Merge tag 'mips_4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/mips

Pull MIPS updates from James Hogan:
 "These are the main MIPS changes for 4.15.

  Fixes:
   - ralink: Fix MT7620 PCI build issues (4.5)
   - Disable cmpxchg64() and HAVE_VIRT_CPU_ACCOUNTING_GEN for 32-bit SMP
     (4.1)
   - Fix MIPS64 FP save/restore on 32-bit kernels (4.0)
   - ptrace: Pick up ptrace/seccomp changed syscall numbers (3.19)
   - ralink: Fix MT7628 pinmux (3.19)
   - BCM47XX: Fix LED inversion on WRT54GSv1 (3.17)
   - Fix n32 core dumping as o32 since regset support (3.13)
   - ralink: Drop obsolete USB_ARCH_HAS_HCD select

  Build system:
   - Default to "generic" (multiplatform) system type instead of IP22
   - Use generic little endian MIPS32 r2 configuration as default
     defconfig instead of ip22_defconfig

  FPU emulation:
   - Fix exception generation for certain R6 FPU instructions

  SMP:
   - Allow __cpu_number_map to be larger than NR_CPUS for sparse CPU id
     spaces

  Miscellaneous:
   - Add iomem resource for kernel bss section for kexec/kdump
   - Atomics: Nudge writes on bit unlock
   - DT files: Standardise "ok" -> "okay"

  Minor cleanups:
   - Define virt_to_pfn()
   - Make thread_saved_pc static
   - Simplify 32-bit sign extension in __read_64bit_c0_split()
   - DMA: Use vma_pages() helper
   - FPU emulation: Replace unsigned with unsigned int
   - MM: Removed unused lastpfn
   - Alchemy: Make clk_ops const
   - Lasat: Use setup_timer() helper
   - ralink: Use BIT() in MT7620 PCI driver

  Platform support:

  BMIPS:
  - Enable HARDIRQS_SW_RESEND

  Broadcom BCM63XX:
  - Add clkdev lookup support
  - Update clk driver, UART driver, DTs to handle named refclk from DTs
  - Split apart various clocks to more closely match hardware
  - Add ethernet clocks

  Cavium Octeon:
  - Remove usage of cvmx_wait() in favour of __delay()

  ImgTec Pistachio:
  - DT: Drop deprecated dwmmc num-slots property

  Ingenic JZ4780:
  - Add NFS root to Ci20 defconfig
  - Add watchdog to Ci20 DT & defconfig, and allow building of watchdog
    driver with this SoC

  Generic (multiplatform):
  - Migrate xilfpga (MIPSfpga) platform to the generic platform

  Lantiq xway:
  - Fix ASC0/ASC1 clocks"

* tag 'mips_4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/mips: (46 commits)
  MIPS: Add iomem resource for kernel bss section.
  MIPS: cmpxchg64() and HAVE_VIRT_CPU_ACCOUNTING_GEN don't work for 32-bit SMP
  MIPS: BMIPS: Enable HARDIRQS_SW_RESEND
  MIPS: pci: Make use of the BIT() macro inside the mt7620 driver
  MIPS: pci: Remove KERN_WARN instance inside the mt7620 driver
  MIPS: pci: Remove duplicate define in mt7620 driver
  MIPS: ralink: Fix typo in mt7628 pinmux function
  MIPS: ralink: Fix MT7628 pinmux
  MIPS: Fix odd fp register warnings with MIPS64r2
  watchdog: jz4780: Allow selection of jz4740-wdt driver
  MIPS/ptrace: Update syscall nr on register changes
  MIPS/ptrace: Pick up ptrace/seccomp changed syscalls
  MIPS: Fix an n32 core file generation regset support regression
  MIPS: Fix MIPS64 FP save/restore on 32-bit kernels
  MIPS: page.h: Define virt_to_pfn()
  MIPS: Xilfpga: Switch to using generic defconfigs
  MIPS: generic: Add support for MIPSfpga
  MIPS: Set defconfig target to a generic system for 32r2el
  MIPS: Kconfig: Set default MIPS system type as generic
  MIPS: DTS: Remove num-slots from Pistachio SoC
  ...

1 files changed, 25 insertions, 4 deletions

diff --git a/arch/mips/include/asm/syscall.h b/arch/mips/include/asm/syscall.h
index 7c713025b23f..0170602a1e4e 100644
--- a/arch/mips/include/asm/syscall.h
+++ b/arch/mips/include/asm/syscall.h
@@ -26,12 +26,34 @@
 #define __NR_syscall 4000
 #endif
 
+static inline bool mips_syscall_is_indirect(struct task_struct *task,
+					    struct pt_regs *regs)
+{
+	/* O32 ABI syscall() - Either 64-bit with O32 or 32-bit */
+	return (IS_ENABLED(CONFIG_32BIT) ||
+		test_tsk_thread_flag(task, TIF_32BIT_REGS)) &&
+		(regs->regs[2] == __NR_syscall);
+}
+
 static inline long syscall_get_nr(struct task_struct *task,
 				  struct pt_regs *regs)
 {
 	return current_thread_info()->syscall;
 }
 
+static inline void mips_syscall_update_nr(struct task_struct *task,
+					  struct pt_regs *regs)
+{
+	/*
+	 * v0 is the system call number, except for O32 ABI syscall(), where it
+	 * ends up in a0.
+	 */
+	if (mips_syscall_is_indirect(task, regs))
+		task_thread_info(task)->syscall = regs->regs[4];
+	else
+		task_thread_info(task)->syscall = regs->regs[2];
+}
+
 static inline unsigned long mips_get_syscall_arg(unsigned long *arg,
 	struct task_struct *task, struct pt_regs *regs, unsigned int n)
 {
@@ -98,10 +120,9 @@ static inline void syscall_get_arguments(struct task_struct *task,
 					 unsigned long *args)
 {
 	int ret;
-	/* O32 ABI syscall() - Either 64-bit with O32 or 32-bit */
-	if ((IS_ENABLED(CONFIG_32BIT) ||
-	    test_tsk_thread_flag(task, TIF_32BIT_REGS)) &&
-	    (regs->regs[2] == __NR_syscall))
+
+	/* O32 ABI syscall() */
+	if (mips_syscall_is_indirect(task, regs))
 		i++;
 
 	while (n--)