iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

intel_idle: add BXT support

Browse Source 
Broxton has all the HSW C-states, except C3.
BXT C-state timing is slightly different.

Here we trust the IRTL MSRs as authority
on maximum C-state latency, and override the driver's tables
with the values found in the associated IRTL MSRs.
Further we set the target_residency to 1x maximum latency,
trusting the hardware demotion logic.

Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Len Brown 2016-04-06 17:00:47 -04:00 committed by Rafael J. Wysocki
parent c998c07836
commit 5dcef69486
2 changed files with 145 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
arch/x86/include/asm/msr-index.h
View File

@ -162,6 +162,14 @@
#define MSR_PKG_C9_RESIDENCY 0x00000631
#define MSR_PKG_C10_RESIDENCY 0x00000632
/* Interrupt Response Limit */
#define MSR_PKGC3_IRTL 0x0000060a
#define MSR_PKGC6_IRTL 0x0000060b
#define MSR_PKGC7_IRTL 0x0000060c
#define MSR_PKGC8_IRTL 0x00000633
#define MSR_PKGC9_IRTL 0x00000634
#define MSR_PKGC10_IRTL 0x00000635
/* Run Time Average Power Limiting (RAPL) Interface */
#define MSR_RAPL_POWER_UNIT 0x00000606

137
drivers/idle/intel_idle.c
View File

@ -766,6 +766,67 @@ static struct cpuidle_state knl_cstates[] = {
.enter = NULL }
};
static struct cpuidle_state bxt_cstates[] = {
{
.name = "C1-BXT",
.desc = "MWAIT 0x00",
.flags = MWAIT2flg(0x00),
.exit_latency = 2,
.target_residency = 2,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C1E-BXT",
.desc = "MWAIT 0x01",
.flags = MWAIT2flg(0x01),
.exit_latency = 10,
.target_residency = 20,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C6-BXT",
.desc = "MWAIT 0x20",
.flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
.exit_latency = 133,
.target_residency = 133,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C7s-BXT",
.desc = "MWAIT 0x31",
.flags = MWAIT2flg(0x31) | CPUIDLE_FLAG_TLB_FLUSHED,
.exit_latency = 155,
.target_residency = 155,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C8-BXT",
.desc = "MWAIT 0x40",
.flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED,
.exit_latency = 1000,
.target_residency = 1000,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C9-BXT",
.desc = "MWAIT 0x50",
.flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED,
.exit_latency = 2000,
.target_residency = 2000,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C10-BXT",
.desc = "MWAIT 0x60",
.flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
.exit_latency = 10000,
.target_residency = 10000,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.enter = NULL }
};
/**
* intel_idle
* @dev: cpuidle_device
@ -950,6 +1011,11 @@ static const struct idle_cpu idle_cpu_knl = {
.state_table = knl_cstates,
};
static const struct idle_cpu idle_cpu_bxt = {
.state_table = bxt_cstates,
.disable_promotion_to_c1e = true,
};
#define ICPU(model, cpu) \
{ X86_VENDOR_INTEL, 6, model, X86_FEATURE_MWAIT, (unsigned long)&cpu }
@ -985,6 +1051,7 @@ static const struct x86_cpu_id intel_idle_ids[] __initconst = {
ICPU(0x9e, idle_cpu_skl),
ICPU(0x55, idle_cpu_skx),
ICPU(0x57, idle_cpu_knl),
ICPU(0x5c, idle_cpu_bxt),
{}
};
MODULE_DEVICE_TABLE(x86cpu, intel_idle_ids);
@ -1075,6 +1142,73 @@ static void ivt_idle_state_table_update(void)
/* else, 1 and 2 socket systems use default ivt_cstates */
}
/*
* Translate IRTL (Interrupt Response Time Limit) MSR to usec
*/
static unsigned int irtl_ns_units[] = {
1, 32, 1024, 32768, 1048576, 33554432, 0, 0 };
static unsigned long long irtl_2_usec(unsigned long long irtl)
{
unsigned long long ns;
ns = irtl_ns_units[(irtl >> 10) & 0x3];
return div64_u64((irtl & 0x3FF) * ns, 1000);
}
/*
* bxt_idle_state_table_update(void)
*
* On BXT, we trust the IRTL to show the definitive maximum latency
* We use the same value for target_residency.
*/
static void bxt_idle_state_table_update(void)
{
unsigned long long msr;
rdmsrl(MSR_PKGC6_IRTL, msr);
if (msr) {
unsigned int usec = irtl_2_usec(msr);
bxt_cstates[2].exit_latency = usec;
bxt_cstates[2].target_residency = usec;
}
rdmsrl(MSR_PKGC7_IRTL, msr);
if (msr) {
unsigned int usec = irtl_2_usec(msr);
bxt_cstates[3].exit_latency = usec;
bxt_cstates[3].target_residency = usec;
}
rdmsrl(MSR_PKGC8_IRTL, msr);
if (msr) {
unsigned int usec = irtl_2_usec(msr);
bxt_cstates[4].exit_latency = usec;
bxt_cstates[4].target_residency = usec;
}
rdmsrl(MSR_PKGC9_IRTL, msr);
if (msr) {
unsigned int usec = irtl_2_usec(msr);
bxt_cstates[5].exit_latency = usec;
bxt_cstates[5].target_residency = usec;
}
rdmsrl(MSR_PKGC10_IRTL, msr);
if (msr) {
unsigned int usec = irtl_2_usec(msr);
bxt_cstates[6].exit_latency = usec;
bxt_cstates[6].target_residency = usec;
}
}
/*
* sklh_idle_state_table_update(void)
*
@ -1130,6 +1264,9 @@ static void intel_idle_state_table_update(void)
case 0x3e: /* IVT */
ivt_idle_state_table_update();
break;
case 0x5c: /* BXT */
bxt_idle_state_table_update();
break;
case 0x5e: /* SKL-H */
sklh_idle_state_table_update();
break;