#include <asm/msr.h>
#include <asm/u-boot-x86.h>
-#define MAX_NUM_FREQS 8
+#define MAX_NUM_FREQS 9
DECLARE_GLOBAL_DATA_PTR;
static struct freq_desc freq_desc_tables[] = {
/* PNW */
- { 6, 0x27, 0, { 0, 0, 0, 0, 0, 99840, 0, 83200 } },
+ { 6, 0x27, 0, { 0, 0, 0, 0, 0, 99840, 0, 83200, 0 } },
/* CLV+ */
- { 6, 0x35, 0, { 0, 133200, 0, 0, 0, 99840, 0, 83200 } },
+ { 6, 0x35, 0, { 0, 133200, 0, 0, 0, 99840, 0, 83200, 0 } },
/* TNG - Intel Atom processor Z3400 series */
- { 6, 0x4a, 1, { 0, 100000, 133300, 0, 0, 0, 0, 0 } },
+ { 6, 0x4a, 1, { 0, 100000, 133300, 0, 0, 0, 0, 0, 0 } },
/* VLV2 - Intel Atom processor E3000, Z3600, Z3700 series */
- { 6, 0x37, 1, { 83300, 100000, 133300, 116700, 80000, 0, 0, 0 } },
+ { 6, 0x37, 1, { 83300, 100000, 133300, 116700, 80000, 0, 0, 0, 0 } },
/* ANN - Intel Atom processor Z3500 series */
- { 6, 0x5a, 1, { 83300, 100000, 133300, 100000, 0, 0, 0, 0 } },
+ { 6, 0x5a, 1, { 83300, 100000, 133300, 100000, 0, 0, 0, 0, 0 } },
+ /* AMT - Intel Atom processor X7-Z8000 and X5-Z8000 series */
+ { 6, 0x4c, 1, { 83300, 100000, 133300, 116700,
+ 80000, 93300, 90000, 88900, 87500 } },
/* Ivybridge */
- { 6, 0x3a, 2, { 0, 0, 0, 0, 0, 0, 0, 0 } },
+ { 6, 0x3a, 2, { 0, 0, 0, 0, 0, 0, 0, 0, 0 } },
};
static int match_cpu(u8 family, u8 model)
(freq_desc_tables[cpu_index].freqs[freq_id])
/*
- * Do MSR calibration only for known/supported CPUs.
+ * TSC on Intel Atom SoCs capable of determining TSC frequency by MSR is
+ * reliable and the frequency is known (provided by HW).
*
- * Returns the calibration value or 0 if MSR calibration failed.
+ * On these platforms PIT/HPET is generally not available so calibration won't
+ * work at all and there is no other clocksource to act as a watchdog for the
+ * TSC, so we have no other choice than to trust it.
+ *
+ * Returns the TSC frequency in MHz or 0 if HW does not provide it.
*/
-static unsigned long __maybe_unused try_msr_calibrate_tsc(void)
+static unsigned long __maybe_unused cpu_mhz_from_msr(void)
{
u32 lo, hi, ratio, freq_id, freq;
unsigned long res;
return 0;
}
-static int tsc_timer_probe(struct udevice *dev)
+static void tsc_timer_ensure_setup(void)
{
- struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev);
-
+ if (gd->arch.tsc_base)
+ return;
gd->arch.tsc_base = rdtsc();
/*
* If there is no clock frequency specified in the device tree,
* calibrate it by ourselves.
*/
- if (!uc_priv->clock_rate) {
+ if (!gd->arch.clock_rate) {
unsigned long fast_calibrate;
- fast_calibrate = try_msr_calibrate_tsc();
+ fast_calibrate = cpu_mhz_from_msr();
if (!fast_calibrate) {
fast_calibrate = quick_pit_calibrate();
if (!fast_calibrate)
panic("TSC frequency is ZERO");
}
- uc_priv->clock_rate = fast_calibrate * 1000000;
+ gd->arch.clock_rate = fast_calibrate * 1000000;
}
+}
+
+static int tsc_timer_probe(struct udevice *dev)
+{
+ struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev);
+
+ tsc_timer_ensure_setup();
+ uc_priv->clock_rate = gd->arch.clock_rate;
return 0;
}
+unsigned long notrace timer_early_get_rate(void)
+{
+ tsc_timer_ensure_setup();
+
+ return gd->arch.clock_rate;
+}
+
+u64 notrace timer_early_get_count(void)
+{
+ return rdtsc() - gd->arch.tsc_base;
+}
+
static const struct timer_ops tsc_timer_ops = {
.get_count = tsc_timer_get_count,
};