Merge Linus' tree to be be to apply submitted patches to newer code than

current trivial.git base

10 files changed, 219 insertions, 249 deletions

diff --git a/arch/arc/kernel/Makefile b/arch/arc/kernel/Makefile
index 8004b4fa646..113f2033da9 100644
--- a/arch/arc/kernel/Makefile
+++ b/arch/arc/kernel/Makefile
@@ -16,7 +16,7 @@ obj-$(CONFIG_MODULES)			+= arcksyms.o module.o
 obj-$(CONFIG_SMP) 			+= smp.o
 obj-$(CONFIG_ARC_DW2_UNWIND)		+= unwind.o
 obj-$(CONFIG_KPROBES)      		+= kprobes.o
-obj-$(CONFIG_ARC_MISALIGN_ACCESS) 	+= unaligned.o
+obj-$(CONFIG_ARC_EMUL_UNALIGNED) 	+= unaligned.o
 obj-$(CONFIG_KGDB)			+= kgdb.o
 obj-$(CONFIG_ARC_METAWARE_HLINK)	+= arc_hostlink.o
 obj-$(CONFIG_PERF_EVENTS)		+= perf_event.o
diff --git a/arch/arc/kernel/disasm.c b/arch/arc/kernel/disasm.c
index b8a549c4f54..3b7cd4864ba 100644
--- a/arch/arc/kernel/disasm.c
+++ b/arch/arc/kernel/disasm.c
@@ -15,7 +15,7 @@
 #include <linux/uaccess.h>
 #include <asm/disasm.h>
 
-#if defined(CONFIG_KGDB) || defined(CONFIG_ARC_MISALIGN_ACCESS) || \
+#if defined(CONFIG_KGDB) || defined(CONFIG_ARC_EMUL_UNALIGNED) || \
 	defined(CONFIG_KPROBES)
 
 /* disasm_instr: Analyses instruction at addr, stores
@@ -535,4 +535,4 @@ int __kprobes disasm_next_pc(unsigned long pc, struct pt_regs *regs,
 	return instr.is_branch;
 }
 
-#endif /* CONFIG_KGDB || CONFIG_ARC_MISALIGN_ACCESS || CONFIG_KPROBES */
+#endif /* CONFIG_KGDB || CONFIG_ARC_EMUL_UNALIGNED || CONFIG_KPROBES */
diff --git a/arch/arc/kernel/head.S b/arch/arc/kernel/head.S
index 4d2481bd8b9..b0e8666fdcc 100644
--- a/arch/arc/kernel/head.S
+++ b/arch/arc/kernel/head.S
@@ -91,16 +91,6 @@ stext:
 	st	r0, [@uboot_tag]
 	st	r2, [@uboot_arg]
 
-	; Identify if running on ISS vs Silicon
-	; 	IDENTITY Reg [ 3  2  1  0 ]
-	;	(chip-id)      ^^^^^		==> 0xffff for ISS
-	lr	r0, [identity]
-	lsr	r3, r0, 16
-	cmp	r3, 0xffff
-	mov.z	r4, 0
-	mov.nz	r4, 1
-	st	r4, [@running_on_hw]
-
 	; setup "current" tsk and optionally cache it in dedicated r25
 	mov	r9, @init_task
 	SET_CURR_TASK_ON_CPU  r9, r0	; r9 = tsk, r0 = scratch
diff --git a/arch/arc/kernel/irq.c b/arch/arc/kernel/irq.c
index 7d653c0d077..620ec2fe32a 100644
--- a/arch/arc/kernel/irq.c
+++ b/arch/arc/kernel/irq.c
@@ -19,21 +19,16 @@
 
 /*
  * Early Hardware specific Interrupt setup
+ * -Platform independent, needed for each CPU (not foldable into init_IRQ)
  * -Called very early (start_kernel -> setup_arch -> setup_processor)
- * -Platform Independent (must for any ARC700)
- * -Needed for each CPU (hence not foldable into init_IRQ)
  *
  * what it does ?
- * -Disable all IRQs (on CPU side)
  * -Optionally, setup the High priority Interrupts as Level 2 IRQs
  */
 void arc_init_IRQ(void)
 {
 	int level_mask = 0;
 
-	/* Disable all IRQs: enable them as devices request */
-	write_aux_reg(AUX_IENABLE, 0);
-
        /* setup any high priority Interrupts (Level2 in ARCompact jargon) */
 	level_mask |= IS_ENABLED(CONFIG_ARC_IRQ3_LV2) << 3;
 	level_mask |= IS_ENABLED(CONFIG_ARC_IRQ5_LV2) << 5;
@@ -60,20 +55,28 @@ void arc_init_IRQ(void)
  * below, per IRQ.
  */
 
-static void arc_mask_irq(struct irq_data *data)
+static void arc_irq_mask(struct irq_data *data)
 {
-	arch_mask_irq(data->irq);
+	unsigned int ienb;
+
+	ienb = read_aux_reg(AUX_IENABLE);
+	ienb &= ~(1 << data->irq);
+	write_aux_reg(AUX_IENABLE, ienb);
 }
 
