linux-kernel - [PATCH v4 2/8] clk: qcom: gdsc: Enable supply reglator in GPU GX handler

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Message-ID: <20240125-sa8295p-gpu-v4-2-7011c2a63037@quicinc.com>
Date: Thu, 25 Jan 2024 13:05:08 -0800
From: Bjorn Andersson <quic_bjorande@...cinc.com>
To: Bjorn Andersson <andersson@...nel.org>,
        Konrad Dybcio
	<konrad.dybcio@...aro.org>,
        Michael Turquette <mturquette@...libre.com>,
        Stephen Boyd <sboyd@...nel.org>, Rob Herring <robh+dt@...nel.org>,
        "Krzysztof
 Kozlowski" <krzysztof.kozlowski+dt@...aro.org>,
        Conor Dooley
	<conor+dt@...nel.org>,
        Taniya Das <quic_tdas@...cinc.com>,
        Johan Hovold
	<johan+linaro@...nel.org>
CC: <linux-arm-msm@...r.kernel.org>, <linux-clk@...r.kernel.org>,
        <devicetree@...r.kernel.org>, <linux-kernel@...r.kernel.org>,
        <linux-pm@...r.kernel.org>, <linux-arm-kernel@...ts.infradead.org>,
        "Bjorn
 Andersson" <quic_bjorande@...cinc.com>
Subject: [PATCH v4 2/8] clk: qcom: gdsc: Enable supply reglator in GPU GX
 handler

The GX GDSC is modelled to aid the GMU in powering down the GPU in the
event that the GPU crashes, so that it can be restarted again. But in
the event that the power-domain is supplied through a dedicated
regulator (in contrast to being a subdomin of another power-domain),
something needs to turn that regulator on, both to make sure things are
powered and to match the operation in gdsc_disable().

Reviewed-by: Konrad Dybcio <konrad.dybcio@...aro.org>
Signed-off-by: Bjorn Andersson <quic_bjorande@...cinc.com>
---
 drivers/clk/qcom/gdsc.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/drivers/clk/qcom/gdsc.c b/drivers/clk/qcom/gdsc.c
index 5358e28122ab..e7a4068b9f39 100644
--- a/drivers/clk/qcom/gdsc.c
+++ b/drivers/clk/qcom/gdsc.c
@@ -557,7 +557,15 @@ void gdsc_unregister(struct gdsc_desc *desc)
  */
 int gdsc_gx_do_nothing_enable(struct generic_pm_domain *domain)
 {
-	/* Do nothing but give genpd the impression that we were successful */
-	return 0;
+	struct gdsc *sc = domain_to_gdsc(domain);
+	int ret = 0;
+
+	/* Enable the parent supply, when controlled through the regulator framework. */
+	if (sc->rsupply)
+		ret = regulator_enable(sc->rsupply);
+
+	/* Do nothing with the GDSC itself */
+
+	return ret;
 }
 EXPORT_SYMBOL_GPL(gdsc_gx_do_nothing_enable);

-- 
2.25.1