Upgrade to 4.4.50-rt62

The current kernel is based on rt kernel v4.4.6-rt14. We will upgrade it
to 4.4.50-rt62.
The command to achieve it is:
a) Clone a git repo from
git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-stable-rt.git

b) Get the diff between this two changesets:
git diff 640eca2901f3435e616157b11379d3223a44b391
705619beeea1b0b48219a683fd1a901a86fdaf5e

where the two commits are:
[yjiang5@jnakajim-build linux-stable-rt]$ git show --oneline --name-only
640eca2901f3435e616157b11379d3223a44b391
640eca2901f3 v4.4.6-rt14
localversion-rt
[yjiang5@jnakajim-build linux-stable-rt]$ git show --oneline --name-only
705619beeea1b0b48219a683fd1a901a86fdaf5e
705619beeea1 Linux 4.4.50-rt62
localversion-rt

c) One patch has been backported thus revert the patch before applying.

 filterdiff -p1 -x scripts/package/Makefile
~/tmp/v4.4.6-rt14-4.4.50-rt62.diff  |patch -p1 --dry-run

Upstream status: backport

Change-Id: I244d57a32f6066e5a5b9915f9fbf99e7bbca6e01
Signed-off-by: Yunhong Jiang <yunhong.jiang@linux.intel.com>

17 files changed, 107 insertions, 74 deletions

diff --git a/kernel/arch/arc/Kconfig b/kernel/arch/arc/Kconfig
index 6312f6079..2d785f5a3 100644
--- a/kernel/arch/arc/Kconfig
+++ b/kernel/arch/arc/Kconfig
@@ -387,7 +387,7 @@ config ARC_HAS_LLSC
 
 config ARC_STAR_9000923308
 	bool "Workaround for llock/scond livelock"
-	default y
+	default n
 	depends on ISA_ARCV2 && SMP && ARC_HAS_LLSC
 
 config ARC_HAS_SWAPE
diff --git a/kernel/arch/arc/Makefile b/kernel/arch/arc/Makefile
index aeb190210..c05ea2b54 100644
--- a/kernel/arch/arc/Makefile
+++ b/kernel/arch/arc/Makefile
@@ -18,6 +18,20 @@ cflags-y	+= -fno-common -pipe -fno-builtin -D__linux__
 cflags-$(CONFIG_ISA_ARCOMPACT)	+= -mA7
 cflags-$(CONFIG_ISA_ARCV2)	+= -mcpu=archs
 
+is_700 = $(shell $(CC) -dM -E - < /dev/null | grep -q "ARC700" && echo 1 || echo 0)
+
+ifdef CONFIG_ISA_ARCOMPACT
+ifeq ($(is_700), 0)
+    $(error Toolchain not configured for ARCompact builds)
+endif
+endif
+
+ifdef CONFIG_ISA_ARCV2
+ifeq ($(is_700), 1)
+    $(error Toolchain not configured for ARCv2 builds)
+endif
+endif
+
 ifdef CONFIG_ARC_CURR_IN_REG
 # For a global register defintion, make sure it gets passed to every file
 # We had a customer reported bug where some code built in kernel was NOT using
@@ -48,8 +62,6 @@ endif
 
 endif
 
-cflags-$(CONFIG_ARC_DW2_UNWIND)		+= -fasynchronous-unwind-tables
-
 # By default gcc 4.8 generates dwarf4 which kernel unwinder can't grok
 ifeq ($(atleast_gcc48),y)
 cflags-$(CONFIG_ARC_DW2_UNWIND)		+= -gdwarf-2
diff --git a/kernel/arch/arc/include/asm/arcregs.h b/kernel/arch/arc/include/asm/arcregs.h
index 7fac7d85e..2c30a016c 100644
--- a/kernel/arch/arc/include/asm/arcregs.h
+++ b/kernel/arch/arc/include/asm/arcregs.h
@@ -374,12 +374,6 @@ static inline int is_isa_arcompact(void)
 	return IS_ENABLED(CONFIG_ISA_ARCOMPACT);
 }
 
-#if defined(CONFIG_ISA_ARCOMPACT) && !defined(_CPU_DEFAULT_A7)
-#error "Toolchain not configured for ARCompact builds"
-#elif defined(CONFIG_ISA_ARCV2) && !defined(_CPU_DEFAULT_HS)
-#error "Toolchain not configured for ARCv2 builds"
-#endif
-
 #endif /* __ASEMBLY__ */
 
