Merge branch 'x86/cpufeature' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into kvm/next

Topic branch for AVX512_4VNNIW and AVX512_4FMAPS support in KVM.

8 files changed, 186 insertions, 232 deletions

diff --git a/arch/arc/kernel/devtree.c b/arch/arc/kernel/devtree.c
index f1e07c2..3b67f53 100644
--- a/arch/arc/kernel/devtree.c
+++ b/arch/arc/kernel/devtree.c
@@ -31,6 +31,8 @@ static void __init arc_set_early_base_baud(unsigned long dt_root)
 		arc_base_baud = 166666666;	/* Fixed 166.6MHz clk (TB10x) */
 	else if (of_flat_dt_is_compatible(dt_root, "snps,arc-sdp"))
 		arc_base_baud = 33333333;	/* Fixed 33MHz clk (AXS10x) */
+	else if (of_flat_dt_is_compatible(dt_root, "ezchip,arc-nps"))
+		arc_base_baud = 800000000;      /* Fixed 800MHz clk (NPS) */
 	else
 		arc_base_baud = 50000000;	/* Fixed default 50MHz */
 }
diff --git a/arch/arc/kernel/mcip.c b/arch/arc/kernel/mcip.c
index 72f9179..f39142a 100644
--- a/arch/arc/kernel/mcip.c
+++ b/arch/arc/kernel/mcip.c
@@ -15,11 +15,12 @@
 #include <asm/mcip.h>
 #include <asm/setup.h>
 
-static char smp_cpuinfo_buf[128];
-static int idu_detected;
-
 static DEFINE_RAW_SPINLOCK(mcip_lock);
 
+#ifdef CONFIG_SMP
+
+static char smp_cpuinfo_buf[128];
+
 static void mcip_setup_per_cpu(int cpu)
 {
 	smp_ipi_irq_setup(cpu, IPI_IRQ);
@@ -86,21 +87,7 @@ static void mcip_ipi_clear(int irq)
 
 static void mcip_probe_n_setup(void)
 {
-	struct mcip_bcr {
-#ifdef CONFIG_CPU_BIG_ENDIAN
-		unsigned int pad3:8,
-			     idu:1, llm:1, num_cores:6,
-			     iocoh:1,  gfrc:1, dbg:1, pad2:1,
-			     msg:1, sem:1, ipi:1, pad:1,
-			     ver:8;
-#else
-		unsigned int ver:8,
-			     pad:1, ipi:1, sem:1, msg:1,
-			     pad2:1, dbg:1, gfrc:1, iocoh:1,
-			     num_cores:6, llm:1, idu:1,
-			     pad3:8;
-#endif
-	} mp;
+	struct mcip_bcr mp;
 
 	READ_BCR(ARC_REG_MCIP_BCR, mp);
 
@@ -114,7 +101,6 @@ static void mcip_probe_n_setup(void)
 		IS_AVAIL1(mp.gfrc, "GFRC"));
 
 	cpuinfo_arc700[0].extn.gfrc = mp.gfrc;
-	idu_detected = mp.idu;
 
 	if (mp.dbg) {
 		__mcip_cmd_data(CMD_DEBUG_SET_SELECT, 0, 0xf);
@@ -130,6 +116,8 @@ struct plat_smp_ops plat_smp_ops = {
 	.ipi_clear	= mcip_ipi_clear,
 };
 
+#endif
+
 /***************************************************************************
  * ARCv2 Interrupt Distribution Unit (IDU)
  *
@@ -193,6 +181,8 @@ idu_irq_set_affinity(struct irq_data *data, const struct cpumask *cpumask,
 {
 	unsigned long flags;
 	cpumask_t online;
+	unsigned int destination_bits;
+	unsigned int distribution_mode;
 
