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Merge branch 'x86-platform-for-linus' of git://git.kernel.org/pub/scm…
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…/linux/kernel/git/tip/tip

Pull x86 platform updates from Ingo Molnar:
 "Two changes:

   - one to quirk-save/restore certain system MSRs across
     suspend/resume, to make certain Intel systems work better
     (Chen Yu)

   - and also to constify a read only structure (Julia Lawall)"

* 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/platform/calgary: Constify cal_chipset_ops structures
  x86/pm: Introduce quirk framework to save/restore extra MSR registers around suspend/resume
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torvalds committed Jan 12, 2016
2 parents 0ffedcd + d6b56b0 commit ae8a521
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Showing 6 changed files with 107 additions and 3 deletions.
2 changes: 1 addition & 1 deletion arch/x86/include/asm/calgary.h
Original file line number Diff line number Diff line change
Expand Up @@ -31,7 +31,7 @@
#include <asm/types.h>

struct iommu_table {
struct cal_chipset_ops *chip_ops; /* chipset specific funcs */
const struct cal_chipset_ops *chip_ops; /* chipset specific funcs */
unsigned long it_base; /* mapped address of tce table */
unsigned long it_hint; /* Hint for next alloc */
unsigned long *it_map; /* A simple allocation bitmap for now */
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10 changes: 10 additions & 0 deletions arch/x86/include/asm/msr.h
Original file line number Diff line number Diff line change
Expand Up @@ -32,6 +32,16 @@ struct msr_regs_info {
int err;
};

struct saved_msr {
bool valid;
struct msr_info info;
};

struct saved_msrs {
unsigned int num;
struct saved_msr *array;
};

static inline unsigned long long native_read_tscp(unsigned int *aux)
{
unsigned long low, high;
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1 change: 1 addition & 0 deletions arch/x86/include/asm/suspend_32.h
Original file line number Diff line number Diff line change
Expand Up @@ -15,6 +15,7 @@ struct saved_context {
unsigned long cr0, cr2, cr3, cr4;
u64 misc_enable;
bool misc_enable_saved;
struct saved_msrs saved_msrs;
struct desc_ptr gdt_desc;
struct desc_ptr idt;
u16 ldt;
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1 change: 1 addition & 0 deletions arch/x86/include/asm/suspend_64.h
Original file line number Diff line number Diff line change
Expand Up @@ -24,6 +24,7 @@ struct saved_context {
unsigned long cr0, cr2, cr3, cr4, cr8;
u64 misc_enable;
bool misc_enable_saved;
struct saved_msrs saved_msrs;
unsigned long efer;
u16 gdt_pad; /* Unused */
struct desc_ptr gdt_desc;
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4 changes: 2 additions & 2 deletions arch/x86/kernel/pci-calgary_64.c
Original file line number Diff line number Diff line change
Expand Up @@ -180,13 +180,13 @@ static void calioc2_dump_error_regs(struct iommu_table *tbl);
static void calgary_init_bitmap_from_tce_table(struct iommu_table *tbl);
static void get_tce_space_from_tar(void);

static struct cal_chipset_ops calgary_chip_ops = {
static const struct cal_chipset_ops calgary_chip_ops = {
.handle_quirks = calgary_handle_quirks,
.tce_cache_blast = calgary_tce_cache_blast,
.dump_error_regs = calgary_dump_error_regs
};

static struct cal_chipset_ops calioc2_chip_ops = {
static const struct cal_chipset_ops calioc2_chip_ops = {
.handle_quirks = calioc2_handle_quirks,
.tce_cache_blast = calioc2_tce_cache_blast,
.dump_error_regs = calioc2_dump_error_regs
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92 changes: 92 additions & 0 deletions arch/x86/power/cpu.c
Original file line number Diff line number Diff line change
Expand Up @@ -23,6 +23,7 @@
#include <asm/debugreg.h>
#include <asm/cpu.h>
#include <asm/mmu_context.h>
#include <linux/dmi.h>

