Merge tag 'mips_4.19_2' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux

Pull MIPS fixes from Paul Burton:

  - Fix microMIPS build failures by adding a .insn directive to the
    barrier_before_unreachable() asm statement in order to convince the
    toolchain that the asm statement is a valid branch target rather
    than a bogus attempt to switch ISA.

  - Clean up our declarations of TLB functions that we overwrite with
    generated code in order to prevent the compiler making assumptions
    about alignment that cause microMIPS kernels built with GCC 7 &
    above to die early during boot.

  - Fix up a regression for MIPS32 kernels which slipped into the main
    MIPS pull for 4.19, causing CONFIG_32BIT=y kernels to contain
    inappropriate MIPS64 instructions.

  - Extend our existing workaround for MIPSr6 builds that end up using
    the __multi3 intrinsic to GCC 7 & below, rather than just GCC 7.

* tag 'mips_4.19_2' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
  MIPS: lib: Provide MIPS64r6 __multi3() for GCC < 7
  MIPS: Workaround GCC __builtin_unreachable reordering bug
  compiler.h: Allow arch-specific asm/compiler.h
  MIPS: Avoid move psuedo-instruction whilst using MIPS_ISA_LEVEL
  MIPS: Consistently declare TLB functions
  MIPS: Export tlbmiss_handler_setup_pgd near its definition

2 files changed, 42 insertions, 62 deletions

diff --git a/arch/mips/mm/tlb-funcs.S b/arch/mips/mm/tlb-funcs.S
index a5427c6e9757..00fef578c8cd 100644
--- a/arch/mips/mm/tlb-funcs.S
+++ b/arch/mips/mm/tlb-funcs.S
@@ -12,16 +12,17 @@
  * Copyright (C) 2012  Ralf Baechle <ralf@linux-mips.org>
  */
 #include <asm/asm.h>
+#include <asm/export.h>
 #include <asm/regdef.h>
 
 #define FASTPATH_SIZE	128
 
-EXPORT(tlbmiss_handler_setup_pgd_start)
 LEAF(tlbmiss_handler_setup_pgd)
 1:	j	1b		/* Dummy, will be replaced. */
 	.space	64
 END(tlbmiss_handler_setup_pgd)
 EXPORT(tlbmiss_handler_setup_pgd_end)
+EXPORT_SYMBOL_GPL(tlbmiss_handler_setup_pgd)
 
 LEAF(handle_tlbm)
 	.space		FASTPATH_SIZE * 4
diff --git a/arch/mips/mm/tlbex.c b/arch/mips/mm/tlbex.c
index 49312a14cd17..067714291643 100644
--- a/arch/mips/mm/tlbex.c
+++ b/arch/mips/mm/tlbex.c
@@ -31,6 +31,7 @@
 
 #include <asm/cacheflush.h>
 #include <asm/cpu-type.h>
+#include <asm/mmu_context.h>
 #include <asm/pgtable.h>
 #include <asm/war.h>
 #include <asm/uasm.h>
@@ -253,8 +254,10 @@ static void output_pgtable_bits_defines(void)
 	pr_debug("\n");
 }
 
-static inline void dump_handler(const char *symbol, const u32 *handler, int count)
+static inline void dump_handler(const char *symbol, const void *start, const void *end)
 {
+	unsigned int count = (end - start) / sizeof(u32);
+	const u32 *handler = start;
 	int i;
 
 	pr_debug("LEAF(%s)\n", symbol);
@@ -402,12 +405,6 @@ static void build_restore_work_registers(u32 **p)
  * CONFIG_MIPS_PGD_C0_CONTEXT implies 64 bit and lack of pgd_current,
  * we cannot do r3000 under these circumstances.
  *
- * Declare pgd_current here instead of including mmu_context.h to avoid type
- * conflicts for tlbmiss_handler_setup_pgd
- */
-extern unsigned long pgd_current[];
-
-/*
  * The R3000 TLB handler is simple.
  */
 static void build_r3000_tlb_refill_handler(void)
@@ -444,8 +441,7 @@ static void build_r3000_tlb_refill_handler(void)
 
 	memcpy((void *)ebase, tlb_handler, 0x80);
 	local_flush_icache_range(ebase, ebase + 0x80);
-
-	dump_handler("r3000_tlb_refill", (u32 *)ebase, 32);
+	dump_handler("r3000_tlb_refill", (u32 *)ebase, (u32 *)(ebase + 0x80));
 }
 #endif /* CONFIG_MIPS_PGD_C0_CONTEXT */
 