 	/* errout if no online cpu per @cpumask */
 	if (!cpumask_and(&online, cpumask, cpu_online_mask))
@@ -200,8 +190,15 @@ idu_irq_set_affinity(struct irq_data *data, const struct cpumask *cpumask,
 
 	raw_spin_lock_irqsave(&mcip_lock, flags);
 
-	idu_set_dest(data->hwirq, cpumask_bits(&online)[0]);
-	idu_set_mode(data->hwirq, IDU_M_TRIG_LEVEL, IDU_M_DISTRI_RR);
+	destination_bits = cpumask_bits(&online)[0];
+	idu_set_dest(data->hwirq, destination_bits);
+
+	if (ffs(destination_bits) == fls(destination_bits))
+		distribution_mode = IDU_M_DISTRI_DEST;
+	else
+		distribution_mode = IDU_M_DISTRI_RR;
+
+	idu_set_mode(data->hwirq, IDU_M_TRIG_LEVEL, distribution_mode);
 
 	raw_spin_unlock_irqrestore(&mcip_lock, flags);
 
@@ -219,16 +216,15 @@ static struct irq_chip idu_irq_chip = {
 
 };
 
-static int idu_first_irq;
+static irq_hw_number_t idu_first_hwirq;
 
 static void idu_cascade_isr(struct irq_desc *desc)
 {
-	struct irq_domain *domain = irq_desc_get_handler_data(desc);
-	unsigned int core_irq = irq_desc_get_irq(desc);
-	unsigned int idu_irq;
+	struct irq_domain *idu_domain = irq_desc_get_handler_data(desc);
+	irq_hw_number_t core_hwirq = irqd_to_hwirq(irq_desc_get_irq_data(desc));
+	irq_hw_number_t idu_hwirq = core_hwirq - idu_first_hwirq;
 
-	idu_irq = core_irq - idu_first_irq;
-	generic_handle_irq(irq_find_mapping(domain, idu_irq));
+	generic_handle_irq(irq_find_mapping(idu_domain, idu_hwirq));
 }
 
 static int idu_irq_map(struct irq_domain *d, unsigned int virq, irq_hw_number_t hwirq)
@@ -294,9 +290,12 @@ idu_of_init(struct device_node *intc, struct device_node *parent)
 	struct irq_domain *domain;
 	/* Read IDU BCR to confirm nr_irqs */
 	int nr_irqs = of_irq_count(intc);
-	int i, irq;
+	int i, virq;
+	struct mcip_bcr mp;
+
+	READ_BCR(ARC_REG_MCIP_BCR, mp);
 
-	if (!idu_detected)
+	if (!mp.idu)
 		panic("IDU not detected, but DeviceTree using it");
 
 	pr_info("MCIP: IDU referenced from Devicetree %d irqs\n", nr_irqs);
@@ -312,11 +311,11 @@ idu_of_init(struct device_node *intc, struct device_node *parent)
 		 * however we need it to get the parent virq and set IDU handler
 		 * as first level isr
 		 */
-		irq = irq_of_parse_and_map(intc, i);
+		virq = irq_of_parse_and_map(intc, i);
 		if (!i)
-			idu_first_irq = irq;
+			idu_first_hwirq = irqd_to_hwirq(irq_get_irq_data(virq));
 
-		irq_set_chained_handler_and_data(irq, idu_cascade_isr, domain);
+		irq_set_chained_handler_and_data(virq, idu_cascade_isr, domain);
 	}
 
