MIPS: MT: Remove SMTC support

Nobody is maintaining SMTC anymore and there also seems to be no userbase.
Which is a pity - the SMTC technology primarily developed by Kevin D.
Kissell <kevink@paralogos.com> is an ingenious demonstration for the MT
ASE's power and elegance.

Based on Markos Chandras <Markos.Chandras@imgtec.com> patch
https://patchwork.linux-mips.org/patch/6719/ which while very similar did
no longer apply cleanly when I tried to merge it plus some additional
post-SMTC cleanup - SMTC was a feature as tricky to remove as it was to
merge once upon a time.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 4 insertions, 45 deletions

diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 45e75b6173b5..e3f040cbaff3 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -1852,7 +1852,7 @@ config FORCE_MAX_ZONEORDER
 
 config CEVT_GIC
 	bool "Use GIC global counter for clock events"
-	depends on IRQ_GIC && !(MIPS_SEAD3 || MIPS_MT_SMTC)
+	depends on IRQ_GIC && !MIPS_SEAD3
 	help
 	  Use the GIC global counter for the clock events. The R4K clock
 	  event driver is always present, so if the platform ends up not
@@ -1936,24 +1936,6 @@ config MIPS_MT_SMP
 	  Intel Hyperthreading feature. For further information go to
 	  <http://www.imgtec.com/mips/mips-multithreading.asp>.
 
-config MIPS_MT_SMTC
-	bool "Use all TCs on all VPEs for SMP (DEPRECATED)"
-	depends on CPU_MIPS32_R2
-	depends on SYS_SUPPORTS_MULTITHREADING
-	depends on !MIPS_CPS
-	select CPU_MIPSR2_IRQ_VI
-	select CPU_MIPSR2_IRQ_EI
-	select MIPS_MT
-	select SMP
-	select SMP_UP
-	select SYS_SUPPORTS_SMP
-	select NR_CPUS_DEFAULT_8
-	help
-	  This is a kernel model which is known as SMTC. This is
-	  supported on cores with the MT ASE and presents all TCs
-	  available on all VPEs to support SMP. For further
-	  information see <http://www.linux-mips.org/wiki/34K#SMTC>.
-
 endchoice
 
 config MIPS_MT
@@ -1977,7 +1959,7 @@ config SYS_SUPPORTS_MULTITHREADING
 config MIPS_MT_FPAFF
 	bool "Dynamic FPU affinity for FP-intensive threads"
 	default y
-	depends on MIPS_MT_SMP || MIPS_MT_SMTC
+	depends on MIPS_MT_SMP
 
 config MIPS_VPE_LOADER
 	bool "VPE loader support."
@@ -1999,29 +1981,6 @@ config MIPS_VPE_LOADER_MT
 	default "y"
 	depends on MIPS_VPE_LOADER && !MIPS_CMP
 
-config MIPS_MT_SMTC_IM_BACKSTOP
-	bool "Use per-TC register bits as backstop for inhibited IM bits"
-	depends on MIPS_MT_SMTC
-	default n
-	help
-	  To support multiple TC microthreads acting as "CPUs" within
-	  a VPE, VPE-wide interrupt mask bits must be specially manipulated
-	  during interrupt handling. To support legacy drivers and interrupt
-	  controller management code, SMTC has a "backstop" to track and
-	  if necessary restore the interrupt mask. This has some performance
-	  impact on interrupt service overhead.
-
-config MIPS_MT_SMTC_IRQAFF
-	bool "Support IRQ affinity API"
-	depends on MIPS_MT_SMTC
-	default n
-	help
-	  Enables SMP IRQ affinity API (/proc/irq/*/smp_affinity, etc.)
-	  for SMTC Linux kernel. Requires platform support, of which
-	  an example can be found in the MIPS kernel i8259 and Malta
-	  platform code.  Adds some overhead to interrupt dispatch, and
-	  should be used only if you know what you are doing.
-
 config MIPS_VPE_LOADER_TOM
 	bool "Load VPE program into memory hidden from linux"
 	depends on MIPS_VPE_LOADER
@@ -2049,7 +2008,7 @@ config MIPS_VPE_APSP_API_MT
 
 config MIPS_CMP
 	bool "MIPS CMP framework support (DEPRECATED)"
-	depends on SYS_SUPPORTS_MIPS_CMP && !MIPS_MT_SMTC
+	depends on SYS_SUPPORTS_MIPS_CMP
 	select MIPS_GIC_IPI
 	select SYNC_R4K
 	select WEAK_ORDERING
@@ -2256,7 +2215,7 @@ config NODES_SHIFT
 
 config HW_PERF_EVENTS
 	bool "Enable hardware performance counter support for perf events"
-	depends on PERF_EVENTS && !MIPS_MT_SMTC && OPROFILE=n && (CPU_MIPS32 || CPU_MIPS64 || CPU_R10000 || CPU_SB1 || CPU_CAVIUM_OCTEON || CPU_XLP)
+	depends on PERF_EVENTS && OPROFILE=n && (CPU_MIPS32 || CPU_MIPS64 || CPU_R10000 || CPU_SB1 || CPU_CAVIUM_OCTEON || CPU_XLP)
 	default y
 	help
 	  Enable hardware performance counter support for perf events. If