@@ -1465,8 +1461,7 @@ static void build_r4000_tlb_refill_handler(void)
 
 	memcpy((void *)ebase, final_handler, 0x100);
 	local_flush_icache_range(ebase, ebase + 0x100);
-
-	dump_handler("r4000_tlb_refill", (u32 *)ebase, 64);
+	dump_handler("r4000_tlb_refill", (u32 *)ebase, (u32 *)(ebase + 0x100));
 }
 
 static void setup_pw(void)
@@ -1568,31 +1563,21 @@ static void build_loongson3_tlb_refill_handler(void)
 	uasm_resolve_relocs(relocs, labels);
 	memcpy((void *)(ebase + 0x80), tlb_handler, 0x80);
 	local_flush_icache_range(ebase + 0x80, ebase + 0x100);
-	dump_handler("loongson3_tlb_refill", (u32 *)(ebase + 0x80), 32);
+	dump_handler("loongson3_tlb_refill",
+		     (u32 *)(ebase + 0x80), (u32 *)(ebase + 0x100));
 }
 
-extern u32 handle_tlbl[], handle_tlbl_end[];
-extern u32 handle_tlbs[], handle_tlbs_end[];
-extern u32 handle_tlbm[], handle_tlbm_end[];
-extern u32 tlbmiss_handler_setup_pgd_start[];
-extern u32 tlbmiss_handler_setup_pgd[];
-EXPORT_SYMBOL_GPL(tlbmiss_handler_setup_pgd);
-extern u32 tlbmiss_handler_setup_pgd_end[];
-
 static void build_setup_pgd(void)
 {
 	const int a0 = 4;
 	const int __maybe_unused a1 = 5;
 	const int __maybe_unused a2 = 6;
-	u32 *p = tlbmiss_handler_setup_pgd_start;
-	const int tlbmiss_handler_setup_pgd_size =
-		tlbmiss_handler_setup_pgd_end - tlbmiss_handler_setup_pgd_start;
+	u32 *p = (u32 *)msk_isa16_mode((ulong)tlbmiss_handler_setup_pgd);
 #ifndef CONFIG_MIPS_PGD_C0_CONTEXT
 	long pgdc = (long)pgd_current;
 #endif
 
-	memset(tlbmiss_handler_setup_pgd, 0, tlbmiss_handler_setup_pgd_size *
-					sizeof(tlbmiss_handler_setup_pgd[0]));
+	memset(p, 0, tlbmiss_handler_setup_pgd_end - (char *)p);
 	memset(labels, 0, sizeof(labels));
 	memset(relocs, 0, sizeof(relocs));
 	pgd_reg = allocate_kscratch();
@@ -1645,15 +1630,15 @@ static void build_setup_pgd(void)
 	else
 		uasm_i_nop(&p);
 #endif
-	if (p >= tlbmiss_handler_setup_pgd_end)
+	if (p >= (u32 *)tlbmiss_handler_setup_pgd_end)
 		panic("tlbmiss_handler_setup_pgd space exceeded");
 
 	uasm_resolve_relocs(relocs, labels);
 	pr_debug("Wrote tlbmiss_handler_setup_pgd (%u instructions).\n",
-		 (unsigned int)(p - tlbmiss_handler_setup_pgd));
+		 (unsigned int)(p - (u32 *)tlbmiss_handler_setup_pgd));
 
 	dump_handler("tlbmiss_handler", tlbmiss_handler_setup_pgd,
-					tlbmiss_handler_setup_pgd_size);
+					tlbmiss_handler_setup_pgd_end);
 }
 
 static void
@@ -1922,12 +1907,11 @@ build_r3000_tlbchange_handler_head(u32 **p, unsigned int pte,
 
 static void build_r3000_tlb_load_handler(void)
 {
-	u32 *p = handle_tlbl;
-	const int handle_tlbl_size = handle_tlbl_end - handle_tlbl;
+	u32 *p = (u32 *)handle_tlbl;
 	struct uasm_label *l = labels;
 	struct uasm_reloc *r = relocs;
 
