In the Linux kernel, the following vulnerability has been resolved:
pmdomain: imx: Fix i.MX8MP VC8000E power up sequence
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.
[1] https://www.nxp.com/webapp/Download?colCode=IMX8MP_1P33A
References
- https://git.kernel.org/stable/c/25e252bcf1593b420b12a7231d9dd64b885a2ae2
- https://git.kernel.org/stable/c/4907f4c2d98b97e640191af5bcf2814ee1034b76
- https://git.kernel.org/stable/c/4ff3960f3527189bc115a927ed3561c758f562f1
- https://git.kernel.org/stable/c/87af3ebc112fb3f06753794390daf0f665f151b4
- https://git.kernel.org/stable/c/c498928f85651b56a4041ea165a22037eae69580