 	__mcip_cmd(CMD_IDU_ENABLE, 0);
diff --git a/arch/arc/kernel/module.c b/arch/arc/kernel/module.c
index 9a28497..42e964d 100644
--- a/arch/arc/kernel/module.c
+++ b/arch/arc/kernel/module.c
@@ -30,17 +30,9 @@ int module_frob_arch_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
 			      char *secstr, struct module *mod)
 {
 #ifdef CONFIG_ARC_DW2_UNWIND
-	int i;
-
 	mod->arch.unw_sec_idx = 0;
 	mod->arch.unw_info = NULL;
-
-	for (i = 1; i < hdr->e_shnum; i++) {
-		if (strcmp(secstr+sechdrs[i].sh_name, ".eh_frame") == 0) {
-			mod->arch.unw_sec_idx = i;
-			break;
-		}
-	}
+	mod->arch.secstr = secstr;
 #endif
 	return 0;
 }
@@ -59,29 +51,33 @@ int apply_relocate_add(Elf32_Shdr *sechdrs,
 		       unsigned int relsec,	/* sec index for relo sec */
 		       struct module *module)
 {
-	int i, n;
+	int i, n, relo_type;
 	Elf32_Rela *rel_entry = (void *)sechdrs[relsec].sh_addr;
 	Elf32_Sym *sym_entry, *sym_sec;
-	Elf32_Addr relocation;
-	Elf32_Addr location;
-	Elf32_Addr sec_to_patch;
-	int relo_type;
-
-	sec_to_patch = sechdrs[sechdrs[relsec].sh_info].sh_addr;
+	Elf32_Addr relocation, location, tgt_addr;
+	unsigned int tgtsec;
+
+	/*
+	 * @relsec has relocations e.g. .rela.init.text
+	 * @tgtsec is section to patch e.g. .init.text
+	 */
+	tgtsec = sechdrs[relsec].sh_info;
+	tgt_addr = sechdrs[tgtsec].sh_addr;
 	sym_sec = (Elf32_Sym *) sechdrs[symindex].sh_addr;
 	n = sechdrs[relsec].sh_size / sizeof(*rel_entry);
 
-	pr_debug("\n========== Module Sym reloc ===========================\n");
-	pr_debug("Section to fixup %x\n", sec_to_patch);
+	pr_debug("\nSection to fixup %s @%x\n",
+		 module->arch.secstr + sechdrs[tgtsec].sh_name, tgt_addr);
 	pr_debug("=========================================================\n");
-	pr_debug("rela->r_off | rela->addend | sym->st_value | ADDR | VALUE\n");
+	pr_debug("r_off\tr_add\tst_value ADDRESS  VALUE\n");
 	pr_debug("=========================================================\n");
 
 	/* Loop thru entries in relocation section */
 	for (i = 0; i < n; i++) {
+		const char *s;
 
 		/* This is where to make the change */
-		location = sec_to_patch + rel_entry[i].r_offset;
+		location = tgt_addr + rel_entry[i].r_offset;
 
 		/* This is the symbol it is referring to.  Note that all
 		   undefined symbols have been resolved.  */
@@ -89,10 +85,15 @@ int apply_relocate_add(Elf32_Shdr *sechdrs,
 
 		relocation = sym_entry->st_value + rel_entry[i].r_addend;
 
-		pr_debug("\t%x\t\t%x\t\t%x  %x %x [%s]\n",
-			rel_entry[i].r_offset, rel_entry[i].r_addend,
-			sym_entry->st_value, location, relocation,
-			strtab + sym_entry->st_name);
+		if (sym_entry->st_name == 0 && ELF_ST_TYPE (sym_entry->st_info) == STT_SECTION) {
+			s = module->arch.secstr + sechdrs[sym_entry->st_shndx].sh_name;
+		} else {
+			s = strtab + sym_entry->st_name;
+		}
+
+		pr_debug("   %x\t%x\t%x %x %x [%s]\n",
+			 rel_entry[i].r_offset, rel_entry[i].r_addend,
+			 sym_entry->st_value, location, relocation, s);
 
 		/* This assumes modules are built with -mlong-calls
 		 * so any branches/jumps are absolute 32 bit jmps
@@ -111,6 +112,10 @@ int apply_relocate_add(Elf32_Shdr *sechdrs,
 			goto relo_err;
 
