[PATCH v3 00/11] plat-eznps upstream cont. set 2

[PATCH v3 00/11] plat-eznps upstream cont. set 2

[Noam Camus]

From: Noam Camus <noamca@mellanox.com>

Change Log:
V2 -> V3
1) turn ARC prink's into pr_info as suggested by Vineet
2) For new command line argument (hs counter) shorten error massage to a single line,
   again as Vineet commented.

V1 -> V2
1) I added "Handle memory error as an exception" patch from previous set
   It now turn do_memory_error() into weak sybol.
   It is then overriden by NPS400 platform, to simply call die().
2) This set is now based on arc-next branch

Summary:
With this patch set I continue the effort of upstreaming the eznps platform for arch/arc.

It comprise of couple of patches from last set yet not accepted,
patches for HW erratas and some misc extensions such for HIGHMEM / NUMA.

This set got more generic ARC changes than previous set.
Additional ifdef seem like unavoidable, however it may seem Ugly.
Let's see if we need to do it more elegant.

Elad Kanfi (1):
  ARC: [plat-eznps] avoid toggling of DPC register

Liav Rehana (2):
  ARC: [plat-eznps] Update the init sequence of aux regs per cpu.
  ARC: [plat-eznps] handle dedicated AUX registers

Noam Camus (8):
  ARC: set level of log per CPU during boot to be info level
  ARC: send ipi to all cpus sharing task mm in case of page fault
  ARC: Allow irq threading
  ARC: Add CPU topology
  ARC: Support more than one PGDIR for KVADDR
  ARC: [NUMA] added CONFIG_NUMA for plat-eznps
  ARC: [plat-eznps] new command line argument for HW scheduler at MTM
  ARC: [plat-eznps] Save/Restore extra auxiliary registers

 Documentation/admin-guide/kernel-parameters.txt |    9 ++
 arch/arc/Kconfig                                |   48 +++++++++
 arch/arc/include/asm/Kbuild                     |    1 -
 arch/arc/include/asm/arcregs.h                  |    7 ++
 arch/arc/include/asm/cacheflush.h               |    3 +-
 arch/arc/include/asm/entry-compact.h            |   24 +++++
 arch/arc/include/asm/highmem.h                  |    8 +-
 arch/arc/include/asm/pgtable.h                  |    9 ++
 arch/arc/include/asm/processor.h                |    8 +-
 arch/arc/include/asm/ptrace.h                   |    5 +
 arch/arc/include/asm/switch_to.h                |   11 ++
 arch/arc/include/asm/topology.h                 |   40 +++++++
 arch/arc/kernel/Makefile                        |    1 +
 arch/arc/kernel/process.c                       |    4 +
 arch/arc/kernel/setup.c                         |   13 ++-
 arch/arc/kernel/smp.c                           |    5 +
 arch/arc/kernel/topology.c                      |  125 +++++++++++++++++++++++
 arch/arc/mm/cache.c                             |   14 ++-
 arch/arc/mm/fault.c                             |    8 ++
 arch/arc/mm/highmem.c                           |   16 ++-
 arch/arc/mm/init.c                              |    6 +
 arch/arc/mm/tlb.c                               |    4 +-
 arch/arc/mm/tlbex.S                             |   31 ++++++
 arch/arc/plat-eznps/Kconfig                     |   11 ++
 arch/arc/plat-eznps/Makefile                    |    2 +-
 arch/arc/plat-eznps/ctop.c                      |   33 ++++++
 arch/arc/plat-eznps/entry.S                     |    2 +-
 arch/arc/plat-eznps/include/plat/ctop.h         |    1 +
 arch/arc/plat-eznps/mtm.c                       |   58 ++++++++++-
 29 files changed, 481 insertions(+), 26 deletions(-)
 create mode 100644 arch/arc/include/asm/topology.h
 create mode 100644 arch/arc/kernel/topology.c
 create mode 100644 arch/arc/plat-eznps/ctop.c

[PATCH v3 01/11] ARC: set level of log per CPU during boot to be info level

[Noam Camus]

From: Noam Camus <noamca@mellanox.com>

Now it can be hidden by passing higher loglevel sevirity at cmdline
The reasons are:
1) speeding up boot time, becomes critical for many CPUs machine,
   e.g. NPS400 with 4K CPUs
2) shorten kernel log at boot time, again easy to scan for large
   scale machines such NPS400

Signed-off-by: Noam Camus <noamca@mellanox.com>
---
 arch/arc/kernel/setup.c |    6 +++---
 arch/arc/mm/cache.c     |    2 +-
 arch/arc/mm/tlb.c       |    2 +-
 3 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/arch/arc/kernel/setup.c b/arch/arc/kernel/setup.c
index fc8211f..de29ea9 100644
--- a/arch/arc/kernel/setup.c
+++ b/arch/arc/kernel/setup.c
@@ -385,13 +385,13 @@ void setup_processor(void)
 	read_arc_build_cfg_regs();
 	arc_init_IRQ();
 
-	printk(arc_cpu_mumbojumbo(cpu_id, str, sizeof(str)));
+	pr_info("%s", arc_cpu_mumbojumbo(cpu_id, str, sizeof(str)));
 
 	arc_mmu_init();
 	arc_cache_init();
 
-	printk(arc_extn_mumbojumbo(cpu_id, str, sizeof(str)));
-	printk(arc_platform_smp_cpuinfo());
+	pr_info("%s", arc_extn_mumbojumbo(cpu_id, str, sizeof(str)));
+	pr_info("%s", arc_platform_smp_cpuinfo());
 
 	arc_chk_core_config();
 }
diff --git a/arch/arc/mm/cache.c b/arch/arc/mm/cache.c
index a867575..bdb5227 100644
--- a/arch/arc/mm/cache.c
+++ b/arch/arc/mm/cache.c
@@ -1188,7 +1188,7 @@ void __ref arc_cache_init(void)
 	unsigned int __maybe_unused cpu = smp_processor_id();
 	char str[256];
 
-	printk(arc_cache_mumbojumbo(0, str, sizeof(str)));
+	pr_info("%s", arc_cache_mumbojumbo(0, str, sizeof(str)));
 
 	/*
 	 * Only master CPU needs to execute rest of function:
diff --git a/arch/arc/mm/tlb.c b/arch/arc/mm/tlb.c
index d0126fd..2b6da60 100644
--- a/arch/arc/mm/tlb.c
+++ b/arch/arc/mm/tlb.c
@@ -814,7 +814,7 @@ void arc_mmu_init(void)
 	char str[256];
 	struct cpuinfo_arc_mmu *mmu = &cpuinfo_arc700[smp_processor_id()].mmu;
 
-	printk(arc_mmu_mumbojumbo(0, str, sizeof(str)));
+	pr_info("%s", arc_mmu_mumbojumbo(0, str, sizeof(str)));
 
 	/*
 	 * Can't be done in processor.h due to header include depenedencies
-- 
1.7.1

[PATCH v3 02/11] ARC: send ipi to all cpus sharing task mm in case of page fault

[Noam Camus]

From: Noam Camus <noamca@mellanox.com>

This patch is derived due to performance issue.
The use case is a page fault that resides on more than the local cpu.
Trying to broadcast all CPUs results on performance degradation.
So we try to avoid this by sending only to the relevant CPUs.

Signed-off-by: Noam Camus <noamca@mellanox.com>
Reviewed-by: Alexey Brodkin <abrodkin@synopsys.com>
---
 arch/arc/include/asm/cacheflush.h |    3 ++-
 arch/arc/mm/cache.c               |   12 ++++++++++--
 arch/arc/mm/tlb.c                 |    2 +-
 3 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/arch/arc/include/asm/cacheflush.h b/arch/arc/include/asm/cacheflush.h
index fc662f4..716dba1 100644
--- a/arch/arc/include/asm/cacheflush.h
+++ b/arch/arc/include/asm/cacheflush.h
@@ -33,7 +33,8 @@
 
 void flush_icache_range(unsigned long kstart, unsigned long kend);
 void __sync_icache_dcache(phys_addr_t paddr, unsigned long vaddr, int len);
-void __inv_icache_page(phys_addr_t paddr, unsigned long vaddr);
+void __inv_icache_page(struct vm_area_struct *vma,
+		       phys_addr_t paddr, unsigned long vaddr);
 void __flush_dcache_page(phys_addr_t paddr, unsigned long vaddr);
 
 #define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
diff --git a/arch/arc/mm/cache.c b/arch/arc/mm/cache.c
index bdb5227..bfad0fa 100644
--- a/arch/arc/mm/cache.c
+++ b/arch/arc/mm/cache.c
@@ -934,9 +934,17 @@ void __sync_icache_dcache(phys_addr_t paddr, unsigned long vaddr, int len)
 }
 
