cpu/x86/tsc: Flip and rename TSC_CONSTANT_RATE to UNKNOWN_TSC_RATE

The x86 timers are a bit of a mess. Cases where different stages use
different counters and timestamps use different counters from udelays.

The original intention was to only flip TSC_CONSTANT_RATE Kconfig
to NOT_CONSTANT_TSC_RATE. The name would be incorrect though, those
counters do run with a constant rate but we just lack tsc_freq_mhz()
implementation for three platforms.

Note that for boards with UNKNOWN_TSC_RATE=y, each stage will have a
slow run of calibrate_tsc_with_pit(). This is easy enough to fix with
followup implementation of tsc_freq_mhz() for the platforms.

Implementations with LAPIC_MONOTONIC_TIMER typically will not have
tsc_freq_mhz() implemented and default to UNKNOWN_TSC_RATE. However,
as they don't use TSC for udelay() the slow calibrate_tsc_with_pit()
is avoided.

Because x86/tsc_delay.tsc was using two different guards and nb/via/vx900
claimed UDELAY_TSC, but pulled UDELAY_IO implementation, we also switch
that romstage to use UDELAY_TSC.

Change-Id: I1690cb80295d6b006b75ed69edea28899b674b68
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/33928
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>

10 files changed, 1 insertions, 9 deletions

diff --git a/src/cpu/intel/fsp_model_406dx/Kconfig b/src/cpu/intel/fsp_model_406dx/Kconfig
index 77ba0bdb98..3e71469947 100644
--- a/src/cpu/intel/fsp_model_406dx/Kconfig
+++ b/src/cpu/intel/fsp_model_406dx/Kconfig
@@ -32,7 +32,6 @@ config CPU_SPECIFIC_OPTIONS
 	select PARALLEL_CPU_INIT
 	select TSC_SYNC_MFENCE
 	select TSC_MONOTONIC_TIMER
-	select TSC_CONSTANT_RATE
 	select CPU_INTEL_COMMON
 	select CPU_INTEL_COMMON_TIMEBASE
 	select NO_SMM
diff --git a/src/cpu/intel/haswell/Kconfig b/src/cpu/intel/haswell/Kconfig
index db119a05cc..d8d8b97004 100644
--- a/src/cpu/intel/haswell/Kconfig
+++ b/src/cpu/intel/haswell/Kconfig
@@ -14,7 +14,6 @@ config CPU_SPECIFIC_OPTIONS
 	select MMX
 	select SSE2
 	select UDELAY_TSC
-	select TSC_CONSTANT_RATE
 	select TSC_MONOTONIC_TIMER
 	select SUPPORT_CPU_UCODE_IN_CBFS
 	#select AP_IN_SIPI_WAIT
diff --git a/src/cpu/intel/model_1067x/Kconfig b/src/cpu/intel/model_1067x/Kconfig
index 16bc03b076..564a428bbc 100644
--- a/src/cpu/intel/model_1067x/Kconfig
+++ b/src/cpu/intel/model_1067x/Kconfig
@@ -7,7 +7,6 @@ config CPU_INTEL_MODEL_1067X
 	select SMP
 	select SSE2
 	select UDELAY_TSC
-	select TSC_CONSTANT_RATE
 	select TSC_MONOTONIC_TIMER
 	select TSC_SYNC_MFENCE
 	select SUPPORT_CPU_UCODE_IN_CBFS
diff --git a/src/cpu/intel/model_106cx/Kconfig b/src/cpu/intel/model_106cx/Kconfig
index 43c4048786..1ba8894940 100644
