Adding upstream version 6.1.76.upstream/6.1.76upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 341 insertions, 0 deletions

diff --git a/arch/mips/loongson64/cop2-ex.c b/arch/mips/loongson64/cop2-ex.c
new file mode 100644
index 000000000..00055d4b6
--- /dev/null
+++ b/arch/mips/loongson64/cop2-ex.c
@@ -0,0 +1,341 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2014 Lemote Corporation.
+ *   written by Huacai Chen <chenhc@lemote.com>
+ *
+ * based on arch/mips/cavium-octeon/cpu.c
+ * Copyright (C) 2009 Wind River Systems,
+ *   written by Ralf Baechle <ralf@linux-mips.org>
+ */
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/notifier.h>
+#include <linux/ptrace.h>
+#include <linux/uaccess.h>
+#include <linux/sched/signal.h>
+
+#include <asm/fpu.h>
+#include <asm/cop2.h>
+#include <asm/inst.h>
+#include <asm/branch.h>
+#include <asm/current.h>
+#include <asm/mipsregs.h>
+#include <asm/unaligned-emul.h>
+
+static int loongson_cu2_call(struct notifier_block *nfb, unsigned long action,
+	void *data)
+{
+	unsigned int res, fpu_owned;
+	unsigned long ra, value, value_next;
+	union mips_instruction insn;
+	int fr = !test_thread_flag(TIF_32BIT_FPREGS);
+	struct pt_regs *regs = (struct pt_regs *)data;
+	void __user *addr = (void __user *)regs->cp0_badvaddr;
+	unsigned int __user *pc = (unsigned int __user *)exception_epc(regs);
+
+	ra = regs->regs[31];
+	__get_user(insn.word, pc);
+
+	switch (action) {
+	case CU2_EXCEPTION:
+		preempt_disable();
+		fpu_owned = __is_fpu_owner();
+		if (!fr)
+			set_c0_status(ST0_CU1 | ST0_CU2);
+		else
+			set_c0_status(ST0_CU1 | ST0_CU2 | ST0_FR);
+		enable_fpu_hazard();
+		KSTK_STATUS(current) |= (ST0_CU1 | ST0_CU2);
+		if (fr)
+			KSTK_STATUS(current) |= ST0_FR;
+		else
+			KSTK_STATUS(current) &= ~ST0_FR;
+		/* If FPU is owned, we needn't init or restore fp */
+		if (!fpu_owned) {
+			set_thread_flag(TIF_USEDFPU);
+			init_fp_ctx(current);
+			_restore_fp(current);
+		}
+		preempt_enable();
+
+		return NOTIFY_STOP;	/* Don't call default notifier */
+
+	case CU2_LWC2_OP:
+		if (insn.loongson3_lswc2_format.ls == 0)
+			goto sigbus;
+
+		if (insn.loongson3_lswc2_format.fr == 0) {	/* gslq */
+			if (!access_ok(addr, 16))
+				goto sigbus;
+
+			LoadDW(addr, value, res);
+			if (res)
+				goto fault;
+
+			LoadDW(addr + 8, value_next, res);
+			if (res)
+				goto fault;
+
+			regs->regs[insn.loongson3_lswc2_format.rt] = value;
+			regs->regs[insn.loongson3_lswc2_format.rq] = value_next;
+			compute_return_epc(regs);
+		} else {					/* gslqc1 */
+			if (!access_ok(addr, 16))
+				goto sigbus;
+
+			lose_fpu(1);
+			LoadDW(addr, value, res);
+			if (res)
+				goto fault;
+
+			LoadDW(addr + 8, value_next, res);
+			if (res)
+				goto fault;
+
+			set_fpr64(&current->thread.fpu.fpr[insn.loongson3_lswc2_format.rt], 0, value);
+			set_fpr64(&current->thread.fpu.fpr[insn.loongson3_lswc2_format.rq], 0, value_next);
+			compute_return_epc(regs);
+			own_fpu(1);
+		}
+		return NOTIFY_STOP;	/* Don't call default notifier */
+
