summaryrefslogtreecommitdiffstats
path: root/arch/parisc/kernel/process.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /arch/parisc/kernel/process.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/parisc/kernel/process.c')
-rw-r--r--arch/parisc/kernel/process.c302
1 files changed, 302 insertions, 0 deletions
diff --git a/arch/parisc/kernel/process.c b/arch/parisc/kernel/process.c
new file mode 100644
index 000000000..b62d60009
--- /dev/null
+++ b/arch/parisc/kernel/process.c
@@ -0,0 +1,302 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * PARISC Architecture-dependent parts of process handling
+ * based on the work for i386
+ *
+ * Copyright (C) 1999-2003 Matthew Wilcox <willy at parisc-linux.org>
+ * Copyright (C) 2000 Martin K Petersen <mkp at mkp.net>
+ * Copyright (C) 2000 John Marvin <jsm at parisc-linux.org>
+ * Copyright (C) 2000 David Huggins-Daines <dhd with pobox.org>
+ * Copyright (C) 2000-2003 Paul Bame <bame at parisc-linux.org>
+ * Copyright (C) 2000 Philipp Rumpf <prumpf with tux.org>
+ * Copyright (C) 2000 David Kennedy <dkennedy with linuxcare.com>
+ * Copyright (C) 2000 Richard Hirst <rhirst with parisc-linux.org>
+ * Copyright (C) 2000 Grant Grundler <grundler with parisc-linux.org>
+ * Copyright (C) 2001 Alan Modra <amodra at parisc-linux.org>
+ * Copyright (C) 2001-2002 Ryan Bradetich <rbrad at parisc-linux.org>
+ * Copyright (C) 2001-2014 Helge Deller <deller@gmx.de>
+ * Copyright (C) 2002 Randolph Chung <tausq with parisc-linux.org>
+ */
+#include <linux/elf.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/fs.h>
+#include <linux/cpu.h>
+#include <linux/module.h>
+#include <linux/personality.h>
+#include <linux/ptrace.h>
+#include <linux/reboot.h>
+#include <linux/sched.h>
+#include <linux/sched/debug.h>
+#include <linux/sched/task.h>
+#include <linux/sched/task_stack.h>
+#include <linux/slab.h>
+#include <linux/stddef.h>
+#include <linux/unistd.h>
+#include <linux/kallsyms.h>
+#include <linux/uaccess.h>
+#include <linux/rcupdate.h>
+#include <linux/random.h>
+#include <linux/nmi.h>
+#include <linux/sched/hotplug.h>
+
+#include <asm/io.h>
+#include <asm/asm-offsets.h>
+#include <asm/assembly.h>
+#include <asm/pdc.h>
+#include <asm/pdc_chassis.h>
+#include <asm/unwind.h>
+#include <asm/sections.h>
+#include <asm/cacheflush.h>
+
+#define COMMAND_GLOBAL F_EXTEND(0xfffe0030)
+#define CMD_RESET 5 /* reset any module */
+
+/*
+** The Wright Brothers and Gecko systems have a H/W problem
+** (Lasi...'nuf said) may cause a broadcast reset to lockup
+** the system. An HVERSION dependent PDC call was developed
+** to perform a "safe", platform specific broadcast reset instead
+** of kludging up all the code.
+**
+** Older machines which do not implement PDC_BROADCAST_RESET will
+** return (with an error) and the regular broadcast reset can be
+** issued. Obviously, if the PDC does implement PDC_BROADCAST_RESET
+** the PDC call will not return (the system will be reset).
+*/
+void machine_restart(char *cmd)
+{
+#ifdef FASTBOOT_SELFTEST_SUPPORT
+ /*
+ ** If user has modified the Firmware Selftest Bitmap,
+ ** run the tests specified in the bitmap after the
+ ** system is rebooted w/PDC_DO_RESET.
+ **
+ ** ftc_bitmap = 0x1AUL "Skip destructive memory tests"
+ **
+ ** Using "directed resets" at each processor with the MEM_TOC
+ ** vector cleared will also avoid running destructive
+ ** memory self tests. (Not implemented yet)
+ */
+ if (ftc_bitmap) {
+ pdc_do_firm_test_reset(ftc_bitmap);
+ }
+#endif
+ /* set up a new led state on systems shipped with a LED State panel */
+ pdc_chassis_send_status(PDC_CHASSIS_DIRECT_SHUTDOWN);
+
+ /* "Normal" system reset */
+ pdc_do_reset();
+
+ /* Nope...box should reset with just CMD_RESET now */
+ gsc_writel(CMD_RESET, COMMAND_GLOBAL);
+
+ /* Wait for RESET to lay us to rest. */
+ while (1) ;
+
+}
+
+void (*chassis_power_off)(void);
+
+/*
+ * This routine is called from sys_reboot to actually turn off the
+ * machine
+ */
+void machine_power_off(void)
+{
+ /* If there is a registered power off handler, call it. */
+ if (chassis_power_off)
+ chassis_power_off();
+
+ /* Put the soft power button back under hardware control.
