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

Pull MIPS updates from Ralf Baechle:
 - Support for Imgtec's Aptiv family of MIPS cores.
 - Improved detection of BCM47xx configurations.
 - Fix hiberation for certain configurations.
 - Add support for the Chinese Loongson 3 CPU, a MIPS64 R2 core and
   systems.
 - Detection and support for the MIPS P5600 core.
 - A few more random fixes that didn't make 3.14.
 - Support for the EVA Extended Virtual Addressing
 - Switch Alchemy to the platform PATA driver
 - Complete unification of Alchemy support
 - Allow availability of I/O cache coherency to be runtime detected
 - Improvments to multiprocessing support for Imgtec platforms
 - A few microoptimizations
 - Cleanups of FPU support
 - Paul Gortmaker's fixes for the init stuff
 - Support for seccomp

* 'mips-for-linux-next' of git://git.linux-mips.org/pub/scm/ralf/upstream-sfr: (165 commits)
  MIPS: CPC: Use __raw_ memory access functions
  MIPS: CM: use __raw_ memory access functions
  MIPS: Fix warning when including smp-ops.h with CONFIG_SMP=n
  MIPS: Malta: GIC IPIs may be used without MT
  MIPS: smp-mt: Use common GIC IPI implementation
  MIPS: smp-cmp: Remove incorrect core number probe
  MIPS: Fix gigaton of warning building with microMIPS.
  MIPS: Fix core number detection for MT cores
  MIPS: MT: core_nvpes function to retrieve VPE count
  MIPS: Provide empty mips_mt_set_cpuoptions when CONFIG_MIPS_MT=n
  MIPS: Lasat: Replace del_timer by del_timer_sync
  MIPS: Malta: Setup PM I/O region on boot
  MIPS: Loongson: Add a Loongson-3 default config file
  MIPS: Loongson 3: Add CPU hotplug support
  MIPS: Loongson 3: Add Loongson-3 SMP support
  MIPS: Loongson: Add Loongson-3 Kconfig options
  MIPS: Loongson: Add swiotlb to support All-Memory DMA
  MIPS: Loongson 3: Add serial port support
  MIPS: Loongson 3: Add IRQ init and dispatch support
  MIPS: Loongson 3: Add HT-linked PCI support
  ...

1 files changed, 148 insertions, 22 deletions

diff --git a/arch/mips/kernel/signal.c b/arch/mips/kernel/signal.c
index 5199563c4403..33133d3df3e5 100644
--- a/arch/mips/kernel/signal.c
+++ b/arch/mips/kernel/signal.c
@@ -6,6 +6,7 @@
  * Copyright (C) 1991, 1992  Linus Torvalds
  * Copyright (C) 1994 - 2000  Ralf Baechle
  * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
+ * Copyright (C) 2014, Imagination Technologies Ltd.
  */
 #include <linux/cache.h>
 #include <linux/context_tracking.h>
@@ -30,6 +31,7 @@
 #include <linux/bitops.h>
 #include <asm/cacheflush.h>
 #include <asm/fpu.h>
+#include <asm/msa.h>
 #include <asm/sim.h>
 #include <asm/ucontext.h>
 #include <asm/cpu-features.h>
@@ -46,8 +48,8 @@ static int (*restore_fp_context)(struct sigcontext __user *sc);
 extern asmlinkage int _save_fp_context(struct sigcontext __user *sc);
 extern asmlinkage int _restore_fp_context(struct sigcontext __user *sc);
 
-extern asmlinkage int fpu_emulator_save_context(struct sigcontext __user *sc);
-extern asmlinkage int fpu_emulator_restore_context(struct sigcontext __user *sc);
+extern asmlinkage int _save_msa_context(struct sigcontext __user *sc);
+extern asmlinkage int _restore_msa_context(struct sigcontext __user *sc);
 
 struct sigframe {
 	u32 sf_ass[4];		/* argument save space for o32 */
@@ -64,17 +66,95 @@ struct rt_sigframe {
 };
 
