// SPDX-License-Identifier: GPL-2.0
/*
* PPC Huge TLB Page Support for Book3E MMU
*
* Copyright (C) 2009 David Gibson, IBM Corporation.
* Copyright (C) 2011 Becky Bruce, Freescale Semiconductor
*
*/
#include <linux/mm.h>
#include <linux/hugetlb.h>
#include <asm/mmu.h>
#ifdef CONFIG_PPC64
#include <asm/paca.h>
static inline int tlb1_next(void)
{
struct paca_struct *paca = get_paca();
struct tlb_core_data *tcd;
int this, next;
tcd = paca->tcd_ptr;
this = tcd->esel_next;
next = this + 1;
if (next >= tcd->esel_max)
next = tcd->esel_first;
tcd->esel_next = next;
return this;
}
static inline void book3e_tlb_lock(void)
{
struct paca_struct *paca = get_paca();
unsigned long tmp;
int token = smp_processor_id() + 1;
/*
* Besides being unnecessary in the absence of SMT, this
* check prevents trying to do lbarx/stbcx. on e5500 which
* doesn't implement either feature.
*/
if (!cpu_has_feature(CPU_FTR_SMT))
return;
asm volatile(".machine push;"
".machine e6500;"
"1: lbarx %0, 0, %1;"
"cmpwi %0, 0;"
"bne 2f;"
"stbcx. %2, 0, %1;"
"bne 1b;"
"b 3f;"
"2: lbzx %0, 0, %1;"
"cmpwi %0, 0;"
"bne 2b;"
"b 1b;"
"3:"
".machine pop;"
: "=&r" (tmp)
: "r" (&paca->tcd_ptr->lock), "r" (token)
: "memory");
}
static inline void book3e_tlb_unlock(void)
{
struct paca_struct *paca = get_paca();
if (!cpu_has_feature(CPU_FTR_SMT))
return;
isync();
paca->tcd_ptr->lock = 0;
}
#else
static inline int tlb1_next(void)
{
int index, ncams;
ncams = mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY;
index = this_cpu_read(next_tlbcam_idx);
/* Just round-robin the entries and wrap when we hit the end */
if (unlikely(index == ncams - 1))
__this_cpu_write(next_tlbcam_idx, tlbcam_index);
else
__this_cpu_inc(next_tlbcam_idx);
return index;
}
static inline void book3e_tlb_lock(void)
{
}
static inline void book3e_tlb_unlock(void)
{
}
#endif
static inline int book3e_tlb_exists(unsigned long ea, unsigned long pid)
{
int found = 0;
mtspr(SPRN_MAS6, pid << 16);
asm volatile(
"tlbsx 0,%1\n"
"mfspr %0,0x271\n"
"srwi %0,%0,31\n"
: "=&r"(found) : "r"(ea));
return found;
}
static void
book3e_hugetlb_preload(struct vm_area_struct *vma, unsigned long ea, pte_t pte)
{
unsigned long mas1, mas2;
u64 mas7_3;
unsigned long psize, tsize, shift;
unsigned long flags;
struct mm_struct *mm;
int index;
if (unlikely(is_kernel_addr(ea)))
return;
mm = vma->vm_mm;
psize = vma_mmu_pagesize(vma);
shift = __ilog2(psize);
tsize = shift - 10;
/*
* We can't be interrupted while we're setting up the MAS
* registers or after we've confirmed that no tlb exists.
*/
local_irq_save(flags);
book3e_tlb_lock();
if (unlikely(book3e_tlb_exists(ea, mm->context.id))) {
book3e_tlb_unlock();
local_irq_restore(flags);
return;
}
/* We have to use the CAM(TLB1) on FSL parts for hugepages */
index = tlb1_next();
mtspr(SPRN_MAS0, MAS0_ESEL(index) | MAS0_TLBSEL(1));
mas1 = MAS1_VALID | MAS1_TID(mm->context.id) | MAS1_TSIZE(tsize);
mas2 = ea & ~((1UL << shift) - 1);
mas2 |= (pte_val(pte) >> PTE_WIMGE_SHIFT) & MAS2_WIMGE_MASK;
mas7_3 = (u64)pte_pfn(pte) << PAGE_SHIFT;
mas7_3 |= (pte_val(pte) >> PTE_BAP_SHIFT) & MAS3_BAP_MASK;
if (!pte_dirty(pte))
mas7_3 &= ~(MAS3_SW|MAS3_UW);
mtspr(SPRN_MAS1, mas1);
mtspr(SPRN_MAS2, mas2);
if (mmu_has_feature(MMU_FTR_BIG_PHYS))
mtspr(SPRN_MAS7, upper_32_bits(mas7_3));
mtspr(SPRN_MAS3, lower_32_bits(mas7_3));
asm volatile ("tlbwe");
book3e_tlb_unlock();
local_irq_restore(flags);
}
/*
* This is called at the end of handling a user page fault, when the
* fault has been handled by updating a PTE in the linux page tables.
*
* This must always be called with the pte lock held.
*/
void __update_mmu_cache(struct vm_area_struct *vma, unsigned long address, pte_t *ptep)
{
if (is_vm_hugetlb_page(vma))
book3e_hugetlb_preload(vma, address, *ptep);
}
void flush_hugetlb_page(struct vm_area_struct *vma, unsigned long vmaddr)
{
struct hstate *hstate = hstate_file(vma->vm_file);
unsigned long tsize = huge_page_shift(hstate) - 10;
__flush_tlb_page(vma->vm_mm, vmaddr, tsize, 0);
}
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