 #endif /* _ASM_ARC_ARCREGS_H */
diff --git a/kernel/arch/arc/include/asm/bitops.h b/kernel/arch/arc/include/asm/bitops.h
index 57c1f3384..0352fb8d2 100644
--- a/kernel/arch/arc/include/asm/bitops.h
+++ b/kernel/arch/arc/include/asm/bitops.h
@@ -35,21 +35,6 @@ static inline void op##_bit(unsigned long nr, volatile unsigned long *m)\
 									\
 	m += nr >> 5;							\
 									\
-	/*								\
-	 * ARC ISA micro-optimization:					\
-	 *								\
-	 * Instructions dealing with bitpos only consider lower 5 bits	\
-	 * e.g (x << 33) is handled like (x << 1) by ASL instruction	\
-	 *  (mem pointer still needs adjustment to point to next word)	\
-	 *								\
-	 * Hence the masking to clamp @nr arg can be elided in general.	\
-	 *								\
-	 * However if @nr is a constant (above assumed in a register),	\
-	 * and greater than 31, gcc can optimize away (x << 33) to 0,	\
-	 * as overflow, given the 32-bit ISA. Thus masking needs to be	\
-	 * done for const @nr, but no code is generated due to gcc	\
-	 * const prop.							\
-	 */								\
 	nr &= 0x1f;							\
 									\
 	__asm__ __volatile__(						\
diff --git a/kernel/arch/arc/include/asm/cacheflush.h b/kernel/arch/arc/include/asm/cacheflush.h
index fbe3587c4..56aeb5efe 100644
--- a/kernel/arch/arc/include/asm/cacheflush.h
+++ b/kernel/arch/arc/include/asm/cacheflush.h
@@ -85,6 +85,10 @@ void flush_anon_page(struct vm_area_struct *vma,
  */
 #define PG_dc_clean	PG_arch_1
 
+#define CACHE_COLORS_NUM	4
+#define CACHE_COLORS_MSK	(CACHE_COLORS_NUM - 1)
+#define CACHE_COLOR(addr)	(((unsigned long)(addr) >> (PAGE_SHIFT)) & CACHE_COLORS_MSK)
+
 /*
  * Simple wrapper over config option
  * Bootup code ensures that hardware matches kernel configuration
@@ -94,8 +98,6 @@ static inline int cache_is_vipt_aliasing(void)
 	return IS_ENABLED(CONFIG_ARC_CACHE_VIPT_ALIASING);
 }
 
-#define CACHE_COLOR(addr)	(((unsigned long)(addr) >> (PAGE_SHIFT)) & 1)
-
 /*
  * checks if two addresses (after page aligning) index into same cache set
  */
diff --git a/kernel/arch/arc/include/asm/delay.h b/kernel/arch/arc/include/asm/delay.h
index 08e7e2a16..d5da2115d 100644
--- a/kernel/arch/arc/include/asm/delay.h
+++ b/kernel/arch/arc/include/asm/delay.h
@@ -22,10 +22,13 @@
 static inline void __delay(unsigned long loops)
 {
 	__asm__ __volatile__(
-	"	lp  1f	\n"
-	"	nop	\n"
-	"1:		\n"
-	: "+l"(loops));
+	"	mov lp_count, %0	\n"
+	"	lp  1f			\n"
+	"	nop			\n"
+	"1:				\n"
+	:
+        : "r"(loops)
+        : "lp_count");
 }
 
 extern void __bad_udelay(void);
diff --git a/kernel/arch/arc/include/asm/entry.h b/kernel/arch/arc/include/asm/entry.h
index ad7860c5c..51597f344 100644
--- a/kernel/arch/arc/include/asm/entry.h
+++ b/kernel/arch/arc/include/asm/entry.h
@@ -142,7 +142,7 @@
 
 #ifdef CONFIG_ARC_CURR_IN_REG
 	; Retrieve orig r25 and save it with rest of callee_regs
-	ld.as   r12, [r12, PT_user_r25]
+	ld	r12, [r12, PT_user_r25]
 	PUSH	r12
 #else
 	PUSH	r25
@@ -198,7 +198,7 @@
 
 	; SP is back to start of pt_regs
 #ifdef CONFIG_ARC_CURR_IN_REG
-	st.as   r12, [sp, PT_user_r25]
+	st	r12, [sp, PT_user_r25]
 #endif
 .endm
 
diff --git a/kernel/arch/arc/include/asm/io.h b/kernel/arch/arc/include/asm/io.h
index 694ece8a0..cb69299a4 100644
--- a/kernel/arch/arc/include/asm/io.h
+++ b/kernel/arch/arc/include/asm/io.h
@@ -13,6 +13,15 @@
 #include <asm/byteorder.h>
 #include <asm/page.h>
 
