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, 0 insertions, 162 deletions

diff --git a/arch/mips/mti-malta/malta-smtc.c b/arch/mips/mti-malta/malta-smtc.c
deleted file mode 100644
index c484990..0000000
--- a/arch/mips/mti-malta/malta-smtc.c
+++ /dev/null
@@ -1,162 +0,0 @@
-/*
- * Malta Platform-specific hooks for SMP operation
- */
-#include <linux/irq.h>
-#include <linux/init.h>
-
-#include <asm/mipsregs.h>
-#include <asm/mipsmtregs.h>
-#include <asm/smtc.h>
-#include <asm/smtc_ipi.h>
-
-/* VPE/SMP Prototype implements platform interfaces directly */
-
-/*
- * Cause the specified action to be performed on a targeted "CPU"
- */
-
-static void msmtc_send_ipi_single(int cpu, unsigned int action)
-{
-	/* "CPU" may be TC of same VPE, VPE of same CPU, or different CPU */
-	smtc_send_ipi(cpu, LINUX_SMP_IPI, action);
-}
-
-static void msmtc_send_ipi_mask(const struct cpumask *mask, unsigned int action)
-{
-	unsigned int i;
-
-	for_each_cpu(i, mask)
-		msmtc_send_ipi_single(i, action);
-}
-
-/*
- * Post-config but pre-boot cleanup entry point
- */
-static void msmtc_init_secondary(void)
-{
-	int myvpe;
-
-	/* Don't enable Malta I/O interrupts (IP2) for secondary VPEs */
-	myvpe = read_c0_tcbind() & TCBIND_CURVPE;
-	if (myvpe != 0) {
-		/* Ideally, this should be done only once per VPE, but... */
-		clear_c0_status(ST0_IM);
-		set_c0_status((0x100 << cp0_compare_irq)
-				| (0x100 << MIPS_CPU_IPI_IRQ));
-		if (cp0_perfcount_irq >= 0)
-			set_c0_status(0x100 << cp0_perfcount_irq);
-	}
-
-	smtc_init_secondary();
-}
-
-/*
- * Platform "CPU" startup hook
- */
-static void msmtc_boot_secondary(int cpu, struct task_struct *idle)
-{
-	smtc_boot_secondary(cpu, idle);
-}
-
-/*
- * SMP initialization finalization entry point
- */
-static void msmtc_smp_finish(void)
-{
-	smtc_smp_finish();
-}
-
-/*
- * Hook for after all CPUs are online
- */
-
-static void msmtc_cpus_done(void)
-{
-}
-
-/*
- * Platform SMP pre-initialization
- *
- * As noted above, we can assume a single CPU for now
- * but it may be multithreaded.
- */
-
-static void __init msmtc_smp_setup(void)
-{
-	/*
-	 * we won't get the definitive value until
-	 * we've run smtc_prepare_cpus later, but
-	 * we would appear to need an upper bound now.
-	 */
-	smp_num_siblings = smtc_build_cpu_map(0);
-}
-
-static void __init msmtc_prepare_cpus(unsigned int max_cpus)
-{
-	smtc_prepare_cpus(max_cpus);
-}
-
-struct plat_smp_ops msmtc_smp_ops = {
-	.send_ipi_single	= msmtc_send_ipi_single,
-	.send_ipi_mask		= msmtc_send_ipi_mask,
-	.init_secondary		= msmtc_init_secondary,
-	.smp_finish		= msmtc_smp_finish,
-	.cpus_done		= msmtc_cpus_done,
-	.boot_secondary		= msmtc_boot_secondary,
-	.smp_setup		= msmtc_smp_setup,
-	.prepare_cpus		= msmtc_prepare_cpus,
-};
-
-#ifdef CONFIG_MIPS_MT_SMTC_IRQAFF
-/*
- * IRQ affinity hook
- */
-
-
-int plat_set_irq_affinity(struct irq_data *d, const struct cpumask *affinity,
-			  bool force)
-{
-	cpumask_t tmask;
-	int cpu = 0;
-	void smtc_set_irq_affinity(unsigned int irq, cpumask_t aff);
-
-	/*
-	 * On the legacy Malta development board, all I/O interrupts
-	 * are routed through the 8259 and combined in a single signal
-	 * to the CPU daughterboard, and on the CoreFPGA2/3 34K models,
-	 * that signal is brought to IP2 of both VPEs. To avoid racing
-	 * concurrent interrupt service events, IP2 is enabled only on
-	 * one VPE, by convention VPE0.	 So long as no bits are ever
-	 * cleared in the affinity mask, there will never be any
-	 * interrupt forwarding.  But as soon as a program or operator
-	 * sets affinity for one of the related IRQs, we need to make
-	 * sure that we don't ever try to forward across the VPE boundary,
-	 * at least not until we engineer a system where the interrupt
-	 * _ack() or _end() function can somehow know that it corresponds
-	 * to an interrupt taken on another VPE, and perform the appropriate
-	 * restoration of Status.IM state using MFTR/MTTR instead of the
-	 * normal local behavior. We also ensure that no attempt will
-	 * be made to forward to an offline "CPU".
-	 */
-
-	cpumask_copy(&tmask, affinity);
-	for_each_cpu(cpu, affinity) {
-		if ((cpu_data[cpu].vpe_id != 0) || !cpu_online(cpu))
-			cpu_clear(cpu, tmask);
-	}
-	cpumask_copy(d->affinity, &tmask);
-
-	if (cpus_empty(tmask))
-		/*
-		 * We could restore a default mask here, but the
-		 * runtime code can anyway deal with the null set
-		 */
-		printk(KERN_WARNING
-		       "IRQ affinity leaves no legal CPU for IRQ %d\n", d->irq);
-
-	/* Do any generic SMTC IRQ affinity setup */
-	smtc_set_irq_affinity(d->irq, tmask);
-
-	return IRQ_SET_MASK_OK_NOCOPY;
-}
-#endif /* CONFIG_MIPS_MT_SMTC_IRQAFF */