Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus

Pull MIPS updates from Ralf Baechle:

 - More work on DT support for various platforms

 - Various fixes that were to late to make it straight into 3.9

 - Improved platform support, in particular the Netlogic XLR and
   BCM63xx, and the SEAD3 and Malta eval boards.

 - Support for several Ralink SOC families.

 - Complete support for the microMIPS ASE which basically reencodes the
   existing MIPS32/MIPS64 ISA to use non-constant size instructions.

 - Some fallout from LTO work which remove old cruft and will generally
   make the MIPS kernel easier to maintain and resistant to compiler
   optimization, even in absence of LTO.

 - KVM support.  While MIPS has announced hardware virtualization
   extensions this KVM extension uses trap and emulate mode for
   virtualization of MIPS32.  More KVM work to add support for VZ
   hardware virtualizaiton extensions and MIPS64 will probably already
   be merged for 3.11.

Most of this has been sitting in -next for a long time.  All defconfigs
have been build or run time tested except three for which fixes are being
sent by other maintainers.

Semantic conflict with kvm updates done as per Ralf

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (118 commits)
  MIPS: Add new GIC clockevent driver.
  MIPS: Formatting clean-ups for clocksources.
  MIPS: Refactor GIC clocksource code.
  MIPS: Move 'gic_frequency' to common location.
  MIPS: Move 'gic_present' to common location.
  MIPS: MIPS16e: Add unaligned access support.
  MIPS: MIPS16e: Support handling of delay slots.
  MIPS: MIPS16e: Add instruction formats.
  MIPS: microMIPS: Optimise 'strnlen' core library function.
  MIPS: microMIPS: Optimise 'strlen' core library function.
  MIPS: microMIPS: Optimise 'strncpy' core library function.
  MIPS: microMIPS: Optimise 'memset' core library function.
  MIPS: microMIPS: Add configuration option for microMIPS kernel.
  MIPS: microMIPS: Disable LL/SC and fix linker bug.
  MIPS: microMIPS: Add vdso support.
  MIPS: microMIPS: Add unaligned access support.
  MIPS: microMIPS: Support handling of delay slots.
  MIPS: microMIPS: Add support for exception handling.
  MIPS: microMIPS: Floating point support.
  MIPS: microMIPS: Fix macro naming in micro-assembler.
  ...

1 files changed, 178 insertions, 0 deletions

diff --git a/arch/mips/kernel/branch.c b/arch/mips/kernel/branch.c
index 83ffe950f710..46c2ad0703a0 100644
--- a/arch/mips/kernel/branch.c
+++ b/arch/mips/kernel/branch.c
@@ -14,10 +14,186 @@
 #include <asm/cpu.h>
 #include <asm/cpu-features.h>
 #include <asm/fpu.h>
+#include <asm/fpu_emulator.h>
 #include <asm/inst.h>
 #include <asm/ptrace.h>
 #include <asm/uaccess.h>
 