 /* wrapper to compile time eliminate alignment checks in flush loop */
-void __inv_icache_page(phys_addr_t paddr, unsigned long vaddr)
+void __inv_icache_page(struct vm_area_struct *vma,
+		       phys_addr_t paddr, unsigned long vaddr)
 {
-	__ic_line_inv_vaddr(paddr, vaddr, PAGE_SIZE);
+	struct ic_inv_args ic_inv = {
+		.paddr	= paddr,
+		.vaddr	= vaddr,
+		.sz	= PAGE_SIZE
+	};
+
+	on_each_cpu_mask(mm_cpumask(vma->vm_mm),
+			 __ic_line_inv_vaddr_helper, &ic_inv, 1);
 }
 
 /*
diff --git a/arch/arc/mm/tlb.c b/arch/arc/mm/tlb.c
index 2b6da60..e298da9 100644
--- a/arch/arc/mm/tlb.c
+++ b/arch/arc/mm/tlb.c
@@ -626,7 +626,7 @@ void update_mmu_cache(struct vm_area_struct *vma, unsigned long vaddr_unaligned,
 
 			/* invalidate any existing icache lines (U-mapping) */
 			if (vma->vm_flags & VM_EXEC)
-				__inv_icache_page(paddr, vaddr);
+				__inv_icache_page(vma, paddr, vaddr);
 		}
 	}
 }
-- 
1.7.1

[PATCH v3 03/11] ARC: Allow irq threading

[Noam Camus]

From: Noam Camus <noamc@ezchip.com>

Working with NPS400 we noticed that there is a possibility of L1
interrupt nesting that may run out kernel stack.
The scenario include serving invoke_softirqs() from irq_exit()
and once local_irq_enable() called can hit another one before we
managed to restore last one and pop some place from kernel stack.

Serving softirqs at dedicated kernel thread may mitigate this.
We see that many architectures, including x86, behave like this.

Note 1: All interrupts which must be non threaded
should be marked IRQF_NO_THREAD.
Note 2: using kernel param "threadirqs" is needed to actually
turn this on. This configuration is only a preperation.

Signed-off-by: Noam Camus <noamc@ezchip.com>
---
 arch/arc/Kconfig |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
index a545969..f464f97 100644
--- a/arch/arc/Kconfig
+++ b/arch/arc/Kconfig
@@ -33,6 +33,7 @@ config ARC
 	select HAVE_OPROFILE
 	select HAVE_PERF_EVENTS
 	select HANDLE_DOMAIN_IRQ
+	select IRQ_FORCED_THREADING
 	select IRQ_DOMAIN
 	select MODULES_USE_ELF_RELA
 	select NO_BOOTMEM
-- 
1.7.1

[PATCH v3 04/11] ARC: Add CPU topology

[Noam Camus]

From: Noam Camus <noamca@mellanox.com>

Now it is used for NPS SoC for multi-core of 256 cores
and SMT of 16 HW threads per core.

This way with topology the scheduler is much efficient in
creating domains and later using them.

Signed-off-by: Noam Camus <noamca@mellanox.com>
---
 arch/arc/Kconfig                |   27 ++++++++
 arch/arc/include/asm/Kbuild     |    1 -
 arch/arc/include/asm/topology.h |   34 +++++++++++
 arch/arc/kernel/Makefile        |    1 +
 arch/arc/kernel/setup.c         |    4 +-
 arch/arc/kernel/smp.c           |    5 ++
 arch/arc/kernel/topology.c      |  125 +++++++++++++++++++++++++++++++++++++++
 7 files changed, 194 insertions(+), 3 deletions(-)
 create mode 100644 arch/arc/include/asm/topology.h
 create mode 100644 arch/arc/kernel/topology.c

diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
index f464f97..08a9003 100644
--- a/arch/arc/Kconfig
+++ b/arch/arc/Kconfig
@@ -202,6 +202,33 @@ config ARC_SMP_HALT_ON_RESET
 	  at designated entry point. For other case, all jump to common
 	  entry point and spin wait for Master's signal.
 
+config NPS_CPU_TOPOLOGY
+	bool "Support cpu topology definition"
+	depends on EZNPS_MTM_EXT
+	default y
+	help
+	  Support NPS cpu topology definition.
+	  NPS400 got 16 clusters of cores.
+	  NPS400 cluster got 16 cores.
+	  NPS core got 16 symetrical threads.
+	  Totally there are such 4096 threads (NR_CPUS=4096)
+
+config SCHED_MC
+	bool "Multi-core scheduler support"
+	depends on NPS_CPU_TOPOLOGY
+	help
+	  Multi-core scheduler support improves the CPU scheduler's decision
+	  making when dealing with multi-core CPU chips at a cost of slightly
+	  increased overhead in some places. If unsure say N here.
+
+config SCHED_SMT
+	bool "SMT scheduler support"
+	depends on NPS_CPU_TOPOLOGY
+	help
+	  Improves the CPU scheduler's decision making when dealing with
+	  MultiThreading at a cost of slightly increased overhead in some
+	  places. If unsure say N here.
+
 endif	#SMP
 
 config ARC_MCIP
diff --git a/arch/arc/include/asm/Kbuild b/arch/arc/include/asm/Kbuild
index 7bee4e4..d8cb607 100644
--- a/arch/arc/include/asm/Kbuild
+++ b/arch/arc/include/asm/Kbuild
@@ -43,7 +43,6 @@ generic-y += stat.h
 generic-y += statfs.h
 generic-y += termbits.h
 generic-y += termios.h
-generic-y += topology.h
 generic-y += trace_clock.h
 generic-y += types.h
 generic-y += ucontext.h
diff --git a/arch/arc/include/asm/topology.h b/arch/arc/include/asm/topology.h
new file mode 100644
index 0000000..a9be3f8
--- /dev/null
+++ b/arch/arc/include/asm/topology.h
@@ -0,0 +1,34 @@
+#ifndef _ASM_ARC_TOPOLOGY_H
+#define _ASM_ARC_TOPOLOGY_H
+
+#ifdef CONFIG_NPS_CPU_TOPOLOGY
+
+#include <linux/cpumask.h>
+
+struct cputopo_nps {
+	int thread_id;
+	int core_id;
+	cpumask_t thread_sibling;
+	cpumask_t core_sibling;
+};
+
+extern struct cputopo_nps cpu_topology[NR_CPUS];
+
+#define topology_core_id(cpu)          (cpu_topology[cpu].core_id)
+#define topology_core_cpumask(cpu)     (&cpu_topology[cpu].core_sibling)
+#define topology_sibling_cpumask(cpu)  (&cpu_topology[cpu].thread_sibling)
+
+void init_cpu_topology(void);
+void store_cpu_topology(unsigned int cpuid);
+const struct cpumask *cpu_coregroup_mask(int cpu);
+
+#else
+
+static inline void init_cpu_topology(void) { }
+static inline void store_cpu_topology(unsigned int cpuid) { }
+
+#endif
+
+#include <asm-generic/topology.h>
+
+#endif /* _ASM_ARC_TOPOLOGY_H */
diff --git a/arch/arc/kernel/Makefile b/arch/arc/kernel/Makefile
index 8942c5c..46af80a 100644
--- a/arch/arc/kernel/Makefile
+++ b/arch/arc/kernel/Makefile
@@ -23,6 +23,7 @@ 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
+obj-$(CONFIG_NPS_CPU_TOPOLOGY)		+= topology.o
 
 obj-$(CONFIG_ARC_FPU_SAVE_RESTORE)	+= fpu.o
 CFLAGS_fpu.o   += -mdpfp
diff --git a/arch/arc/kernel/setup.c b/arch/arc/kernel/setup.c
index de29ea9..379ebda 100644
--- a/arch/arc/kernel/setup.c
+++ b/arch/arc/kernel/setup.c
@@ -571,14 +571,14 @@ static void c_stop(struct seq_file *m, void *v)
 	.show	= show_cpuinfo
 };
 
-static DEFINE_PER_CPU(struct cpu, cpu_topology);
+static DEFINE_PER_CPU(struct cpu, cpu_topo_info);
 
 static int __init topology_init(void)
 {
 	int cpu;
 
 	for_each_present_cpu(cpu)
-	    register_cpu(&per_cpu(cpu_topology, cpu), cpu);
+		register_cpu(&per_cpu(cpu_topo_info, cpu), cpu);
 
 	return 0;
 }
diff --git a/arch/arc/kernel/smp.c b/arch/arc/kernel/smp.c
index f462671..91668c5 100644
--- a/arch/arc/kernel/smp.c
+++ b/arch/arc/kernel/smp.c
@@ -67,6 +67,9 @@ void __init smp_prepare_cpus(unsigned int max_cpus)
 {
 	int i;
 
