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authorArtem Bityutskiy <artem.bityutskiy@linux.intel.com>2020-12-27 12:11:16 +0200
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2020-12-30 18:25:34 +0100
commit9cf93f056f783f986c19f40d5304d1bcffa0fc0d (patch)
treec7ed92783a6dc41a658e5bc32f98d730f1acb2f0 /drivers/idle
parent8b3fd902391fdee526f6ba46899a3f8005983ae1 (diff)
downloadlinux-9cf93f056f783f986c19f40d5304d1bcffa0fc0d.tar.bz2
intel_idle: add SnowRidge C-state table
Add C-state table for the SnowRidge SoC which is found on Intel Jacobsville platforms. The following has been changed. 1. C1E latency changed from 10us to 15us. It was measured using the open source "wult" tool (the "nic" method, 15us is the 99.99th percentile). 2. C1E power break even changed from 20us to 25us, which may result in less C1E residency in some workloads. 3. C6 latency changed from 50us to 130us. Measured the same way as C1E. The C6 C-state is supported only by some SnowRidge revisions, so add a C-state table commentary about this. On SnowRidge, C6 support is enumerated via the usual mechanism: "mwait" leaf of the "cpuid" instruction. The 'intel_idle' driver does check this leaf, so even though C6 is present in the table, the driver will only use it if the CPU does support it. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/idle')
-rw-r--r--drivers/idle/intel_idle.c41
1 files changed, 40 insertions, 1 deletions
diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c
index d79335506ecd..28f93b9aa51b 100644
--- a/drivers/idle/intel_idle.c
+++ b/drivers/idle/intel_idle.c
@@ -963,6 +963,39 @@ static struct cpuidle_state dnv_cstates[] __initdata = {
.enter = NULL }
};
+/*
+ * Note, depending on HW and FW revision, SnowRidge SoC may or may not support
+ * C6, and this is indicated in the CPUID mwait leaf.
+ */
+static struct cpuidle_state snr_cstates[] __initdata = {
+ {
+ .name = "C1",
+ .desc = "MWAIT 0x00",
+ .flags = MWAIT2flg(0x00),
+ .exit_latency = 2,
+ .target_residency = 2,
+ .enter = &intel_idle,
+ .enter_s2idle = intel_idle_s2idle, },
+ {
+ .name = "C1E",
+ .desc = "MWAIT 0x01",
+ .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
+ .exit_latency = 15,
+ .target_residency = 25,
+ .enter = &intel_idle,
+ .enter_s2idle = intel_idle_s2idle, },
+ {
+ .name = "C6",
+ .desc = "MWAIT 0x20",
+ .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
+ .exit_latency = 130,
+ .target_residency = 500,
+ .enter = &intel_idle,
+ .enter_s2idle = intel_idle_s2idle, },
+ {
+ .enter = NULL }
+};
+
static const struct idle_cpu idle_cpu_nehalem __initconst = {
.state_table = nehalem_cstates,
.auto_demotion_disable_flags = NHM_C1_AUTO_DEMOTE | NHM_C3_AUTO_DEMOTE,
@@ -1084,6 +1117,12 @@ static const struct idle_cpu idle_cpu_dnv __initconst = {
.use_acpi = true,
};
+static const struct idle_cpu idle_cpu_snr __initconst = {
+ .state_table = snr_cstates,
+ .disable_promotion_to_c1e = true,
+ .use_acpi = true,
+};
+
static const struct x86_cpu_id intel_idle_ids[] __initconst = {
X86_MATCH_INTEL_FAM6_MODEL(NEHALEM_EP, &idle_cpu_nhx),
X86_MATCH_INTEL_FAM6_MODEL(NEHALEM, &idle_cpu_nehalem),
@@ -1122,7 +1161,7 @@ static const struct x86_cpu_id intel_idle_ids[] __initconst = {
X86_MATCH_INTEL_FAM6_MODEL(ATOM_GOLDMONT, &idle_cpu_bxt),
X86_MATCH_INTEL_FAM6_MODEL(ATOM_GOLDMONT_PLUS, &idle_cpu_bxt),
X86_MATCH_INTEL_FAM6_MODEL(ATOM_GOLDMONT_D, &idle_cpu_dnv),
- X86_MATCH_INTEL_FAM6_MODEL(ATOM_TREMONT_D, &idle_cpu_dnv),
+ X86_MATCH_INTEL_FAM6_MODEL(ATOM_TREMONT_D, &idle_cpu_snr),
{}
};