-	memset(handle_tlbl, 0, handle_tlbl_size * sizeof(handle_tlbl[0]));
+	memset(p, 0, handle_tlbl_end - (char *)p);
 	memset(labels, 0, sizeof(labels));
 	memset(relocs, 0, sizeof(relocs));
 
@@ -1941,24 +1925,23 @@ static void build_r3000_tlb_load_handler(void)
 	uasm_i_j(&p, (unsigned long)tlb_do_page_fault_0 & 0x0fffffff);
 	uasm_i_nop(&p);
 
-	if (p >= handle_tlbl_end)
+	if (p >= (u32 *)handle_tlbl_end)
 		panic("TLB load handler fastpath space exceeded");
 
 	uasm_resolve_relocs(relocs, labels);
 	pr_debug("Wrote TLB load handler fastpath (%u instructions).\n",
-		 (unsigned int)(p - handle_tlbl));
+		 (unsigned int)(p - (u32 *)handle_tlbl));
 
-	dump_handler("r3000_tlb_load", handle_tlbl, handle_tlbl_size);
+	dump_handler("r3000_tlb_load", handle_tlbl, handle_tlbl_end);
 }
 
 static void build_r3000_tlb_store_handler(void)
 {
-	u32 *p = handle_tlbs;
-	const int handle_tlbs_size = handle_tlbs_end - handle_tlbs;
+	u32 *p = (u32 *)handle_tlbs;
 	struct uasm_label *l = labels;
 	struct uasm_reloc *r = relocs;
 
-	memset(handle_tlbs, 0, handle_tlbs_size * sizeof(handle_tlbs[0]));
+	memset(p, 0, handle_tlbs_end - (char *)p);
 	memset(labels, 0, sizeof(labels));
 	memset(relocs, 0, sizeof(relocs));
 
@@ -1972,24 +1955,23 @@ static void build_r3000_tlb_store_handler(void)
 	uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff);
 	uasm_i_nop(&p);
 
-	if (p >= handle_tlbs_end)
+	if (p >= (u32 *)handle_tlbs_end)
 		panic("TLB store handler fastpath space exceeded");
 
 	uasm_resolve_relocs(relocs, labels);
 	pr_debug("Wrote TLB store handler fastpath (%u instructions).\n",
-		 (unsigned int)(p - handle_tlbs));
+		 (unsigned int)(p - (u32 *)handle_tlbs));
 
-	dump_handler("r3000_tlb_store", handle_tlbs, handle_tlbs_size);
+	dump_handler("r3000_tlb_store", handle_tlbs, handle_tlbs_end);
 }
 
 static void build_r3000_tlb_modify_handler(void)
 {
-	u32 *p = handle_tlbm;
-	const int handle_tlbm_size = handle_tlbm_end - handle_tlbm;
+	u32 *p = (u32 *)handle_tlbm;
 	struct uasm_label *l = labels;
 	struct uasm_reloc *r = relocs;
 
-	memset(handle_tlbm, 0, handle_tlbm_size * sizeof(handle_tlbm[0]));
+	memset(p, 0, handle_tlbm_end - (char *)p);
 	memset(labels, 0, sizeof(labels));
 	memset(relocs, 0, sizeof(relocs));
 
@@ -2003,14 +1985,14 @@ static void build_r3000_tlb_modify_handler(void)
 	uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff);
 	uasm_i_nop(&p);
 
-	if (p >= handle_tlbm_end)
+	if (p >= (u32 *)handle_tlbm_end)
 		panic("TLB modify handler fastpath space exceeded");
 
 	uasm_resolve_relocs(relocs, labels);
 	pr_debug("Wrote TLB modify handler fastpath (%u instructions).\n",
-		 (unsigned int)(p - handle_tlbm));
+		 (unsigned int)(p - (u32 *)handle_tlbm));
 
-	dump_handler("r3000_tlb_modify", handle_tlbm, handle_tlbm_size);
+	dump_handler("r3000_tlb_modify", handle_tlbm, handle_tlbm_end);
 }
 #endif /* CONFIG_MIPS_PGD_C0_CONTEXT */
 
@@ -2102,12 +2084,11 @@ build_r4000_tlbchange_handler_tail(u32 **p, struct uasm_label **l,
 static void build_r4000_tlb_load_handler(void)
 {
 	u32 *p = (u32 *)msk_isa16_mode((ulong)handle_tlbl);
-	const int handle_tlbl_size = handle_tlbl_end - handle_tlbl;
 	struct uasm_label *l = labels;
 	struct uasm_reloc *r = relocs;
 	struct work_registers wr;
 
