diff options
Diffstat (limited to 'arch/x86/kernel/apm_32.c')
| -rw-r--r-- | arch/x86/kernel/apm_32.c | 92 |
1 files changed, 25 insertions, 67 deletions
diff --git a/arch/x86/kernel/apm_32.c b/arch/x86/kernel/apm_32.c index 446b0d3d4932..b37ab1095707 100644 --- a/arch/x86/kernel/apm_32.c +++ b/arch/x86/kernel/apm_32.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0-or-later /* -*- linux-c -*- * APM BIOS driver for Linux * Copyright 1994-2001 Stephen Rothwell (sfr@canb.auug.org.au) @@ -5,16 +6,6 @@ * Initial development of this driver was funded by NEC Australia P/L * and NEC Corporation * - * This program is free software; you can redistribute it and/or modify it - * under the terms of the GNU General Public License as published by the - * Free Software Foundation; either version 2, or (at your option) any - * later version. - * - * This program is distributed in the hope that it will be useful, but - * WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - * General Public License for more details. - * * October 1995, Rik Faith (faith@cs.unc.edu): * Minor enhancements and updates (to the patch set) for 1.3.x * Documentation @@ -103,7 +94,7 @@ * Remove APM dependencies in arch/i386/kernel/process.c * Remove APM dependencies in drivers/char/sysrq.c * Reset time across standby. - * Allow more inititialisation on SMP. + * Allow more initialisation on SMP. * Remove CONFIG_APM_POWER_OFF and make it boot time * configurable (default on). * Make debug only a boot time parameter (remove APM_DEBUG). @@ -240,18 +231,14 @@ #include <asm/olpc.h> #include <asm/paravirt.h> #include <asm/reboot.h> +#include <asm/nospec-branch.h> +#include <asm/ibt.h> #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT) extern int (*console_blank_hook)(int); #endif /* - * The apm_bios device is one of the misc char devices. - * This is its minor number. - */ -#define APM_MINOR_DEV 134 - -/* * Various options can be changed at boot time as follows: * (We allow underscores for compatibility with the modules code) * apm=on/off enable/disable APM @@ -433,7 +420,7 @@ static DEFINE_MUTEX(apm_mutex); * This is for buggy BIOS's that refer to (real mode) segment 0x40 * even though they are called in protected mode. */ -static struct desc_struct bad_bios_desc = GDT_ENTRY_INIT(0x4092, +static struct desc_struct bad_bios_desc = GDT_ENTRY_INIT(DESC_DATA32_BIOS, (unsigned long)__va(0x400UL), PAGE_SIZE - 0x400 - 1); static const char driver_version[] = "1.16ac"; /* no spaces */ @@ -606,6 +593,7 @@ static long __apm_bios_call(void *_call) struct desc_struct save_desc_40; struct desc_struct *gdt; struct apm_bios_call *call = _call; + u64 ibt; cpu = get_cpu(); BUG_ON(cpu != 0); @@ -614,11 +602,15 @@ static long __apm_bios_call(void *_call) gdt[0x40 / 8] = bad_bios_desc; apm_irq_save(flags); + firmware_restrict_branch_speculation_start(); + ibt = ibt_save(true); APM_DO_SAVE_SEGS; apm_bios_call_asm(call->func, call->ebx, call->ecx, &call->eax, &call->ebx, &call->ecx, &call->edx, &call->esi); APM_DO_RESTORE_SEGS; + ibt_restore(ibt); + firmware_restrict_branch_speculation_end(); apm_irq_restore(flags); gdt[0x40 / 8] = save_desc_40; put_cpu(); @@ -682,6 +674,7 @@ static long __apm_bios_call_simple(void *_call) struct desc_struct save_desc_40; struct desc_struct *gdt; struct apm_bios_call *call = _call; + u64 ibt; cpu = get_cpu(); BUG_ON(cpu != 0); @@ -690,10 +683,14 @@ static long __apm_bios_call_simple(void *_call) gdt[0x40 / 8] = bad_bios_desc; apm_irq_save(flags); + firmware_restrict_branch_speculation_start(); + ibt = ibt_save(true); APM_DO_SAVE_SEGS; error = apm_bios_call_simple_asm(call->func, call->ebx, call->ecx, &call->eax); APM_DO_RESTORE_SEGS; + ibt_restore(ibt); + firmware_restrict_branch_speculation_end(); apm_irq_restore(flags); gdt[0x40 / 8] = save_desc_40; put_cpu(); @@ -770,7 +767,7 @@ static int apm_driver_version(u_short *val) * not cleared until it is acknowledged. * * Additional information is returned in the info pointer, providing - * that APM 1.2 is in use. If no messges are pending