-static void arc_unmask_irq(struct irq_data *data)
+static void arc_irq_unmask(struct irq_data *data)
 {
-	arch_unmask_irq(data->irq);
+	unsigned int ienb;
+
+	ienb = read_aux_reg(AUX_IENABLE);
+	ienb |= (1 << data->irq);
+	write_aux_reg(AUX_IENABLE, ienb);
 }
 
 static struct irq_chip onchip_intc = {
 	.name           = "ARC In-core Intc",
-	.irq_mask	= arc_mask_irq,
-	.irq_unmask	= arc_unmask_irq,
+	.irq_mask	= arc_irq_mask,
+	.irq_unmask	= arc_irq_unmask,
 };
 
 static int arc_intc_domain_map(struct irq_domain *d, unsigned int irq,
@@ -150,6 +153,32 @@ void arch_do_IRQ(unsigned int irq, struct pt_regs *regs)
 	set_irq_regs(old_regs);
 }
 
+void arc_request_percpu_irq(int irq, int cpu,
+                            irqreturn_t (*isr)(int irq, void *dev),
+                            const char *irq_nm,
+                            void *percpu_dev)
+{
+	/* Boot cpu calls request, all call enable */
+	if (!cpu) {
+		int rc;
+
+		/*
+		 * These 2 calls are essential to making percpu IRQ APIs work
+		 * Ideally these details could be hidden in irq chip map function
+		 * but the issue is IPIs IRQs being static (non-DT) and platform
+		 * specific, so we can't identify them there.
+		 */
+		irq_set_percpu_devid(irq);
+		irq_modify_status(irq, IRQ_NOAUTOEN, 0);  /* @irq, @clr, @set */
+
+		rc = request_percpu_irq(irq, isr, irq_nm, percpu_dev);
+		if (rc)
+			panic("Percpu IRQ request failed for %d\n", irq);
+	}
+
+	enable_percpu_irq(irq, 0);
+}
+
 /*
  * arch_local_irq_enable - Enable interrupts.
  *
diff --git a/arch/arc/kernel/kgdb.c b/arch/arc/kernel/kgdb.c
index a2ff5c5d145..ecf6a786937 100644
--- a/arch/arc/kernel/kgdb.c
+++ b/arch/arc/kernel/kgdb.c
@@ -158,11 +158,6 @@ int kgdb_arch_handle_exception(int e_vector, int signo, int err_code,
 	return -1;
 }
 
-unsigned long kgdb_arch_pc(int exception, struct pt_regs *regs)
-{
-	return instruction_pointer(regs);
-}
-
 int kgdb_arch_init(void)
 {
 	single_step_data.armed = 0;
diff --git a/arch/arc/kernel/perf_event.c b/arch/arc/kernel/perf_event.c
index b9a5685a990..ae1c485cbc6 100644
--- a/arch/arc/kernel/perf_event.c
+++ b/arch/arc/kernel/perf_event.c
@@ -244,25 +244,23 @@ static int arc_pmu_device_probe(struct platform_device *pdev)
 		pr_err("This core does not have performance counters!\n");
 		return -ENODEV;
 	}
+	BUG_ON(pct_bcr.c > ARC_PMU_MAX_HWEVENTS);
 
-	arc_pmu = devm_kzalloc(&pdev->dev, sizeof(struct arc_pmu),
-			       GFP_KERNEL);
+	READ_BCR(ARC_REG_CC_BUILD, cc_bcr);
+	if (!cc_bcr.v) {
+		pr_err("Performance counters exist, but no countable conditions?\n");
+		return -ENODEV;
+	}
+
+	arc_pmu = devm_kzalloc(&pdev->dev, sizeof(struct arc_pmu), GFP_KERNEL);
 	if (!arc_pmu)
 		return -ENOMEM;
 
 	arc_pmu->n_counters = pct_bcr.c;
-	BUG_ON(arc_pmu->n_counters > ARC_PMU_MAX_HWEVENTS);
-
 	arc_pmu->counter_size = 32 + (pct_bcr.s << 4);
-	pr_info("ARC PMU found with %d counters of size %d bits\n",
-		arc_pmu->n_counters, arc_pmu->counter_size);
-
-	READ_BCR(ARC_REG_CC_BUILD, cc_bcr);
-
-	if (!cc_bcr.v)
-		pr_err("Strange! Performance counters exist, but no countable conditions?\n");
 
