Commit 920de6ebfab8 apparently exposed a latent bug, doorbell.access_width is initialized to 64, but per Lv Zheng, it should be 4, and indeed, making that change does bring pcc-cpufreq back to life.
Suggested-by: Lv Zheng <lv.zh...@intel.com> Signed-off-by: Mike Galbraith <umgwanakikb...@gmail.com> --- drivers/cpufreq/pcc-cpufreq.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/cpufreq/pcc-cpufreq.c +++ b/drivers/cpufreq/pcc-cpufreq.c @@ -487,7 +487,7 @@ static int __init pcc_cpufreq_probe(void doorbell.space_id = reg_resource->space_id; doorbell.bit_width = reg_resource->bit_width; doorbell.bit_offset = reg_resource->bit_offset; - doorbell.access_width = 64; + doorbell.access_width = 4; doorbell.address = reg_resource->address; pr_debug("probe: doorbell: space_id is %d, bit_width is %d, "