Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/csky/kernel/traps.c b/arch/csky/kernel/traps.c
new file mode 100644
index 0000000..b057480
--- /dev/null
+++ b/arch/csky/kernel/traps.c
@@ -0,0 +1,168 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#include <linux/sched.h>
+#include <linux/signal.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/user.h>
+#include <linux/string.h>
+#include <linux/linkage.h>
+#include <linux/init.h>
+#include <linux/ptrace.h>
+#include <linux/kallsyms.h>
+#include <linux/rtc.h>
+#include <linux/uaccess.h>
+
+#include <asm/setup.h>
+#include <asm/traps.h>
+#include <asm/pgalloc.h>
+#include <asm/siginfo.h>
+
+#include <asm/mmu_context.h>
+
+#ifdef CONFIG_CPU_HAS_FPU
+#include <abi/fpu.h>
+#endif
+
+/* Defined in entry.S */
+asmlinkage void csky_trap(void);
+
+asmlinkage void csky_systemcall(void);
+asmlinkage void csky_cmpxchg(void);
+asmlinkage void csky_get_tls(void);
+asmlinkage void csky_irq(void);
+
+asmlinkage void csky_tlbinvalidl(void);
+asmlinkage void csky_tlbinvalids(void);
+asmlinkage void csky_tlbmodified(void);
+
+/* Defined in head.S */
+asmlinkage void _start_smp_secondary(void);
+
+void __init pre_trap_init(void)
+{
+ int i;
+
+ mtcr("vbr", vec_base);
+
+ for (i = 1; i < 128; i++)
+ VEC_INIT(i, csky_trap);
+}
+
+void __init trap_init(void)
+{
+ VEC_INIT(VEC_AUTOVEC, csky_irq);
+
+ /* setup trap0 trap2 trap3 */
+ VEC_INIT(VEC_TRAP0, csky_systemcall);
+ VEC_INIT(VEC_TRAP2, csky_cmpxchg);
+ VEC_INIT(VEC_TRAP3, csky_get_tls);
+
+ /* setup MMU TLB exception */
+ VEC_INIT(VEC_TLBINVALIDL, csky_tlbinvalidl);
+ VEC_INIT(VEC_TLBINVALIDS, csky_tlbinvalids);
+ VEC_INIT(VEC_TLBMODIFIED, csky_tlbmodified);
+
+#ifdef CONFIG_CPU_HAS_FPU
+ init_fpu();
+#endif
+
+#ifdef CONFIG_SMP
+ mtcr("cr<28, 0>", virt_to_phys(vec_base));
+
+ VEC_INIT(VEC_RESET, (void *)virt_to_phys(_start_smp_secondary));
+#endif
+}
+
+void die_if_kernel(char *str, struct pt_regs *regs, int nr)
+{
+ if (user_mode(regs))
+ return;
+
+ console_verbose();
+ pr_err("%s: %08x\n", str, nr);
+ show_regs(regs);
+ add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
+ do_exit(SIGSEGV);
+}
+
+void buserr(struct pt_regs *regs)
+{
+#ifdef CONFIG_CPU_CK810
+ static unsigned long prev_pc;
+
+ if ((regs->pc == prev_pc) && prev_pc != 0) {
+ prev_pc = 0;
+ } else {
+ prev_pc = regs->pc;
+ return;
+ }
+#endif
+
+ die_if_kernel("Kernel mode BUS error", regs, 0);
+
+ pr_err("User mode Bus Error\n");
+ show_regs(regs);
+
+ force_sig_fault(SIGSEGV, 0, (void __user *)regs->pc);
+}
+
+#define USR_BKPT 0x1464
+asmlinkage void trap_c(struct pt_regs *regs)
+{
+ int sig;
+ unsigned long vector;
+ siginfo_t info;
+
+ vector = (mfcr("psr") >> 16) & 0xff;
+
+ switch (vector) {
+ case VEC_ZERODIV:
+ die_if_kernel("Kernel mode ZERO DIV", regs, vector);
+ sig = SIGFPE;
+ break;
+ /* ptrace */
+ case VEC_TRACE:
+ info.si_code = TRAP_TRACE;
+ sig = SIGTRAP;
+ break;
+ case VEC_ILLEGAL:
+ die_if_kernel("Kernel mode ILLEGAL", regs, vector);
+#ifndef CONFIG_CPU_NO_USER_BKPT
+ if (*(uint16_t *)instruction_pointer(regs) != USR_BKPT)
+#endif
+ {
+ sig = SIGILL;
+ break;
+ }
+ /* gdbserver breakpoint */
+ case VEC_TRAP1:
+ /* jtagserver breakpoint */
+ case VEC_BREAKPOINT:
+ die_if_kernel("Kernel mode BKPT", regs, vector);
+ info.si_code = TRAP_BRKPT;
+ sig = SIGTRAP;
+ break;
+ case VEC_ACCESS:
+ return buserr(regs);
+#ifdef CONFIG_CPU_NEED_SOFTALIGN
+ case VEC_ALIGN:
+ return csky_alignment(regs);
+#endif
+#ifdef CONFIG_CPU_HAS_FPU
+ case VEC_FPE:
+ die_if_kernel("Kernel mode FPE", regs, vector);
+ return fpu_fpe(regs);
+ case VEC_PRIV:
+ die_if_kernel("Kernel mode PRIV", regs, vector);
+ if (fpu_libc_helper(regs))
+ return;
+#endif
+ default:
+ sig = SIGSEGV;
+ break;
+ }
+ send_sig(sig, current, 0);
+}