-	pr_info("ARC PMU has %d countable conditions\n", cc_bcr.c);
+	pr_info("ARC perf\t: %d counters (%d bits), %d countable conditions\n",
+		arc_pmu->n_counters, arc_pmu->counter_size, cc_bcr.c);
 
 	cc_name.str[8] = 0;
 	for (i = 0; i < PERF_COUNT_HW_MAX; i++)
diff --git a/arch/arc/kernel/setup.c b/arch/arc/kernel/setup.c
index 119dddb752b..252bf603db9 100644
--- a/arch/arc/kernel/setup.c
+++ b/arch/arc/kernel/setup.c
@@ -13,7 +13,9 @@
 #include <linux/console.h>
 #include <linux/module.h>
 #include <linux/cpu.h>
+#include <linux/clk-provider.h>
 #include <linux/of_fdt.h>
+#include <linux/of_platform.h>
 #include <linux/cache.h>
 #include <asm/sections.h>
 #include <asm/arcregs.h>
@@ -24,11 +26,10 @@
 #include <asm/unwind.h>
 #include <asm/clk.h>
 #include <asm/mach_desc.h>
+#include <asm/smp.h>
 
 #define FIX_PTR(x)  __asm__ __volatile__(";" : "+r"(x))
 
-int running_on_hw = 1;	/* vs. on ISS */
-
 /* Part of U-boot ABI: see head.S */
 int __initdata uboot_tag;
 char __initdata *uboot_arg;
@@ -42,26 +43,26 @@ struct cpuinfo_arc cpuinfo_arc700[NR_CPUS];
 static void read_arc_build_cfg_regs(void)
 {
 	struct bcr_perip uncached_space;
+	struct bcr_generic bcr;
 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
 	FIX_PTR(cpu);
 
 	READ_BCR(AUX_IDENTITY, cpu->core);
+	READ_BCR(ARC_REG_ISA_CFG_BCR, cpu->isa);
 
-	cpu->timers = read_aux_reg(ARC_REG_TIMERS_BCR);
+	READ_BCR(ARC_REG_TIMERS_BCR, cpu->timers);
 	cpu->vec_base = read_aux_reg(AUX_INTR_VEC_BASE);
 
 	READ_BCR(ARC_REG_D_UNCACH_BCR, uncached_space);
 	cpu->uncached_base = uncached_space.start << 24;
 
-	cpu->extn.mul = read_aux_reg(ARC_REG_MUL_BCR);
-	cpu->extn.swap = read_aux_reg(ARC_REG_SWAP_BCR);
-	cpu->extn.norm = read_aux_reg(ARC_REG_NORM_BCR);
-	cpu->extn.minmax = read_aux_reg(ARC_REG_MIXMAX_BCR);
-	cpu->extn.barrel = read_aux_reg(ARC_REG_BARREL_BCR);
-	READ_BCR(ARC_REG_MAC_BCR, cpu->extn_mac_mul);
+	READ_BCR(ARC_REG_MUL_BCR, cpu->extn_mpy);
 
-	cpu->extn.ext_arith = read_aux_reg(ARC_REG_EXTARITH_BCR);
-	cpu->extn.crc = read_aux_reg(ARC_REG_CRC_BCR);
+	cpu->extn.norm = read_aux_reg(ARC_REG_NORM_BCR) > 1 ? 1 : 0; /* 2,3 */
+	cpu->extn.barrel = read_aux_reg(ARC_REG_BARREL_BCR) > 1 ? 1 : 0; /* 2,3 */
+	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 */
 
 	/* Note that we read the CCM BCRs independent of kernel config
 	 * This is to catch the cases where user doesn't know that
@@ -95,43 +96,76 @@ static void read_arc_build_cfg_regs(void)
 	read_decode_mmu_bcr();
 	read_decode_cache_bcr();
 
-	READ_BCR(ARC_REG_FP_BCR, cpu->fp);
-	READ_BCR(ARC_REG_DPFP_BCR, cpu->dpfp);
+	{
+		struct bcr_fp_arcompact sp, dp;
+		struct bcr_bpu_arcompact bpu;
+
+		READ_BCR(ARC_REG_FP_BCR, sp);
+		READ_BCR(ARC_REG_DPFP_BCR, dp);
+		cpu->extn.fpu_sp = sp.ver ? 1 : 0;
+		cpu->extn.fpu_dp = dp.ver ? 1 : 0;
+
+		READ_BCR(ARC_REG_BPU_BCR, bpu);
+		cpu->bpu.ver = bpu.ver;
+		cpu->bpu.full = bpu.fam ? 1 : 0;
+		if (bpu.ent) {
+			cpu->bpu.num_cache = 256 << (bpu.ent - 1);
+			cpu->bpu.num_pred = 256 << (bpu.ent - 1);
+		}
+	}
+
+	READ_BCR(ARC_REG_AP_BCR, bcr);
+	cpu->extn.ap = bcr.ver ? 1 : 0;
+
+	READ_BCR(ARC_REG_SMART_BCR, bcr);
+	cpu->extn.smart = bcr.ver ? 1 : 0;
+
+	cpu->extn.debug = cpu->extn.ap | cpu->extn.smart;
 }
 
 static const struct cpuinfo_data arc_cpu_tbl[] = {
-	{ {0x10, "ARCTangent A5"}, 0x1F},
 	{ {0x20, "ARC 600"      }, 0x2F},
 	{ {0x30, "ARC 700"      }, 0x33},
 	{ {0x34, "ARC 700 R4.10"}, 0x34},
+	{ {0x35, "ARC 700 R4.11"}, 0x35},
 	{ {0x00, NULL		} }
 };
 