-	memset(handle_tlbl, 0, handle_tlbl_size * sizeof(handle_tlbl[0]));
+	memset(p, 0, handle_tlbl_end - (char *)p);
 	memset(labels, 0, sizeof(labels));
 	memset(relocs, 0, sizeof(relocs));
 
@@ -2288,25 +2269,24 @@ static void build_r4000_tlb_load_handler(void)
 	uasm_i_j(&p, (unsigned long)tlb_do_page_fault_0 & 0x0fffffff);
 	uasm_i_nop(&p);
 
-	if (p >= handle_tlbl_end)
+	if (p >= (u32 *)handle_tlbl_end)
 		panic("TLB load handler fastpath space exceeded");
 
 	uasm_resolve_relocs(relocs, labels);
 	pr_debug("Wrote TLB load handler fastpath (%u instructions).\n",
-		 (unsigned int)(p - handle_tlbl));
+		 (unsigned int)(p - (u32 *)handle_tlbl));
 
-	dump_handler("r4000_tlb_load", handle_tlbl, handle_tlbl_size);
+	dump_handler("r4000_tlb_load", handle_tlbl, handle_tlbl_end);
 }
 
 static void build_r4000_tlb_store_handler(void)
 {
 	u32 *p = (u32 *)msk_isa16_mode((ulong)handle_tlbs);
-	const int handle_tlbs_size = handle_tlbs_end - handle_tlbs;
 	struct uasm_label *l = labels;
 	struct uasm_reloc *r = relocs;
 	struct work_registers wr;
 
-	memset(handle_tlbs, 0, handle_tlbs_size * sizeof(handle_tlbs[0]));
+	memset(p, 0, handle_tlbs_end - (char *)p);
 	memset(labels, 0, sizeof(labels));
 	memset(relocs, 0, sizeof(relocs));
 
@@ -2343,25 +2323,24 @@ static void build_r4000_tlb_store_handler(void)
 	uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff);
 	uasm_i_nop(&p);
 
-	if (p >= handle_tlbs_end)
+	if (p >= (u32 *)handle_tlbs_end)
 		panic("TLB store handler fastpath space exceeded");
 
 	uasm_resolve_relocs(relocs, labels);
 	pr_debug("Wrote TLB store handler fastpath (%u instructions).\n",
-		 (unsigned int)(p - handle_tlbs));
+		 (unsigned int)(p - (u32 *)handle_tlbs));
 
-	dump_handler("r4000_tlb_store", handle_tlbs, handle_tlbs_size);
+	dump_handler("r4000_tlb_store", handle_tlbs, handle_tlbs_end);
 }
 
 static void build_r4000_tlb_modify_handler(void)
 {
 	u32 *p = (u32 *)msk_isa16_mode((ulong)handle_tlbm);
-	const int handle_tlbm_size = handle_tlbm_end - handle_tlbm;
 	struct uasm_label *l = labels;
 	struct uasm_reloc *r = relocs;
 	struct work_registers wr;
 
-	memset(handle_tlbm, 0, handle_tlbm_size * sizeof(handle_tlbm[0]));
+	memset(p, 0, handle_tlbm_end - (char *)p);
 	memset(labels, 0, sizeof(labels));
 	memset(relocs, 0, sizeof(relocs));
 
@@ -2399,14 +2378,14 @@ static void build_r4000_tlb_modify_handler(void)
 	uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff);
 	uasm_i_nop(&p);
 
-	if (p >= handle_tlbm_end)
+	if (p >= (u32 *)handle_tlbm_end)
 		panic("TLB modify handler fastpath space exceeded");
 
 	uasm_resolve_relocs(relocs, labels);
 	pr_debug("Wrote TLB modify handler fastpath (%u instructions).\n",
-		 (unsigned int)(p - handle_tlbm));
+		 (unsigned int)(p - (u32 *)handle_tlbm));
 
-	dump_handler("r4000_tlb_modify", handle_tlbm, handle_tlbm_size);
+	dump_handler("r4000_tlb_modify", handle_tlbm, handle_tlbm_end);
 }
 
 static void flush_tlb_handlers(void)