[PATCH v2 08/16] arm64: dts: mediatek: mt8192: Add mfg_ref_sel clock to MFG0 domain

AngeloGioacchino Del Regno posted 16 patches 1 year, 7 months ago
There is a newer version of this series
[PATCH v2 08/16] arm64: dts: mediatek: mt8192: Add mfg_ref_sel clock to MFG0 domain
Posted by AngeloGioacchino Del Regno 1 year, 7 months ago
The mfg_ref_sel clock is a mux used to switch between different "safe"
(and slower) clock sources for the GPU: this is used during MFGPLL
reconfiguration and eventually during idling at very low frequencies.

This clock getting turned off means that the GPU will occasionally be
unclocked, producing obvious consequences such as system crash or
unpredictable behavior: assigning it to the top level MFG power domain
will make sure that this stays on at all times during any operation on
the MFG domain (only GPU-related transactions).

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
---
 arch/arm64/boot/dts/mediatek/mt8192.dtsi | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/boot/dts/mediatek/mt8192.dtsi b/arch/arm64/boot/dts/mediatek/mt8192.dtsi
index 2a3606f68ae4..018d48f7d3c6 100644
--- a/arch/arm64/boot/dts/mediatek/mt8192.dtsi
+++ b/arch/arm64/boot/dts/mediatek/mt8192.dtsi
@@ -499,8 +499,9 @@ power-domain@MT8192_POWER_DOMAIN_CONN {
 
 				power-domain@MT8192_POWER_DOMAIN_MFG0 {
 					reg = <MT8192_POWER_DOMAIN_MFG0>;
-					clocks = <&topckgen CLK_TOP_MFG_PLL_SEL>;
-					clock-names = "mfg";
+					clocks = <&topckgen CLK_TOP_MFG_PLL_SEL>,
+						 <&topckgen CLK_TOP_MFG_REF_SEL>;
+					clock-names = "mfg", "alt";
 					#address-cells = <1>;
 					#size-cells = <0>;
 					#power-domain-cells = <1>;
-- 
2.39.2
Re: [PATCH v2 08/16] arm64: dts: mediatek: mt8192: Add mfg_ref_sel clock to MFG0 domain
Posted by Chen-Yu Tsai 1 year, 6 months ago
On Thu, Feb 23, 2023 at 9:44 PM AngeloGioacchino Del Regno
<angelogioacchino.delregno@collabora.com> wrote:
>
> The mfg_ref_sel clock is a mux used to switch between different "safe"
> (and slower) clock sources for the GPU: this is used during MFGPLL
> reconfiguration and eventually during idling at very low frequencies.
>
> This clock getting turned off means that the GPU will occasionally be
> unclocked, producing obvious consequences such as system crash or
> unpredictable behavior: assigning it to the top level MFG power domain
> will make sure that this stays on at all times during any operation on
> the MFG domain (only GPU-related transactions).
>
> Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>

Reviewed-by: Chen-Yu Tsai <wenst@chromium.org>