+	init_cpu_topology();
+	store_cpu_topology(smp_processor_id());
+
 	/*
 	 * if platform didn't set the present map already, do it now
 	 * boot cpu is set to present already by init/main.c
@@ -151,6 +154,8 @@ void start_kernel_secondary(void)
 	if (machine_desc->init_per_cpu)
 		machine_desc->init_per_cpu(cpu);
 
+	store_cpu_topology(cpu);
+
 	notify_cpu_starting(cpu);
 	set_cpu_online(cpu, true);
 
diff --git a/arch/arc/kernel/topology.c b/arch/arc/kernel/topology.c
new file mode 100644
index 0000000..3feb7c9
--- /dev/null
+++ b/arch/arc/kernel/topology.c
@@ -0,0 +1,125 @@
+/*
+ * Copyright (C) 2015 Synopsys, Inc. (www.synopsys.com)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/cpu.h>
+#include <linux/cpumask.h>
+#include <linux/export.h>
+#include <linux/init.h>
+#include <linux/percpu.h>
+#include <linux/node.h>
+#include <linux/nodemask.h>
+#include <linux/of.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/sched/topology.h>
+#include <plat/smp.h>
+
+/*
+ * cpu topology table
+ */
+struct cputopo_nps cpu_topology[NR_CPUS];
+EXPORT_SYMBOL_GPL(cpu_topology);
+
+const struct cpumask *cpu_coregroup_mask(int cpu)
+{
+	return &cpu_topology[cpu].core_sibling;
+}
+
+static void update_siblings_masks(unsigned int cpuid)
+{
+	struct cputopo_nps *cpu_topo, *cpuid_topo = &cpu_topology[cpuid];
+	int cpu;
+	struct global_id global_topo, global_id_topo;
+
+	global_id_topo.value = cpuid;
+
+	/* update core and thread sibling masks */
+	for_each_possible_cpu(cpu) {
+		cpu_topo = &cpu_topology[cpu];
+		global_topo.value = cpu;
+
+		if (global_id_topo.cluster != global_topo.cluster)
+			continue;
+
+		cpumask_set_cpu(cpuid, &cpu_topo->core_sibling);
+		if (cpu != cpuid)
+			cpumask_set_cpu(cpu, &cpuid_topo->core_sibling);
+
+		if (cpuid_topo->core_id != cpu_topo->core_id)
+			continue;
+
+		cpumask_set_cpu(cpuid, &cpu_topo->thread_sibling);
+		if (cpu != cpuid)
+			cpumask_set_cpu(cpu, &cpuid_topo->thread_sibling);
+	}
+
+	/* Do not proceed before masks are written */
+	smp_wmb();
+}
+
+/*
+ * store_cpu_topology is called at boot when only one cpu is running
+ * and with the mutex cpu_hotplug.lock locked, when several cpus have booted,
+ * which prevents simultaneous write access to cpu_topology array
+ */
+void store_cpu_topology(unsigned int cpuid)
+{
+	struct cputopo_nps *cpuid_topo = &cpu_topology[cpuid];
+	struct global_id gid;
+
+	/* If the cpu topology has been already set, just return */
+	if (cpuid_topo->core_id != -1)
+		return;
+
+	gid.value = cpuid;
+
+	cpuid_topo->thread_id = gid.thread;
+	cpuid_topo->core_id = ((gid.cluster << 4) | gid.core);
+
+	update_siblings_masks(cpuid);
+
+	pr_debug("CPU%u: thread %d, core %d\n",
+		 cpuid, cpu_topology[cpuid].thread_id,
+		 cpu_topology[cpuid].core_id);
+}
+
+static struct sched_domain_topology_level nps_topology[] = {
+#ifdef CONFIG_SCHED_SMT
+	{ cpu_smt_mask, cpu_smt_flags, SD_INIT_NAME(SMT) },
+#endif
+#ifdef CONFIG_SCHED_MC
+	{ cpu_coregroup_mask, cpu_core_flags, SD_INIT_NAME(MC) },
+#endif
+	{ cpu_cpu_mask, SD_INIT_NAME(DIE) },
+	{ NULL, },
+};
+
+/*
+ * init_cpu_topology is called at boot when only one cpu is running
+ * which prevent simultaneous write access to cpu_topology array
+ */
+void __init init_cpu_topology(void)
+{
+	unsigned int cpu;
+
+	/* init core mask */
+	for_each_possible_cpu(cpu) {
+		struct cputopo_nps *cpu_topo = &(cpu_topology[cpu]);
+
+		cpu_topo->thread_id = -1;
+		cpu_topo->core_id =  -1;
+		cpumask_clear(&cpu_topo->core_sibling);
+		cpumask_clear(&cpu_topo->thread_sibling);
+	}
+
+	/* Do not proceed before masks are written */
+	smp_wmb();
+
+	/* Set scheduler topology descriptor */
+	set_sched_topology(nps_topology);
+}
-- 
1.7.1

[PATCH v3 05/11] ARC: Support more than one PGDIR for KVADDR

[Noam Camus]

From: Noam Camus <noamca@mellanox.com>

This way FIXMAP can have 2 PTEs per CPU even for
NR_CPUS=4096

For the extreme case like in eznps platform We use
all gutter between kernel and user.

Signed-off-by: Noam Camus <noamca@mellanox.com>
---
 arch/arc/Kconfig                 |   11 +++++++++++
 arch/arc/include/asm/highmem.h   |    8 +++++---
 arch/arc/include/asm/pgtable.h   |    9 +++++++++
 arch/arc/include/asm/processor.h |    5 +++--
 arch/arc/mm/fault.c              |    8 ++++++++
 arch/arc/mm/highmem.c            |   16 +++++++++++-----
 arch/arc/mm/tlbex.S              |   31 +++++++++++++++++++++++++++++++
 7 files changed, 78 insertions(+), 10 deletions(-)

diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
index 08a9003..982bd18 100644
--- a/arch/arc/Kconfig
+++ b/arch/arc/Kconfig
@@ -477,6 +477,17 @@ config ARC_HAS_PAE40
 	  Enable access to physical memory beyond 4G, only supported on
 	  ARC cores with 40 bit Physical Addressing support
 
+config HIGHMEM_PGDS_SHIFT
+	int "log num of PGDs for HIGHMEM"
+	range 0 5
+	default "0" if !ARC_PLAT_EZNPS || !HIGHMEM
+	default "5" if ARC_PLAT_EZNPS
+	help
+	  This way we can map more pages for HIGHMEM.
+	  Single PGD (2M) is supporting 256 PTEs (8K PAGE_SIZE)
+	  For FIXMAP where at least 2 PTEs are needed per CPU
+	  large NR_CPUS e.g. 4096 will consume 32 PGDs
+
 config ARCH_PHYS_ADDR_T_64BIT
 	def_bool ARC_HAS_PAE40
 
diff --git a/arch/arc/include/asm/highmem.h b/arch/arc/include/asm/highmem.h
index b1585c9..c5cb473 100644
--- a/arch/arc/include/asm/highmem.h
+++ b/arch/arc/include/asm/highmem.h
@@ -17,13 +17,13 @@
 
 /* start after vmalloc area */
 #define FIXMAP_BASE		(PAGE_OFFSET - FIXMAP_SIZE - PKMAP_SIZE)
-#define FIXMAP_SIZE		PGDIR_SIZE	/* only 1 PGD worth */
-#define KM_TYPE_NR		((FIXMAP_SIZE >> PAGE_SHIFT)/NR_CPUS)
+#define FIXMAP_SIZE		(PGDIR_SIZE * _BITUL(CONFIG_HIGHMEM_PGDS_SHIFT))
+#define KM_TYPE_NR		(((FIXMAP_SIZE >> PAGE_SHIFT)/NR_CPUS) > 2 ?: 2)
 #define FIXMAP_ADDR(nr)		(FIXMAP_BASE + ((nr) << PAGE_SHIFT))
 
 /* start after fixmap area */
 #define PKMAP_BASE		(FIXMAP_BASE + FIXMAP_SIZE)
-#define PKMAP_SIZE		PGDIR_SIZE
+#define PKMAP_SIZE		(PGDIR_SIZE * _BITUL(CONFIG_HIGHMEM_PGDS_SHIFT))
 #define LAST_PKMAP		(PKMAP_SIZE >> PAGE_SHIFT)
 #define LAST_PKMAP_MASK		(LAST_PKMAP - 1)
 #define PKMAP_ADDR(nr)		(PKMAP_BASE + ((nr) << PAGE_SHIFT))
@@ -32,6 +32,7 @@
 #define kmap_prot		PAGE_KERNEL
 
 
+#ifndef __ASSEMBLY__
 #include <asm/cacheflush.h>
 
 extern void *kmap(struct page *page);
@@ -54,6 +55,7 @@ static inline void kunmap(struct page *page)
 		return;
 	kunmap_high(page);
 }
+#endif /* __ASSEMBLY__  */
 
