Re: [PATCH v2] pmdomain: imx: Fix i.MX8MP VC8000E power up sequence

[Daniel Baluta]

On 2/28/26 03:12, Peng Fan (OSS) wrote:
> From: Peng Fan <peng.fan@xxxxxxx>
>
> Per errata[1]:
> ERR050531: VPU_NOC power down handshake may hang during VC8000E/VPUMIX
> power up/down cycling.
> Description: VC8000E reset de-assertion edge and AXI clock may have a
> timing issue.
> Workaround: Set bit2 (vc8000e_clk_en) of BLK_CLK_EN_CSR to 0 to gate off
> both AXI clock and VC8000E clock sent to VC8000E and AXI clock sent to
> VPU_NOC m_v_2 interface during VC8000E power up(VC8000E reset is
> de-asserted by HW)
>
> Add a bool variable is_errata_err050531 in
> 'struct imx8m_blk_ctrl_domain_data' to represent whether the workaround
> is needed. If is_errata_err050531 is true, first clear the clk before
> powering up gpc, then enable the clk after powering up gpc.
>
> While at here, using imx8mm_vpu_power_notifier() is wrong, as it ungates
> the VPU clocks to provide the ADB clock, which is necessary on i.MX8MM,
> but on i.MX8MP there is a separate gate (bit 3) for the NoC. So add
> imx8mp_vpu_power_notifier() for i.MX8MP.
>
> [1] https://www.nxp.com/webapp/Download?colCode=IMX8MP_1P33A
>
Peng,

Is using imx8mm_vpu_power_notifier wrong no matter on the errata? If so, I think you should fix

that problem first, e.g create a separate patch that fixes the notifier and then add support for the errata. In the future, if the chips with the errata are deprecated we could only revert that given patch. thanks,

Daniel.