+#ifdef CONFIG_ISA_ARCV2
+#include <asm/barrier.h>
+#define __iormb()		rmb()
+#define __iowmb()		wmb()
+#else
+#define __iormb()		do { } while (0)
+#define __iowmb()		do { } while (0)
+#endif
+
 extern void __iomem *ioremap(unsigned long physaddr, unsigned long size);
 extern void __iomem *ioremap_prot(phys_addr_t offset, unsigned long size,
 				  unsigned long flags);
@@ -22,6 +31,15 @@ extern void iounmap(const void __iomem *addr);
 #define ioremap_wc(phy, sz)		ioremap(phy, sz)
 #define ioremap_wt(phy, sz)		ioremap(phy, sz)
 
+/*
+ * io{read,write}{16,32}be() macros
+ */
+#define ioread16be(p)		({ u16 __v = be16_to_cpu((__force __be16)__raw_readw(p)); __iormb(); __v; })
+#define ioread32be(p)		({ u32 __v = be32_to_cpu((__force __be32)__raw_readl(p)); __iormb(); __v; })
+
+#define iowrite16be(v,p)	({ __iowmb(); __raw_writew((__force u16)cpu_to_be16(v), p); })
+#define iowrite32be(v,p)	({ __iowmb(); __raw_writel((__force u32)cpu_to_be32(v), p); })
+
 /* Change struct page to physical address */
 #define page_to_phys(page)		(page_to_pfn(page) << PAGE_SHIFT)
 
@@ -99,15 +117,6 @@ static inline void __raw_writel(u32 w, volatile void __iomem *addr)
 
 }
 
-#ifdef CONFIG_ISA_ARCV2
-#include <asm/barrier.h>
-#define __iormb()		rmb()
-#define __iowmb()		wmb()
-#else
-#define __iormb()		do { } while (0)
-#define __iowmb()		do { } while (0)
-#endif
-
 /*
  * MMIO can also get buffered/optimized in micro-arch, so barriers needed
  * Based on ARM model for the typical use case
@@ -129,15 +138,23 @@ static inline void __raw_writel(u32 w, volatile void __iomem *addr)
 #define writel(v,c)		({ __iowmb(); writel_relaxed(v,c); })
 
 /*
- * Relaxed API for drivers which can handle any ordering themselves
+ * Relaxed API for drivers which can handle barrier ordering themselves
+ *
+ * Also these are defined to perform little endian accesses.
+ * To provide the typical device register semantics of fixed endian,
+ * swap the byte order for Big Endian
+ *
+ * http://lkml.kernel.org/r/201603100845.30602.arnd@arndb.de
  */
 #define readb_relaxed(c)	__raw_readb(c)
-#define readw_relaxed(c)	__raw_readw(c)
-#define readl_relaxed(c)	__raw_readl(c)
+#define readw_relaxed(c) ({ u16 __r = le16_to_cpu((__force __le16) \
+					__raw_readw(c)); __r; })
+#define readl_relaxed(c) ({ u32 __r = le32_to_cpu((__force __le32) \
+					__raw_readl(c)); __r; })
 
 #define writeb_relaxed(v,c)	__raw_writeb(v,c)
-#define writew_relaxed(v,c)	__raw_writew(v,c)
-#define writel_relaxed(v,c)	__raw_writel(v,c)
+#define writew_relaxed(v,c)	__raw_writew((__force u16) cpu_to_le16(v),c)
+#define writel_relaxed(v,c)	__raw_writel((__force u32) cpu_to_le32(v),c)
 
 #include <asm-generic/io.h>
 
diff --git a/kernel/arch/arc/include/asm/irqflags-compact.h b/kernel/arch/arc/include/asm/irqflags-compact.h
index c1d36458b..4c6eed80c 100644
--- a/kernel/arch/arc/include/asm/irqflags-compact.h
+++ b/kernel/arch/arc/include/asm/irqflags-compact.h
@@ -188,10 +188,10 @@ static inline int arch_irqs_disabled(void)
 .endm
 