 /*
+ * Thread saved context copy to/from a signal context presumed to be on the
+ * user stack, and therefore accessed with appropriate macros from uaccess.h.
+ */
+static int copy_fp_to_sigcontext(struct sigcontext __user *sc)
+{
+	int i;
+	int err = 0;
+
+	for (i = 0; i < NUM_FPU_REGS; i++) {
+		err |=
+		    __put_user(get_fpr64(&current->thread.fpu.fpr[i], 0),
+			       &sc->sc_fpregs[i]);
+	}
+	err |= __put_user(current->thread.fpu.fcr31, &sc->sc_fpc_csr);
+
+	return err;
+}
+
+static int copy_fp_from_sigcontext(struct sigcontext __user *sc)
+{
+	int i;
+	int err = 0;
+	u64 fpr_val;
+
+	for (i = 0; i < NUM_FPU_REGS; i++) {
+		err |= __get_user(fpr_val, &sc->sc_fpregs[i]);
+		set_fpr64(&current->thread.fpu.fpr[i], 0, fpr_val);
+	}
+	err |= __get_user(current->thread.fpu.fcr31, &sc->sc_fpc_csr);
+
+	return err;
+}
+
+/*
+ * These functions will save only the upper 64 bits of the vector registers,
+ * since the lower 64 bits have already been saved as the scalar FP context.
+ */
+static int copy_msa_to_sigcontext(struct sigcontext __user *sc)
+{
+	int i;
+	int err = 0;
+
+	for (i = 0; i < NUM_FPU_REGS; i++) {
+		err |=
+		    __put_user(get_fpr64(&current->thread.fpu.fpr[i], 1),
+			       &sc->sc_msaregs[i]);
+	}
+	err |= __put_user(current->thread.fpu.msacsr, &sc->sc_msa_csr);
+
+	return err;
+}
+
+static int copy_msa_from_sigcontext(struct sigcontext __user *sc)
+{
+	int i;
+	int err = 0;
+	u64 val;
+
+	for (i = 0; i < NUM_FPU_REGS; i++) {
+		err |= __get_user(val, &sc->sc_msaregs[i]);
+		set_fpr64(&current->thread.fpu.fpr[i], 1, val);
+	}
+	err |= __get_user(current->thread.fpu.msacsr, &sc->sc_msa_csr);
+
+	return err;
+}
+
+/*
  * Helper routines
  */
-static int protected_save_fp_context(struct sigcontext __user *sc)
+static int protected_save_fp_context(struct sigcontext __user *sc,
+				     unsigned used_math)
 {
 	int err;
+	bool save_msa = cpu_has_msa && (used_math & USEDMATH_MSA);
+#ifndef CONFIG_EVA
 	while (1) {
 		lock_fpu_owner();
-		err = own_fpu_inatomic(1);
-		if (!err)
-			err = save_fp_context(sc); /* this might fail */
-		unlock_fpu_owner();
+		if (is_fpu_owner()) {
+			err = save_fp_context(sc);
+			if (save_msa && !err)
+				err = _save_msa_context(sc);
+			unlock_fpu_owner();
+		} else {
+			unlock_fpu_owner();
+			err = copy_fp_to_sigcontext(sc);
+			if (save_msa && !err)
+				err = copy_msa_to_sigcontext(sc);
+		}
 		if (likely(!err))
 			break;
 		/* touch the sigcontext and try again */
@@ -84,18 +164,44 @@ static int protected_save_fp_context(struct sigcontext __user *sc)
 		if (err)
 			break;	/* really bad sigcontext */
 	}
+#else
+	/*
+	 * EVA does not have FPU EVA instructions so saving fpu context directly
+	 * does not work.
+	 */
+	disable_msa();
+	lose_fpu(1);
+	err = save_fp_context(sc); /* this might fail */
+	if (save_msa && !err)
+		err = copy_msa_to_sigcontext(sc);
+#endif
 	return err;
 }
 
