Merge tag 'mips_4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux

Pull MIPS updates from Paul Burton:
 "Here's the main MIPS pull for Linux 4.21. Core architecture changes
  include:

   - Syscall tables & definitions for unistd.h are now generated by
     scripts, providing greater consistency with other architectures &
     making it easier to add new syscalls.

   - Support for building kernels with no floating point support, upon
     which any userland attempting to use floating point instructions
     will receive a SIGILL. Mostly useful to shrink the kernel & as
     preparation for nanoMIPS support which does not yet include FP.

   - MIPS SIMD Architecture (MSA) vector register context is now exposed
     by ptrace via a new NT_MIPS_MSA regset.

   - ASIDs are now stored as 64b values even for MIPS32 kernels,
     expanding the ASID version field sufficiently that we don't need to
     worry about overflow & avoiding rare issues with reused ASIDs that
     have been observed in the wild.

   - The branch delay slot "emulation" page is now mapped without write
     permission for the user, preventing its use as a nice location for
     attacks to execute malicious code from.

   - Support for ioremap_prot(), primarily to allow gdb or other ptrace
     users the ability to view their tracee's memory using the same
     cache coherency attribute.

   - Optimizations to more cpu_has_* macros, allowing more to be
     compile-time constant where possible.

   - Enable building the whole kernel with UBSAN instrumentation.

   - Enable building the kernel with link-time dead code & data
     elimination.

  Platform specific changes include:

   - The Boston board gains a workaround for DMA prefetching issues with
     the EG20T Platform Controller Hub that it uses.

   - Cleanups to Cavium Octeon code removing about 20k lines of
     redundant code, mostly unused or duplicate register definitions in
     headers.

   - defconfig updates for the DECstation machines, including new
     defconfigs for r4k & 64b machines.

   - Further work on Loongson 3 support.

   - DMA fixes for SiByte machines"

* tag 'mips_4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: (95 commits)
  MIPS: math-emu: Write-protect delay slot emulation pages
  MIPS: Remove struct mm_context_t fp_mode_switching field
  mips: generate uapi header and system call table files
  mips: add system call table generation support
  mips: remove syscall table entries
  mips: add +1 to __NR_syscalls in uapi header
  mips: rename scall64-64.S to scall64-n64.S
  mips: remove unused macros
  mips: add __NR_syscalls along with __NR_Linux_syscalls
  MIPS: Expand MIPS32 ASIDs to 64 bits
  MIPS: OCTEON: delete redundant register definitions
  MIPS: OCTEON: cvmx_gmxx_inf_mode: use oldest forward compatible definition
  MIPS: OCTEON: cvmx_mio_fus_dat3: use oldest forward compatible definition
  MIPS: OCTEON: cvmx_pko_mem_debug8: use oldest forward compatible definition
  MIPS: OCTEON: octeon-usb: use common gpio_bit definition
  MIPS: OCTEON: enable all OCTEON drivers in defconfig
  mips: annotate implicit fall throughs
  MIPS: Hardcode cpu_has_mips* where target ISA allows
  MIPS: MT: Remove norps command line parameter
  MIPS: Only include mmzone.h when CONFIG_NEED_MULTIPLE_NODES=y
  ...

1 files changed, 50 insertions, 14 deletions

diff --git a/arch/mips/kernel/cpu-probe.c b/arch/mips/kernel/cpu-probe.c
index d535fc706a8b..95b18a194f53 100644
--- a/arch/mips/kernel/cpu-probe.c
+++ b/arch/mips/kernel/cpu-probe.c
@@ -36,6 +36,8 @@
 unsigned int elf_hwcap __read_mostly;
 EXPORT_SYMBOL_GPL(elf_hwcap);
 
+#ifdef CONFIG_MIPS_FP_SUPPORT
+
 /*
  * Get the FPU Implementation/Revision.
  */
@@ -58,19 +60,6 @@ static inline int __cpu_has_fpu(void)
 	return (cpu_get_fpu_id() & FPIR_IMP_MASK) != FPIR_IMP_NONE;
 }
 