 .macro IRQ_ENABLE  scratch
+	TRACE_ASM_IRQ_ENABLE
 	lr	\scratch, [status32]
 	or	\scratch, \scratch, (STATUS_E1_MASK | STATUS_E2_MASK)
 	flag	\scratch
-	TRACE_ASM_IRQ_ENABLE
 .endm
 
 #endif	/* __ASSEMBLY__ */
diff --git a/kernel/arch/arc/include/asm/pgtable.h b/kernel/arch/arc/include/asm/pgtable.h
index 57af2f05a..e5fec320f 100644
--- a/kernel/arch/arc/include/asm/pgtable.h
+++ b/kernel/arch/arc/include/asm/pgtable.h
@@ -110,7 +110,7 @@
 #define ___DEF (_PAGE_PRESENT | _PAGE_CACHEABLE)
 
 /* Set of bits not changed in pte_modify */
-#define _PAGE_CHG_MASK	(PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
+#define _PAGE_CHG_MASK	(PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY | _PAGE_SPECIAL)
 
 /* More Abbrevaited helpers */
 #define PAGE_U_NONE     __pgprot(___DEF)
@@ -277,8 +277,7 @@ static inline void pmd_set(pmd_t *pmdp, pte_t *ptep)
 
 #define mk_pte(page, prot)	pfn_pte(page_to_pfn(page), prot)
 #define pte_pfn(pte)		(pte_val(pte) >> PAGE_SHIFT)
-#define pfn_pte(pfn, prot)	(__pte(((pte_t)(pfn) << PAGE_SHIFT) | \
-				 pgprot_val(prot)))
+#define pfn_pte(pfn, prot)	(__pte(((pfn) << PAGE_SHIFT) | pgprot_val(prot)))
 #define __pte_index(addr)	(((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
 
 /*
diff --git a/kernel/arch/arc/include/asm/uaccess.h b/kernel/arch/arc/include/asm/uaccess.h
index d1da6032b..d4d8df706 100644
--- a/kernel/arch/arc/include/asm/uaccess.h
+++ b/kernel/arch/arc/include/asm/uaccess.h
@@ -83,7 +83,10 @@
 	"2:	;nop\n"				\
 	"	.section .fixup, \"ax\"\n"	\
 	"	.align 4\n"			\
-	"3:	mov %0, %3\n"			\
+	"3:	# return -EFAULT\n"		\
+	"	mov %0, %3\n"			\
+	"	# zero out dst ptr\n"		\
+	"	mov %1,  0\n"			\
 	"	j   2b\n"			\
 	"	.previous\n"			\
 	"	.section __ex_table, \"a\"\n"	\
@@ -101,7 +104,11 @@
 	"2:	;nop\n"				\
 	"	.section .fixup, \"ax\"\n"	\
 	"	.align 4\n"			\
-	"3:	mov %0, %3\n"			\
+	"3:	# return -EFAULT\n"		\
+	"	mov %0, %3\n"			\
+	"	# zero out dst ptr\n"		\
+	"	mov %1,  0\n"			\
+	"	mov %R1, 0\n"			\
 	"	j   2b\n"			\
 	"	.previous\n"			\
 	"	.section __ex_table, \"a\"\n"	\
diff --git a/kernel/arch/arc/kernel/setup.c b/kernel/arch/arc/kernel/setup.c
index e1b87444e..05131805a 100644
--- a/kernel/arch/arc/kernel/setup.c
+++ b/kernel/arch/arc/kernel/setup.c
@@ -332,10 +332,6 @@ static void arc_chk_core_config(void)
 		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");
-
-	if (is_isa_arcv2() && IS_ENABLED(CONFIG_SMP) && cpu->isa.atomic &&
-	    !IS_ENABLED(CONFIG_ARC_STAR_9000923308))
-		panic("llock/scond livelock workaround missing\n");
 }
 
 /*
diff --git a/kernel/arch/arc/kernel/signal.c b/kernel/arch/arc/kernel/signal.c
index 004b7f0bc..257b8699e 100644
--- a/kernel/arch/arc/kernel/signal.c
+++ b/kernel/arch/arc/kernel/signal.c
@@ -107,13 +107,13 @@ static int restore_usr_regs(struct pt_regs *regs, struct rt_sigframe __user *sf)
 	struct user_regs_struct uregs;
 
 	err = __copy_from_user(&set, &sf->uc.uc_sigmask, sizeof(set));
-	if (!err)
-		set_current_blocked(&set);
-
 	err |= __copy_from_user(&uregs.scratch,
 				&(sf->uc.uc_mcontext.regs.scratch),
 				sizeof(sf->uc.uc_mcontext.regs.scratch));
+	if (err)
+		return err;
 