+	case CU2_SWC2_OP:
+		if (insn.loongson3_lswc2_format.ls == 0)
+			goto sigbus;
+
+		if (insn.loongson3_lswc2_format.fr == 0) {	/* gssq */
+			if (!access_ok(addr, 16))
+				goto sigbus;
+
+			/* write upper 8 bytes first */
+			value_next = regs->regs[insn.loongson3_lswc2_format.rq];
+
+			StoreDW(addr + 8, value_next, res);
+			if (res)
+				goto fault;
+			value = regs->regs[insn.loongson3_lswc2_format.rt];
+
+			StoreDW(addr, value, res);
+			if (res)
+				goto fault;
+
+			compute_return_epc(regs);
+		} else {					/* gssqc1 */
+			if (!access_ok(addr, 16))
+				goto sigbus;
+
+			lose_fpu(1);
+			value_next = get_fpr64(&current->thread.fpu.fpr[insn.loongson3_lswc2_format.rq], 0);
+
+			StoreDW(addr + 8, value_next, res);
+			if (res)
+				goto fault;
+
+			value = get_fpr64(&current->thread.fpu.fpr[insn.loongson3_lswc2_format.rt], 0);
+
+			StoreDW(addr, value, res);
+			if (res)
+				goto fault;
+
+			compute_return_epc(regs);
+			own_fpu(1);
+		}
+		return NOTIFY_STOP;	/* Don't call default notifier */
+
+	case CU2_LDC2_OP:
+		switch (insn.loongson3_lsdc2_format.opcode1) {
+		/*
+		 * Loongson-3 overridden ldc2 instructions.
+		 * opcode1              instruction
+		 *   0x1          gslhx: load 2 bytes to GPR
+		 *   0x2          gslwx: load 4 bytes to GPR
+		 *   0x3          gsldx: load 8 bytes to GPR
+		 *   0x6	  gslwxc1: load 4 bytes to FPR
+		 *   0x7	  gsldxc1: load 8 bytes to FPR
+		 */
+		case 0x1:
+			if (!access_ok(addr, 2))
+				goto sigbus;
+
+			LoadHW(addr, value, res);
+			if (res)
+				goto fault;
+
+			compute_return_epc(regs);
+			regs->regs[insn.loongson3_lsdc2_format.rt] = value;
+			break;
+		case 0x2:
+			if (!access_ok(addr, 4))
+				goto sigbus;
+
+			LoadW(addr, value, res);
+			if (res)
+				goto fault;
+
+			compute_return_epc(regs);
+			regs->regs[insn.loongson3_lsdc2_format.rt] = value;
+			break;
+		case 0x3:
+			if (!access_ok(addr, 8))
+				goto sigbus;
+
+			LoadDW(addr, value, res);
+			if (res)
+				goto fault;
+
+			compute_return_epc(regs);
+			regs->regs[insn.loongson3_lsdc2_format.rt] = value;
+			break;
+		case 0x6:
+			die_if_kernel("Unaligned FP access in kernel code", regs);
+			BUG_ON(!used_math());
+			if (!access_ok(addr, 4))
+				goto sigbus;
+
+			lose_fpu(1);
+			LoadW(addr, value, res);
+			if (res)
+				goto fault;
+
+			set_fpr64(&current->thread.fpu.fpr[insn.loongson3_lsdc2_format.rt], 0, value);
+			compute_return_epc(regs);
+			own_fpu(1);
+
+			break;
+		case 0x7:
+			die_if_kernel("Unaligned FP access in kernel code", regs);
+			BUG_ON(!used_math());
+			if (!access_ok(addr, 8))
+				goto sigbus;
+
+			lose_fpu(1);
+			LoadDW(addr, value, res);
+			if (res)
+				goto fault;
+
+			set_fpr64(&current->thread.fpu.fpr[insn.loongson3_lsdc2_format.rt], 0, value);
+			compute_return_epc(regs);
+			own_fpu(1);
+			break;
+
+		}
+		return NOTIFY_STOP;	/* Don't call default notifier */
+
+	case CU2_SDC2_OP:
+		switch (insn.loongson3_lsdc2_format.opcode1) {
+		/*
+		 * Loongson-3 overridden sdc2 instructions.