+#define IS_AVAIL1(v, str)	((v) ? str : "")
+#define IS_USED(cfg)		(IS_ENABLED(cfg) ? "" : "(not used) ")
+#define IS_AVAIL2(v, str, cfg)  IS_AVAIL1(v, str), IS_AVAIL1(v, IS_USED(cfg))
+
 static char *arc_cpu_mumbojumbo(int cpu_id, char *buf, int len)
 {
-	int n = 0;
 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id];
 	struct bcr_identity *core = &cpu->core;
 	const struct cpuinfo_data *tbl;
-	int be = 0;
-#ifdef CONFIG_CPU_BIG_ENDIAN
-	be = 1;
-#endif
+	char *isa_nm;
+	int i, be, atomic;
+	int n = 0;
+
 	FIX_PTR(cpu);
 
+	{
+		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);
+	}
+
 	n += scnprintf(buf + n, len - n,
-		       "\nARC IDENTITY\t: Family [%#02x]"
-		       " Cpu-id [%#02x] Chip-id [%#4x]\n",
-		       core->family, core->cpu_id,
-		       core->chip_id);
+		       "\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\t: %s %s\n",
-				       tbl->info.str,
-				       be ? "[Big Endian]" : "");
+				       "processor [%d]\t: %s (%s ISA) %s\n",
+				       cpu_id, tbl->info.str, isa_nm,
+				       IS_AVAIL1(be, "[Big-Endian]"));
 			break;
 		}
 	}
@@ -143,34 +177,35 @@ static char *arc_cpu_mumbojumbo(int cpu_id, char *buf, int len)
 		       (unsigned int)(arc_get_core_freq() / 1000000),
 		       (unsigned int)(arc_get_core_freq() / 10000) % 100);
 
-	n += scnprintf(buf + n, len - n, "Timers\t\t: %s %s\n",
-		       (cpu->timers & 0x200) ? "TIMER1" : "",
-		       (cpu->timers & 0x100) ? "TIMER0" : "");
+	n += scnprintf(buf + n, len - n, "Timers\t\t: %s%s%s%s\nISA Extn\t: ",
+		       IS_AVAIL1(cpu->timers.t0, "Timer0 "),
+		       IS_AVAIL1(cpu->timers.t1, "Timer1 "),
+		       IS_AVAIL2(cpu->timers.rtsc, "64-bit RTSC ", CONFIG_ARC_HAS_RTSC));
 
-	n += scnprintf(buf + n, len - n, "Vect Tbl Base\t: %#x\n",
-		       cpu->vec_base);
+	n += i = scnprintf(buf + n, len - n, "%s%s",
+			   IS_AVAIL2(atomic, "atomic ", CONFIG_ARC_HAS_LLSC));
 
-	n += scnprintf(buf + n, len - n, "UNCACHED Base\t: %#x\n",
-		       cpu->uncached_base);
+	if (i)
+		n += scnprintf(buf + n, len - n, "\n\t\t: ");
 
-	return buf;
-}
+	n += scnprintf(buf + n, len - n, "%s%s%s%s%s%s%s%s\n",
+		       IS_AVAIL1(cpu->extn_mpy.ver, "mpy "),
+		       IS_AVAIL1(cpu->extn.norm, "norm "),
+		       IS_AVAIL1(cpu->extn.barrel, "barrel-shift "),
+		       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));
 
-static const struct id_to_str mul_type_nm[] = {
-	{ 0x0, "N/A"},
-	{ 0x1, "32x32 (spl Result Reg)" },
-	{ 0x2, "32x32 (ANY Result Reg)" }
-};
+	if (cpu->bpu.ver)
+		n += scnprintf(buf + n, len - n,
+			      "BPU\t\t: %s%s match, cache:%d, Predict Table:%d\n",
+			      IS_AVAIL1(cpu->bpu.full, "full"),
+			      IS_AVAIL1(!cpu->bpu.full, "partial"),
+			      cpu->bpu.num_cache, cpu->bpu.num_pred);
 
-static const struct id_to_str mac_mul_nm[] = {
-	{0x0, "N/A"},
-	{0x1, "N/A"},
-	{0x2, "Dual 16 x 16"},
-	{0x3, "N/A"},
-	{0x4, "32x16"},
-	{0x5, "N/A"},
-	{0x6, "Dual 16x16 and 32x16"}
-};
+	return buf;
+}
 
 static char *arc_extn_mumbojumbo(int cpu_id, char *buf, int len)
 {
@@ -178,67 +213,46 @@ static char *arc_extn_mumbojumbo(int cpu_id, char *buf, int len)
 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id];
 