 
 #endif
diff --git a/arch/arc/include/asm/pgtable.h b/arch/arc/include/asm/pgtable.h
index 08fe338..d08e207 100644
--- a/arch/arc/include/asm/pgtable.h
+++ b/arch/arc/include/asm/pgtable.h
@@ -224,6 +224,8 @@
 #define	PTRS_PER_PTE	_BITUL(BITS_FOR_PTE)
 #define	PTRS_PER_PGD	_BITUL(BITS_FOR_PGD)
 
+#define PTRS_HMEM_PTE	_BITUL(BITS_FOR_PTE + CONFIG_HIGHMEM_PGDS_SHIFT)
+
 /*
  * Number of entries a user land program use.
  * TASK_SIZE is the maximum vaddr that can be used by a userland program.
@@ -285,7 +287,14 @@ static inline void pmd_set(pmd_t *pmdp, pte_t *ptep)
 
 /* Don't use virt_to_pfn for macros below: could cause truncations for PAE40*/
 #define pte_pfn(pte)		(pte_val(pte) >> PAGE_SHIFT)
+#if CONFIG_HIGHMEM_PGDS_SHIFT
+#define __pte_index(addr)	(((addr) >= VMALLOC_END) ?		       \
+				(((addr) >> PAGE_SHIFT) & (PTRS_HMEM_PTE - 1)) \
+				:					       \
+				(((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)))
+#else
 #define __pte_index(addr)	(((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
+#endif
 
 /*
  * pte_offset gets a @ptr to PMD entry (PGD in our 2-tier paging system)
diff --git a/arch/arc/include/asm/processor.h b/arch/arc/include/asm/processor.h
index 6e1242d..fd7bdfa 100644
--- a/arch/arc/include/asm/processor.h
+++ b/arch/arc/include/asm/processor.h
@@ -121,8 +121,9 @@ extern void start_thread(struct pt_regs * regs, unsigned long pc,
 
 #define VMALLOC_START	(PAGE_OFFSET - (CONFIG_ARC_KVADDR_SIZE << 20))
 
-/* 1 PGDIR_SIZE each for fixmap/pkmap, 2 PGDIR_SIZE gutter (see asm/highmem.h) */
-#define VMALLOC_SIZE	((CONFIG_ARC_KVADDR_SIZE << 20) - PGDIR_SIZE * 4)
+/* 1 << CONFIG_HIGHMEM_PGDS_SHIFT PGDIR_SIZE each for fixmap/pkmap */
+#define VMALLOC_SIZE	((CONFIG_ARC_KVADDR_SIZE << 20) - \
+			  PGDIR_SIZE * _BITUL(CONFIG_HIGHMEM_PGDS_SHIFT) * 2)
 
 #define VMALLOC_END	(VMALLOC_START + VMALLOC_SIZE)
 
diff --git a/arch/arc/mm/fault.c b/arch/arc/mm/fault.c
index a0b7bd6..fd89c9a 100644
--- a/arch/arc/mm/fault.c
+++ b/arch/arc/mm/fault.c
@@ -17,6 +17,7 @@
 #include <linux/perf_event.h>
 #include <asm/pgalloc.h>
 #include <asm/mmu.h>
+#include <asm/highmem.h>
 
 /*
  * kernel virtual address is required to implement vmalloc/pkmap/fixmap
@@ -35,6 +36,13 @@ noinline static int handle_kernel_vaddr_fault(unsigned long address)
 	pud_t *pud, *pud_k;
 	pmd_t *pmd, *pmd_k;
 
+#if defined(CONFIG_HIGHMEM) && (CONFIG_HIGHMEM_PGDS_SHIFT)
+	if (address > FIXMAP_BASE && address < (FIXMAP_BASE + FIXMAP_SIZE))
+		address = FIXMAP_BASE;
+	else if (address > PKMAP_BASE && address < (PKMAP_BASE + PKMAP_SIZE))
+		address = PKMAP_BASE;
+#endif
+
 	pgd = pgd_offset_fast(current->active_mm, address);
 	pgd_k = pgd_offset_k(address);
 
diff --git a/arch/arc/mm/highmem.c b/arch/arc/mm/highmem.c
index 77ff64a..1d4804d 100644
--- a/arch/arc/mm/highmem.c
+++ b/arch/arc/mm/highmem.c
@@ -112,7 +112,8 @@ void __kunmap_atomic(void *kv)
 }
 EXPORT_SYMBOL(__kunmap_atomic);
 
-static noinline pte_t * __init alloc_kmap_pgtable(unsigned long kvaddr)
+static noinline pte_t * __init alloc_kmap_pgtable(unsigned long kvaddr,
+						  unsigned long pgnum)
 {
 	pgd_t *pgd_k;
 	pud_t *pud_k;
@@ -123,19 +124,24 @@ void __kunmap_atomic(void *kv)
 	pud_k = pud_offset(pgd_k, kvaddr);
 	pmd_k = pmd_offset(pud_k, kvaddr);
 
-	pte_k = (pte_t *)alloc_bootmem_low_pages(PAGE_SIZE);
+	pte_k = (pte_t *)alloc_bootmem_low_pages(pgnum * PAGE_SIZE);
 	pmd_populate_kernel(&init_mm, pmd_k, pte_k);
 	return pte_k;
 }
 
 void __init kmap_init(void)
 {
+	unsigned int pgnum;
+
 	/* Due to recursive include hell, we can't do this in processor.h */
 	BUILD_BUG_ON(PAGE_OFFSET < (VMALLOC_END + FIXMAP_SIZE + PKMAP_SIZE));
 
 	BUILD_BUG_ON(KM_TYPE_NR > PTRS_PER_PTE);
-	pkmap_page_table = alloc_kmap_pgtable(PKMAP_BASE);
+	pgnum = DIV_ROUND_UP(PKMAP_SIZE, PAGE_SIZE * PTRS_PER_PTE);
+	pkmap_page_table = alloc_kmap_pgtable(PKMAP_BASE, pgnum);
 
-	BUILD_BUG_ON(LAST_PKMAP > PTRS_PER_PTE);
-	fixmap_page_table = alloc_kmap_pgtable(FIXMAP_BASE);
+	BUILD_BUG_ON(LAST_PKMAP > (PTRS_PER_PTE *
+					_BITUL(CONFIG_HIGHMEM_PGDS_SHIFT)));
+	pgnum = DIV_ROUND_UP(FIXMAP_SIZE, PAGE_SIZE * PTRS_PER_PTE);
+	fixmap_page_table = alloc_kmap_pgtable(FIXMAP_BASE, pgnum);
 }
diff --git a/arch/arc/mm/tlbex.S b/arch/arc/mm/tlbex.S
index 0e1e47a..e21aecc 100644
--- a/arch/arc/mm/tlbex.S
+++ b/arch/arc/mm/tlbex.S
@@ -43,6 +43,7 @@
 #include <asm/cache.h>
 #include <asm/processor.h>
 #include <asm/tlb-mmu1.h>
+#include <asm/highmem.h>
 
 #ifdef CONFIG_ISA_ARCOMPACT
 ;-----------------------------------------------------------------
@@ -204,6 +205,12 @@ ex_saved_reg1:
 	ld  r1, [r1, MM_PGD]
 #endif
 
+#if defined(CONFIG_HIGHMEM) && defined(CONFIG_HIGHMEM_PGDS_SHIFT)
+	; handle pkmap/fixmap with more then on pte table
+	cmp_s   r2, VMALLOC_END
+	b.hs    4f
+#endif
+
 	lsr     r0, r2, PGDIR_SHIFT     ; Bits for indexing into PGD
 	ld.as   r3, [r1, r0]            ; PGD entry corresp to faulting addr
 	tst	r3, r3
@@ -237,6 +244,30 @@ ex_saved_reg1:
 
 2:
 
+#if defined(CONFIG_HIGHMEM) && defined(CONFIG_HIGHMEM_PGDS_SHIFT)
+	b       6f
+
+4:
+	lsr     r0, r2, PGDIR_SHIFT         ; Bits for indexing into KMAP_PGD
+	and     r0, r0, ~(_BITUL(CONFIG_HIGHMEM_PGDS_SHIFT) - 1)
+	ld.as   r1, [r1, r0]                ; PGD entry corresp to faulting addr
+	tst     r1, r1
+	bz      do_slow_path_pf             ; if no Page Table, do page fault
+	and     r1, r1, PAGE_MASK
+
+	cmp_s   r2, PKMAP_BASE
+	mov.hs  r0, ( PKMAP_BASE >> PAGE_SHIFT )
+	b.hs    5f
+	mov     r0, ( FIXMAP_BASE >> PAGE_SHIFT )
+
+5:
+	lsr     r3, r2, PAGE_SHIFT
+	sub     r0, r3, r0
+	asl     r0, r0, PTE_SIZE_LOG
+	ld.aw   r0, [r1, r0]
+6:
+#endif
+
 .endm
 
 ;-----------------------------------------------------------------
-- 
1.7.1

[PATCH v3 06/11] ARC: [NUMA] added CONFIG_NUMA for plat-eznps

[Noam Camus]

From: Noam Camus <noamca@mellanox.com>

This is needed for NPS400 where high memory is assigned to node1
where the associated addresses are lower than node0.
This use case is not typical and just using discontigmem is not enough
since nodes assumed to have increasing address range.
i.e. address range of node0 assumed to be lower than node1.

