arch/powerpc/include/asm/mmu.h

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_POWERPC_MMU_H_
#define _ASM_POWERPC_MMU_H_
#ifdef __KERNEL__

#include <linux/types.h>

#include <asm/asm-const.h>

/*
 * MMU features bit definitions
 */

/*
 * MMU families
 */
#define MMU_FTR_HPTE_TABLE		ASM_CONST(0x00000001)
#define MMU_FTR_TYPE_8xx		ASM_CONST(0x00000002)
#define MMU_FTR_TYPE_40x		ASM_CONST(0x00000004)
#define MMU_FTR_TYPE_44x		ASM_CONST(0x00000008)
#define MMU_FTR_TYPE_FSL_E		ASM_CONST(0x00000010)
#define MMU_FTR_TYPE_47x		ASM_CONST(0x00000020)

/* Radix page table supported and enabled */
#define MMU_FTR_TYPE_RADIX		ASM_CONST(0x00000040)

/*
 * Individual features below.
 */

/*
 * Support for 68 bit VA space. We added that from ISA 2.05
 */
#define MMU_FTR_68_BIT_VA		ASM_CONST(0x00002000)
/*
 * Kernel read only support.
 * We added the ppp value 0b110 in ISA 2.04.
 */
#define MMU_FTR_KERNEL_RO		ASM_CONST(0x00004000)

/*
 * We need to clear top 16bits of va (from the remaining 64 bits )in
 * tlbie* instructions
 */
#define MMU_FTR_TLBIE_CROP_VA		ASM_CONST(0x00008000)

/* Enable use of high BAT registers */
#define MMU_FTR_USE_HIGH_BATS		ASM_CONST(0x00010000)

/* Enable >32-bit physical addresses on 32-bit processor, only used
 * by CONFIG_PPC_BOOK3S_32 currently as BookE supports that from day 1
 */
#define MMU_FTR_BIG_PHYS		ASM_CONST(0x00020000)

/* Enable use of broadcast TLB invalidations. We don't always set it
 * on processors that support it due to other constraints with the
 * use of such invalidations
 */
#define MMU_FTR_USE_TLBIVAX_BCAST	ASM_CONST(0x00040000)

/* Enable use of tlbilx invalidate instructions.
 */
#define MMU_FTR_USE_TLBILX		ASM_CONST(0x00080000)

/* This indicates that the processor cannot handle multiple outstanding
 * broadcast tlbivax or tlbsync. This makes the code use a spinlock
 * around such invalidate forms.
 */
#define MMU_FTR_LOCK_BCAST_INVAL	ASM_CONST(0x00100000)

/* This indicates that the processor doesn't handle way selection
 * properly and needs SW to track and update the LRU state.  This
 * is specific to an errata on e300c2/c3/c4 class parts
 */
#define MMU_FTR_NEED_DTLB_SW_LRU	ASM_CONST(0x00200000)

/* Enable use of TLB reservation.  Processor should support tlbsrx.
 * instruction and MAS0[WQ].
 */
#define MMU_FTR_USE_TLBRSRV		ASM_CONST(0x00800000)

/* Use paired MAS registers (MAS7||MAS3, etc.)
 */
#define MMU_FTR_USE_PAIRED_MAS		ASM_CONST(0x01000000)

/* Doesn't support the B bit (1T segment) in SLBIE
 */
#define MMU_FTR_NO_SLBIE_B		ASM_CONST(0x02000000)

/* Support 16M large pages
 */
#define MMU_FTR_16M_PAGE		ASM_CONST(0x04000000)

/* Supports TLBIEL variant
 */
#define MMU_FTR_TLBIEL			ASM_CONST(0x08000000)

/* Supports tlbies w/o locking
 */
#define MMU_FTR_LOCKLESS_TLBIE		ASM_CONST(0x10000000)

/* Large pages can be marked CI
 */
#define MMU_FTR_CI_LARGE_PAGE		ASM_CONST(0x20000000)

/* 1T segments available
 */
#define MMU_FTR_1T_SEGMENT		ASM_CONST(0x40000000)

/* MMU feature bit sets for various CPUs */
#define MMU_FTRS_DEFAULT_HPTE_ARCH_V2	\
	MMU_FTR_HPTE_TABLE | MMU_FTR_PPCAS_ARCH_V2
#define MMU_FTRS_POWER		MMU_FTRS_DEFAULT_HPTE_ARCH_V2
#define MMU_FTRS_PPC970		MMU_FTRS_POWER | MMU_FTR_TLBIE_CROP_VA
#define MMU_FTRS_POWER5		MMU_FTRS_POWER | MMU_FTR_LOCKLESS_TLBIE
#define MMU_FTRS_POWER6		MMU_FTRS_POWER5 | MMU_FTR_KERNEL_RO | MMU_FTR_68_BIT_VA
#define MMU_FTRS_POWER7		MMU_FTRS_POWER6
#define MMU_FTRS_POWER8		MMU_FTRS_POWER6
#define MMU_FTRS_POWER9		MMU_FTRS_POWER6
#define MMU_FTRS_CELL		MMU_FTRS_DEFAULT_HPTE_ARCH_V2 | \
				MMU_FTR_CI_LARGE_PAGE
#define MMU_FTRS_PA6T		MMU_FTRS_DEFAULT_HPTE_ARCH_V2 | \
				MMU_FTR_CI_LARGE_PAGE | MMU_FTR_NO_SLBIE_B
#ifndef __ASSEMBLY__
#include <linux/bug.h>
#include <asm/cputable.h>