 	FIX_PTR(cpu);
-#define IS_AVAIL1(var, str)	((var) ? str : "")
-#define IS_AVAIL2(var, str)	((var == 0x2) ? str : "")
-#define IS_USED(cfg)		(IS_ENABLED(cfg) ? "(in-use)" : "(not used)")
 
 	n += scnprintf(buf + n, len - n,
-		       "Extn [700-Base]\t: %s %s %s %s %s %s\n",
-		       IS_AVAIL2(cpu->extn.norm, "norm,"),
-		       IS_AVAIL2(cpu->extn.barrel, "barrel-shift,"),
-		       IS_AVAIL1(cpu->extn.swap, "swap,"),
-		       IS_AVAIL2(cpu->extn.minmax, "minmax,"),
-		       IS_AVAIL1(cpu->extn.crc, "crc,"),
-		       IS_AVAIL2(cpu->extn.ext_arith, "ext-arith"));
-
-	n += scnprintf(buf + n, len - n, "Extn [700-MPY]\t: %s",
-		       mul_type_nm[cpu->extn.mul].str);
-
-	n += scnprintf(buf + n, len - n, "   MAC MPY: %s\n",
-		       mac_mul_nm[cpu->extn_mac_mul.type].str);
-
-	if (cpu->core.family == 0x34) {
-		n += scnprintf(buf + n, len - n,
-		"Extn [700-4.10]\t: LLOCK/SCOND %s, SWAPE %s, RTSC %s\n",
-			       IS_USED(CONFIG_ARC_HAS_LLSC),
-			       IS_USED(CONFIG_ARC_HAS_SWAPE),
-			       IS_USED(CONFIG_ARC_HAS_RTSC));
-	}
-
-	n += scnprintf(buf + n, len - n, "Extn [CCM]\t: %s",
-		       !(cpu->dccm.sz || cpu->iccm.sz) ? "N/A" : "");
-
-	if (cpu->dccm.sz)
-		n += scnprintf(buf + n, len - n, "DCCM: @ %x, %d KB ",
-			       cpu->dccm.base_addr, TO_KB(cpu->dccm.sz));
-
-	if (cpu->iccm.sz)
-		n += scnprintf(buf + n, len - n, "ICCM: @ %x, %d KB",
+		       "Vector Table\t: %#x\nUncached Base\t: %#x\n",
+		       cpu->vec_base, cpu->uncached_base);
+
+	if (cpu->extn.fpu_sp || cpu->extn.fpu_dp)
+		n += scnprintf(buf + n, len - n, "FPU\t\t: %s%s\n",
+			       IS_AVAIL1(cpu->extn.fpu_sp, "SP "),
+			       IS_AVAIL1(cpu->extn.fpu_dp, "DP "));
+
+	if (cpu->extn.debug)
+		n += scnprintf(buf + n, len - n, "DEBUG\t\t: %s%s%s\n",
+			       IS_AVAIL1(cpu->extn.ap, "ActionPoint "),
+			       IS_AVAIL1(cpu->extn.smart, "smaRT "),
+			       IS_AVAIL1(cpu->extn.rtt, "RTT "));
+
+	if (cpu->dccm.sz || cpu->iccm.sz)
+		n += scnprintf(buf + n, len - n, "Extn [CCM]\t: DCCM @ %x, %d KB / ICCM: @ %x, %d KB\n",
+			       cpu->dccm.base_addr, TO_KB(cpu->dccm.sz),
 			       cpu->iccm.base_addr, TO_KB(cpu->iccm.sz));
 
-	n += scnprintf(buf + n, len - n, "\nExtn [FPU]\t: %s",
-		       !(cpu->fp.ver || cpu->dpfp.ver) ? "N/A" : "");
-
-	if (cpu->fp.ver)
-		n += scnprintf(buf + n, len - n, "SP [v%d] %s",
-			       cpu->fp.ver, cpu->fp.fast ? "(fast)" : "");
-
-	if (cpu->dpfp.ver)
-		n += scnprintf(buf + n, len - n, "DP [v%d] %s",
-			       cpu->dpfp.ver, cpu->dpfp.fast ? "(fast)" : "");
-
-	n += scnprintf(buf + n, len - n, "\n");
-
 	n += scnprintf(buf + n, len - n,
 		       "OS ABI [v3]\t: no-legacy-syscalls\n");
 
 	return buf;
 }
 
-static void arc_chk_ccms(void)
+static void arc_chk_core_config(void)
 {
-#if defined(CONFIG_ARC_HAS_DCCM) || defined(CONFIG_ARC_HAS_ICCM)
 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
+	int fpu_enabled;
+
+	if (!cpu->timers.t0)
+		panic("Timer0 is not present!\n");
+
+	if (!cpu->timers.t1)
+		panic("Timer1 is not present!\n");
+
+	if (IS_ENABLED(CONFIG_ARC_HAS_RTSC) && !cpu->timers.rtsc)
+		panic("RTSC is not present\n");
 
