v4.19.13 snapshot.
diff --git a/arch/sparc/kernel/process_32.c b/arch/sparc/kernel/process_32.c
new file mode 100644
index 0000000..d9662cf
--- /dev/null
+++ b/arch/sparc/kernel/process_32.c
@@ -0,0 +1,491 @@
+// SPDX-License-Identifier: GPL-2.0
+/* linux/arch/sparc/kernel/process.c
+ *
+ * Copyright (C) 1995, 2008 David S. Miller (davem@davemloft.net)
+ * Copyright (C) 1996 Eddie C. Dost (ecd@skynet.be)
+ */
+
+/*
+ * This file handles the architecture-dependent parts of process handling..
+ */
+
+#include <stdarg.h>
+
+#include <linux/elfcore.h>
+#include <linux/errno.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/sched/debug.h>
+#include <linux/sched/task.h>
+#include <linux/sched/task_stack.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/stddef.h>
+#include <linux/ptrace.h>
+#include <linux/user.h>
+#include <linux/smp.h>
+#include <linux/reboot.h>
+#include <linux/delay.h>
+#include <linux/pm.h>
+#include <linux/slab.h>
+#include <linux/cpu.h>
+
+#include <asm/auxio.h>
+#include <asm/oplib.h>
+#include <linux/uaccess.h>
+#include <asm/page.h>
+#include <asm/pgalloc.h>
+#include <asm/pgtable.h>
+#include <asm/delay.h>
+#include <asm/processor.h>
+#include <asm/psr.h>
+#include <asm/elf.h>
+#include <asm/prom.h>
+#include <asm/unistd.h>
+#include <asm/setup.h>
+
+#include "kernel.h"
+
+/*
+ * Power management idle function
+ * Set in pm platform drivers (apc.c and pmc.c)
+ */
+void (*sparc_idle)(void);
+
+/*
+ * Power-off handler instantiation for pm.h compliance
+ * This is done via auxio, but could be used as a fallback
+ * handler when auxio is not present-- unused for now...
+ */
+void (*pm_power_off)(void) = machine_power_off;
+EXPORT_SYMBOL(pm_power_off);
+
+/*
+ * sysctl - toggle power-off restriction for serial console
+ * systems in machine_power_off()
+ */
+int scons_pwroff = 1;
+
+extern void fpsave(unsigned long *, unsigned long *, void *, unsigned long *);
+
+struct task_struct *last_task_used_math = NULL;
+struct thread_info *current_set[NR_CPUS];
+
+/* Idle loop support. */
+void arch_cpu_idle(void)
+{
+ if (sparc_idle)
+ (*sparc_idle)();
+ local_irq_enable();
+}
+
+/* XXX cli/sti -> local_irq_xxx here, check this works once SMP is fixed. */
+void machine_halt(void)
+{
+ local_irq_enable();
+ mdelay(8);
+ local_irq_disable();
+ prom_halt();
+ panic("Halt failed!");
+}
+
+void machine_restart(char * cmd)
+{
+ char *p;
+
+ local_irq_enable();
+ mdelay(8);
+ local_irq_disable();
+
+ p = strchr (reboot_command, '\n');
+ if (p) *p = 0;
+ if (cmd)
+ prom_reboot(cmd);
+ if (*reboot_command)
+ prom_reboot(reboot_command);
+ prom_feval ("reset");
+ panic("Reboot failed!");
+}
+
+void machine_power_off(void)
+{
+ if (auxio_power_register &&
+ (strcmp(of_console_device->type, "serial") || scons_pwroff)) {
+ u8 power_register = sbus_readb(auxio_power_register);
+ power_register |= AUXIO_POWER_OFF;
+ sbus_writeb(power_register, auxio_power_register);
+ }
+
+ machine_halt();
+}
+
+void show_regs(struct pt_regs *r)
+{
+ struct reg_window32 *rw = (struct reg_window32 *) r->u_regs[14];
+
+ show_regs_print_info(KERN_DEFAULT);
+
+ printk("PSR: %08lx PC: %08lx NPC: %08lx Y: %08lx %s\n",
+ r->psr, r->pc, r->npc, r->y, print_tainted());
+ printk("PC: <%pS>\n", (void *) r->pc);
+ printk("%%G: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
+ r->u_regs[0], r->u_regs[1], r->u_regs[2], r->u_regs[3],
+ r->u_regs[4], r->u_regs[5], r->u_regs[6], r->u_regs[7]);
+ printk("%%O: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
+ r->u_regs[8], r->u_regs[9], r->u_regs[10], r->u_regs[11],
+ r->u_regs[12], r->u_regs[13], r->u_regs[14], r->u_regs[15]);
+ printk("RPC: <%pS>\n", (void *) r->u_regs[15]);
+
+ printk("%%L: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
+ rw->locals[0], rw->locals[1], rw->locals[2], rw->locals[3],
+ rw->locals[4], rw->locals[5], rw->locals[6], rw->locals[7]);
+ printk("%%I: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
+ rw->ins[0], rw->ins[1], rw->ins[2], rw->ins[3],
+ rw->ins[4], rw->ins[5], rw->ins[6], rw->ins[7]);
+}
+
+/*
+ * The show_stack is an external API which we do not use ourselves.
