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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_POWERPC_NOHASH_32_PGTABLE_H
#define _ASM_POWERPC_NOHASH_32_PGTABLE_H
#include <asm-generic/pgtable-nopmd.h>
#ifndef __ASSEMBLY__
#include <linux/sched.h>
#include <linux/threads.h>
#include <asm/mmu.h> /* For sub-arch specific PPC_PIN_SIZE */
#endif /* __ASSEMBLY__ */
#define PTE_INDEX_SIZE PTE_SHIFT
#define PMD_INDEX_SIZE 0
#define PUD_INDEX_SIZE 0
#define PGD_INDEX_SIZE (32 - PGDIR_SHIFT)
#define PMD_CACHE_INDEX PMD_INDEX_SIZE
#define PUD_CACHE_INDEX PUD_INDEX_SIZE
#ifndef __ASSEMBLY__
#define PTE_TABLE_SIZE (sizeof(pte_t) << PTE_INDEX_SIZE)
#define PMD_TABLE_SIZE 0
#define PUD_TABLE_SIZE 0
#define PGD_TABLE_SIZE (sizeof(pgd_t) << PGD_INDEX_SIZE)
#define PMD_MASKED_BITS (PTE_TABLE_SIZE - 1)
#endif /* __ASSEMBLY__ */
#define PTRS_PER_PTE (1 << PTE_INDEX_SIZE)
#define PTRS_PER_PGD (1 << PGD_INDEX_SIZE)
/*
* The normal case is that PTEs are 32-bits and we have a 1-page
* 1024-entry pgdir pointing to 1-page 1024-entry PTE pages. -- paulus
*
* For any >32-bit physical address platform, we can use the following
* two level page table layout where the pgdir is 8KB and the MS 13 bits
* are an index to the second level table. The combined pgdir/pmd first
* level has 2048 entries and the second level has 512 64-bit PTE entries.
* -Matt
*/
/* PGDIR_SHIFT determines what a top-level page table entry can map */
#define PGDIR_SHIFT (PAGE_SHIFT + PTE_INDEX_SIZE)
#define PGDIR_SIZE (1UL << PGDIR_SHIFT)
#define PGDIR_MASK (~(PGDIR_SIZE-1))
/* Bits to mask out from a PGD to get to the PUD page */
#define PGD_MASKED_BITS 0
#define USER_PTRS_PER_PGD (TASK_SIZE / PGDIR_SIZE)
#define pgd_ERROR(e) \
pr_err("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e))
/*
* This is the bottom of the PKMAP area with HIGHMEM or an arbitrary
* value (for now) on others, from where we can start layout kernel
* virtual space that goes below PKMAP and FIXMAP
*/
#define FIXADDR_SIZE 0
#ifdef CONFIG_KASAN
#include <asm/kasan.h>
#define FIXADDR_TOP (KASAN_SHADOW_START - PAGE_SIZE)
#else
#define FIXADDR_TOP ((unsigned long)(-PAGE_SIZE))
#endif
/*
* ioremap_bot starts at that address. Early ioremaps move down from there,
* until mem_init() at which point this becomes the top of the vmalloc
* and ioremap space
*/
#ifdef CONFIG_HIGHMEM
#define IOREMAP_TOP PKMAP_BASE
#else
#define IOREMAP_TOP FIXADDR_START
#endif
/* PPC32 shares vmalloc area with ioremap */
#define IOREMAP_START VMALLOC_START
#define IOREMAP_END VMALLOC_END
/*
* Just any arbitrary offset to the start of the vmalloc VM area: the
* current 16MB value just means that there will be a 64MB "hole" after the
* physical memory until the kernel virtual memory starts. That means that
* any out-of-bounds memory accesses will hopefully be caught.
