The msm-rng driver is currently broken on MSM8916. The first issue is that the core clock isn't defined and thus not being enabled before registers in the PRNG block are accessed.
The second issue is that the enable method is only initializing the PRNG registers if the block is *already* initialized. This would have likely caused issues elsewhere once the driver was in more active use, but the problems on MSM8916 are immediate: trying to modify the state of LFSR_CFG causes SErrors, presumably because this register is protected by TZ. I also included a couple of extra patches while I'm in the neighborhood. One is to improve the logging in apq8016 clk_enable (which would have better surfaced the first issue). The other changes msm-rng driver slightly to only enable its core clock when it's needed (similar to how the kernel does it). Signed-off-by: Sam Day <m...@samcday.com> --- Changes in v2: - split hunk changing clk_ens of existing clocks into separate patch - Link to v1: https://lore.kernel.org/r/20250127-msm-rng-fixes-v1-0-00f5d2284...@samcday.com --- Sam Day (5): clk/qcom: apq8016: use BIT macro for clk en_vals clk/qcom: apq8016: add PRNG_AHB_CLK rng: msm: don't enable PRNG if it's already enabled clk/qcom: apq8016: improve clk_enable logging rng: msm: keep core clock disabled when PRNG not in use drivers/clk/qcom/clock-apq8016.c | 9 +++++---- drivers/rng/msm_rng.c | 13 +++++++++++-- 2 files changed, 16 insertions(+), 6 deletions(-) --- base-commit: 636fcc96c3d7e2b00c843e6da78ed3e9e3bdf4de change-id: 20250126-msm-rng-fixes-f5a722a9492c Best regards, -- Sam Day <m...@samcday.com>