 	}
+
+	if (strcmp(module->arch.secstr+sechdrs[tgtsec].sh_name, ".eh_frame") == 0)
+		module->arch.unw_sec_idx = tgtsec;
+
 	return 0;
 
 relo_err:
diff --git a/arch/arc/kernel/process.c b/arch/arc/kernel/process.c
index be1972b..a41a79a 100644
--- a/arch/arc/kernel/process.c
+++ b/arch/arc/kernel/process.c
@@ -41,6 +41,41 @@ SYSCALL_DEFINE0(arc_gettls)
 	return task_thread_info(current)->thr_ptr;
 }
 
+SYSCALL_DEFINE3(arc_usr_cmpxchg, int *, uaddr, int, expected, int, new)
+{
+	struct pt_regs *regs = current_pt_regs();
+	int uval = -EFAULT;
+
+	/*
+	 * This is only for old cores lacking LLOCK/SCOND, which by defintion
+	 * can't possibly be SMP. Thus doesn't need to be SMP safe.
+	 * And this also helps reduce the overhead for serializing in
+	 * the UP case
+	 */
+	WARN_ON_ONCE(IS_ENABLED(CONFIG_SMP));
+
+	/* Z indicates to userspace if operation succeded */
+	regs->status32 &= ~STATUS_Z_MASK;
+
+	if (!access_ok(VERIFY_WRITE, uaddr, sizeof(int)))
+		return -EFAULT;
+
+	preempt_disable();
+
+	if (__get_user(uval, uaddr))
+		goto done;
+
+	if (uval == expected) {
+		if (!__put_user(new, uaddr))
+			regs->status32 |= STATUS_Z_MASK;
+	}
+
+done:
+	preempt_enable();
+
+	return uval;
+}
+
 void arch_cpu_idle(void)
 {
 	/* sleep, but enable all interrupts before committing */
diff --git a/arch/arc/kernel/setup.c b/arch/arc/kernel/setup.c
index 3df7f9c..0385df7 100644
--- a/arch/arc/kernel/setup.c
+++ b/arch/arc/kernel/setup.c
@@ -40,6 +40,29 @@ struct task_struct *_current_task[NR_CPUS];	/* For stack switching */
 
 struct cpuinfo_arc cpuinfo_arc700[NR_CPUS];
 
+static const struct id_to_str arc_cpu_rel[] = {
+#ifdef CONFIG_ISA_ARCOMPACT
+	{ 0x34, "R4.10"},
+	{ 0x35, "R4.11"},
+#else
+	{ 0x51, "R2.0" },
+	{ 0x52, "R2.1" },
+	{ 0x53, "R3.0" },
+#endif
+	{ 0x00, NULL   }
+};
+
+static const struct id_to_str arc_cpu_nm[] = {
+#ifdef CONFIG_ISA_ARCOMPACT
+	{ 0x20, "ARC 600"   },
+	{ 0x30, "ARC 770"   },  /* 750 identified seperately */
+#else
+	{ 0x40, "ARC EM"  },
+	{ 0x50, "ARC HS38"  },
+#endif
+	{ 0x00, "Unknown"   }
+};
+
 static void read_decode_ccm_bcr(struct cpuinfo_arc *cpu)
 {
 	if (is_isa_arcompact()) {
@@ -92,11 +115,26 @@ static void read_arc_build_cfg_regs(void)
 	struct bcr_timer timer;
 	struct bcr_generic bcr;
 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
+	const struct id_to_str *tbl;
+
 	FIX_PTR(cpu);
 
 	READ_BCR(AUX_IDENTITY, cpu->core);
 	READ_BCR(ARC_REG_ISA_CFG_BCR, cpu->isa);
 