+		 * opcode1              instruction
+		 *   0x1          gsshx: store 2 bytes from GPR
+		 *   0x2          gsswx: store 4 bytes from GPR
+		 *   0x3          gssdx: store 8 bytes from GPR
+		 *   0x6          gsswxc1: store 4 bytes from FPR
+		 *   0x7          gssdxc1: store 8 bytes from FPR
+		 */
+		case 0x1:
+			if (!access_ok(addr, 2))
+				goto sigbus;
+
+			compute_return_epc(regs);
+			value = regs->regs[insn.loongson3_lsdc2_format.rt];
+
+			StoreHW(addr, value, res);
+			if (res)
+				goto fault;
+
+			break;
+		case 0x2:
+			if (!access_ok(addr, 4))
+				goto sigbus;
+
+			compute_return_epc(regs);
+			value = regs->regs[insn.loongson3_lsdc2_format.rt];
+
+			StoreW(addr, value, res);
+			if (res)
+				goto fault;
+
+			break;
+		case 0x3:
+			if (!access_ok(addr, 8))
+				goto sigbus;
+
+			compute_return_epc(regs);
+			value = regs->regs[insn.loongson3_lsdc2_format.rt];
+
+			StoreDW(addr, value, res);
+			if (res)
+				goto fault;
+
+			break;
+
+		case 0x6:
+			die_if_kernel("Unaligned FP access in kernel code", regs);
+			BUG_ON(!used_math());
+
+			if (!access_ok(addr, 4))
+				goto sigbus;
+
+			lose_fpu(1);
+			value = get_fpr64(&current->thread.fpu.fpr[insn.loongson3_lsdc2_format.rt], 0);
+
+			StoreW(addr, value, res);
+			if (res)
+				goto fault;
+
+			compute_return_epc(regs);
+			own_fpu(1);
+
+			break;
+		case 0x7:
+			die_if_kernel("Unaligned FP access in kernel code", regs);
+			BUG_ON(!used_math());
+
+			if (!access_ok(addr, 8))
+				goto sigbus;
+
+			lose_fpu(1);
+			value = get_fpr64(&current->thread.fpu.fpr[insn.loongson3_lsdc2_format.rt], 0);
+
+			StoreDW(addr, value, res);
+			if (res)
+				goto fault;
+
+			compute_return_epc(regs);
+			own_fpu(1);
+
+			break;
+		}
+		return NOTIFY_STOP;	/* Don't call default notifier */
+	}
+
+	return NOTIFY_OK;		/* Let default notifier send signals */
+
+fault:
+	/* roll back jump/branch */
+	regs->regs[31] = ra;
+	regs->cp0_epc = (unsigned long)pc;
+	/* Did we have an exception handler installed? */
+	if (fixup_exception(regs))
+		return NOTIFY_STOP;	/* Don't call default notifier */
+
+	die_if_kernel("Unhandled kernel unaligned access", regs);
+	force_sig(SIGSEGV);
+
+	return NOTIFY_STOP;	/* Don't call default notifier */
+
+sigbus:
+	die_if_kernel("Unhandled kernel unaligned access", regs);
+	force_sig(SIGBUS);
+
+	return NOTIFY_STOP;	/* Don't call default notifier */
+}
+
+static int __init loongson_cu2_setup(void)
+{
+	return cu2_notifier(loongson_cu2_call, 0);
+}
+early_initcall(loongson_cu2_setup);