linux/arch/x86/kernel/x86_init.c

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x86: Add x86_init infrastructure The upcoming Moorestown support brings the embedded world to x86. The setup code of x86 has already a couple of hooks which are either x86_quirks or paravirt ops. Some of those setup hooks are pretty convoluted like the timer setup and the tsc calibration code. But there are other places which could do with a cleanup. Instead of having inline functions/macros which are modified at compile time I decided to introduce x86_init ops which are unconditional in the code and make it clear that they can be changed either during compile time or in the early boot process. The function pointers are initialized by default functions which can be noops so that the pointer can be called unconditionally in the most cases. This also allows us to remove 32bit/64bit, paravirt and other #ifdeffery. paravirt guests are just a hardware platform in the setup code, so we should treat them as such and not hide all behind multiple layers of indirection and compile time dependencies. It's more obvious that x86_init.timers.timer_init() is a function pointer than the late_time_init = choose_time_init() obscurity. It's also way simpler to grep for x86_init.timers.timer_init and find all the places which modify that function pointer instead of analyzing weak functions, macros and paravirt indirections. Note. This is not a general paravirt_ops replacement. It just will move setup related hooks which are potentially useful for other platform setup purposes as well out of the paravirt domain. Add the base infrastructure without any functionality. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-19 12:48:38 +00:00
/*
* Copyright (C) 2009 Thomas Gleixner <tglx@linutronix.de>
*
* For licencing details see kernel-base/COPYING
*/
#include <linux/init.h>
#include <linux/ioport.h>
#include <linux/module.h>
#include <linux/pci.h>
x86: Add x86_init infrastructure The upcoming Moorestown support brings the embedded world to x86. The setup code of x86 has already a couple of hooks which are either x86_quirks or paravirt ops. Some of those setup hooks are pretty convoluted like the timer setup and the tsc calibration code. But there are other places which could do with a cleanup. Instead of having inline functions/macros which are modified at compile time I decided to introduce x86_init ops which are unconditional in the code and make it clear that they can be changed either during compile time or in the early boot process. The function pointers are initialized by default functions which can be noops so that the pointer can be called unconditionally in the most cases. This also allows us to remove 32bit/64bit, paravirt and other #ifdeffery. paravirt guests are just a hardware platform in the setup code, so we should treat them as such and not hide all behind multiple layers of indirection and compile time dependencies. It's more obvious that x86_init.timers.timer_init() is a function pointer than the late_time_init = choose_time_init() obscurity. It's also way simpler to grep for x86_init.timers.timer_init and find all the places which modify that function pointer instead of analyzing weak functions, macros and paravirt indirections. Note. This is not a general paravirt_ops replacement. It just will move setup related hooks which are potentially useful for other platform setup purposes as well out of the paravirt domain. Add the base infrastructure without any functionality. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-19 12:48:38 +00:00
#include <asm/bios_ebda.h>
#include <asm/paravirt.h>
#include <asm/pci_x86.h>
#include <asm/pci.h>
#include <asm/mpspec.h>
#include <asm/setup.h>
#include <asm/apic.h>
#include <asm/e820.h>
#include <asm/time.h>
#include <asm/irq.h>
#include <asm/pat.h>
#include <asm/tsc.h>
#include <asm/iommu.h>
x86: Add x86_init infrastructure The upcoming Moorestown support brings the embedded world to x86. The setup code of x86 has already a couple of hooks which are either x86_quirks or paravirt ops. Some of those setup hooks are pretty convoluted like the timer setup and the tsc calibration code. But there are other places which could do with a cleanup. Instead of having inline functions/macros which are modified at compile time I decided to introduce x86_init ops which are unconditional in the code and make it clear that they can be changed either during compile time or in the early boot process. The function pointers are initialized by default functions which can be noops so that the pointer can be called