#ifdef CONFIG_PPC_FSL_BOOK3E
#include <asm/percpu.h>
DECLARE_PER_CPU(int, next_tlbcam_idx);
#endif

enum {
	MMU_FTRS_POSSIBLE =
#ifdef CONFIG_PPC_BOOK3S
		MMU_FTR_HPTE_TABLE |
#endif
#ifdef CONFIG_PPC_8xx
		MMU_FTR_TYPE_8xx |
#endif
#ifdef CONFIG_40x
		MMU_FTR_TYPE_40x |
#endif
#ifdef CONFIG_44x
		MMU_FTR_TYPE_44x |
#endif
#if defined(CONFIG_E200) || defined(CONFIG_E500)
		MMU_FTR_TYPE_FSL_E | MMU_FTR_BIG_PHYS | MMU_FTR_USE_TLBILX |
#endif
#ifdef CONFIG_PPC_47x
		MMU_FTR_TYPE_47x | MMU_FTR_USE_TLBIVAX_BCAST | MMU_FTR_LOCK_BCAST_INVAL |
#endif
#ifdef CONFIG_PPC_BOOK3S_32
		MMU_FTR_USE_HIGH_BATS | MMU_FTR_NEED_DTLB_SW_LRU |
#endif
#ifdef CONFIG_PPC_BOOK3E_64
		MMU_FTR_USE_TLBRSRV | MMU_FTR_USE_PAIRED_MAS |
#endif
#ifdef CONFIG_PPC_BOOK3S_64
		MMU_FTR_NO_SLBIE_B | MMU_FTR_16M_PAGE | MMU_FTR_TLBIEL |
		MMU_FTR_LOCKLESS_TLBIE | MMU_FTR_CI_LARGE_PAGE |
		MMU_FTR_1T_SEGMENT | MMU_FTR_TLBIE_CROP_VA |
		MMU_FTR_KERNEL_RO | MMU_FTR_68_BIT_VA |
#endif
#ifdef CONFIG_PPC_RADIX_MMU
		MMU_FTR_TYPE_RADIX |
#endif
		0,
};

static inline bool early_mmu_has_feature(unsigned long feature)
{
	return !!(MMU_FTRS_POSSIBLE & cur_cpu_spec->mmu_features & feature);
}

#ifdef CONFIG_JUMP_LABEL_FEATURE_CHECKS
#include <linux/jump_label.h>

#define NUM_MMU_FTR_KEYS	32

extern struct static_key_true mmu_feature_keys[NUM_MMU_FTR_KEYS];

extern void mmu_feature_keys_init(void);

static __always_inline bool mmu_has_feature(unsigned long feature)
{
	int i;

#ifndef __clang__ /* clang can't cope with this */
	BUILD_BUG_ON(!__builtin_constant_p(feature));
#endif

#ifdef CONFIG_JUMP_LABEL_FEATURE_CHECK_DEBUG
	if (!static_key_initialized) {
		printk("Warning! mmu_has_feature() used prior to jump label init!\n");
		dump_stack();
		return early_mmu_has_feature(feature);
	}
#endif

	if (!(MMU_FTRS_POSSIBLE & feature))
		return false;

	i = __builtin_ctzl(feature);
	return static_branch_likely(&mmu_feature_keys[i]);
}

static inline void mmu_clear_feature(unsigned long feature)
{
	int i;

	i = __builtin_ctzl(feature);
	cur_cpu_spec->mmu_features &= ~feature;
	static_branch_disable(&mmu_feature_keys[i]);
}
#else

static inline void mmu_feature_keys_init(void)
{

}

static inline bool mmu_has_feature(unsigned long feature)
{
	return early_mmu_has_feature(feature);
}

static inline void mmu_clear_feature(unsigned long feature)
{
	cur_cpu_spec->mmu_features &= ~feature;
}
#endif /* CONFIG_JUMP_LABEL */

extern unsigned int __start___mmu_ftr_fixup, __stop___mmu_ftr_fixup;

#ifdef CONFIG_PPC64
/* This is our real memory area size on ppc64 server, on embedded, we
 * make it match the size our of bolted TLB area
 */
extern u64 ppc64_rma_size;

/* Cleanup function used by kexec */
extern void mmu_cleanup_all(void);
extern void radix__mmu_cleanup_all(void);

