1 files changed, 316 insertions, 0 deletions
diff --git a/arch/mips/kernel/mips-mt.c b/arch/mips/kernel/mips-mt.c
new file mode 100644
index 000000000..efaa25276
--- /dev/null
+++ b/arch/mips/kernel/mips-mt.c
@@ -0,0 +1,316 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * General MIPS MT support routines, usable in AP/SP and SMVP.
+ * Copyright (C) 2005 Mips Technologies, Inc
+ */
+
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/export.h>
+#include <linux/interrupt.h>
+#include <linux/security.h>
+
+#include <asm/cpu.h>
+#include <asm/processor.h>
+#include <linux/atomic.h>
+#include <asm/hardirq.h>
+#include <asm/mmu_context.h>
+#include <asm/mipsmtregs.h>
+#include <asm/r4kcache.h>
+#include <asm/cacheflush.h>
+
+int vpelimit;
+
+static int __init maxvpes(char *str)
+{
+	get_option(&str, &vpelimit);
+
+	return 1;
+}
+
+__setup("maxvpes=", maxvpes);
+
+int tclimit;
+
+static int __init maxtcs(char *str)
+{
+	get_option(&str, &tclimit);
+
+	return 1;
+}
+
+__setup("maxtcs=", maxtcs);
+
+/*
+ * Dump new MIPS MT state for the core. Does not leave TCs halted.
+ * Takes an argument which taken to be a pre-call MVPControl value.
+ */
+
+void mips_mt_regdump(unsigned long mvpctl)
+{
+	unsigned long flags;
+	unsigned long vpflags;
+	unsigned long mvpconf0;
+	int nvpe;
+	int ntc;
+	int i;
+	int tc;
+	unsigned long haltval;
+	unsigned long tcstatval;
+
+	local_irq_save(flags);
+	vpflags = dvpe();
+	printk("=== MIPS MT State Dump ===\n");
+	printk("-- Global State --\n");
+	printk("   MVPControl Passed: %08lx\n", mvpctl);
+	printk("   MVPControl Read: %08lx\n", vpflags);
+	printk("   MVPConf0 : %08lx\n", (mvpconf0 = read_c0_mvpconf0()));
+	nvpe = ((mvpconf0 & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT) + 1;
+	ntc = ((mvpconf0 & MVPCONF0_PTC) >> MVPCONF0_PTC_SHIFT) + 1;
+	printk("-- per-VPE State --\n");
+	for (i = 0; i < nvpe; i++) {
+		for (tc = 0; tc < ntc; tc++) {
+			settc(tc);
+			if ((read_tc_c0_tcbind() & TCBIND_CURVPE) == i) {
+				printk("  VPE %d\n", i);
+				printk("   VPEControl : %08lx\n",
+				       read_vpe_c0_vpecontrol());
+				printk("   VPEConf0 : %08lx\n",
+				       read_vpe_c0_vpeconf0());
+				printk("   VPE%d.Status : %08lx\n",
+				       i, read_vpe_c0_status());
+				printk("   VPE%d.EPC : %08lx %pS\n",
+				       i, read_vpe_c0_epc(),
+				       (void *) read_vpe_c0_epc());
+				printk("   VPE%d.Cause : %08lx\n",
+				       i, read_vpe_c0_cause());
+				printk("   VPE%d.Config7 : %08lx\n",
+				       i, read_vpe_c0_config7());
+				break; /* Next VPE */
+			}
+		}
+	}
+	printk("-- per-TC State --\n");
+	for (tc = 0; tc < ntc; tc++) {
+		settc(tc);
+		if (read_tc_c0_tcbind() == read_c0_tcbind()) {
+			/* Are we dumping ourself?  */
+			haltval = 0; /* Then we're not halted, and mustn't be */
+			tcstatval = flags; /* And pre-dump TCStatus is flags */
+			printk("  TC %d (current TC with VPE EPC above)\n", tc);
+		} else {
+			haltval = read_tc_c0_tchalt();
+			write_tc_c0_tchalt(1);
+			tcstatval = read_tc_c0_tcstatus();
+			printk("  TC %d\n", tc);
+		}
+		printk("   TCStatus : %08lx\n", tcstatval);
+		printk("   TCBind : %08lx\n", read_tc_c0_tcbind());
+		printk("   TCRestart : %08lx %pS\n",
+		       read_tc_c0_tcrestart(), (void *) read_tc_c0_tcrestart());
+		printk("   TCHalt : %08lx\n", haltval);
+		printk("   TCContext : %08lx\n", read_tc_c0_tccontext());
+		if (!haltval)
+			write_tc_c0_tchalt(0);
+	}
+	printk("===========================\n");
+	evpe(vpflags);
+	local_irq_restore(flags);
+}
+
+static int mt_opt_norps;
+static int mt_opt_rpsctl = -1;
+static int mt_opt_nblsu = -1;
+static int mt_opt_forceconfig7;
+static int mt_opt_config7 = -1;
+
+static int __init rps_disable(char *s)
+{
+	mt_opt_norps = 1;
+	return 1;
+}
+__setup("norps", rps_disable);
+
+static int __init rpsctl_set(char *str)
+{
+	get_option(&str, &mt_opt_rpsctl);
+	return 1;
+}
+__setup("rpsctl=", rpsctl_set);
+
+static int __init nblsu_set(char *str)
+{
+	get_option(&str, &mt_opt_nblsu);
+	return 1;
+}