the value 0x80 + * that APM 1.2 is in use. If no messages are pending the value 0x80 * is returned (No power management events pending). */ static int apm_get_event(apm_event_t *event, apm_eventinfo_t *info) @@ -1029,7 +1026,7 @@ static int apm_enable_power_management(int enable) * status which gives the rough battery status, and current power * source. The bat value returned give an estimate as a percentage * of life and a status value for the battery. The estimated life - * if reported is a lifetime in secodnds/minutes at current powwer + * if reported is a lifetime in seconds/minutes at current power * consumption. */ @@ -1058,35 +1055,6 @@ static int apm_get_power_status(u_short *status, u_short *bat, u_short *life) return APM_SUCCESS; } -#if 0 -static int apm_get_battery_status(u_short which, u_short *status, - u_short *bat, u_short *life, u_short *nbat) -{ - u32 eax; - u32 ebx; - u32 ecx; - u32 edx; - u32 esi; - - if (apm_info.connection_version < 0x0102) { - /* pretend we only have one battery. */ - if (which != 1) - return APM_BAD_DEVICE; - *nbat = 1; - return apm_get_power_status(status, bat, life); - } - - if (apm_bios_call(APM_FUNC_GET_STATUS, (0x8000 | (which)), 0, &eax, - &ebx, &ecx, &edx, &esi)) - return (eax >> 8) & 0xff; - *status = ebx; - *bat = ecx; - *life = edx; - *nbat = esi; - return APM_SUCCESS; -} -#endif - /** * apm_engage_power_management - enable PM on a device * @device: identity of device @@ -1506,7 +1474,7 @@ static ssize_t do_read(struct file *fp, char __user *buf, size_t count, loff_t * return 0; } -static unsigned int do_poll(struct file *fp, poll_table *wait) +static __poll_t do_poll(struct file *fp, poll_table *wait) { struct apm_user *as; @@ -1515,7 +1483,7 @@ static unsigned int do_poll(struct file *fp, poll_table *wait) return 0; poll_wait(fp, &apm_waitqueue, wait); if (!queue_empty(as)) - return POLLIN | POLLRDNORM; + return EPOLLIN | EPOLLRDNORM; return 0; } @@ -1635,6 +1603,7 @@ static int do_open(struct inode *inode, struct file *filp) return 0; } +#ifdef CONFIG_PROC_FS static int proc_apm_show(struct seq_file *m, void *v) { unsigned short bx; @@ -1714,19 +1683,7 @@ static int proc_apm_show(struct seq_file *m, void *v) units); return 0; } - -static int proc_apm_open(struct inode *inode, struct file *file) -{ - return single_open(file, proc_apm_show, NULL); -} - -static const struct file_operations apm_file_ops = { - .owner = THIS_MODULE, - .open = proc_apm_open, - .read = seq_read, - .llseek = seq_lseek, - .release = single_release, -}; +#endif static int apm(void *unused) { @@ -2043,7 +2000,7 @@ static int __init swab_apm_power_in_minutes(const struct dmi_system_id *d) return 0; } -static struct dmi_system_id __initdata apm_dmi_table[] = { +static const struct dmi_system_id apm_dmi_table[] __initconst = { { print_if_true, KERN_WARNING "IBM T23 - BIOS 1.03b+ and controller firmware 1.02+ may be needed for Linux APM.", @@ -2360,7 +2317,7 @@ static int __init apm_init(void) set_desc_base(&gdt[APM_DS >> 3], (unsigned long)__va((unsigned long)apm_info.bios.dseg << 4)); - proc_create("apm", 0, NULL, &apm_file_ops); + proc_create_single("apm", 0, NULL, proc_apm_show); kapmd_task = kthread_create(apm, NULL, "kapmd"); if (IS_ERR(kapmd_task)) { @@ -2389,6 +2346,7 @@ static int __init apm_init(void) if (HZ != 100) idle_period = (idle_period * HZ) / 100; if (idle_threshold < 100) { + cpuidle_poll_state_init(&apm_idle_driver); if (!cpuidle_register_driver(&apm_idle_driver)) if (cpuidle_register_device(&apm_cpuidle_device)) cpuidle_unregister_driver(&apm_idle_driver); @@ -2445,7 +2403,7 @@ MODULE_PARM_DESC(idle_threshold, "System idle percentage above which to make APM BIOS idle calls"); module_param(idle_period, int, 0444); MODULE_PARM_DESC(idle_period, - "Period (in sec/100) over which to caculate the idle percentage"); + "Period (in sec/100) over which to calculate the idle percentage"); module_param(smp, bool, 0444); MODULE_PARM_DESC(smp, "Set this to enable APM use on an SMP platform. Use with caution on older systems"); |