Signed-off-by: Noam Camus <noamca@mellanox.com>
---
 arch/arc/Kconfig                |    9 +++++++++
 arch/arc/include/asm/topology.h |    6 ++++++
 arch/arc/kernel/setup.c         |    3 +++
 arch/arc/mm/init.c              |    6 ++++++
 4 files changed, 24 insertions(+), 0 deletions(-)

diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
index 982bd18..18c37de 100644
--- a/arch/arc/Kconfig
+++ b/arch/arc/Kconfig
@@ -378,6 +378,15 @@ config ARC_HUGEPAGE_16M
 
 endchoice
 
+config NUMA
+	bool "NUMA Memory Allocation and Scheduler Support"
+	depends on SMP && DISCONTIGMEM
+	default y if ARC_PLAT_EZNPS
+	---help---
+	  NUMA memory allocation is required for NPS400 processors.
+	  The reason is that node1 in NPS400 is assigned to lower
+	  addresses than node0, which is not typical scenario.
+
 config NODES_SHIFT
 	int "Maximum NUMA Nodes (as a power of 2)"
 	default "0" if !DISCONTIGMEM
diff --git a/arch/arc/include/asm/topology.h b/arch/arc/include/asm/topology.h
index a9be3f8..dfbc2ab 100644
--- a/arch/arc/include/asm/topology.h
+++ b/arch/arc/include/asm/topology.h
@@ -1,6 +1,12 @@
 #ifndef _ASM_ARC_TOPOLOGY_H
 #define _ASM_ARC_TOPOLOGY_H
 
+#ifdef CONFIG_NUMA
+#define cpu_to_node(cpu)	((void)(cpu), 0)
+#define parent_node(node)	(node)
+#define cpumask_of_node(node)	((void)node, cpu_online_mask)
+#endif
+
 #ifdef CONFIG_NPS_CPU_TOPOLOGY
 
 #include <linux/cpumask.h>
diff --git a/arch/arc/kernel/setup.c b/arch/arc/kernel/setup.c
index 379ebda..3d1509b 100644
--- a/arch/arc/kernel/setup.c
+++ b/arch/arc/kernel/setup.c
@@ -577,6 +577,9 @@ static int __init topology_init(void)
 {
 	int cpu;
 
+	for_each_online_node(cpu)
+		register_one_node(cpu);
+
 	for_each_present_cpu(cpu)
 		register_cpu(&per_cpu(cpu_topo_info, cpu), cpu);
 
diff --git a/arch/arc/mm/init.c b/arch/arc/mm/init.c
index 8c9415e..f9f80d9 100644
--- a/arch/arc/mm/init.c
+++ b/arch/arc/mm/init.c
@@ -113,6 +113,10 @@ void __init setup_arch_memory(void)
 	init_mm.end_data = (unsigned long)_edata;
 	init_mm.brk = (unsigned long)_end;
 
+	node_set_online(0);
+	node_set_state(0, N_MEMORY);
+	node_set_state(0, N_NORMAL_MEMORY);
+
 	/* first page of system - kernel .vector starts here */
 	min_low_pfn = ARCH_PFN_OFFSET;
 
@@ -182,6 +186,8 @@ void __init setup_arch_memory(void)
 	 * populated with normal memory zone while node 1 only has highmem
 	 */
 	node_set_online(1);
+	node_set_state(1, N_MEMORY);
+	node_set_state(1, N_HIGH_MEMORY);
 
 	min_high_pfn = PFN_DOWN(high_mem_start);
 	max_high_pfn = PFN_DOWN(high_mem_start + high_mem_sz);
-- 
1.7.1

[PATCH v3 07/11] ARC: [plat-eznps] new command line argument for HW scheduler at MTM

[Noam Camus]

From: Noam Camus <noamca@mellanox.com>

We add ability for all cores at NPS SoC to control the number of cycles
HW thread can execute before it is replace with another eligible
HW thread within the same core. The replacement is done by the
HW scheduler.

Signed-off-by: Noam Camus <noamca@mellanox.com>
---
 Documentation/admin-guide/kernel-parameters.txt |    9 ++++
 arch/arc/plat-eznps/mtm.c                       |   46 ++++++++++++++++++++++-
 2 files changed, 53 insertions(+), 2 deletions(-)

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 15f79c2..5b551f7 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -2693,6 +2693,15 @@
 			If the dependencies are under your control, you can
 			turn on cpu0_hotplug.
 
+	nps_mtm_hs_ctr= [KNL,ARC]
+			This parameter sets the maximum duration, in
+			cycles, each HW thread of the CTOP can run
+			without interruptions, before HW switches it.
+			The actual maximum duration is 16 times this
+			parameter's value.
+			Format: integer between 1 and 255
+			Default: 255
+
 	nptcg=		[IA-64] Override max number of concurrent global TLB
 			purges which is reported from either PAL_VM_SUMMARY or
 			SAL PALO.
diff --git a/arch/arc/plat-eznps/mtm.c b/arch/arc/plat-eznps/mtm.c
index dcbf8f6..9c78ad6 100644
--- a/arch/arc/plat-eznps/mtm.c
+++ b/arch/arc/plat-eznps/mtm.c
@@ -21,10 +21,13 @@
 #include <plat/mtm.h>
 #include <plat/smp.h>
 
-#define MT_CTRL_HS_CNT		0xFF
+#define MT_HS_CNT_MIN		0x01
+#define MT_HS_CNT_MAX		0xFF
 #define MT_CTRL_ST_CNT		0xF
 #define NPS_NUM_HW_THREADS	0x10
 
+static int mtm_hs_ctr = MT_HS_CNT_MAX;
+
 #ifdef CONFIG_EZNPS_MEM_ERROR_ALIGN
 int do_memory_error(unsigned long address, struct pt_regs *regs)
 {
@@ -127,7 +130,7 @@ void mtm_enable_core(unsigned int cpu)
 	/* Enable HW schedule, stall counter, mtm */
 	mt_ctrl.value = 0;
 	mt_ctrl.hsen = 1;
-	mt_ctrl.hs_cnt = MT_CTRL_HS_CNT;
+	mt_ctrl.hs_cnt = mtm_hs_ctr;
 	mt_ctrl.mten = 1;
 	write_aux_reg(CTOP_AUX_MT_CTRL, mt_ctrl.value);
 
@@ -138,3 +141,42 @@ void mtm_enable_core(unsigned int cpu)
 	 */
 	cpu_relax();
 }
+
+/* Handle an out of bounds mtm hs counter value */
+static void __init handle_mtm_hs_ctr_out_of_bounds_error(uint8_t val)
+{
+	pr_err("** The value must be in range [%d,%d] (inclusive)\n",
+		MT_HS_CNT_MIN, MT_HS_CNT_MAX);
+
+	mtm_hs_ctr = val;
+}
+
+/* Verify and set the value of the mtm hs counter */
+static int __init set_mtm_hs_ctr(char *ctr_str)
+{
+	int ret;
+	long hs_ctr;
+
+	ret = kstrtol(ctr_str, 0, &hs_ctr);
+	if (ret) {
+		pr_err("** Out of range mtm_hs_ctr, using default value %d\n",
+			MT_HS_CNT_MAX);
+		mtm_hs_ctr = MT_HS_CNT_MAX;
+		return -EINVAL;
+	}
+
+	if (hs_ctr > MT_HS_CNT_MAX) {
+		handle_mtm_hs_ctr_out_of_bounds_error(MT_HS_CNT_MAX);
+		return -EDOM;
+	}
+
+	if (hs_ctr < MT_HS_CNT_MIN) {
+		handle_mtm_hs_ctr_out_of_bounds_error(MT_HS_CNT_MIN);
+		return -EDOM;
+	}
+
+	mtm_hs_ctr = hs_ctr;
+
+	return 0;
+}
+early_param("nps_mtm_hs_ctr", set_mtm_hs_ctr);
-- 
1.7.1

[PATCH v3 08/11] ARC: [plat-eznps] Update the init sequence of aux regs per cpu.

