Lines Matching +full:clock +full:- +full:accuracy
1 // SPDX-License-Identifier: GPL-2.0
14 #include <asm/intel-family.h>
23 * lot of accuracy which leads to clock drift. As far as we know Bay Trail SoCs
26 * unclear if the root PLL outputs are used directly by the CPU clock PLL or
30 * So we can create a simplified model of the CPU clock setup using a reference
31 * clock of 100 MHz plus a quotient which gets us as close to the frequency
62 * Penwell and Clovertrail use spread spectrum clock,
161 * MSR-based CPU/TSC frequency discovery for certain CPUs.
179 freq_desc = (struct freq_desc *)id->driver_data; in cpu_khz_from_msr()
180 if (freq_desc->use_msr_plat) { in cpu_khz_from_msr()
190 index = lo & freq_desc->mask; in cpu_khz_from_msr()
191 md = &freq_desc->muldiv[index]; in cpu_khz_from_msr()
197 if (md->divider) { in cpu_khz_from_msr()
198 tscref = TSC_REFERENCE_KHZ * md->multiplier; in cpu_khz_from_msr()
199 freq = DIV_ROUND_CLOSEST(tscref, md->divider); in cpu_khz_from_msr()
202 * accuracy than just calculating freq * ratio. in cpu_khz_from_msr()
204 res = DIV_ROUND_CLOSEST(tscref * ratio, md->divider); in cpu_khz_from_msr()
206 freq = freq_desc->freqs[index]; in cpu_khz_from_msr()