/* Functions for creating and updating partition table on POWER9 */
extern void mmu_partition_table_init(void);
extern void mmu_partition_table_set_entry(unsigned int lpid, unsigned long dw0,
					  unsigned long dw1);
#endif /* CONFIG_PPC64 */

struct mm_struct;
#ifdef CONFIG_DEBUG_VM
extern void assert_pte_locked(struct mm_struct *mm, unsigned long addr);
#else /* CONFIG_DEBUG_VM */
static inline void assert_pte_locked(struct mm_struct *mm, unsigned long addr)
{
}
#endif /* !CONFIG_DEBUG_VM */

#ifdef CONFIG_PPC_RADIX_MMU
static inline bool radix_enabled(void)
{
	return mmu_has_feature(MMU_FTR_TYPE_RADIX);
}

static inline bool early_radix_enabled(void)
{
	return early_mmu_has_feature(MMU_FTR_TYPE_RADIX);
}
#else
static inline bool radix_enabled(void)
{
	return false;
}

static inline bool early_radix_enabled(void)
{
	return false;
}
#endif

#ifdef CONFIG_PPC_MEM_KEYS
extern u16 get_mm_addr_key(struct mm_struct *mm, unsigned long address);
#else
static inline u16 get_mm_addr_key(struct mm_struct *mm, unsigned long address)
{
	return 0;
}
#endif /* CONFIG_PPC_MEM_KEYS */

#ifdef CONFIG_STRICT_KERNEL_RWX
static inline bool strict_kernel_rwx_enabled(void)
{
	return rodata_enabled;
}
#else
static inline bool strict_kernel_rwx_enabled(void)
{
	return false;
}
#endif
#endif /* !__ASSEMBLY__ */

/* The kernel use the constants below to index in the page sizes array.
 * The use of fixed constants for this purpose is better for performances
 * of the low level hash refill handlers.
 *
 * A non supported page size has a "shift" field set to 0
 *
 * Any new page size being implemented can get a new entry in here. Whether
 * the kernel will use it or not is a different matter though. The actual page
 * size used by hugetlbfs is not defined here and may be made variable
 *
 * Note: This array ended up being a false good idea as it's growing to the
 * point where I wonder if we should replace it with something different,
 * to think about, feedback welcome. --BenH.
 */

/* These are #defines as they have to be used in assembly */
#define MMU_PAGE_4K	0
#define MMU_PAGE_16K	1
#define MMU_PAGE_64K	2
#define MMU_PAGE_64K_AP	3	/* "Admixed pages" (hash64 only) */
#define MMU_PAGE_256K	4
#define MMU_PAGE_512K	5
#define MMU_PAGE_1M	6
#define MMU_PAGE_2M	7
#define MMU_PAGE_4M	8
#define MMU_PAGE_8M	9
#define MMU_PAGE_16M	10
#define MMU_PAGE_64M	11
#define MMU_PAGE_256M	12
#define MMU_PAGE_1G	13
#define MMU_PAGE_16G	14
#define MMU_PAGE_64G	15

/*
 * N.B. we need to change the type of hpte_page_sizes if this gets to be > 16
 * Also we need to change he type of mm_context.low/high_slices_psize.
 */
#define MMU_PAGE_COUNT	16

/*
 * If we store section details in page->flags we can't increase the MAX_PHYSMEM_BITS
 * if we increase SECTIONS_WIDTH we will not store node details in page->flags and
 * page_to_nid does a page->section->node lookup
 * Hence only increase for VMEMMAP. Further depending on SPARSEMEM_EXTREME reduce
 * memory requirements with large number of sections.
 * 51 bits is the max physical real address on POWER9
 */
#if defined(CONFIG_SPARSEMEM_VMEMMAP) && defined(CONFIG_SPARSEMEM_EXTREME) &&	\
	defined (CONFIG_PPC_64K_PAGES)
#define MAX_PHYSMEM_BITS        51
#else
#define MAX_PHYSMEM_BITS        46
#endif

#ifdef CONFIG_PPC_BOOK3S_64
#include <asm/book3s/64/mmu.h>
#else /* CONFIG_PPC_BOOK3S_64 */

#ifndef __ASSEMBLY__
/* MMU initialization */
extern void early_init_mmu(void);
extern void early_init_mmu_secondary(void);
extern void setup_initial_memory_limit(phys_addr_t first_memblock_base,
				       phys_addr_t first_memblock_size);
static inline void mmu_early_init_devtree(void) { }

extern void *abatron_pteptrs[2];
#endif /* __ASSEMBLY__ */
#endif

#if defined(CONFIG_PPC_BOOK3S_32)
/* 32-bit classic hash table MMU */
#include <asm/book3s/32/mmu-hash.h>
#elif defined(CONFIG_PPC_MMU_NOHASH)
#include <asm/nohash/mmu.h>
#endif

#endif /* __KERNEL__ */
#endif /* _ASM_POWERPC_MMU_H_ */