[Noam Camus]

From: Liav Rehana <liavr@mellanox.com>

This commit add new configuration that enables us to distinguish
between building the kernel for platforms that have a different set
of auxiliary registers for each cpu and platforms that have a shared
set of auxiliary registers across every thread in each core.
On platforms that implement a different set of auxiliary registers
disabling this configuration insures that we initialize registers on
every cpu and not just for the first thread of the core.
Example for non shared registers is working with EZsim (non silicon)

Signed-off-by: Liav Rehana <liavr@mellanox.com>
Signed-off-by: Noam Camus <noamca@mellanox.com>
---
 arch/arc/plat-eznps/Kconfig |   11 +++++++++++
 arch/arc/plat-eznps/entry.S |    2 +-
 2 files changed, 12 insertions(+), 1 deletions(-)

diff --git a/arch/arc/plat-eznps/Kconfig b/arch/arc/plat-eznps/Kconfig
index b36afb1..e151e20 100644
--- a/arch/arc/plat-eznps/Kconfig
+++ b/arch/arc/plat-eznps/Kconfig
@@ -43,3 +43,14 @@ config EZNPS_MEM_ERROR_ALIGN
 	  simulator platform for NPS, is handled as a Level 2 interrupt
 	  (just a stock ARC700) which is recoverable. This option makes
 	  simulator behave like hardware.
+
+config EZNPS_SHARED_AUX_REGS
+	bool "ARC-EZchip Shared Auxiliary Registers Per Core"
+	depends on ARC_PLAT_EZNPS
+	default y
+	help
+	  On the real chip of the NPS, auxiliary registers are shared between
+	  all the cpus of the core, whereas on simulator platform for NPS,
+	  each cpu has a different set of auxiliary registers. Configuration
+	  should be unset if auxiliary registers are not shared between the cpus
+	  of the core, so there will be a need to initialize them per cpu.
diff --git a/arch/arc/plat-eznps/entry.S b/arch/arc/plat-eznps/entry.S
index 328261c..091c92c 100644
--- a/arch/arc/plat-eznps/entry.S
+++ b/arch/arc/plat-eznps/entry.S
@@ -27,7 +27,7 @@
 	.align 1024	; HW requierment for restart first PC
 
 ENTRY(res_service)
-#ifdef CONFIG_EZNPS_MTM_EXT
+#if defined(CONFIG_EZNPS_MTM_EXT) && defined(CONFIG_EZNPS_SHARED_AUX_REGS)
 	; There is no work for HW thread id != 0
 	lr	r3, [CTOP_AUX_THREAD_ID]
 	cmp	r3, 0
-- 
1.7.1

[PATCH v3 09/11] ARC: [plat-eznps] Save/Restore extra auxiliary registers

[Noam Camus]

From: Noam Camus <noamc@ezchip.com>

thread_struct got new field for data plane of eznps platform.
This field got place for data plane auxiliary registers and for
any extra registers that might be changed in kernel code.

We save EFLAGS, and GPA1 auxiliary registers since they may be
changed by the new task while using atomic operations e.g. cmpxchg.

Signed-off-by: Noam Camus <noamc@ezchip.com>
---
 arch/arc/include/asm/arcregs.h   |    7 +++++++
 arch/arc/include/asm/processor.h |    3 +++
 arch/arc/include/asm/switch_to.h |   11 +++++++++++
 arch/arc/plat-eznps/Makefile     |    2 +-
 arch/arc/plat-eznps/ctop.c       |   33 +++++++++++++++++++++++++++++++++
 5 files changed, 55 insertions(+), 1 deletions(-)
 create mode 100644 arch/arc/plat-eznps/ctop.c

diff --git a/arch/arc/include/asm/arcregs.h b/arch/arc/include/asm/arcregs.h
index ba8e802..9437d42 100644
--- a/arch/arc/include/asm/arcregs.h
+++ b/arch/arc/include/asm/arcregs.h
@@ -123,6 +123,13 @@
 #define PAGES_TO_MB(n_pages)	(PAGES_TO_KB(n_pages) >> 10)
 
 
+#ifdef CONFIG_ARC_PLAT_EZNPS
+struct eznps_dp {
+	unsigned int eflags;
+	unsigned int gpa1;
+};
+#endif
+
 /*
  ***************************************************************
  * Build Configuration Registers, with encoded hardware config
diff --git a/arch/arc/include/asm/processor.h b/arch/arc/include/asm/processor.h
index fd7bdfa..130bb55 100644
--- a/arch/arc/include/asm/processor.h
+++ b/arch/arc/include/asm/processor.h
@@ -38,6 +38,9 @@ struct thread_struct {
 #ifdef CONFIG_ARC_FPU_SAVE_RESTORE
 	struct arc_fpu fpu;
 #endif
+#ifdef CONFIG_ARC_PLAT_EZNPS
+	struct eznps_dp dp;
+#endif
 };
 
 #define INIT_THREAD  {                          \
diff --git a/arch/arc/include/asm/switch_to.h b/arch/arc/include/asm/switch_to.h
index 1b171ab..4c53080 100644
--- a/arch/arc/include/asm/switch_to.h
+++ b/arch/arc/include/asm/switch_to.h
@@ -26,13 +26,24 @@
 
 #endif /* !CONFIG_ARC_FPU_SAVE_RESTORE */
 
+#ifdef CONFIG_ARC_PLAT_EZNPS
+extern void dp_save_restore(struct task_struct *p, struct task_struct *n);
+#define ARC_DP_PREV(p, n)      dp_save_restore(p, n)
+#define ARC_DP_NEXT(t)
+#else
+#define ARC_DP_PREV(p, n)
+#define ARC_DP_NEXT(n)
+#endif /* !CONFIG_ARC_PLAT_EZNPS */
+
 struct task_struct *__switch_to(struct task_struct *p, struct task_struct *n);
 
 #define switch_to(prev, next, last)	\
 do {					\
+	ARC_DP_PREV(prev, next);	\
 	ARC_FPU_PREV(prev, next);	\
 	last = __switch_to(prev, next);\
 	ARC_FPU_NEXT(next);		\
+	ARC_DP_NEXT(next);		\
 	mb();				\
 } while (0)
 
diff --git a/arch/arc/plat-eznps/Makefile b/arch/arc/plat-eznps/Makefile
index 21091b1..8d43717 100644
--- a/arch/arc/plat-eznps/Makefile
+++ b/arch/arc/plat-eznps/Makefile
@@ -2,6 +2,6 @@
 # Makefile for the linux kernel.
 #
 
-obj-y := entry.o platform.o
+obj-y := entry.o platform.o ctop.o
 obj-$(CONFIG_SMP) += smp.o
 obj-$(CONFIG_EZNPS_MTM_EXT) += mtm.o
diff --git a/arch/arc/plat-eznps/ctop.c b/arch/arc/plat-eznps/ctop.c
new file mode 100644
index 0000000..8b13a08
--- /dev/null
+++ b/arch/arc/plat-eznps/ctop.c
@@ -0,0 +1,33 @@
+/*
+ * Copyright(c) 2015 EZchip Technologies.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * The full GNU General Public License is included in this distribution in
+ * the file called "COPYING".
+ */
+
+#include <linux/sched.h>
+#include <asm/arcregs.h>
+#include <plat/ctop.h>
+
+void dp_save_restore(struct task_struct *prev, struct task_struct *next)
+{
+	struct eznps_dp *prev_task_dp = &prev->thread.dp;
+	struct eznps_dp *next_task_dp = &next->thread.dp;
+
+	/* Here we save all Data Plane related auxiliary registers */
+	prev_task_dp->eflags = read_aux_reg(CTOP_AUX_EFLAGS);
+	write_aux_reg(CTOP_AUX_EFLAGS, next_task_dp->eflags);
+
+	prev_task_dp->gpa1 = read_aux_reg(CTOP_AUX_GPA1);
+	write_aux_reg(CTOP_AUX_GPA1, next_task_dp->gpa1);
+}
+
-- 
1.7.1

[PATCH v3 10/11] ARC: [plat-eznps] handle dedicated AUX registers

[Noam Camus]

From: Liav Rehana <liavr@mellanox.com>

Preserve eflags and gpa1 auxiliaries during exception
Registers used by compare exchange instructions.
GPA1 is used for compare value, and EFLAGS got bit reflects
atomic operation response.

EFLAGS is zeroed for each new user task so it won't get its
parent value.