+__setup("nblsu=", nblsu_set);
+
+static int __init config7_set(char *str)
+{
+	get_option(&str, &mt_opt_config7);
+	mt_opt_forceconfig7 = 1;
+	return 1;
+}
+__setup("config7=", config7_set);
+
+/* Experimental cache flush control parameters that should go away some day */
+int mt_protiflush;
+int mt_protdflush;
+int mt_n_iflushes = 1;
+int mt_n_dflushes = 1;
+
+static int __init set_protiflush(char *s)
+{
+	mt_protiflush = 1;
+	return 1;
+}
+__setup("protiflush", set_protiflush);
+
+static int __init set_protdflush(char *s)
+{
+	mt_protdflush = 1;
+	return 1;
+}
+__setup("protdflush", set_protdflush);
+
+static int __init niflush(char *s)
+{
+	get_option(&s, &mt_n_iflushes);
+	return 1;
+}
+__setup("niflush=", niflush);
+
+static int __init ndflush(char *s)
+{
+	get_option(&s, &mt_n_dflushes);
+	return 1;
+}
+__setup("ndflush=", ndflush);
+
+static unsigned int itc_base;
+
+static int __init set_itc_base(char *str)
+{
+	get_option(&str, &itc_base);
+	return 1;
+}
+
+__setup("itcbase=", set_itc_base);
+
+void mips_mt_set_cpuoptions(void)
+{
+	unsigned int oconfig7 = read_c0_config7();
+	unsigned int nconfig7 = oconfig7;
+
+	if (mt_opt_norps) {
+		printk("\"norps\" option deprecated: use \"rpsctl=\"\n");
+	}
+	if (mt_opt_rpsctl >= 0) {
+		printk("34K return prediction stack override set to %d.\n",
+			mt_opt_rpsctl);
+		if (mt_opt_rpsctl)
+			nconfig7 |= (1 << 2);
+		else
+			nconfig7 &= ~(1 << 2);
+	}
+	if (mt_opt_nblsu >= 0) {
+		printk("34K ALU/LSU sync override set to %d.\n", mt_opt_nblsu);
+		if (mt_opt_nblsu)
+			nconfig7 |= (1 << 5);
+		else
+			nconfig7 &= ~(1 << 5);
+	}
+	if (mt_opt_forceconfig7) {
+		printk("CP0.Config7 forced to 0x%08x.\n", mt_opt_config7);
+		nconfig7 = mt_opt_config7;
+	}
+	if (oconfig7 != nconfig7) {
+		__asm__ __volatile("sync");
+		write_c0_config7(nconfig7);
+		ehb();
+		printk("Config7: 0x%08x\n", read_c0_config7());
+	}
+
+	/* Report Cache management debug options */
+	if (mt_protiflush)
+		printk("I-cache flushes single-threaded\n");
+	if (mt_protdflush)
+		printk("D-cache flushes single-threaded\n");
+	if (mt_n_iflushes != 1)
+		printk("I-Cache Flushes Repeated %d times\n", mt_n_iflushes);
+	if (mt_n_dflushes != 1)
+		printk("D-Cache Flushes Repeated %d times\n", mt_n_dflushes);
+
+	if (itc_base != 0) {
+		/*
+		 * Configure ITC mapping.  This code is very
+		 * specific to the 34K core family, which uses
+		 * a special mode bit ("ITC") in the ErrCtl
+		 * register to enable access to ITC control
+		 * registers via cache "tag" operations.
+		 */
+		unsigned long ectlval;
+		unsigned long itcblkgrn;
+
+		/* ErrCtl register is known as "ecc" to Linux */
+		ectlval = read_c0_ecc();
+		write_c0_ecc(ectlval | (0x1 << 26));
+		ehb();
+#define INDEX_0 (0x80000000)
+#define INDEX_8 (0x80000008)
+		/* Read "cache tag" for Dcache pseudo-index 8 */
+		cache_op(Index_Load_Tag_D, INDEX_8);
+		ehb();
+		itcblkgrn = read_c0_dtaglo();
+		itcblkgrn &= 0xfffe0000;
+		/* Set for 128 byte pitch of ITC cells */
+		itcblkgrn |= 0x00000c00;
+		/* Stage in Tag register */
+		write_c0_dtaglo(itcblkgrn);
+		ehb();
+		/* Write out to ITU with CACHE op */
+		cache_op(Index_Store_Tag_D, INDEX_8);
+		/* Now set base address, and turn ITC on with 0x1 bit */
+		write_c0_dtaglo((itc_base & 0xfffffc00) | 0x1 );
+		ehb();
+		/* Write out to ITU with CACHE op */
+		cache_op(Index_Store_Tag_D, INDEX_0);
+		write_c0_ecc(ectlval);
+		ehb();
+		printk("Mapped %ld ITC cells starting at 0x%08x\n",
+			((itcblkgrn & 0x7fe00000) >> 20), itc_base);
+	}
+}
+
+/*
+ * Function to protect cache flushes from concurrent execution
+ * depends on MP software model chosen.
+ */
+
+void mt_cflush_lockdown(void)
+{
+	/* FILL IN VSMP and AP/SP VERSIONS HERE */
+}
+
+void mt_cflush_release(void)
+{
+	/* FILL IN VSMP and AP/SP VERSIONS HERE */
+}
+
+struct class *mt_class;
+
+static int __init mt_init(void)
+{
+	struct class *mtc;
+
+	mtc = class_create(THIS_MODULE, "mt");
+	if (IS_ERR(mtc))
+		return PTR_ERR(mtc);
+
+	mt_class = mtc;
+
+	return 0;
+}
+
+subsys_initcall(mt_init);