+	for (tbl = &arc_cpu_rel[0]; tbl->id != 0; tbl++) {
+		if (cpu->core.family == tbl->id) {
+			cpu->details = tbl->str;
+			break;
+		}
+	}
+
+	for (tbl = &arc_cpu_nm[0]; tbl->id != 0; tbl++) {
+		if ((cpu->core.family & 0xF0) == tbl->id)
+			break;
+	}
+	cpu->name = tbl->str;
+
 	READ_BCR(ARC_REG_TIMERS_BCR, timer);
 	cpu->extn.timer0 = timer.t0;
 	cpu->extn.timer1 = timer.t1;
@@ -111,6 +149,9 @@ static void read_arc_build_cfg_regs(void)
 	cpu->extn.swap = read_aux_reg(ARC_REG_SWAP_BCR) ? 1 : 0;        /* 1,3 */
 	cpu->extn.crc = read_aux_reg(ARC_REG_CRC_BCR) ? 1 : 0;
 	cpu->extn.minmax = read_aux_reg(ARC_REG_MIXMAX_BCR) > 1 ? 1 : 0; /* 2 */
+	cpu->extn.swape = (cpu->core.family >= 0x34) ? 1 :
+				IS_ENABLED(CONFIG_ARC_HAS_SWAPE);
+
 	READ_BCR(ARC_REG_XY_MEM_BCR, cpu->extn_xymem);
 
 	/* Read CCM BCRs for boot reporting even if not enabled in Kconfig */
@@ -160,64 +201,38 @@ static void read_arc_build_cfg_regs(void)
 	cpu->extn.rtt = bcr.ver ? 1 : 0;
 
 	cpu->extn.debug = cpu->extn.ap | cpu->extn.smart | cpu->extn.rtt;
-}
 
-static const struct cpuinfo_data arc_cpu_tbl[] = {
-#ifdef CONFIG_ISA_ARCOMPACT
-	{ {0x20, "ARC 600"      }, 0x2F},
-	{ {0x30, "ARC 700"      }, 0x33},
-	{ {0x34, "ARC 700 R4.10"}, 0x34},
-	{ {0x35, "ARC 700 R4.11"}, 0x35},
-#else
-	{ {0x50, "ARC HS38 R2.0"}, 0x51},
-	{ {0x52, "ARC HS38 R2.1"}, 0x52},
-	{ {0x53, "ARC HS38 R3.0"}, 0x53},
-#endif
-	{ {0x00, NULL		} }
-};
+	/* some hacks for lack of feature BCR info in old ARC700 cores */
+	if (is_isa_arcompact()) {
+		if (!cpu->isa.ver)	/* ISA BCR absent, use Kconfig info */
+			cpu->isa.atomic = IS_ENABLED(CONFIG_ARC_HAS_LLSC);
+		else
+			cpu->isa.atomic = cpu->isa.atomic1;
 
+		cpu->isa.be = IS_ENABLED(CONFIG_CPU_BIG_ENDIAN);
+
+		 /* there's no direct way to distinguish 750 vs. 770 */
+		if (unlikely(cpu->core.family < 0x34 || cpu->mmu.ver < 3))
+			cpu->name = "ARC750";
+	}
+}
 
 static char *arc_cpu_mumbojumbo(int cpu_id, char *buf, int len)
 {
 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id];
 	struct bcr_identity *core = &cpu->core;
-	const struct cpuinfo_data *tbl;
-	char *isa_nm;
-	int i, be, atomic;
-	int n = 0;
+	int i, n = 0;
 
 	FIX_PTR(cpu);
 
-	if (is_isa_arcompact()) {
-		isa_nm = "ARCompact";
-		be = IS_ENABLED(CONFIG_CPU_BIG_ENDIAN);
-
-		atomic = cpu->isa.atomic1;
-		if (!cpu->isa.ver)	/* ISA BCR absent, use Kconfig info */
-			atomic = IS_ENABLED(CONFIG_ARC_HAS_LLSC);
-	} else {
-		isa_nm = "ARCv2";
-		be = cpu->isa.be;
-		atomic = cpu->isa.atomic;
-	}
-
 	n += scnprintf(buf + n, len - n,
 		       "\nIDENTITY\t: ARCVER [%#02x] ARCNUM [%#02x] CHIPID [%#4x]\n",
 		       core->family, core->cpu_id, core->chip_id);
 
