Re: [PATCH 04/19] cpufreq: amd: introduce a new amd pstate driver to support future processors
From: Peter Zijlstra <peterz@infradead.org>
Date: 2021-09-09 15:05:30
Also in:
lkml
From: Peter Zijlstra <peterz@infradead.org>
Date: 2021-09-09 15:05:30
Also in:
lkml
On Wed, Sep 08, 2021 at 10:59:46PM +0800, Huang Rui wrote:
+static int pstate_init_perf(struct amd_cpudata *cpudata)
+{
+ u64 cap1;
+
+ int ret = rdmsrl_safe_on_cpu(cpudata->cpu, MSR_AMD_CPPC_CAP1,
+ &cap1);
+ if (ret)
+ return ret;
+
+ /* Some AMD processors has specific power features that the cppc entry
+ * doesn't indicate the highest performance. It will introduce the
+ * feature in following days.
+ */Wrong comment style; also imagine reading this comment half a year from now...
+ WRITE_ONCE(cpudata->highest_perf, amd_get_highest_perf()); + + WRITE_ONCE(cpudata->nominal_perf, CAP1_NOMINAL_PERF(cap1)); + WRITE_ONCE(cpudata->lowest_nonlinear_perf, CAP1_LOWNONLIN_PERF(cap1)); + WRITE_ONCE(cpudata->lowest_perf, CAP1_LOWEST_PERF(cap1)); + + return 0; +}