+ * The oops is printed in die_if_kernel.
+ */
+void show_stack(struct task_struct *tsk, unsigned long *_ksp)
+{
+ unsigned long pc, fp;
+ unsigned long task_base;
+ struct reg_window32 *rw;
+ int count = 0;
+
+ if (!tsk)
+ tsk = current;
+
+ if (tsk == current && !_ksp)
+ __asm__ __volatile__("mov %%fp, %0" : "=r" (_ksp));
+
+ task_base = (unsigned long) task_stack_page(tsk);
+ fp = (unsigned long) _ksp;
+ do {
+ /* Bogus frame pointer? */
+ if (fp < (task_base + sizeof(struct thread_info)) ||
+ fp >= (task_base + (PAGE_SIZE << 1)))
+ break;
+ rw = (struct reg_window32 *) fp;
+ pc = rw->ins[7];
+ printk("[%08lx : ", pc);
+ printk("%pS ] ", (void *) pc);
+ fp = rw->ins[6];
+ } while (++count < 16);
+ printk("\n");
+}
+
+/*
+ * Free current thread data structures etc..
+ */
+void exit_thread(struct task_struct *tsk)
+{
+#ifndef CONFIG_SMP
+ if (last_task_used_math == tsk) {
+#else
+ if (test_ti_thread_flag(task_thread_info(tsk), TIF_USEDFPU)) {
+#endif
+ /* Keep process from leaving FPU in a bogon state. */
+ put_psr(get_psr() | PSR_EF);
+ fpsave(&tsk->thread.float_regs[0], &tsk->thread.fsr,
+ &tsk->thread.fpqueue[0], &tsk->thread.fpqdepth);
+#ifndef CONFIG_SMP
+ last_task_used_math = NULL;
+#else
+ clear_ti_thread_flag(task_thread_info(tsk), TIF_USEDFPU);
+#endif
+ }
+}
+
+void flush_thread(void)
+{
+ current_thread_info()->w_saved = 0;
+
+#ifndef CONFIG_SMP
+ if(last_task_used_math == current) {
+#else
+ if (test_thread_flag(TIF_USEDFPU)) {
+#endif
+ /* Clean the fpu. */
+ put_psr(get_psr() | PSR_EF);
+ fpsave(¤t->thread.float_regs[0], ¤t->thread.fsr,
+ ¤t->thread.fpqueue[0], ¤t->thread.fpqdepth);
+#ifndef CONFIG_SMP
+ last_task_used_math = NULL;
+#else
+ clear_thread_flag(TIF_USEDFPU);
+#endif
+ }
+
+ /* This task is no longer a kernel thread. */
+ if (current->thread.flags & SPARC_FLAG_KTHREAD) {
+ current->thread.flags &= ~SPARC_FLAG_KTHREAD;
+
+ /* We must fixup kregs as well. */
+ /* XXX This was not fixed for ti for a while, worked. Unused? */
+ current->thread.kregs = (struct pt_regs *)
+ (task_stack_page(current) + (THREAD_SIZE - TRACEREG_SZ));
+ }
+}
+
+static inline struct sparc_stackf __user *
+clone_stackframe(struct sparc_stackf __user *dst,
+ struct sparc_stackf __user *src)
+{
+ unsigned long size, fp;
+ struct sparc_stackf *tmp;
+ struct sparc_stackf __user *sp;
+
+ if (get_user(tmp, &src->fp))
+ return NULL;
+
+ fp = (unsigned long) tmp;
+ size = (fp - ((unsigned long) src));
+ fp = (unsigned long) dst;
+ sp = (struct sparc_stackf __user *)(fp - size);
+
+ /* do_fork() grabs the parent semaphore, we must release it
+ * temporarily so we can build the child clone stack frame
+ * without deadlocking.