-	for (tbl = &arc_cpu_tbl[0]; tbl->info.id != 0; tbl++) {
-		if ((core->family >= tbl->info.id) &&
-		    (core->family <= tbl->up_range)) {
-			n += scnprintf(buf + n, len - n,
-				       "processor [%d]\t: %s (%s ISA) %s\n",
-				       cpu_id, tbl->info.str, isa_nm,
-				       IS_AVAIL1(be, "[Big-Endian]"));
-			break;
-		}
-	}
-
-	if (tbl->info.id == 0)
-		n += scnprintf(buf + n, len - n, "UNKNOWN ARC Processor\n");
+	n += scnprintf(buf + n, len - n, "processor [%d]\t: %s %s (%s ISA) %s\n",
+		       cpu_id, cpu->name, cpu->details,
+		       is_isa_arcompact() ? "ARCompact" : "ARCv2",
+		       IS_AVAIL1(cpu->isa.be, "[Big-Endian]"));
 
 	n += scnprintf(buf + n, len - n, "Timers\t\t: %s%s%s%s\nISA Extn\t: ",
 		       IS_AVAIL1(cpu->extn.timer0, "Timer0 "),
@@ -226,7 +241,7 @@ static char *arc_cpu_mumbojumbo(int cpu_id, char *buf, int len)
 				 CONFIG_ARC_HAS_RTC));
 
 	n += i = scnprintf(buf + n, len - n, "%s%s%s%s%s",
-			   IS_AVAIL2(atomic, "atomic ", CONFIG_ARC_HAS_LLSC),
+			   IS_AVAIL2(cpu->isa.atomic, "atomic ", CONFIG_ARC_HAS_LLSC),
 			   IS_AVAIL2(cpu->isa.ldd, "ll64 ", CONFIG_ARC_HAS_LL64),
 			   IS_AVAIL1(cpu->isa.unalign, "unalign (not used)"));
 
@@ -253,7 +268,7 @@ static char *arc_cpu_mumbojumbo(int cpu_id, char *buf, int len)
 		       IS_AVAIL1(cpu->extn.swap, "swap "),
 		       IS_AVAIL1(cpu->extn.minmax, "minmax "),
 		       IS_AVAIL1(cpu->extn.crc, "crc "),
-		       IS_AVAIL2(1, "swape", CONFIG_ARC_HAS_SWAPE));
+		       IS_AVAIL2(cpu->extn.swape, "swape", CONFIG_ARC_HAS_SWAPE));
 
 	if (cpu->bpu.ver)
 		n += scnprintf(buf + n, len - n,
@@ -272,9 +287,7 @@ static char *arc_extn_mumbojumbo(int cpu_id, char *buf, int len)
 
 	FIX_PTR(cpu);
 
-	n += scnprintf(buf + n, len - n,
-		       "Vector Table\t: %#x\nPeripherals\t: %#lx:%#lx\n",
-		       cpu->vec_base, perip_base, perip_end);
+	n += scnprintf(buf + n, len - n, "Vector Table\t: %#x\n", cpu->vec_base);
 
 	if (cpu->extn.fpu_sp || cpu->extn.fpu_dp)
 		n += scnprintf(buf + n, len - n, "FPU\t\t: %s%s\n",
@@ -507,7 +520,7 @@ static void *c_start(struct seq_file *m, loff_t *pos)
 	 * way to pass it w/o having to kmalloc/free a 2 byte string.
 	 * Encode cpu-id as 0xFFcccc, which is decoded by show routine.
 	 */
-	return *pos < num_possible_cpus() ? cpu_to_ptr(*pos) : NULL;
+	return *pos < nr_cpu_ids ? cpu_to_ptr(*pos) : NULL;
 }
 