 #ifdef CONFIG_ARC_HAS_DCCM
 	/*
@@ -256,33 +270,20 @@ static void arc_chk_ccms(void)
 	if (CONFIG_ARC_ICCM_SZ != cpu->iccm.sz)
 		panic("Linux built with incorrect ICCM Size\n");
 #endif
-#endif
-}
 
-/*
- * Ensure that FP hardware and kernel config match
- * -If hardware contains DPFP, kernel needs to save/restore FPU state
- *  across context switches
- * -If hardware lacks DPFP, but kernel configured to save FPU state then
- *  kernel trying to access non-existant DPFP regs will crash
- *
- * We only check for Dbl precision Floating Point, because only DPFP
- * hardware has dedicated regs which need to be saved/restored on ctx-sw
- * (Single Precision uses core regs), thus kernel is kind of oblivious to it
- */
-static void arc_chk_fpu(void)
-{
-	struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
+	/*
+	 * FP hardware/software config sanity
+	 * -If hardware contains DPFP, kernel needs to save/restore FPU state
+	 * -If not, it will crash trying to save/restore the non-existant regs
+	 *
+	 * (only DPDP checked since SP has no arch visible regs)
+	 */
+	fpu_enabled = IS_ENABLED(CONFIG_ARC_FPU_SAVE_RESTORE);
 
-	if (cpu->dpfp.ver) {
-#ifndef CONFIG_ARC_FPU_SAVE_RESTORE
-		pr_warn("DPFP support broken in this kernel...\n");
-#endif
-	} else {
-#ifdef CONFIG_ARC_FPU_SAVE_RESTORE
-		panic("H/w lacks DPFP support, apps won't work\n");
-#endif
-	}
+	if (cpu->extn.fpu_dp && !fpu_enabled)
+		pr_warn("CONFIG_ARC_FPU_SAVE_RESTORE needed for working apps\n");
+	else if (!cpu->extn.fpu_dp && fpu_enabled)
+		panic("FPU non-existent, disable CONFIG_ARC_FPU_SAVE_RESTORE\n");
 }
 
 /*
@@ -303,15 +304,11 @@ void setup_processor(void)
 
 	arc_mmu_init();
 	arc_cache_init();
-	arc_chk_ccms();
 
 	printk(arc_extn_mumbojumbo(cpu_id, str, sizeof(str)));
-
-#ifdef CONFIG_SMP
 	printk(arc_platform_smp_cpuinfo());
-#endif
 
-	arc_chk_fpu();
+	arc_chk_core_config();
 }
 
 static inline int is_kernel(unsigned long addr)
@@ -360,11 +357,7 @@ void __init setup_arch(char **cmdline_p)
 		machine_desc->init_early();
 
 	setup_processor();
-
-#ifdef CONFIG_SMP
 	smp_init_cpus();
-#endif
-
 	setup_arch_memory();
 
 	/* copy flat DT out of .init and then unflatten it */
@@ -385,7 +378,13 @@ void __init setup_arch(char **cmdline_p)
 
 static int __init customize_machine(void)
 {
-	/* Add platform devices */
+	of_clk_init(NULL);
+	/*
+	 * Traverses flattened DeviceTree - registering platform devices
+	 * (if any) complete with their resources
+	 */
+	of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
+
 	if (machine_desc->init_machine)
 		machine_desc->init_machine();
 
@@ -419,19 +418,14 @@ static int show_cpuinfo(struct seq_file *m, void *v)
 
 	seq_printf(m, arc_cpu_mumbojumbo(cpu_id, str, PAGE_SIZE));
 
-	seq_printf(m, "Bogo MIPS : \t%lu.%02lu\n",
+	seq_printf(m, "Bogo MIPS\t: %lu.%02lu\n",
 		   loops_per_jiffy / (500000 / HZ),
 		   (loops_per_jiffy / (5000 / HZ)) % 100);
 
 	seq_printf(m, arc_mmu_mumbojumbo(cpu_id, str, PAGE_SIZE));
-
 	seq_printf(m, arc_cache_mumbojumbo(cpu_id, str, PAGE_SIZE));
-
 	seq_printf(m, arc_extn_mumbojumbo(cpu_id, str, PAGE_SIZE));
-
-#ifdef CONFIG_SMP
 	seq_printf(m, arc_platform_smp_cpuinfo());
-#endif
 
 	free_page((unsigned long)str);
 done:
diff --git a/arch/arc/kernel/signal.c b/arch/arc/kernel/signal.c
index 7e95e1a8651..cb3142a2d40 100644
--- a/arch/arc/kernel/signal.c
+++ b/arch/arc/kernel/signal.c
@@ -141,17 +141,13 @@ badframe:
 /*
  * Determine which stack to use..
  */
-static inline void __user *get_sigframe(struct k_sigaction *ka,
+static inline void __user *get_sigframe(struct ksignal *ksig,
 					struct pt_regs *regs,
 					unsigned long framesize)
 {
-	unsigned long sp = regs->sp;
+	unsigned long sp = sigsp(regs->sp, ksig);
 	void __user *frame;
 