#ifdef CONFIG_X86_32
__visible unsigned long saved_context_ebx;
Expand All @@ -32,6 +33,29 @@ __visible unsigned long saved_context_eflags;
#endif
struct saved_context saved_context;

static void msr_save_context(struct saved_context *ctxt)
{
struct saved_msr *msr = ctxt->saved_msrs.array;
struct saved_msr *end = msr + ctxt->saved_msrs.num;

while (msr < end) {
msr->valid = !rdmsrl_safe(msr->info.msr_no, &msr->info.reg.q);
msr++;
}
}

static void msr_restore_context(struct saved_context *ctxt)
{
struct saved_msr *msr = ctxt->saved_msrs.array;
struct saved_msr *end = msr + ctxt->saved_msrs.num;

while (msr < end) {
if (msr->valid)
wrmsrl(msr->info.msr_no, msr->info.reg.q);
msr++;
}
}

/**
* __save_processor_state - save CPU registers before creating a
* hibernation image and before restoring the memory state from it
Expand Down Expand Up @@ -111,6 +135,7 @@ static void __save_processor_state(struct saved_context *ctxt)
#endif
ctxt->misc_enable_saved = !rdmsrl_safe(MSR_IA32_MISC_ENABLE,
&ctxt->misc_enable);
msr_save_context(ctxt);
}

/* Needed by apm.c */
Expand Down Expand Up @@ -229,6 +254,7 @@ static void notrace __restore_processor_state(struct saved_context *ctxt)
x86_platform.restore_sched_clock_state();
mtrr_bp_restore();
perf_restore_debug_store();
msr_restore_context(ctxt);
}

/* Needed by apm.c */
Expand Down Expand Up @@ -320,3 +346,69 @@ static int __init bsp_pm_check_init(void)
}

core_initcall(bsp_pm_check_init);

static int msr_init_context(const u32 *msr_id, const int total_num)
{
int i = 0;
struct saved_msr *msr_array;

if (saved_context.saved_msrs.array || saved_context.saved_msrs.num > 0) {
pr_err("x86/pm: MSR quirk already applied, please check your DMI match table.\n");
return -EINVAL;
}

msr_array = kmalloc_array(total_num, sizeof(struct saved_msr), GFP_KERNEL);
if (!msr_array) {
pr_err("x86/pm: Can not allocate memory to save/restore MSRs during suspend.\n");
return -ENOMEM;
}

for (i = 0; i < total_num; i++) {
msr_array[i].info.msr_no = msr_id[i];
msr_array[i].valid = false;
msr_array[i].info.reg.q = 0;
}
saved_context.saved_msrs.num = total_num;
saved_context.saved_msrs.array = msr_array;

return 0;
}

/*
* The following section is a quirk framework for problematic BIOSen:
* Sometimes MSRs are modified by the BIOSen after suspended to
* RAM, this might cause unexpected behavior after wakeup.
* Thus we save/restore these specified MSRs across suspend/resume
* in order to work around it.
*
* For any further problematic BIOSen/platforms,
* please add your own function similar to msr_initialize_bdw.
*/
static int msr_initialize_bdw(const struct dmi_system_id *d)
{
/* Add any extra MSR ids into this array. */
u32 bdw_msr_id[] = { MSR_IA32_THERM_CONTROL };

pr_info("x86/pm: %s detected, MSR saving is needed during suspending.\n", d->ident);
return msr_init_context(bdw_msr_id, ARRAY_SIZE(bdw_msr_id));
}

static struct dmi_system_id msr_save_dmi_table[] = {
{
.callback = msr_initialize_bdw,
.ident = "BROADWELL BDX_EP",
.matches = {
DMI_MATCH(DMI_PRODUCT_NAME, "GRANTLEY"),
DMI_MATCH(DMI_PRODUCT_VERSION, "E63448-400"),
},
},
{}
};

static int pm_check_save_msr(void)
{
dmi_check_system(msr_save_dmi_table);
return 0;
}

device_initcall(pm_check_save_msr);

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