Signed-off-by: Noam Camus <noamc@ezchip.com>
---
 arch/arc/include/asm/entry-compact.h |   24 ++++++++++++++++++++++++
 arch/arc/include/asm/ptrace.h        |    5 +++++
 arch/arc/kernel/process.c            |    4 ++++
 3 files changed, 33 insertions(+), 0 deletions(-)

diff --git a/arch/arc/include/asm/entry-compact.h b/arch/arc/include/asm/entry-compact.h
index 14c310f..9e4458a 100644
--- a/arch/arc/include/asm/entry-compact.h
+++ b/arch/arc/include/asm/entry-compact.h
@@ -192,6 +192,12 @@
 	PUSHAX	lp_start
 	PUSHAX	erbta
 
+#ifdef CONFIG_ARC_PLAT_EZNPS
+	.word CTOP_INST_SCHD_RW
+	PUSHAX  CTOP_AUX_GPA1
+	PUSHAX  CTOP_AUX_EFLAGS
+#endif
+`
 	lr	r9, [ecr]
 	st      r9, [sp, PT_event]    /* EV_Trap expects r9 to have ECR */
 .endm
@@ -208,6 +214,12 @@
  * by hardware and that is not good.
  *-------------------------------------------------------------*/
 .macro EXCEPTION_EPILOGUE
+#ifdef CONFIG_ARC_PLAT_EZNPS
+	.word CTOP_INST_SCHD_RW
+	POPAX   CTOP_AUX_EFLAGS
+	POPAX   CTOP_AUX_GPA1
+#endif
+
 	POPAX	erbta
 	POPAX	lp_start
 	POPAX	lp_end
@@ -265,6 +277,12 @@
 	PUSHAX	lp_end
 	PUSHAX	lp_start
 	PUSHAX	bta_l\LVL\()
+
+#ifdef CONFIG_ARC_PLAT_EZNPS
+	.word CTOP_INST_SCHD_RW
+	PUSHAX  CTOP_AUX_GPA1
+	PUSHAX  CTOP_AUX_EFLAGS
+#endif
 .endm
 
 /*--------------------------------------------------------------
@@ -277,6 +295,12 @@
  * by hardware and that is not good.
  *-------------------------------------------------------------*/
 .macro INTERRUPT_EPILOGUE  LVL
+#ifdef CONFIG_ARC_PLAT_EZNPS
+	.word CTOP_INST_SCHD_RW
+	POPAX   CTOP_AUX_EFLAGS
+	POPAX   CTOP_AUX_GPA1
+#endif
+
 	POPAX	bta_l\LVL\()
 	POPAX	lp_start
 	POPAX	lp_end
diff --git a/arch/arc/include/asm/ptrace.h b/arch/arc/include/asm/ptrace.h
index 5297faa..5a8cb22 100644
--- a/arch/arc/include/asm/ptrace.h
+++ b/arch/arc/include/asm/ptrace.h
@@ -19,6 +19,11 @@
 #ifdef CONFIG_ISA_ARCOMPACT
 struct pt_regs {
 
+#ifdef CONFIG_ARC_PLAT_EZNPS
+	unsigned long eflags;	/* Extended FLAGS */
+	unsigned long gpa1;	/* General Purpose Aux */
+#endif
+
 	/* Real registers */
 	unsigned long bta;	/* bta_l1, bta_l2, erbta */
 
diff --git a/arch/arc/kernel/process.c b/arch/arc/kernel/process.c
index 5c631a1..5ac3b54 100644
--- a/arch/arc/kernel/process.c
+++ b/arch/arc/kernel/process.c
@@ -234,6 +234,10 @@ void start_thread(struct pt_regs * regs, unsigned long pc, unsigned long usp)
 	 */
 	regs->status32 = STATUS_U_MASK | STATUS_L_MASK | ISA_INIT_STATUS_BITS;
 
+#ifdef CONFIG_EZNPS_MTM_EXT
+	regs->eflags = 0;
+#endif
+
 	/* bogus seed values for debugging */
 	regs->lp_start = 0x10;
 	regs->lp_end = 0x80;
-- 
1.7.1

[PATCH v3 11/11] ARC: [plat-eznps] avoid toggling of DPC register

[Noam Camus]

From: Elad Kanfi <eladkan@mellanox.com>

HW bug description: in case of HW thread context switch
the dpc configuration of the exiting thread is dragged
one cycle into the next thread.
In order to avoid the consequences of this bug, the DPC register
is set to an initial value, and not changed afterwards.

Signed-off-by: Elad Kanfi <eladkan@mellanox.com>
Signed-off-by: Noam Camus <noamca@mellanox.com>
---
 arch/arc/plat-eznps/include/plat/ctop.h |    1 +
 arch/arc/plat-eznps/mtm.c               |   12 ++++++++++++
 2 files changed, 13 insertions(+), 0 deletions(-)

diff --git a/arch/arc/plat-eznps/include/plat/ctop.h b/arch/arc/plat-eznps/include/plat/ctop.h
index 7729d3d..0c7d110 100644
--- a/arch/arc/plat-eznps/include/plat/ctop.h
+++ b/arch/arc/plat-eznps/include/plat/ctop.h
@@ -39,6 +39,7 @@
 #define CTOP_AUX_LOGIC_CORE_ID			(CTOP_AUX_BASE + 0x018)
 #define CTOP_AUX_MT_CTRL			(CTOP_AUX_BASE + 0x020)
 #define CTOP_AUX_HW_COMPLY			(CTOP_AUX_BASE + 0x024)
+#define CTOP_AUX_DPC				(CTOP_AUX_BASE + 0x02C)
 #define CTOP_AUX_LPC				(CTOP_AUX_BASE + 0x030)
 #define CTOP_AUX_EFLAGS				(CTOP_AUX_BASE + 0x080)
 #define CTOP_AUX_IACK				(CTOP_AUX_BASE + 0x088)
diff --git a/arch/arc/plat-eznps/mtm.c b/arch/arc/plat-eznps/mtm.c
index 9c78ad6..909bbd4 100644
--- a/arch/arc/plat-eznps/mtm.c
+++ b/arch/arc/plat-eznps/mtm.c
@@ -110,6 +110,18 @@ void mtm_enable_core(unsigned int cpu)
 	int i;
 	struct nps_host_reg_aux_mt_ctrl mt_ctrl;
 	struct nps_host_reg_mtm_cfg mtm_cfg;
+	struct nps_host_reg_aux_dpc dpc;
+
+	/*
+	 * Initializing dpc register in each CPU.
+	 * Overwriting the init value of the DPC
+	 * register so that CMEM and FMT virtual address
+	 * spaces are accessible, and Data Plane HW
+	 * facilities are enabled.
+	 */
+	dpc.ien = 1;
+	dpc.men = 1;
+	write_aux_reg(CTOP_AUX_DPC, dpc.value);
 
 	if (NPS_CPU_TO_THREAD_NUM(cpu) != 0)
 		return;
-- 
1.7.1

Re: [PATCH v3 07/11] ARC: [plat-eznps] new command line argument for HW scheduler at MTM

[Vineet Gupta]

On 06/15/2017 01:43 AM, Noam Camus wrote:
> From: Noam Camus <noamca@mellanox.com>
> 
> We add ability for all cores at NPS SoC to control the number of cycles
> HW thread can execute before it is replace with another eligible
> HW thread within the same core. The replacement is done by the
> HW scheduler.
> 
> Signed-off-by: Noam Camus <noamca@mellanox.com>
> ---
>   Documentation/admin-guide/kernel-parameters.txt |    9 ++++
>   arch/arc/plat-eznps/mtm.c                       |   46 ++++++++++++++++++++++-
>   2 files changed, 53 insertions(+), 2 deletions(-)
> 
> diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
> index 15f79c2..5b551f7 100644
> --- a/Documentation/admin-guide/kernel-parameters.txt
> +++ b/Documentation/admin-guide/kernel-parameters.txt
> @@ -2693,6 +2693,15 @@
>   			If the dependencies are under your control, you can
>   			turn on cpu0_hotplug.
>   
> +	nps_mtm_hs_ctr= [KNL,ARC]
> +			This parameter sets the maximum duration, in
> +			cycles, each HW thread of the CTOP can run
> +			without interruptions, before HW switches it.
> +			The actual maximum duration is 16 times this
> +			parameter's value.
> +			Format: integer between 1 and 255
> +			Default: 255
> +
>   	nptcg=		[IA-64] Override max number of concurrent global TLB
>   			purges which is reported from either PAL_VM_SUMMARY or
>   			SAL PALO.
> diff --git a/arch/arc/plat-eznps/mtm.c b/arch/arc/plat-eznps/mtm.c
> index dcbf8f6..9c78ad6 100644
> --- a/arch/arc/plat-eznps/mtm.c
> +++ b/arch/arc/plat-eznps/mtm.c
> @@ -21,10 +21,13 @@
>   #include <plat/mtm.h>
>   #include <plat/smp.h>
>   
> -#define MT_CTRL_HS_CNT		0xFF
> +#define MT_HS_CNT_MIN		0x01
> +#define MT_HS_CNT_MAX		0xFF
>   #define MT_CTRL_ST_CNT		0xF
>   #define NPS_NUM_HW_THREADS	0x10
>   
> +static int mtm_hs_ctr = MT_HS_CNT_MAX;
> +
>   #ifdef CONFIG_EZNPS_MEM_ERROR_ALIGN
>   int do_memory_error(unsigned long address, struct pt_regs *regs)
>   {
> @@ -127,7 +130,7 @@ void mtm_enable_core(unsigned int cpu)
>   	/* Enable HW schedule, stall counter, mtm */
>   	mt_ctrl.value = 0;
>   	mt_ctrl.hsen = 1;
> -	mt_ctrl.hs_cnt = MT_CTRL_HS_CNT;
> +	mt_ctrl.hs_cnt = mtm_hs_ctr;
>   	mt_ctrl.mten = 1;
>   	write_aux_reg(CTOP_AUX_MT_CTRL, mt_ctrl.value);
>   
> @@ -138,3 +141,42 @@ void mtm_enable_core(unsigned int cpu)
>   	 */
>   	cpu_relax();
>   }
> +
> +/* Handle an out of bounds mtm hs counter value */
> +static void __init handle_mtm_hs_ctr_out_of_bounds_error(uint8_t val)
> +{
> +	pr_err("** The value must be in range [%d,%d] (inclusive)\n",
> +		MT_HS_CNT_MIN, MT_HS_CNT_MAX);
> +
> +	mtm_hs_ctr = val;