 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
diff --git a/arch/arc/kernel/smp.c b/arch/arc/kernel/smp.c
index f183cc6..88674d9 100644
--- a/arch/arc/kernel/smp.c
+++ b/arch/arc/kernel/smp.c
@@ -22,6 +22,7 @@
 #include <linux/atomic.h>
 #include <linux/cpumask.h>
 #include <linux/reboot.h>
+#include <linux/irqdomain.h>
 #include <asm/processor.h>
 #include <asm/setup.h>
 #include <asm/mach_desc.h>
@@ -67,11 +68,13 @@ void __init smp_prepare_cpus(unsigned int max_cpus)
 	int i;
 
 	/*
-	 * Initialise the present map, which describes the set of CPUs
-	 * actually populated at the present time.
+	 * if platform didn't set the present map already, do it now
+	 * boot cpu is set to present already by init/main.c
 	 */
-	for (i = 0; i < max_cpus; i++)
-		set_cpu_present(i, true);
+	if (num_present_cpus() <= 1) {
+		for (i = 0; i < max_cpus; i++)
+			set_cpu_present(i, true);
+	}
 }
 
 void __init smp_cpus_done(unsigned int max_cpus)
@@ -351,20 +354,24 @@ irqreturn_t do_IPI(int irq, void *dev_id)
  */
 static DEFINE_PER_CPU(int, ipi_dev);
 
-int smp_ipi_irq_setup(int cpu, int irq)
+int smp_ipi_irq_setup(int cpu, irq_hw_number_t hwirq)
 {
 	int *dev = per_cpu_ptr(&ipi_dev, cpu);
+	unsigned int virq = irq_find_mapping(NULL, hwirq);
+
+	if (!virq)
+		panic("Cannot find virq for root domain and hwirq=%lu", hwirq);
 
 	/* Boot cpu calls request, all call enable */
 	if (!cpu) {
 		int rc;
 
-		rc = request_percpu_irq(irq, do_IPI, "IPI Interrupt", dev);
+		rc = request_percpu_irq(virq, do_IPI, "IPI Interrupt", dev);
 		if (rc)
-			panic("Percpu IRQ request failed for %d\n", irq);
+			panic("Percpu IRQ request failed for %u\n", virq);
 	}
 
-	enable_percpu_irq(irq, 0);
+	enable_percpu_irq(virq, 0);
 
 	return 0;
 }
diff --git a/arch/arc/kernel/time.c b/arch/arc/kernel/time.c
index f927b8d..c10390d 100644
--- a/arch/arc/kernel/time.c
+++ b/arch/arc/kernel/time.c
@@ -152,14 +152,17 @@ static cycle_t arc_read_rtc(struct clocksource *cs)
 		cycle_t  full;
 	} stamp;
 
-
-	__asm__ __volatile(
-	"1:						\n"
-	"	lr		%0, [AUX_RTC_LOW]	\n"
-	"	lr		%1, [AUX_RTC_HIGH]	\n"
-	"	lr		%2, [AUX_RTC_CTRL]	\n"
-	"	bbit0.nt	%2, 31, 1b		\n"
-	: "=r" (stamp.low), "=r" (stamp.high), "=r" (status));
+	/*
+	 * hardware has an internal state machine which tracks readout of
+	 * low/high and updates the CTRL.status if
+	 *  - interrupt/exception taken between the two reads
+	 *  - high increments after low has been read
+	 */
+	do {
+		stamp.low = read_aux_reg(AUX_RTC_LOW);
+		stamp.high = read_aux_reg(AUX_RTC_HIGH);
+		status = read_aux_reg(AUX_RTC_CTRL);
+	} while (!(status & _BITUL(31)));
 