+/*
+ * Calculate and return exception PC in case of branch delay slot
+ * for microMIPS and MIPS16e. It does not clear the ISA mode bit.
+ */
+int __isa_exception_epc(struct pt_regs *regs)
+{
+	unsigned short inst;
+	long epc = regs->cp0_epc;
+
+	/* Calculate exception PC in branch delay slot. */
+	if (__get_user(inst, (u16 __user *) msk_isa16_mode(epc))) {
+		/* This should never happen because delay slot was checked. */
+		force_sig(SIGSEGV, current);
+		return epc;
+	}
+	if (cpu_has_mips16) {
+		if (((union mips16e_instruction)inst).ri.opcode
+				== MIPS16e_jal_op)
+			epc += 4;
+		else
+			epc += 2;
+	} else if (mm_insn_16bit(inst))
+		epc += 2;
+	else
+		epc += 4;
+
+	return epc;
+}
+
+/*
+ * Compute return address and emulate branch in microMIPS mode after an
+ * exception only. It does not handle compact branches/jumps and cannot
+ * be used in interrupt context. (Compact branches/jumps do not cause
+ * exceptions.)
+ */
+int __microMIPS_compute_return_epc(struct pt_regs *regs)
+{
+	u16 __user *pc16;
+	u16 halfword;
+	unsigned int word;
+	unsigned long contpc;
+	struct mm_decoded_insn mminsn = { 0 };
+
+	mminsn.micro_mips_mode = 1;
+
+	/* This load never faults. */
+	pc16 = (unsigned short __user *)msk_isa16_mode(regs->cp0_epc);
+	__get_user(halfword, pc16);
+	pc16++;
+	contpc = regs->cp0_epc + 2;
+	word = ((unsigned int)halfword << 16);
+	mminsn.pc_inc = 2;
+
+	if (!mm_insn_16bit(halfword)) {
+		__get_user(halfword, pc16);
+		pc16++;
+		contpc = regs->cp0_epc + 4;
+		mminsn.pc_inc = 4;
+		word |= halfword;
+	}
+	mminsn.insn = word;
+
+	if (get_user(halfword, pc16))
+		goto sigsegv;
+	mminsn.next_pc_inc = 2;
+	word = ((unsigned int)halfword << 16);
+
+	if (!mm_insn_16bit(halfword)) {
+		pc16++;
+		if (get_user(halfword, pc16))
+			goto sigsegv;
+		mminsn.next_pc_inc = 4;
+		word |= halfword;
+	}
+	mminsn.next_insn = word;
+
+	mm_isBranchInstr(regs, mminsn, &contpc);
+
+	regs->cp0_epc = contpc;
+
+	return 0;
+
+sigsegv:
+	force_sig(SIGSEGV, current);
+	return -EFAULT;
+}
+
+/*
+ * Compute return address and emulate branch in MIPS16e mode after an
+ * exception only. It does not handle compact branches/jumps and cannot
+ * be used in interrupt context. (Compact branches/jumps do not cause
+ * exceptions.)
+ */
+int __MIPS16e_compute_return_epc(struct pt_regs *regs)
+{
+	u16 __user *addr;
+	union mips16e_instruction inst;
+	u16 inst2;
+	u32 fullinst;
+	long epc;
+
+	epc = regs->cp0_epc;
+
+	/* Read the instruction. */
+	addr = (u16 __user *)msk_isa16_mode(epc);
+	if (__get_user(inst.full, addr)) {
+		force_sig(SIGSEGV, current);
+		return -EFAULT;
+	}
+
+	switch (inst.ri.opcode) {
+	case MIPS16e_extend_op:
+		regs->cp0_epc += 4;
+		return 0;
+
+		/*
+		 *  JAL and JALX in MIPS16e mode
+		 */
+	case MIPS16e_jal_op:
+		addr += 1;
+		if (__get_user(inst2, addr)) {
+			force_sig(SIGSEGV, current);
+			return -EFAULT;
+		}
+		fullinst = ((unsigned)inst.full << 16) | inst2;
+		regs->regs[31] = epc + 6;
+		epc += 4;
+		epc >>= 28;
+		epc <<= 28;
+		/*
+		 * JAL:5 X:1 TARGET[20-16]:5 TARGET[25:21]:5 TARGET[15:0]:16
+		 *
+		 * ......TARGET[15:0].................TARGET[20:16]...........
+		 * ......TARGET[25:21]
+		 */
+		epc |=
+		    ((fullinst & 0xffff) << 2) | ((fullinst & 0x3e00000) >> 3) |
+		    ((fullinst & 0x1f0000) << 7);
+		if (!inst.jal.x)
+			set_isa16_mode(epc);	/* Set ISA mode bit. */
+		regs->cp0_epc = epc;
+		return 0;
+
+		/*
+		 *  J(AL)R(C)
+		 */
+	case MIPS16e_rr_op:
+		if (inst.rr.func == MIPS16e_jr_func) {
+
+			if (inst.rr.ra)
+				regs->cp0_epc = regs->regs[31];
+			else
+				regs->cp0_epc =
+				    regs->regs[reg16to32[inst.rr.rx]];
+
+			if (inst.rr.l) {
+				if (inst.rr.nd)
+					regs->regs[31] = epc + 2;
+				else
+					regs->regs[31] = epc + 4;
+			}
+			return 0;
+		}
+		break;
+	}
+
+	/*
+	 * All other cases have no branch delay slot and are 16-bits.
+	 * Branches do not cause an exception.
+	 */
+	regs->cp0_epc += 2;
+
+	return 0;
+}
+
 /**
  * __compute_return_epc_for_insn - Computes the return address and do emulate
  *				    branch simulation, if required.
@@ -129,6 +305,8 @@ int __compute_return_epc_for_insn(struct pt_regs *regs,
 		epc <<= 28;
 		epc |= (insn.j_format.target << 2);
 		regs->cp0_epc = epc;
+		if (insn.i_format.opcode == jalx_op)
+			set_isa16_mode(regs->cp0_epc);
 		break;
 
 	/*