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Subject: RE: [PATCH v3 1/2] PCI: dwc: Implement general suspend/resume
 functionality for L2/L3 transitions
Thread-Topic: [PATCH v3 1/2] PCI: dwc: Implement general suspend/resume
 functionality for L2/L3 transitions
Thread-Index: AQHZct3SW2dT9GmC60WQlV8ZXVruY69W24pA
Date:   Fri, 12 May 2023 14:47:46 +0000
Message-ID: <AM6PR04MB48383AB3FD2062334ECB66EB88759@AM6PR04MB4838.eurprd04.prod.outlook.com>
References: <20230419164118.596300-1-Frank.Li@nxp.com>
In-Reply-To: <20230419164118.596300-1-Frank.Li@nxp.com>
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>=20
> Introduced helper function dw_pcie_get_ltssm to retrieve
> SMLH_LTSS_STATE.
> Added API pme_turn_off and exit_from_l2 for managing L2/L3 state
> transitions.
>=20
> Typical L2 entry workflow:
>=20
> 1. Transmit PME turn off signal to PCI devices.
> 2. Await link entering L2_IDLE state.
> 3. Transition Root complex to D3 state.
>=20
> Typical L2 exit workflow:
>=20
> 1. Transition Root complex to D0 state.
> 2. Issue exit from L2 command.
> 3. Reinitialize PCI host.
> 4. Wait for link to become active.
>=20
> Signed-off-by: Frank Li <Frank.Li@nxp.com>
> ---

Ping

> Change from v2 to v3:
> - Basic rewrite whole patch according rob herry suggestion.
>   put common function into dwc, so more soc can share the same logic.
>=20