-	/* This is the X/Open sanctioned signal stack switching */
-	if ((ka->sa.sa_flags & SA_ONSTACK) && !sas_ss_flags(sp))
-		sp = current->sas_ss_sp + current->sas_ss_size;
-
 	/* No matter what happens, 'sp' must be word
 	 * aligned otherwise nasty things could happen
 	 */
@@ -179,14 +175,13 @@ static inline int map_sig(int sig)
 }
 
 static int
-setup_rt_frame(int signo, struct k_sigaction *ka, siginfo_t *info,
-	       sigset_t *set, struct pt_regs *regs)
+setup_rt_frame(struct ksignal *ksig, sigset_t *set, struct pt_regs *regs)
 {
 	struct rt_sigframe __user *sf;
 	unsigned int magic = 0;
 	int err = 0;
 
-	sf = get_sigframe(ka, regs, sizeof(struct rt_sigframe));
+	sf = get_sigframe(ksig, regs, sizeof(struct rt_sigframe));
 	if (!sf)
 		return 1;
 
@@ -205,8 +200,8 @@ setup_rt_frame(int signo, struct k_sigaction *ka, siginfo_t *info,
 	 *  #2: struct siginfo
 	 *  #3: struct ucontext (completely populated)
 	 */
-	if (unlikely(ka->sa.sa_flags & SA_SIGINFO)) {
-		err |= copy_siginfo_to_user(&sf->info, info);
+	if (unlikely(ksig->ka.sa.sa_flags & SA_SIGINFO)) {
+		err |= copy_siginfo_to_user(&sf->info, &ksig->info);
 		err |= __put_user(0, &sf->uc.uc_flags);
 		err |= __put_user(NULL, &sf->uc.uc_link);
 		err |= __save_altstack(&sf->uc.uc_stack, regs->sp);
@@ -227,16 +222,16 @@ setup_rt_frame(int signo, struct k_sigaction *ka, siginfo_t *info,
 		return err;
 
 	/* #1 arg to the user Signal handler */
-	regs->r0 = map_sig(signo);
+	regs->r0 = map_sig(ksig->sig);
 
 	/* setup PC of user space signal handler */
-	regs->ret = (unsigned long)ka->sa.sa_handler;
+	regs->ret = (unsigned long)ksig->ka.sa.sa_handler;
 
 	/*
 	 * handler returns using sigreturn stub provided already by userpsace
 	 */
-	BUG_ON(!(ka->sa.sa_flags & SA_RESTORER));
-	regs->blink = (unsigned long)ka->sa.sa_restorer;
+	BUG_ON(!(ksig->ka.sa.sa_flags & SA_RESTORER));
+	regs->blink = (unsigned long)ksig->ka.sa.sa_restorer;
 
 	/* User Stack for signal handler will be above the frame just carved */
 	regs->sp = (unsigned long)sf;
@@ -298,38 +293,30 @@ static void arc_restart_syscall(struct k_sigaction *ka, struct pt_regs *regs)
  * OK, we're invoking a handler
  */
 static void
-handle_signal(unsigned long sig, struct k_sigaction *ka, siginfo_t *info,
-	      struct pt_regs *regs)
+handle_signal(struct ksignal *ksig, struct pt_regs *regs)
 {
 	sigset_t *oldset = sigmask_to_save();
 	int ret;
 
 	/* Set up the stack frame */
-	ret = setup_rt_frame(sig, ka, info, oldset, regs);
+	ret = setup_rt_frame(ksig, oldset, regs);
 
-	if (ret)
-		force_sigsegv(sig, current);
-	else
-		signal_delivered(sig, info, ka, regs, 0);
+	signal_setup_done(ret, ksig, 0);
 }
 
 void do_signal(struct pt_regs *regs)
 {
-	struct k_sigaction ka;
-	siginfo_t info;
-	int signr;
+	struct ksignal ksig;
 	int restart_scall;
 
-	signr = get_signal_to_deliver(&info, &ka, regs, NULL);
-
 	restart_scall = in_syscall(regs) && syscall_restartable(regs);
 
-	if (signr > 0) {
+	if (get_signal(&ksig)) {
 		if (restart_scall) {
-			arc_restart_syscall(&ka, regs);
+			arc_restart_syscall(&ksig.ka, regs);
 			syscall_wont_restart(regs);	/* No more restarts */
 		}
-		handle_signal(signr, &ka, &info, regs);
+		handle_signal(&ksig, regs);
 		return;
 	}
 
diff --git a/arch/arc/kernel/smp.c b/arch/arc/kernel/smp.c
index c802bb50060..d01df0c517a 100644
--- a/arch/arc/kernel/smp.c
+++ b/arch/arc/kernel/smp.c
@@ -12,23 +12,15 @@
  *    -- Initial Write (Borrowed heavily from ARM)
  */
 
