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7226b28ac7
Extend the TH1520 AON to describe the GPU clkgen reset line, required for proper GPU clock and reset sequencing. The T-HEAD TH1520 GPU requires coordinated management of two clocks (core and sys) and two resets (GPU core reset and GPU clkgen reset). Only the clkgen reset is exposed at the AON level, to support SoC specific initialization handled through a dedicated auxiliary power sequencing driver. The GPU core reset remains described in the GPU device node, as from the GPU driver's perspective, there is only a single reset line [1]. This follows upstream maintainers' recommendations [2] to abstract SoC specific details into the PM domain layer rather than exposing them to drivers directly. Link: https://lore.kernel.org/all/816db99d-7088-4c1a-af03-b9a825ac09dc@imgtec.com/ - [1] Link: https://lore.kernel.org/all/38d9650fc11a674c8b689d6bab937acf@kernel.org/ - [2] Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Drew Fustini <drew@pdp7.com> Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> Signed-off-by: Michal Wilczynski <m.wilczynski@samsung.com> Link: https://lore.kernel.org/r/20250623-apr_14_for_sending-v6-2-6583ce0f6c25@samsung.com Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
61 lines
1.5 KiB
YAML
61 lines
1.5 KiB
YAML
# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
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%YAML 1.2
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---
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$id: http://devicetree.org/schemas/firmware/thead,th1520-aon.yaml#
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$schema: http://devicetree.org/meta-schemas/core.yaml#
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title: T-HEAD TH1520 AON (Always-On) Firmware
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description: |
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The Always-On (AON) subsystem in the TH1520 SoC is responsible for managing
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low-power states, system wakeup events, and power management tasks. It is
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designed to operate independently in a dedicated power domain, allowing it to
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remain functional even during the SoC's deep sleep states.
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At the heart of the AON subsystem is the E902, a low-power core that executes
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firmware responsible for coordinating tasks such as power domain control,
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clock management, and system wakeup signaling. Communication between the main
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SoC and the AON subsystem is handled through a mailbox interface, which
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enables message-based interactions with the AON firmware.
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maintainers:
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- Michal Wilczynski <m.wilczynski@samsung.com>
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properties:
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compatible:
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const: thead,th1520-aon
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mboxes:
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maxItems: 1
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mbox-names:
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items:
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- const: aon
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resets:
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maxItems: 1
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reset-names:
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items:
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- const: gpu-clkgen
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"#power-domain-cells":
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const: 1
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required:
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- compatible
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- mboxes
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- mbox-names
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- "#power-domain-cells"
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additionalProperties: false
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examples:
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- |
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aon: aon {
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compatible = "thead,th1520-aon";
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mboxes = <&mbox_910t 1>;
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mbox-names = "aon";
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#power-domain-cells = <1>;
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};
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