 	return stamp.full;
 }
diff --git a/arch/arc/kernel/troubleshoot.c b/arch/arc/kernel/troubleshoot.c
index 934150e..82f9bc8 100644
--- a/arch/arc/kernel/troubleshoot.c
+++ b/arch/arc/kernel/troubleshoot.c
@@ -237,113 +237,3 @@ void show_kernel_fault_diag(const char *str, struct pt_regs *regs,
 	if (!user_mode(regs))
 		show_stacktrace(current, regs);
 }
-
-#ifdef CONFIG_DEBUG_FS
-
-#include <linux/module.h>
-#include <linux/fs.h>
-#include <linux/mount.h>
-#include <linux/pagemap.h>
-#include <linux/init.h>
-#include <linux/namei.h>
-#include <linux/debugfs.h>
-
-static struct dentry *test_dentry;
-static struct dentry *test_dir;
-static struct dentry *test_u32_dentry;
-
-static u32 clr_on_read = 1;
-
-#ifdef CONFIG_ARC_DBG_TLB_MISS_COUNT
-u32 numitlb, numdtlb, num_pte_not_present;
-
-static int fill_display_data(char *kbuf)
-{
-	size_t num = 0;
-	num += sprintf(kbuf + num, "I-TLB Miss %x\n", numitlb);
-	num += sprintf(kbuf + num, "D-TLB Miss %x\n", numdtlb);
-	num += sprintf(kbuf + num, "PTE not present %x\n", num_pte_not_present);
-
-	if (clr_on_read)
-		numitlb = numdtlb = num_pte_not_present = 0;
-
-	return num;
-}
-
-static int tlb_stats_open(struct inode *inode, struct file *file)
-{
-	file->private_data = (void *)__get_free_page(GFP_KERNEL);
-	return 0;
-}
-
-/* called on user read(): display the counters */
-static ssize_t tlb_stats_output(struct file *file,	/* file descriptor */
-				char __user *user_buf,	/* user buffer */
-				size_t len,		/* length of buffer */
-				loff_t *offset)		/* offset in the file */
-{
-	size_t num;
-	char *kbuf = (char *)file->private_data;
-
-	/* All of the data can he shoved in one iteration */
-	if (*offset != 0)
-		return 0;
-
-	num = fill_display_data(kbuf);
-
-	/* simple_read_from_buffer() is helper for copy to user space
-	   It copies up to @2 (num) bytes from kernel buffer @4 (kbuf) at offset
-	   @3 (offset) into the user space address starting at @1 (user_buf).
-	   @5 (len) is max size of user buffer
-	 */
-	return simple_read_from_buffer(user_buf, num, offset, kbuf, len);
-}
-
-/* called on user write : clears the counters */
-static ssize_t tlb_stats_clear(struct file *file, const char __user *user_buf,
-			       size_t length, loff_t *offset)
-{
-	numitlb = numdtlb = num_pte_not_present = 0;
-	return length;
-}
-
-static int tlb_stats_close(struct inode *inode, struct file *file)
-{
-	free_page((unsigned long)(file->private_data));
-	return 0;
-}
-
-static const struct file_operations tlb_stats_file_ops = {
-	.read = tlb_stats_output,
-	.write = tlb_stats_clear,
-	.open = tlb_stats_open,
-	.release = tlb_stats_close
-};
-#endif
-
-static int __init arc_debugfs_init(void)
-{
-	test_dir = debugfs_create_dir("arc", NULL);
-
-#ifdef CONFIG_ARC_DBG_TLB_MISS_COUNT
-	test_dentry = debugfs_create_file("tlb_stats", 0444, test_dir, NULL,
-					  &tlb_stats_file_ops);
-#endif
-
-	test_u32_dentry =
-	    debugfs_create_u32("clr_on_read", 0444, test_dir, &clr_on_read);
-
-	return 0;
-}
-
-module_init(arc_debugfs_init);
-
-static void __exit arc_debugfs_exit(void)
-{
-	debugfs_remove(test_u32_dentry);
-	debugfs_remove(test_dentry);
-	debugfs_remove(test_dir);
-}
-module_exit(arc_debugfs_exit);
-
-#endif