-#include <linux/module.h>
-#include <linux/init.h>
 #include <linux/spinlock.h>
 #include <linux/sched.h>
 #include <linux/interrupt.h>
 #include <linux/profile.h>
-#include <linux/errno.h>
-#include <linux/err.h>
 #include <linux/mm.h>
 #include <linux/cpu.h>
-#include <linux/smp.h>
 #include <linux/irq.h>
-#include <linux/delay.h>
 #include <linux/atomic.h>
-#include <linux/percpu.h>
 #include <linux/cpumask.h>
-#include <linux/spinlock_types.h>
 #include <linux/reboot.h>
 #include <asm/processor.h>
 #include <asm/setup.h>
@@ -109,7 +101,7 @@ void __weak arc_platform_smp_wait_to_boot(int cpu)
 
 const char *arc_platform_smp_cpuinfo(void)
 {
-	return plat_smp_ops.info;
+	return plat_smp_ops.info ? : "";
 }
 
 /*
@@ -136,7 +128,7 @@ void start_kernel_secondary(void)
 	pr_info("## CPU%u LIVE ##: Executing Code...\n", cpu);
 
 	if (machine_desc->init_smp)
-		machine_desc->init_smp(smp_processor_id());
+		machine_desc->init_smp(cpu);
 
 	arc_local_timer_setup();
 
@@ -338,18 +330,11 @@ irqreturn_t do_IPI(int irq, void *dev_id)
  */
 static DEFINE_PER_CPU(int, ipi_dev);
 
-static struct irqaction arc_ipi_irq = {
-        .name    = "IPI Interrupt",
-        .flags   = IRQF_PERCPU,
-        .handler = do_IPI,
-};
-
 int smp_ipi_irq_setup(int cpu, int irq)
 {
-	if (!cpu)
-		return setup_irq(irq, &arc_ipi_irq);
-	else
-		arch_unmask_irq(irq);
+	int *dev = per_cpu_ptr(&ipi_dev, cpu);
+
+	arc_request_percpu_irq(irq, cpu, do_IPI, "IPI Interrupt", dev);
 
 	return 0;
 }
diff --git a/arch/arc/kernel/time.c b/arch/arc/kernel/time.c
index 36c2aa99436..dbe74f41801 100644
--- a/arch/arc/kernel/time.c
+++ b/arch/arc/kernel/time.c
@@ -144,12 +144,12 @@ static struct clocksource arc_counter = {
 /********** Clock Event Device *********/
 
 /*
- * Arm the timer to interrupt after @limit cycles
+ * Arm the timer to interrupt after @cycles
  * The distinction for oneshot/periodic is done in arc_event_timer_ack() below
  */
-static void arc_timer_event_setup(unsigned int limit)
+static void arc_timer_event_setup(unsigned int cycles)
 {
-	write_aux_reg(ARC_REG_TIMER0_LIMIT, limit);
+	write_aux_reg(ARC_REG_TIMER0_LIMIT, cycles);
 	write_aux_reg(ARC_REG_TIMER0_CNT, 0);	/* start from 0 */
 
 	write_aux_reg(ARC_REG_TIMER0_CTRL, TIMER_CTRL_IE | TIMER_CTRL_NH);
@@ -168,6 +168,10 @@ static void arc_clkevent_set_mode(enum clock_event_mode mode,
 {
 	switch (mode) {
 	case CLOCK_EVT_MODE_PERIODIC:
+                /*
+                 * At X Hz, 1 sec = 1000ms -> X cycles;
+                 *                    10ms -> X / 100 cycles
+                 */
 		arc_timer_event_setup(arc_get_core_freq() / HZ);
 		break;
 	case CLOCK_EVT_MODE_ONESHOT:
@@ -210,12 +214,6 @@ static irqreturn_t timer_irq_handler(int irq, void *dev_id)
 	return IRQ_HANDLED;
 }
 
-static struct irqaction arc_timer_irq = {
-	.name    = "Timer0 (clock-evt-dev)",
-	.flags   = IRQF_TIMER | IRQF_PERCPU,
-	.handler = timer_irq_handler,
-};
-
 /*
  * Setup the local event timer for @cpu
  */
@@ -228,15 +226,9 @@ void arc_local_timer_setup()
 	clockevents_config_and_register(evt, arc_get_core_freq(),
 					0, ARC_TIMER_MAX);
 
-	/*
-	 * setup the per-cpu timer IRQ handler - for all cpus
-	 * For non boot CPU explicitly unmask at intc
-	 * setup_irq() -> .. -> irq_startup() already does this on boot-cpu
-	 */
-	if (!cpu)
-		setup_irq(TIMER0_IRQ, &arc_timer_irq);
-	else
-		arch_unmask_irq(TIMER0_IRQ);
+	/* setup the per-cpu timer IRQ handler - for all cpus */
+	arc_request_percpu_irq(TIMER0_IRQ, cpu, timer_irq_handler,
+			       "Timer0 (per-cpu-tick)", evt);
 }
 
 /*