+	set_current_blocked(&set);
 	regs->bta	= uregs.scratch.bta;
 	regs->lp_start	= uregs.scratch.lp_start;
 	regs->lp_end	= uregs.scratch.lp_end;
@@ -138,7 +138,7 @@ static int restore_usr_regs(struct pt_regs *regs, struct rt_sigframe __user *sf)
 	regs->r0	= uregs.scratch.r0;
 	regs->sp	= uregs.scratch.sp;
 
-	return err;
+	return 0;
 }
 
 static inline int is_do_ss_needed(unsigned int magic)
diff --git a/kernel/arch/arc/kernel/stacktrace.c b/kernel/arch/arc/kernel/stacktrace.c
index 001de4ce7..11b50959f 100644
--- a/kernel/arch/arc/kernel/stacktrace.c
+++ b/kernel/arch/arc/kernel/stacktrace.c
@@ -142,7 +142,7 @@ arc_unwind_core(struct task_struct *tsk, struct pt_regs *regs,
 	 * prelogue is setup (callee regs saved and then fp set and not other
 	 * way around
 	 */
-	pr_warn("CONFIG_ARC_DW2_UNWIND needs to be enabled\n");
+	pr_warn_once("CONFIG_ARC_DW2_UNWIND needs to be enabled\n");
 	return 0;
 
 #endif
diff --git a/kernel/arch/arc/kernel/time.c b/kernel/arch/arc/kernel/time.c
index dfad287f1..dbedc576e 100644
--- a/kernel/arch/arc/kernel/time.c
+++ b/kernel/arch/arc/kernel/time.c
@@ -130,14 +130,17 @@ static cycle_t arc_counter_read(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/kernel/arch/arc/kernel/unaligned.c b/kernel/arch/arc/kernel/unaligned.c
index abd961f3e..5f69c3bd5 100644
--- a/kernel/arch/arc/kernel/unaligned.c
+++ b/kernel/arch/arc/kernel/unaligned.c
@@ -241,8 +241,9 @@ int misaligned_fixup(unsigned long address, struct pt_regs *regs,
 	if (state.fault)
 		goto fault;
 
+	/* clear any remanants of delay slot */
 	if (delay_mode(regs)) {
-		regs->ret = regs->bta;
+		regs->ret = regs->bta & ~1U;
 		regs->status32 &= ~STATUS_DE_MASK;
 	} else {
 		regs->ret += state.instr_len;
diff --git a/kernel/arch/arc/mm/cache.c b/kernel/arch/arc/mm/cache.c
index ff7ff6cbb..d81b6d7e1 100644
--- a/kernel/arch/arc/mm/cache.c
+++ b/kernel/arch/arc/mm/cache.c
@@ -914,6 +914,15 @@ void arc_cache_init(void)
 
 	printk(arc_cache_mumbojumbo(0, str, sizeof(str)));
 
+	/*
+	 * Only master CPU needs to execute rest of function:
+	 *  - Assume SMP so all cores will have same cache config so
+	 *    any geomtry checks will be same for all
+	 *  - IOC setup / dma callbacks only need to be setup once
+	 */
+	if (cpu)
+		return;
+
 	if (IS_ENABLED(CONFIG_ARC_HAS_ICACHE)) {
 		struct cpuinfo_arc_cache *ic = &cpuinfo_arc700[cpu].icache;
 
@@ -951,11 +960,16 @@ void arc_cache_init(void)
 		/* check for D-Cache aliasing on ARCompact: ARCv2 has PIPT */
 		if (is_isa_arcompact()) {
 			int handled = IS_ENABLED(CONFIG_ARC_CACHE_VIPT_ALIASING);
-
-			if (dc->alias && !handled)
-				panic("Enable CONFIG_ARC_CACHE_VIPT_ALIASING\n");
-			else if (!dc->alias && handled)
+			int num_colors = dc->sz_k/dc->assoc/TO_KB(PAGE_SIZE);
+
+			if (dc->alias) {
+				if (!handled)
+					panic("Enable CONFIG_ARC_CACHE_VIPT_ALIASING\n");
+				if (CACHE_COLORS_NUM != num_colors)
+					panic("CACHE_COLORS_NUM not optimized for config\n");
+			} else if (!dc->alias && handled) {
 				panic("Disable CONFIG_ARC_CACHE_VIPT_ALIASING\n");
+			}
 		}
 	}