unconditionally in the most cases. This also allows us to remove 32bit/64bit, paravirt and other #ifdeffery. paravirt guests are just a hardware platform in the setup code, so we should treat them as such and not hide all behind multiple layers of indirection and compile time dependencies. It's more obvious that x86_init.timers.timer_init() is a function pointer than the late_time_init = choose_time_init() obscurity. It's also way simpler to grep for x86_init.timers.timer_init and find all the places which modify that function pointer instead of analyzing weak functions, macros and paravirt indirections. Note. This is not a general paravirt_ops replacement. It just will move setup related hooks which are potentially useful for other platform setup purposes as well out of the paravirt domain. Add the base infrastructure without any functionality. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-19 12:48:38 +00:00
void __cpuinit x86_init_noop(void) { }
void __init x86_init_uint_noop(unsigned int unused) { }
void __init x86_init_pgd_noop(pgd_t *unused) { }
int __init iommu_init_noop(void) { return 0; }
void iommu_shutdown_noop(void) { }
void wallclock_init_noop(void) { }
x86: Add x86_init infrastructure The upcoming Moorestown support brings the embedded world to x86. The setup code of x86 has already a couple of hooks which are either x86_quirks or paravirt ops. Some of those setup hooks are pretty convoluted like the timer setup and the tsc calibration code. But there are other places which could do with a cleanup. Instead of having inline functions/macros which are modified at compile time I decided to introduce x86_init ops which are unconditional in the code and make it clear that they can be changed either during compile time or in the early boot process. The function pointers are initialized by default functions which can be noops so that the pointer can be called unconditionally in the most cases. This also allows us to remove 32bit/64bit, paravirt and other #ifdeffery. paravirt guests are just a hardware platform in the setup code, so we should treat them as such and not hide all behind multiple layers of indirection and compile time dependencies. It's more obvious that x86_init.timers.timer_init() is a function pointer than the late_time_init = choose_time_init() obscurity. It's also way simpler to grep for x86_init.timers.timer_init and find all the places which modify that function pointer instead of analyzing weak functions, macros and paravirt indirections. Note. This is not a general paravirt_ops replacement. It just will move setup related hooks which are potentially useful for other platform setup purposes as well out of the paravirt domain. Add the base infrastructure without any functionality. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-19 12:48:38 +00:00
/*
* The platform setup functions are preset with the default functions
* for standard PC hardware.
*/
struct x86_init_ops x86_init __initdata = {
.resources = {
.probe_roms = probe_roms,
.reserve_resources = reserve_standard_io_resources,
.memory_setup = default_machine_specific_memory_setup,
},
.mpparse = {
.mpc_record = x86_init_uint_noop,
.setup_ioapic_ids = x86_init_noop,
.mpc_apic_id = default_mpc_apic_id,
.smp_read_mpc_oem = default_smp_read_mpc_oem,
.mpc_oem_bus_info = default_mpc_oem_bus_info,
.find_smp_config = default_find_smp_config,
.get_smp_config = default_get_smp_config,
},
.irqs = {
.pre_vector_init = init_ISA_irqs,
.intr_init = native_init_IRQ,
.trap_init = x86_init_noop,
},
.oem = {
.arch_setup = x86_init_noop,
.banner = default_banner,
},
x86,xen: introduce x86_init.mapping.pagetable_reserve Introduce a new x86_init hook called pagetable_reserve that at the end of init_memory_mapping is used to reserve a range of memory addresses for the kernel pagetable pages we used and free the other ones. On native it just calls memblock_x86_reserve_range while on xen it also takes care of setting the spare memory previously allocated for kernel pagetable pages from RO to RW, so that it can be used for other purposes. A detailed explanation of the reason why this hook is needed follows. As a consequence of the commit: commit 4b239f458c229de044d6905c2b0f9fe16ed9e01e Author: Yinghai Lu <yinghai@kernel.org> Date: Fri Dec 17 16:58:28 2010 -0800 x86-64, mm: Put early page table high at some point init_memory_mapping is going to reach the pagetable pages area and map those pages too (mapping them as normal memory that falls in the range of addresses passed to init_memory_mapping as argument). Some of those pages are already pagetable pages (they