* The vmalloc() routines leaves a hole of 4kB between each vmalloced
* area for the same reason. ;)
*
* We no longer map larger than phys RAM with the BATs so we don't have
* to worry about the VMALLOC_OFFSET causing problems. We do have to worry
* about clashes between our early calls to ioremap() that start growing down
* from IOREMAP_TOP being run into the VM area allocations (growing upwards
* from VMALLOC_START). For this reason we have ioremap_bot to check when
* we actually run into our mappings setup in the early boot with the VM
* system. This really does become a problem for machines with good amounts
* of RAM. -- Cort
*/
#define VMALLOC_OFFSET (0x1000000) /* 16M */
#ifdef PPC_PIN_SIZE
#define VMALLOC_START (((ALIGN((long)high_memory, PPC_PIN_SIZE) + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)))
#else
#define VMALLOC_START ((((long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)))
#endif
#ifdef CONFIG_KASAN_VMALLOC
#define VMALLOC_END ALIGN_DOWN(ioremap_bot, PAGE_SIZE << KASAN_SHADOW_SCALE_SHIFT)
#else
#define VMALLOC_END ioremap_bot
#endif
/*
* Bits in a linux-style PTE. These match the bits in the
* (hardware-defined) PowerPC PTE as closely as possible.
*/
#if defined(CONFIG_44x)
#include <asm/nohash/32/pte-44x.h>
#elif defined(CONFIG_PPC_85xx) && defined(CONFIG_PTE_64BIT)
#include <asm/nohash/pte-e500.h>
#elif defined(CONFIG_PPC_85xx)
#include <asm/nohash/32/pte-85xx.h>
#elif defined(CONFIG_PPC_8xx)
#include <asm/nohash/32/pte-8xx.h>
#endif
/*
* Location of the PFN in the PTE. Most 32-bit platforms use the same
* as _PAGE_SHIFT here (ie, naturally aligned).
* Platform who don't just pre-define the value so we don't override it here.
*/
#ifndef PTE_RPN_SHIFT
#define PTE_RPN_SHIFT (PAGE_SHIFT)
#endif
/*
* The mask covered by the RPN must be a ULL on 32-bit platforms with
* 64-bit PTEs.
*/
#ifdef CONFIG_PTE_64BIT
#define PTE_RPN_MASK (~((1ULL << PTE_RPN_SHIFT) - 1))
#define MAX_POSSIBLE_PHYSMEM_BITS 36
#else
#define PTE_RPN_MASK (~((1UL << PTE_RPN_SHIFT) - 1))
#define MAX_POSSIBLE_PHYSMEM_BITS 32
#endif
#ifndef __ASSEMBLY__
#define pmd_none(pmd) (!pmd_val(pmd))
#define pmd_bad(pmd) (pmd_val(pmd) & _PMD_BAD)
#define pmd_present(pmd) (pmd_val(pmd) & _PMD_PRESENT_MASK)
static inline void pmd_clear(pmd_t *pmdp)
{
*pmdp = __pmd(0);
}
/*
* Note that on Book E processors, the pmd contains the kernel virtual
* (lowmem) address of the pte page. The physical address is less useful
* because everything runs with translation enabled (even the TLB miss
* handler). On everything else the pmd contains the physical address
* of the pte page. -- paulus
*/
#ifndef CONFIG_BOOKE
#define pmd_pfn(pmd) (pmd_val(pmd) >> PAGE_SHIFT)
#else
#define pmd_page_vaddr(pmd) \
((const void *)(pmd_val(pmd) & ~(PTE_TABLE_SIZE - 1)))
#define pmd_pfn(pmd) (__pa(pmd_val(pmd)) >> PAGE_SHIFT)
#endif
#define pmd_page(pmd) pfn_to_page(pmd_pfn(pmd))
/*
* Encode/decode swap entries and swap PTEs. Swap PTEs are all PTEs that
* are !pte_none() && !pte_present().
*
* Format of swap PTEs (32bit PTEs):
*
* 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* <------------------ offset -------------------> < type -> E 0 0
*
* E is the exclusive marker that is not stored in swap entries.
*
* For 64bit PTEs, the offset is extended by 32bit.
*/
#define __swp_type(entry) ((entry).val & 0x1f)
#define __swp_offset(entry) ((entry).val >> 5)
#define __swp_entry(type, offset) ((swp_entry_t) { ((type) & 0x1f) | ((offset) << 5) })
#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) >> 3 })
#define __swp_entry_to_pte(x) ((pte_t) { (x).val << 3 })
/* We borrow LSB 2 to store the exclusive marker in swap PTEs. */
#define _PAGE_SWP_EXCLUSIVE 0x000004
#endif /* !__ASSEMBLY__ */
#endif /* __ASM_POWERPC_NOHASH_32_PGTABLE_H */
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