cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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mtk-gce.txt (3144B)

      1MediaTek GCE
      2===============
      3
      4The Global Command Engine (GCE) is used to help read/write registers with
      5critical time limitation, such as updating display configuration during the
      6vblank. The GCE can be used to implement the Command Queue (CMDQ) driver.
      7
      8CMDQ driver uses mailbox framework for communication. Please refer to
      9mailbox.txt for generic information about mailbox device-tree bindings.
     10
     11Required properties:
     12- compatible: can be "mediatek,mt8173-gce", "mediatek,mt8183-gce",
     13  "mediatek,mt8186-gce", "mediatek,mt8192-gce", "mediatek,mt8195-gce" or
     14  "mediatek,mt6779-gce".
     15- reg: Address range of the GCE unit
     16- interrupts: The interrupt signal from the GCE block
     17- clock: Clocks according to the common clock binding
     18- clock-names: Must be "gce" to stand for GCE clock
     19- #mbox-cells: Should be 2.
     20	<&phandle channel priority>
     21	phandle: Label name of a gce node.
     22	channel: Channel of mailbox. Be equal to the thread id of GCE.
     23	priority: Priority of GCE thread.
     24
     25Required properties for a client device:
     26- mboxes: Client use mailbox to communicate with GCE, it should have this
     27  property and list of phandle, mailbox specifiers.
     28Optional properties for a client device:
     29- mediatek,gce-client-reg: Specify the sub-system id which is corresponding
     30  to the register address, it should have this property and list of phandle,
     31  sub-system specifiers.
     32  <&phandle subsys_number start_offset size>
     33  phandle: Label name of a gce node.
     34  subsys_number: specify the sub-system id which is corresponding
     35                 to the register address.
     36  start_offset: the start offset of register address that GCE can access.
     37  size: the total size of register address that GCE can access.
     38
     39Optional properties for a client mutex node:
     40- mediatek,gce-events: GCE events used by clients. The event numbers are
     41  defined in 'dt-bindings/gce/<chip>-gce.h'.
     42
     43Some vaules of properties are defined in 'dt-bindings/gce/mt8173-gce.h',
     44'dt-bindings/gce/mt8183-gce.h', 'dt-bindings/gce/mt8186-gce.h'
     45'dt-bindings/gce/mt8192-gce.h', 'dt-bindings/gce/mt8195-gce.h' or
     46'dt-bindings/gce/mt6779-gce.h'.
     47Such as sub-system ids, thread priority, event ids.
     48
     49Example:
     50
     51	gce: gce@10212000 {
     52		compatible = "mediatek,mt8173-gce";
     53		reg = <0 0x10212000 0 0x1000>;
     54		interrupts = <GIC_SPI 135 IRQ_TYPE_LEVEL_LOW>;
     55		clocks = <&infracfg CLK_INFRA_GCE>;
     56		clock-names = "gce";
     57		#mbox-cells = <2>;
     58	};
     59
     60Example for a client device:
     61
     62	mmsys: clock-controller@14000000 {
     63		compatible = "mediatek,mt8173-mmsys";
     64		mboxes = <&gce 0 CMDQ_THR_PRIO_LOWEST>,
     65			 <&gce 1 CMDQ_THR_PRIO_LOWEST>;
     66		mutex-event-eof = <CMDQ_EVENT_MUTEX0_STREAM_EOF
     67				CMDQ_EVENT_MUTEX1_STREAM_EOF>;
     68		mediatek,gce-client-reg = <&gce SUBSYS_1400XXXX 0x3000 0x1000>,
     69					  <&gce SUBSYS_1401XXXX 0x2000 0x100>;
     70		...
     71	};
     72
     73Example for a client mutex node:
     74	mutex: mutex@14020000 {
     75		compatible = "mediatek,mt8173-disp-mutex";
     76		reg = <0 0x14020000 0 0x1000>;
     77		interrupts = <GIC_SPI 169 IRQ_TYPE_LEVEL_LOW>;
     78		power-domains = <&scpsys MT8173_POWER_DOMAIN_MM>;
     79		clocks = <&mmsys CLK_MM_MUTEX_32K>;
     80		mediatek,gce-events = <CMDQ_EVENT_MUTEX0_STREAM_EOF>,
     81				      <CMDQ_EVENT_MUTEX1_STREAM_EOF>;
     82	};