+ */
+ if (__copy_user(sp, src, size))
+ sp = NULL;
+ else if (put_user(fp, &sp->fp))
+ sp = NULL;
+
+ return sp;
+}
+
+asmlinkage int sparc_do_fork(unsigned long clone_flags,
+ unsigned long stack_start,
+ struct pt_regs *regs,
+ unsigned long stack_size)
+{
+ unsigned long parent_tid_ptr, child_tid_ptr;
+ unsigned long orig_i1 = regs->u_regs[UREG_I1];
+ long ret;
+
+ parent_tid_ptr = regs->u_regs[UREG_I2];
+ child_tid_ptr = regs->u_regs[UREG_I4];
+
+ ret = do_fork(clone_flags, stack_start, stack_size,
+ (int __user *) parent_tid_ptr,
+ (int __user *) child_tid_ptr);
+
+ /* If we get an error and potentially restart the system
+ * call, we're screwed because copy_thread() clobbered
+ * the parent's %o1. So detect that case and restore it
+ * here.
+ */
+ if ((unsigned long)ret >= -ERESTART_RESTARTBLOCK)
+ regs->u_regs[UREG_I1] = orig_i1;
+
+ return ret;
+}
+
+/* Copy a Sparc thread. The fork() return value conventions
+ * under SunOS are nothing short of bletcherous:
+ * Parent --> %o0 == childs pid, %o1 == 0
+ * Child --> %o0 == parents pid, %o1 == 1
+ *
+ * NOTE: We have a separate fork kpsr/kwim because
+ * the parent could change these values between
+ * sys_fork invocation and when we reach here
+ * if the parent should sleep while trying to
+ * allocate the task_struct and kernel stack in
+ * do_fork().
+ * XXX See comment above sys_vfork in sparc64. todo.
+ */
+extern void ret_from_fork(void);
+extern void ret_from_kernel_thread(void);
+
+int copy_thread(unsigned long clone_flags, unsigned long sp,
+ unsigned long arg, struct task_struct *p)
+{
+ struct thread_info *ti = task_thread_info(p);
+ struct pt_regs *childregs, *regs = current_pt_regs();
+ char *new_stack;
+
+#ifndef CONFIG_SMP
+ if(last_task_used_math == current) {
+#else
+ if (test_thread_flag(TIF_USEDFPU)) {
+#endif
+ put_psr(get_psr() | PSR_EF);
+ fpsave(&p->thread.float_regs[0], &p->thread.fsr,
+ &p->thread.fpqueue[0], &p->thread.fpqdepth);
+ }
+
+ /*
+ * p->thread_info new_stack childregs stack bottom
+ * ! ! ! !
+ * V V (stk.fr.) V (pt_regs) V
+ * +----- - - - - - ------+===========+=============+
+ */
+ new_stack = task_stack_page(p) + THREAD_SIZE;
+ new_stack -= STACKFRAME_SZ + TRACEREG_SZ;
+ childregs = (struct pt_regs *) (new_stack + STACKFRAME_SZ);
+
+ /*
+ * A new process must start with interrupts disabled, see schedule_tail()
+ * and finish_task_switch(). (If we do not do it and if a timer interrupt
+ * hits before we unlock and attempts to take the rq->lock, we deadlock.)
+ *
+ * Thus, kpsr |= PSR_PIL.
+ */
+ ti->ksp = (unsigned long) new_stack;
+ p->thread.kregs = childregs;
+
+ if (unlikely(p->flags & PF_KTHREAD)) {
+ extern int nwindows;
+ unsigned long psr;
+ memset(new_stack, 0, STACKFRAME_SZ + TRACEREG_SZ);
+ p->thread.flags |= SPARC_FLAG_KTHREAD;
+ p->thread.current_ds = KERNEL_DS;
+ ti->kpc = (((unsigned long) ret_from_kernel_thread) - 0x8);
+ childregs->u_regs[UREG_G1] = sp; /* function */
+ childregs->u_regs[UREG_G2] = arg;
+ psr = childregs->psr = get_psr();
+ ti->kpsr = psr | PSR_PIL;
+ ti->kwim = 1 << (((psr & PSR_CWP) + 1) % nwindows);
+ return 0;
+ }
+ memcpy(new_stack, (char *)regs - STACKFRAME_SZ, STACKFRAME_SZ + TRACEREG_SZ);
+ childregs->u_regs[UREG_FP] = sp;
+ p->thread.flags &= ~SPARC_FLAG_KTHREAD;
+ p->thread.current_ds = USER_DS;
+ ti->kpc = (((unsigned long) ret_from_fork) - 0x8);
+ ti->kpsr = current->thread.fork_kpsr | PSR_PIL;
+ ti->kwim = current->thread.fork_kwim;
+
+ if (sp != regs->u_regs[UREG_FP]) {
+ struct sparc_stackf __user *childstack;
+ struct sparc_stackf __user *parentstack;
+
+ /*
+ * This is a clone() call with supplied user stack.