+ * If the user had already pressed the power button, the
+ * following call will immediately power off. */
+ pdc_soft_power_button(0);
+
+ pdc_chassis_send_status(PDC_CHASSIS_DIRECT_SHUTDOWN);
+
+ /* ipmi_poweroff may have been installed. */
+ do_kernel_power_off();
+
+ /* It seems we have no way to power the system off via
+ * software. The user has to press the button himself. */
+
+ printk("Power off or press RETURN to reboot.\n");
+
+ /* prevent soft lockup/stalled CPU messages for endless loop. */
+ rcu_sysrq_start();
+ lockup_detector_soft_poweroff();
+ while (1) {
+ /* reboot if user presses RETURN key */
+ if (pdc_iodc_getc() == 13) {
+ printk("Rebooting...\n");
+ machine_restart(NULL);
+ }
+ }
+}
+
+void (*pm_power_off)(void);
+EXPORT_SYMBOL(pm_power_off);
+
+void machine_halt(void)
+{
+ machine_power_off();
+}
+
+void flush_thread(void)
+{
+ /* Only needs to handle fpu stuff or perf monitors.
+ ** REVISIT: several arches implement a "lazy fpu state".
+ */
+}
+
+/*
+ * Idle thread support
+ *
+ * Detect when running on QEMU with SeaBIOS PDC Firmware and let
+ * QEMU idle the host too.
+ */
+
+int running_on_qemu __ro_after_init;
+EXPORT_SYMBOL(running_on_qemu);
+
+/*
+ * Called from the idle thread for the CPU which has been shutdown.
+ */
+void arch_cpu_idle_dead(void)
+{
+#ifdef CONFIG_HOTPLUG_CPU
+ idle_task_exit();
+
+ local_irq_disable();
+
+ /* Tell __cpu_die() that this CPU is now safe to dispose of. */
+ (void)cpu_report_death();
+
+ /* Ensure that the cache lines are written out. */
+ flush_cache_all_local();
+ flush_tlb_all_local(NULL);
+
+ /* Let PDC firmware put CPU into firmware idle loop. */
+ __pdc_cpu_rendezvous();
+
+ pr_warn("PDC does not provide rendezvous function.\n");
+#endif
+ while (1);
+}
+
+void __cpuidle arch_cpu_idle(void)
+{
+ raw_local_irq_enable();
+
+ /* nop on real hardware, qemu will idle sleep. */
+ asm volatile("or %%r10,%%r10,%%r10\n":::);
+}
+
+static int __init parisc_idle_init(void)
+{
+ if (!running_on_qemu)
+ cpu_idle_poll_ctrl(1);
+
+ return 0;
+}
+arch_initcall(parisc_idle_init);
+
+/*
+ * Copy architecture-specific thread state
+ */
+int
+copy_thread(struct task_struct *p, const struct kernel_clone_args *args)
+{
+ unsigned long clone_flags = args->flags;
+ unsigned long usp = args->stack;
+ unsigned long tls = args->tls;
+ struct pt_regs *cregs = &(p->thread.regs);
+ void *stack = task_stack_page(p);
+
+ /* We have to use void * instead of a function pointer, because
+ * function pointers aren't a pointer to the function on 64-bit.
+ * Make them const so the compiler knows they live in .text */
+ extern void * const ret_from_kernel_thread;
+ extern void * const child_return;
+
+ if (unlikely(args->fn)) {
+ /* kernel thread */
+ memset(cregs, 0, sizeof(struct pt_regs));
+ if (args->idle) /* idle thread */
+ return 0;
+ /* Must exit via ret_from_kernel_thread in order
+ * to call schedule_tail()
+ */
+ cregs->ksp = (unsigned long) stack + FRAME_SIZE + PT_SZ_ALGN;
+ cregs->kpc = (unsigned long) &ret_from_kernel_thread;
+ /*
+ * Copy function and argument to be called from
+ * ret_from_kernel_thread.
+ */
+#ifdef CONFIG_64BIT
+ cregs->gr[27] = ((unsigned long *)args->fn)[3];
+ cregs->gr[26] = ((unsigned long *)args->fn)[2];
+#else
+ cregs->gr[26] = (unsigned long) args->fn;
+#endif
+ cregs->gr[25] = (unsigned long) args->fn_arg;
+ } else {
+ /* user thread */
+ /* usp must be word aligned. This also prevents users from
+ * passing in the value 1 (which is the signal for a special
+ * return for a kernel thread) */
+ if (usp) {
+ usp = ALIGN(usp, 4);
+ if (likely(usp))
+ cregs->gr[30] = usp;
+ }
+ cregs->ksp = (unsigned long) stack + FRAME_SIZE;
+ cregs->kpc = (unsigned long) &child_return;
+
+ /* Setup thread TLS area */
+ if (clone_flags & CLONE_SETTLS)
+ cregs->cr27 = tls;
+ }
+
+ return 0;
+}
+
+unsigned long
+__get_wchan(struct task_struct *p)
+{
+ struct unwind_frame_info info;
+ unsigned long ip;
+ int count = 0;
+
+ /*
+ * These bracket the sleeping functions..
+ */
+
+ unwind_frame_init_from_blocked_task(&info, p);
+ do {
+ if (unwind_once(&info) < 0)
+ return 0;
+ if (task_is_running(p))
+ return 0;
+ ip = info.ip;
+ if (!in_sched_functions(ip))
+ return ip;
+ } while (count++ < MAX_UNWIND_ENTRIES);
+ return 0;
+}
+
+static inline unsigned long brk_rnd(void)
+{
+ return (get_random_u32() & BRK_RND_MASK) << PAGE_SHIFT;
+}
+
+unsigned long arch_randomize_brk(struct mm_struct *mm)
+{
+ unsigned long ret = PAGE_ALIGN(mm->brk + brk_rnd());
+
+ if (ret < mm->brk)
+ return mm->brk;
+ return ret;
+}