This error handling doesn't make sense to me - if the value is not in range, why 
bother setting it at all. I'll fix it up locally.


> +}
> +
> +/* Verify and set the value of the mtm hs counter */
> +static int __init set_mtm_hs_ctr(char *ctr_str)
> +{
> +	int ret;
> +	long hs_ctr;
> +
> +	ret = kstrtol(ctr_str, 0, &hs_ctr);
> +	if (ret) {
> +		pr_err("** Out of range mtm_hs_ctr, using default value %d\n",
> +			MT_HS_CNT_MAX);
> +		mtm_hs_ctr = MT_HS_CNT_MAX;
> +		return -EINVAL;
> +	}
> +
> +	if (hs_ctr > MT_HS_CNT_MAX) {
> +		handle_mtm_hs_ctr_out_of_bounds_error(MT_HS_CNT_MAX);
> +		return -EDOM;
> +	}
> +
> +	if (hs_ctr < MT_HS_CNT_MIN) {
> +		handle_mtm_hs_ctr_out_of_bounds_error(MT_HS_CNT_MIN);
> +		return -EDOM;
> +	}
> +
> +	mtm_hs_ctr = hs_ctr;
> +
> +	return 0;
> +}
> +early_param("nps_mtm_hs_ctr", set_mtm_hs_ctr);
> 

RE: [PATCH v3 07/11] ARC: [plat-eznps] new command line argument for HW scheduler at MTM

[Noam Camus]

>From: Vineet Gupta [mailto:Vineet.Gupta1@synopsys.com] 
>Sent: Monday, August 21, 2017 20:04 PM
....
>> +
>> +/* Handle an out of bounds mtm hs counter value */ static void __init 
>> +handle_mtm_hs_ctr_out_of_bounds_error(uint8_t val) {
>> +	pr_err("** The value must be in range [%d,%d] (inclusive)\n",
>> +		MT_HS_CNT_MIN, MT_HS_CNT_MAX);
>> +
>> +	mtm_hs_ctr = val;


>This error handling doesn't make sense to me - if the value is not in range, why bother setting it at all. I'll fix it up locally.
Just look what we provide handle_mtm_hs_ctr_out_of_bounds_error() as parameter and it will be sensible to you :)

Noam 

Re: [PATCH v3 03/11] ARC: Allow irq threading

[Vineet Gupta]

+CC Peter, Tglx, Steven

On 06/15/2017 01:43 AM, Noam Camus wrote:
> From: Noam Camus <noamc@ezchip.com>
> 
> Working with NPS400 we noticed that there is a possibility of L1
> interrupt nesting that may run out kernel stack.
> The scenario include serving invoke_softirqs() from irq_exit()
> and once local_irq_enable() called can hit another one before we
> managed to restore last one and pop some place from kernel stack.
> 
> Serving softirqs at dedicated kernel thread may mitigate this.
> We see that many architectures, including x86, behave like this.
> 
> Note 1: All interrupts which must be non threaded
> should be marked IRQF_NO_THREAD.
> Note 2: using kernel param "threadirqs" is needed to actually
> turn this on. This configuration is only a preperation.
> 
> Signed-off-by: Noam Camus <noamc@ezchip.com>
> ---
>   arch/arc/Kconfig |    1 +
>   1 files changed, 1 insertions(+), 0 deletions(-)
> 
> diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
> index a545969..f464f97 100644
> --- a/arch/arc/Kconfig
> +++ b/arch/arc/Kconfig
> @@ -33,6 +33,7 @@ config ARC
>   	select HAVE_OPROFILE
>   	select HAVE_PERF_EVENTS
>   	select HANDLE_DOMAIN_IRQ
> +	select IRQ_FORCED_THREADING
>   	select IRQ_DOMAIN
>   	select MODULES_USE_ELF_RELA
>   	select NO_BOOTMEM> 

As Noam notes above and looking at work needed in other arches prior to switching 
to this: we need mark the low level ints as NO_THREAD.

ARC ipi, timer, perf interrupts happen to use request_percpu_irq() which doesn't 
take flags and doesn't seem to force NO_THREAD internally either. Does that mean 
we first need to convert all of these sites to __request_percpu_irq(.. NO_THREAD 
...) or is there a better way of doing this !

Thx,
-Vineet

Re: [PATCH v3 03/11] ARC: Allow irq threading

[Thomas Gleixner]

On Fri, 25 Aug 2017, Vineet Gupta wrote:
> On 06/15/2017 01:43 AM, Noam Camus wrote:
> > From: Noam Camus <noamc@ezchip.com>
> > 
> > Working with NPS400 we noticed that there is a possibility of L1
> > interrupt nesting that may run out kernel stack.
> > The scenario include serving invoke_softirqs() from irq_exit()
> > and once local_irq_enable() called can hit another one before we
> > managed to restore last one and pop some place from kernel stack.
> > 
> > Serving softirqs at dedicated kernel thread may mitigate this.
> > We see that many architectures, including x86, behave like this.

Well, no. x86 supports that, but that does not mean many user add it to the
command line.

> > Note 1: All interrupts which must be non threaded
> > should be marked IRQF_NO_THREAD.
> > Note 2: using kernel param "threadirqs" is needed to actually
> > turn this on. This configuration is only a preperation.
> > 
> > Signed-off-by: Noam Camus <noamc@ezchip.com>
> > ---
> >   arch/arc/Kconfig |    1 +
> >   1 files changed, 1 insertions(+), 0 deletions(-)
> > 
> > diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
> > index a545969..f464f97 100644
> > --- a/arch/arc/Kconfig
> > +++ b/arch/arc/Kconfig
> > @@ -33,6 +33,7 @@ config ARC
> >   	select HAVE_OPROFILE
> >   	select HAVE_PERF_EVENTS
> >   	select HANDLE_DOMAIN_IRQ
> > +	select IRQ_FORCED_THREADING
> >   	select IRQ_DOMAIN
> >   	select MODULES_USE_ELF_RELA
> >   	select NO_BOOTMEM> 
> 
> As Noam notes above and looking at work needed in other arches prior to
> switching to this: we need mark the low level ints as NO_THREAD.
> 
> ARC ipi, timer, perf interrupts happen to use request_percpu_irq() which
> doesn't take flags and doesn't seem to force NO_THREAD internally either. Does
> that mean we first need to convert all of these sites to
> __request_percpu_irq(.. NO_THREAD ...) or is there a better way of doing this
> !

PER CPU interrupts are excluded from force threading automatically.

Thanks,

	tglx

Re: [PATCH v3 03/11] ARC: Allow irq threading

[Thomas Gleixner]

On Fri, 25 Aug 2017, Thomas Gleixner wrote:

> On Fri, 25 Aug 2017, Vineet Gupta wrote:
> > On 06/15/2017 01:43 AM, Noam Camus wrote:
> > > From: Noam Camus <noamc@ezchip.com>
> > > 
> > > Working with NPS400 we noticed that there is a possibility of L1
> > > interrupt nesting that may run out kernel stack.
> > > The scenario include serving invoke_softirqs() from irq_exit()
> > > and once local_irq_enable() called can hit another one before we
> > > managed to restore last one and pop some place from kernel stack.
> > > 
> > > Serving softirqs at dedicated kernel thread may mitigate this.
> > > We see that many architectures, including x86, behave like this.
> 
> Well, no. x86 supports that, but that does not mean many user add it to the
> command line.

The real fix for that is to use dedicated irq and softirq stacks instead of
using the potentially deep thread stack for everything. That's what x86 and
others do unconditinally.

Thanks,

	tglx