is required for all SMMU invalidations.

What happens if it's not enabled? Why isn't problem described in the
commit message?

If it is _required_, wouldn't that imply that this fixes a problem, and
if so, why isn't there a Fixes: tag?

Regards,
Bjorn

> 
> Thanks,
> Jagadeesh
> 
> >>  
> >>  	/* Clear GDSC_SLEEP_ENA_VOTE to stop votes being auto-removed in sleep. */
> >>  	regmap_write(regmap, 0x52224, 0x0);
> >>
> >> ---
> >> base-commit: b84a0ebe421ca56995ff78b66307667b62b3a900
> >> change-id: 20260316-hamoa-usb-qtb-clk-always-on-bcd4e5f3553e
> >>
> >> Best regards,
> >> -- 
> >> Jagadeesh Kona <jagadeesh.kona@oss.qualcomm.com>
> >>
> > 
>