+ * Set some valid stack frames to give to the child.
+ */
+ childstack = (struct sparc_stackf __user *)
+ (sp & ~0xfUL);
+ parentstack = (struct sparc_stackf __user *)
+ regs->u_regs[UREG_FP];
+
+#if 0
+ printk("clone: parent stack:\n");
+ show_stackframe(parentstack);
+#endif
+
+ childstack = clone_stackframe(childstack, parentstack);
+ if (!childstack)
+ return -EFAULT;
+
+#if 0
+ printk("clone: child stack:\n");
+ show_stackframe(childstack);
+#endif
+
+ childregs->u_regs[UREG_FP] = (unsigned long)childstack;
+ }
+
+#ifdef CONFIG_SMP
+ /* FPU must be disabled on SMP. */
+ childregs->psr &= ~PSR_EF;
+ clear_tsk_thread_flag(p, TIF_USEDFPU);
+#endif
+
+ /* Set the return value for the child. */
+ childregs->u_regs[UREG_I0] = current->pid;
+ childregs->u_regs[UREG_I1] = 1;
+
+ /* Set the return value for the parent. */
+ regs->u_regs[UREG_I1] = 0;
+
+ if (clone_flags & CLONE_SETTLS)
+ childregs->u_regs[UREG_G7] = regs->u_regs[UREG_I3];
+
+ return 0;
+}
+
+/*
+ * fill in the fpu structure for a core dump.
+ */
+int dump_fpu (struct pt_regs * regs, elf_fpregset_t * fpregs)
+{
+ if (used_math()) {
+ memset(fpregs, 0, sizeof(*fpregs));
+ fpregs->pr_q_entrysize = 8;
+ return 1;
+ }
+#ifdef CONFIG_SMP
+ if (test_thread_flag(TIF_USEDFPU)) {
+ put_psr(get_psr() | PSR_EF);
+ fpsave(¤t->thread.float_regs[0], ¤t->thread.fsr,
+ ¤t->thread.fpqueue[0], ¤t->thread.fpqdepth);
+ if (regs != NULL) {
+ regs->psr &= ~(PSR_EF);
+ clear_thread_flag(TIF_USEDFPU);
+ }
+ }
+#else
+ if (current == last_task_used_math) {
+ put_psr(get_psr() | PSR_EF);
+ fpsave(¤t->thread.float_regs[0], ¤t->thread.fsr,
+ ¤t->thread.fpqueue[0], ¤t->thread.fpqdepth);
+ if (regs != NULL) {
+ regs->psr &= ~(PSR_EF);
+ last_task_used_math = NULL;
+ }
+ }
+#endif
+ memcpy(&fpregs->pr_fr.pr_regs[0],
+ ¤t->thread.float_regs[0],
+ (sizeof(unsigned long) * 32));
+ fpregs->pr_fsr = current->thread.fsr;
+ fpregs->pr_qcnt = current->thread.fpqdepth;
+ fpregs->pr_q_entrysize = 8;
+ fpregs->pr_en = 1;
+ if(fpregs->pr_qcnt != 0) {
+ memcpy(&fpregs->pr_q[0],
+ ¤t->thread.fpqueue[0],
+ sizeof(struct fpq) * fpregs->pr_qcnt);
+ }
+ /* Zero out the rest. */
+ memset(&fpregs->pr_q[fpregs->pr_qcnt], 0,
+ sizeof(struct fpq) * (32 - fpregs->pr_qcnt));
+ return 1;
+}
+
+unsigned long get_wchan(struct task_struct *task)
+{
+ unsigned long pc, fp, bias = 0;
+ unsigned long task_base = (unsigned long) task;
+ unsigned long ret = 0;
+ struct reg_window32 *rw;
+ int count = 0;
+
+ if (!task || task == current ||
+ task->state == TASK_RUNNING)
+ goto out;
+
+ fp = task_thread_info(task)->ksp + bias;
+ do {
+ /* Bogus frame pointer? */
+ if (fp < (task_base + sizeof(struct thread_info)) ||
+ fp >= (task_base + (2 * PAGE_SIZE)))
+ break;
+ rw = (struct reg_window32 *) fp;
+ pc = rw->ins[7];
+ if (!in_sched_functions(pc)) {
+ ret = pc;
+ goto out;
+ }
+ fp = rw->ins[6] + bias;
+ } while (++count < 16);
+
+out:
+ return ret;
+}
+