--- a/src/cpu/intel/model_106cx/Kconfig
+++ b/src/cpu/intel/model_106cx/Kconfig
@@ -7,7 +7,6 @@ config CPU_INTEL_MODEL_106CX
 	select SMP
 	select SSE2
 	select UDELAY_TSC
-	select TSC_CONSTANT_RATE
 	select TSC_MONOTONIC_TIMER
 	select SIPI_VECTOR_IN_ROM
 	select AP_IN_SIPI_WAIT
diff --git a/src/cpu/intel/model_2065x/Kconfig b/src/cpu/intel/model_2065x/Kconfig
index 572751186e..a76a95dc6d 100644
--- a/src/cpu/intel/model_2065x/Kconfig
+++ b/src/cpu/intel/model_2065x/Kconfig
@@ -12,7 +12,6 @@ config CPU_SPECIFIC_OPTIONS
 	select SMP
 	select SSE2
 	select UDELAY_TSC
-	select TSC_CONSTANT_RATE
 	select TSC_MONOTONIC_TIMER
 	select SUPPORT_CPU_UCODE_IN_CBFS
 	select PARALLEL_CPU_INIT
diff --git a/src/cpu/intel/model_206ax/Kconfig b/src/cpu/intel/model_206ax/Kconfig
index 97d8d3d0d6..8dae6ecc30 100644
--- a/src/cpu/intel/model_206ax/Kconfig
+++ b/src/cpu/intel/model_206ax/Kconfig
@@ -13,7 +13,6 @@ config CPU_SPECIFIC_OPTIONS
 	select MMX
 	select SSE2
 	select UDELAY_TSC
-	select TSC_CONSTANT_RATE
 	select TSC_MONOTONIC_TIMER
 	select SUPPORT_CPU_UCODE_IN_CBFS
 	#select AP_IN_SIPI_WAIT
diff --git a/src/cpu/intel/model_6ex/Kconfig b/src/cpu/intel/model_6ex/Kconfig
index ff16724651..3af52722f3 100644
--- a/src/cpu/intel/model_6ex/Kconfig
+++ b/src/cpu/intel/model_6ex/Kconfig
@@ -7,7 +7,6 @@ config CPU_INTEL_MODEL_6EX
 	select SMP
 	select SSE2
 	select UDELAY_TSC
-	select TSC_CONSTANT_RATE
 	select TSC_MONOTONIC_TIMER
 	select AP_IN_SIPI_WAIT
 	select TSC_SYNC_MFENCE
diff --git a/src/cpu/intel/model_6fx/Kconfig b/src/cpu/intel/model_6fx/Kconfig
index e6c82564c9..cfd3e7c6e0 100644
--- a/src/cpu/intel/model_6fx/Kconfig
+++ b/src/cpu/intel/model_6fx/Kconfig
@@ -7,7 +7,6 @@ config CPU_INTEL_MODEL_6FX
 	select SMP
 	select SSE2
 	select UDELAY_TSC
-	select TSC_CONSTANT_RATE
 	select TSC_MONOTONIC_TIMER
 	select AP_IN_SIPI_WAIT
 	select TSC_SYNC_MFENCE
diff --git a/src/cpu/intel/slot_1/Kconfig b/src/cpu/intel/slot_1/Kconfig
index d9324944da..3d0522a09d 100644
--- a/src/cpu/intel/slot_1/Kconfig
+++ b/src/cpu/intel/slot_1/Kconfig
@@ -25,6 +25,7 @@ config SLOT_SPECIFIC_OPTIONS # dummy
 	select CPU_INTEL_MODEL_6XX
 	select NO_SMM
 	select NO_MONOTONIC_TIMER
+	select UNKNOWN_TSC_RATE
 
 config DCACHE_RAM_BASE
 	hex
diff --git a/src/cpu/intel/socket_mPGA604/Kconfig b/src/cpu/intel/socket_mPGA604/Kconfig
index 4ec46e0ac8..a2ebeb2325 100644
--- a/src/cpu/intel/socket_mPGA604/Kconfig
+++ b/src/cpu/intel/socket_mPGA604/Kconfig
@@ -9,7 +9,6 @@ config SOCKET_SPECIFIC_OPTIONS # dummy
 	select MMX
 	select SSE
 	select UDELAY_TSC
-	select TSC_CONSTANT_RATE
 	select TSC_MONOTONIC_TIMER
 	select SIPI_VECTOR_IN_ROM
 	select C_ENVIRONMENT_BOOTBLOCK