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authorTakashi Iwai <tiwai@suse.de>2019-02-08 14:20:32 +0100
committerTakashi Iwai <tiwai@suse.de>2019-02-08 14:20:32 +0100
commitd02cac152c97dffcb0cdd91e09b54fd6e2cca63d (patch)
tree68e4c6bd842703009f3edbf8f0e0e9326e4b2fad /arch/x86/kernel/tsc.c
parent36e4617c01153757cde9e5fcd375a75a8f8425c3 (diff)
parenta50e32694fbcdbf55875095258b9398e2eabd71f (diff)
Merge tag 'asoc-v5.1' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-next
ASoC: Updates for v5.1 Lots and lots of new drivers so far, a highlight being the MediaTek BTCVSD which is a driver for a Bluetooth radio chip - the first such driver we've had upstream. Hopefully we will soon also see a baseband with an upstream driver! - Support for only powering up channels that are actively being used. - Quite a few improvements to simplify the generic card drivers, especially the merge of the SCU cards into the main generic drivers. - Lots of fixes for probing on Intel systems, trying to rationalize things to look more standard from a framework point of view. - New drivers for Asahi Kasei Microdevices AK4497, Cirrus Logic CS4341, Google ChromeOS embedded controllers, Ingenic JZ4725B, MediaTek BTCVSD, MT8183 and MT6358, NXP MICFIL, Rockchip RK3328, Spreadtrum DMA controllers, Qualcomm WCD9335, Xilinx S/PDIF and PCM formatters.
Diffstat (limited to 'arch/x86/kernel/tsc.c')
-rw-r--r--arch/x86/kernel/tsc.c30
1 files changed, 16 insertions, 14 deletions
diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index e9f777bfed404..3fae238340699 100644
--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c
@@ -297,15 +297,16 @@ static int __init tsc_setup(char *str)
__setup("tsc=", tsc_setup);
-#define MAX_RETRIES 5
-#define SMI_TRESHOLD 50000
+#define MAX_RETRIES 5
+#define TSC_DEFAULT_THRESHOLD 0x20000
/*
- * Read TSC and the reference counters. Take care of SMI disturbance
+ * Read TSC and the reference counters. Take care of any disturbances
*/
static u64 tsc_read_refs(u64 *p, int hpet)
{
u64 t1, t2;
+ u64 thresh = tsc_khz ? tsc_khz >> 5 : TSC_DEFAULT_THRESHOLD;
int i;
for (i = 0; i < MAX_RETRIES; i++) {
@@ -315,7 +316,7 @@ static u64 tsc_read_refs(u64 *p, int hpet)
else
*p = acpi_pm_read_early();
t2 = get_cycles();
- if ((t2 - t1) < SMI_TRESHOLD)
+ if ((t2 - t1) < thresh)
return t2;
}
return ULLONG_MAX;
@@ -703,15 +704,15 @@ static unsigned long pit_hpet_ptimer_calibrate_cpu(void)
* zero. In each wait loop iteration we read the TSC and check
* the delta to the previous read. We keep track of the min
* and max values of that delta. The delta is mostly defined
- * by the IO time of the PIT access, so we can detect when a
- * SMI/SMM disturbance happened between the two reads. If the
+ * by the IO time of the PIT access, so we can detect when
+ * any disturbance happened between the two reads. If the
* maximum time is significantly larger than the minimum time,
* then we discard the result and have another try.
*
* 2) Reference counter. If available we use the HPET or the
* PMTIMER as a reference to check the sanity of that value.
* We use separate TSC readouts and check inside of the
- * reference read for a SMI/SMM disturbance. We dicard
+ * reference read for any possible disturbance. We dicard
* disturbed values here as well. We do that around the PIT
* calibration delay loop as we have to wait for a certain
* amount of time anyway.
@@ -744,7 +745,7 @@ static unsigned long pit_hpet_ptimer_calibrate_cpu(void)
if (ref1 == ref2)
continue;
- /* Check, whether the sampling was disturbed by an SMI */
+ /* Check, whether the sampling was disturbed */
if (tsc1 == ULLONG_MAX || tsc2 == ULLONG_MAX)
continue;
@@ -1268,7 +1269,7 @@ static DECLARE_DELAYED_WORK(tsc_irqwork, tsc_refine_calibration_work);
*/
static void tsc_refine_calibration_work(struct work_struct *work)
{
- static u64 tsc_start = -1, ref_start;
+ static u64 tsc_start = ULLONG_MAX, ref_start;
static int hpet;
u64 tsc_stop, ref_stop, delta;
unsigned long freq;
@@ -1283,14 +1284,15 @@ static void tsc_refine_calibration_work(struct work_struct *work)
* delayed the first time we expire. So set the workqueue
* again once we know timers are working.
*/
- if (tsc_start == -1) {
+ if (tsc_start == ULLONG_MAX) {
+restart:
/*
* Only set hpet once, to avoid mixing hardware
* if the hpet becomes enabled later.
*/
hpet = is_hpet_enabled();
- schedule_delayed_work(&tsc_irqwork, HZ);
tsc_start = tsc_read_refs(&ref_start, hpet);
+ schedule_delayed_work(&tsc_irqwork, HZ);
return;
}
@@ -1300,9 +1302,9 @@ static void tsc_refine_calibration_work(struct work_struct *work)
if (ref_start == ref_stop)
goto out;
- /* Check, whether the sampling was disturbed by an SMI */
- if (tsc_start == ULLONG_MAX || tsc_stop == ULLONG_MAX)
- goto out;
+ /* Check, whether the sampling was disturbed */
+ if (tsc_stop == ULLONG_MAX)
+ goto restart;
delta = tsc_stop - tsc_start;
delta *= 1000000LL;