-static int protected_restore_fp_context(struct sigcontext __user *sc)
+static int protected_restore_fp_context(struct sigcontext __user *sc,
+					unsigned used_math)
 {
 	int err, tmp __maybe_unused;
+	bool restore_msa = cpu_has_msa && (used_math & USEDMATH_MSA);
+#ifndef CONFIG_EVA
 	while (1) {
 		lock_fpu_owner();
-		err = own_fpu_inatomic(0);
-		if (!err)
-			err = restore_fp_context(sc); /* this might fail */
-		unlock_fpu_owner();
+		if (is_fpu_owner()) {
+			err = restore_fp_context(sc);
+			if (restore_msa && !err) {
+				enable_msa();
+				err = _restore_msa_context(sc);
+			} else {
+				/* signal handler may have used MSA */
+				disable_msa();
+			}
+			unlock_fpu_owner();
+		} else {
+			unlock_fpu_owner();
+			err = copy_fp_from_sigcontext(sc);
+			if (!err && (used_math & USEDMATH_MSA))
+				err = copy_msa_from_sigcontext(sc);
+		}
 		if (likely(!err))
 			break;
 		/* touch the sigcontext and try again */
@@ -105,6 +211,17 @@ static int protected_restore_fp_context(struct sigcontext __user *sc)
 		if (err)
 			break;	/* really bad sigcontext */
 	}
+#else
+	/*
+	 * EVA does not have FPU EVA instructions so restoring fpu context
+	 * directly does not work.
+	 */
+	enable_msa();
+	lose_fpu(0);
+	err = restore_fp_context(sc); /* this might fail */
+	if (restore_msa && !err)
+		err = copy_msa_from_sigcontext(sc);
+#endif
 	return err;
 }
 
@@ -135,7 +252,8 @@ int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
 		err |= __put_user(rddsp(DSP_MASK), &sc->sc_dsp);
 	}
 
-	used_math = !!used_math();
+	used_math = used_math() ? USEDMATH_FP : 0;
+	used_math |= thread_msa_context_live() ? USEDMATH_MSA : 0;
 	err |= __put_user(used_math, &sc->sc_used_math);
 
 	if (used_math) {
@@ -143,7 +261,7 @@ int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
 		 * Save FPU state to signal context. Signal handler
 		 * will "inherit" current FPU state.
 		 */
-		err |= protected_save_fp_context(sc);
+		err |= protected_save_fp_context(sc, used_math);
 	}
 	return err;
 }
@@ -168,14 +286,14 @@ int fpcsr_pending(unsigned int __user *fpcsr)
 }
 
 static int
-check_and_restore_fp_context(struct sigcontext __user *sc)
+check_and_restore_fp_context(struct sigcontext __user *sc, unsigned used_math)
 {
 	int err, sig;
 
 	err = sig = fpcsr_pending(&sc->sc_fpc_csr);
 	if (err > 0)
 		err = 0;
-	err |= protected_restore_fp_context(sc);
+	err |= protected_restore_fp_context(sc, used_math);
 	return err ?: sig;
 }
 
@@ -215,9 +333,10 @@ int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
 	if (used_math) {
 		/* restore fpu context if we have used it before */
 		if (!err)
-			err = check_and_restore_fp_context(sc);
+			err = check_and_restore_fp_context(sc, used_math);
 	} else {
-		/* signal handler may have used FPU.  Give it up. */
+		/* signal handler may have used FPU or MSA. Disable them. */
+		disable_msa();
 		lose_fpu(0);
 	}
 
@@ -591,23 +710,26 @@ asmlinkage void do_notify_resume(struct pt_regs *regs, void *unused,
 }
 
 #ifdef CONFIG_SMP
+#ifndef CONFIG_EVA
 static int smp_save_fp_context(struct sigcontext __user *sc)
 {
 	return raw_cpu_has_fpu
 	       ? _save_fp_context(sc)
-	       : fpu_emulator_save_context(sc);
+	       : copy_fp_to_sigcontext(sc);
 }
 
 static int smp_restore_fp_context(struct sigcontext __user *sc)
 {
 	return raw_cpu_has_fpu
 	       ? _restore_fp_context(sc)
-	       : fpu_emulator_restore_context(sc);
+	       : copy_fp_from_sigcontext(sc);
 }
+#endif /* CONFIG_EVA */
 #endif
 
 static int signal_setup(void)
 {
+#ifndef CONFIG_EVA
 #ifdef CONFIG_SMP
 	/* For now just do the cpu_has_fpu check when the functions are invoked */
 	save_fp_context = smp_save_fp_context;
@@ -617,9 +739,13 @@ static int signal_setup(void)
 		save_fp_context = _save_fp_context;
 		restore_fp_context = _restore_fp_context;
 	} else {
-		save_fp_context = fpu_emulator_save_context;
-		restore_fp_context = fpu_emulator_restore_context;
+		save_fp_context = copy_fp_from_sigcontext;
+		restore_fp_context = copy_fp_to_sigcontext;
 	}
+#endif /* CONFIG_SMP */
+#else
+	save_fp_context = copy_fp_from_sigcontext;;
+	restore_fp_context = copy_fp_to_sigcontext;
 #endif
 
 	return 0;