are in the range pgt_buf_start-pgt_buf_end) therefore they are going to be mapped RO and everything is fine. Some of these pages are not pagetable pages yet (they fall in the range pgt_buf_end-pgt_buf_top; for example the page at pgt_buf_end) so they are going to be mapped RW. When these pages become pagetable pages and are hooked into the pagetable, xen will find that the guest has already a RW mapping of them somewhere and fail the operation. The reason Xen requires pagetables to be RO is that the hypervisor needs to verify that the pagetables are valid before using them. The validation operations are called "pinning" (more details in arch/x86/xen/mmu.c). In order to fix the issue we mark all the pages in the entire range pgt_buf_start-pgt_buf_top as RO, however when the pagetable allocation is completed only the range pgt_buf_start-pgt_buf_end is reserved by init_memory_mapping. Hence the kernel is going to crash as soon as one of the pages in the range pgt_buf_end-pgt_buf_top is reused (b/c those ranges are RO). For this reason we need a hook to reserve the kernel pagetable pages we used and free the other ones so that they can be reused for other purposes. On native it just means calling memblock_x86_reserve_range, on Xen it also means marking RW the pagetable pages that we allocated before but that haven't been used before. Another way to fix this is without using the hook is by adding a 'if (xen_pv_domain)' in the 'init_memory_mapping' code and calling the Xen counterpart, but that is just nasty. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Acked-by: Yinghai Lu <yinghai@kernel.org> Acked-by: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-04-14 14:49:41 +00:00
.mapping = {
.pagetable_reserve = native_pagetable_reserve,
},
.paging = {
.pagetable_setup_start = native_pagetable_setup_start,
.pagetable_setup_done = native_pagetable_setup_done,
},
.timers = {
.setup_percpu_clockev = setup_boot_APIC_clock,
.tsc_pre_init = x86_init_noop,
.timer_init = hpet_time_init,
.wallclock_init = x86_init_noop,
},
.iommu = {
.iommu_init = iommu_init_noop,
},
.pci = {
.init = x86_default_pci_init,
.init_irq = x86_default_pci_init_irq,
.fixup_irqs = x86_default_pci_fixup_irqs,
},
};
struct x86_cpuinit_ops x86_cpuinit __cpuinitdata = {
.setup_percpu_clockev = setup_secondary_APIC_clock,
x86: Add x86_init infrastructure The upcoming Moorestown support brings the embedded world to x86. The setup code of x86 has already a couple of hooks which are either x86_quirks or paravirt ops. Some of those setup hooks are pretty convoluted like the timer setup and the tsc calibration code. But there are other places which could do with a cleanup. Instead of having inline functions/macros which are modified at compile time I decided to introduce x86_init ops which are unconditional in the code and make it clear that they can be changed either during compile time or in the early boot process. The function pointers are initialized by default functions which can be noops so that the pointer can be called unconditionally in the most cases. This also allows us to remove 32bit/64bit, paravirt and other #ifdeffery. paravirt guests are just a hardware platform in the setup code, so we should treat them as such and not hide all behind multiple layers of indirection and compile time dependencies. It's more obvious that x86_init.timers.timer_init() is a function pointer than the late_time_init = choose_time_init() obscurity. It's also way simpler to grep for x86_init.timers.timer_init and find all the places which modify that function pointer instead of analyzing weak functions, macros and paravirt indirections. Note. This is not a general paravirt_ops replacement. It just will move setup related hooks which are potentially useful for other platform setup purposes as well out of the paravirt domain. Add the base infrastructure without any functionality. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-19 12:48:38 +00:00
};
static void default_nmi_init(void) { };
static int default_i8042_detect(void) { return 1; };
struct x86_platform_ops x86_platform = {
.calibrate_tsc = native_calibrate_tsc,
.wallclock_init = wallclock_init_noop,
.get_wallclock = mach_get_cmos_time,
.set_wallclock = mach_set_rtc_mmss,
.iommu_shutdown = iommu_shutdown_noop,
.is_untracked_pat_range = is_ISA_range,
.nmi_init = default_nmi_init,
.i8042_detect = default_i8042_detect
};
EXPORT_SYMBOL_GPL(x86_platform);
struct x86_msi_ops x86_msi = {
.setup_msi_irqs = native_setup_msi_irqs,
.teardown_msi_irq = native_teardown_msi_irq,
.teardown_msi_irqs = default_teardown_msi_irqs,
};