AMD Family 1Ah CPU needs a different COF(Core Operating Frequency) formula,
due to a change in the PStateDef MSR layout in AMD Family 1Ah.
In AMD Family 1Ah, Core current operating frequency in MHz is calculated as
follows:
CoreCOF = Core::X86::Msr::PStateDef[CpuFid[11:0]] * 5MHz
We introduce a helper amd_parse_freq() to parse cpu min/nominal/max core
frequency from PstateDef register, to replace the original macro FREQ(v).
amd_parse_freq() is declared as const, as it mainly consists of mathematical
conputation.
Signed-off-by: Penny Zheng <penny.zh...@amd.com>
---
v2 -> v3:
- new commit
---
v3 -> v4:
- introduce amd_parse_freq() and declare it as const
- express if-else-arry() as switch()
---
xen/arch/x86/cpu/amd.c | 43 +++++++++++++++++++++++++++++++++++-------
1 file changed, 36 insertions(+), 7 deletions(-)
diff --git a/xen/arch/x86/cpu/amd.c b/xen/arch/x86/cpu/amd.c
index ce4e1df710..f93dda927e 100644
--- a/xen/arch/x86/cpu/amd.c
+++ b/xen/arch/x86/cpu/amd.c
@@ -56,6 +56,9 @@ bool __initdata amd_virt_spec_ctrl;
static bool __read_mostly fam17_c6_disabled;
+static uint64_t attr_const amd_parse_freq(unsigned char c, uint64_t value);
+#define INVAL_FREQ_MHZ ~(uint64_t)0
+
static inline int rdmsr_amd_safe(unsigned int msr, unsigned int *lo,
unsigned int *hi)
{
@@ -570,12 +573,35 @@ static void amd_get_topology(struct cpuinfo_x86 *c)
: c->cpu_core_id);
}
+static uint64_t amd_parse_freq(unsigned char c, uint64_t value)
+{
+ uint64_t freq = INVAL_FREQ_MHZ;
+
+ switch (c) {
+ case 0x10 ... 0x16:
+ freq = (((value & 0x3f) + 0x10) * 100) >> ((value >> 6) & 7);
+ break;
+ case 0x17 ... 0x19:
+ freq = ((value & 0xff) * 25 * 8) / ((value >> 8) & 0x3f);
+ break;
+ case 0x1A:
+ freq = (value & 0xfff) * 5;
+ break;
+ default:
+ printk(XENLOG_ERR
+ "Unsupported cpu familly %c on cpufreq parsing", c);
+ break;
+ }
+
+ return freq;
+}
+
void amd_log_freq(const struct cpuinfo_x86 *c)
{
unsigned int idx = 0, h;
uint64_t hi, lo, val;
- if (c->x86 < 0x10 || c->x86 > 0x19 ||
+ if (c->x86 < 0x10 || c->x86 > 0x1A ||
(c != &boot_cpu_data &&
(!opt_cpu_info || (c->apicid & (c->x86_num_siblings - 1)))))
return;
@@ -656,19 +682,22 @@ void amd_log_freq(const struct cpuinfo_x86 *c)
if (!(lo >> 63))
return;
-#define FREQ(v) (c->x86 < 0x17 ? ((((v) & 0x3f) + 0x10) * 100) >> (((v) >> 6)
& 7) \
- : (((v) & 0xff) * 25 * 8) / (((v) >> 8) &
0x3f))
if (idx && idx < h &&
!rdmsr_safe(0xC0010064 + idx, val) && (val >> 63) &&
!rdmsr_safe(0xC0010064, hi) && (hi >> 63))
printk("CPU%u: %lu (%lu ... %lu) MHz\n",
- smp_processor_id(), FREQ(val), FREQ(lo), FREQ(hi));
+ smp_processor_id(),
+ amd_parse_freq(c->x86, val),
+ amd_parse_freq(c->x86, lo),
+ amd_parse_freq(c->x86, hi));
else if (h && !rdmsr_safe(0xC0010064, hi) && (hi >> 63))
printk("CPU%u: %lu ... %lu MHz\n",
- smp_processor_id(), FREQ(lo), FREQ(hi));
+ smp_processor_id(),
+ amd_parse_freq(c->x86, lo),
+ amd_parse_freq(c->x86, hi));
else
- printk("CPU%u: %lu MHz\n", smp_processor_id(), FREQ(lo));
-#undef FREQ
+ printk("CPU%u: %lu MHz\n", smp_processor_id(),
+ amd_parse_freq(c->x86, lo));
}
void cf_check early_init_amd(struct cpuinfo_x86 *c)
--
2.34.1