-static inline unsigned long cpu_get_msa_id(void)
-{
-	unsigned long status, msa_id;
-
-	status = read_c0_status();
-	__enable_fpu(FPU_64BIT);
-	enable_msa();
-	msa_id = read_msa_ir();
-	disable_msa();
-	write_c0_status(status);
-	return msa_id;
-}
-
 /*
  * Determine the FCSR mask for FPU hardware.
  */
@@ -326,6 +315,45 @@ static int __init fpu_disable(char *s)
 
 __setup("nofpu", fpu_disable);
 
+#else /* !CONFIG_MIPS_FP_SUPPORT */
+
+#define mips_fpu_disabled 1
+
+static inline unsigned long cpu_get_fpu_id(void)
+{
+	return FPIR_IMP_NONE;
+}
+
+static inline int __cpu_has_fpu(void)
+{
+	return 0;
+}
+
+static void cpu_set_fpu_opts(struct cpuinfo_mips *c)
+{
+	/* no-op */
+}
+
+static void cpu_set_nofpu_opts(struct cpuinfo_mips *c)
+{
+	/* no-op */
+}
+
+#endif /* CONFIG_MIPS_FP_SUPPORT */
+
+static inline unsigned long cpu_get_msa_id(void)
+{
+	unsigned long status, msa_id;
+
+	status = read_c0_status();
+	__enable_fpu(FPU_64BIT);
+	enable_msa();
+	msa_id = read_msa_ir();
+	disable_msa();
+	write_c0_status(status);
+	return msa_id;
+}
+
 static int mips_dsp_disabled;
 
 static int __init dsp_disable(char *s)
@@ -489,12 +517,16 @@ static void set_isa(struct cpuinfo_mips *c, unsigned int isa)
 	switch (isa) {
 	case MIPS_CPU_ISA_M64R2:
 		c->isa_level |= MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2;
+		/* fall through */
 	case MIPS_CPU_ISA_M64R1:
 		c->isa_level |= MIPS_CPU_ISA_M32R1 | MIPS_CPU_ISA_M64R1;
+		/* fall through */
 	case MIPS_CPU_ISA_V:
 		c->isa_level |= MIPS_CPU_ISA_V;
+		/* fall through */
 	case MIPS_CPU_ISA_IV:
 		c->isa_level |= MIPS_CPU_ISA_IV;
+		/* fall through */
 	case MIPS_CPU_ISA_III:
 		c->isa_level |= MIPS_CPU_ISA_II | MIPS_CPU_ISA_III;
 		break;
@@ -502,14 +534,17 @@ static void set_isa(struct cpuinfo_mips *c, unsigned int isa)
 	/* R6 incompatible with everything else */
 	case MIPS_CPU_ISA_M64R6:
 		c->isa_level |= MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R6;
+		/* fall through */
 	case MIPS_CPU_ISA_M32R6:
 		c->isa_level |= MIPS_CPU_ISA_M32R6;
 		/* Break here so we don't add incompatible ISAs */
 		break;
 	case MIPS_CPU_ISA_M32R2:
 		c->isa_level |= MIPS_CPU_ISA_M32R2;
+		/* fall through */
 	case MIPS_CPU_ISA_M32R1:
 		c->isa_level |= MIPS_CPU_ISA_M32R1;
+		/* fall through */
 	case MIPS_CPU_ISA_II:
 		c->isa_level |= MIPS_CPU_ISA_II;
 		break;
@@ -1843,7 +1878,8 @@ static inline void cpu_probe_loongson(struct cpuinfo_mips *c, unsigned int cpu)
 	switch (c->processor_id & PRID_IMP_MASK) {
 	case PRID_IMP_LOONGSON_64:  /* Loongson-2/3 */
 		switch (c->processor_id & PRID_REV_MASK) {
-		case PRID_REV_LOONGSON3A_R2:
+		case PRID_REV_LOONGSON3A_R2_0:
+		case PRID_REV_LOONGSON3A_R2_1:
 			c->cputype = CPU_LOONGSON3;
 			__cpu_name[cpu] = "ICT Loongson-3";
 			set_elf_platform(cpu, "loongson3a");