/*
 * Copyright © 2014 Intel Corporation
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 *
 * Please try to maintain the following order within this file unless it makes
 * sense to do otherwise. From top to bottom:
 * 1. typedefs
 * 2. #defines, and macros
 * 3. structure definitions
 * 4. function prototypes
 *
 * Within each section, please try to order by generation in ascending order,
 * from top to bottom (ie. gen6 on the top, gen8 on the bottom).
 */

#ifndef __I915_GEM_GTT_H__
#define __I915_GEM_GTT_H__

struct drm_i915_file_private;

typedef uint32_t gen6_pte_t;
typedef uint64_t gen8_pte_t;
typedef uint64_t gen8_pde_t;
typedef uint64_t gen8_ppgtt_pdpe_t;
typedef uint64_t gen8_ppgtt_pml4e_t;

#define gtt_total_entries(gtt) ((gtt).base.total >> PAGE_SHIFT)


/* gen6-hsw has bit 11-4 for physical addr bit 39-32 */
#define GEN6_GTT_ADDR_ENCODE(addr)      ((addr) | (((addr) >> 28) & 0xff0))
#define GEN6_PTE_ADDR_ENCODE(addr)      GEN6_GTT_ADDR_ENCODE(addr)
#define GEN6_PDE_ADDR_ENCODE(addr)      GEN6_GTT_ADDR_ENCODE(addr)
#define GEN6_PTE_CACHE_LLC              (2 << 1)
#define GEN6_PTE_UNCACHED               (1 << 1)
#define GEN6_PTE_VALID                  (1 << 0)

#define I915_PTES(pte_len)              (PAGE_SIZE / (pte_len))
#define I915_PTE_MASK(pte_len)          (I915_PTES(pte_len) - 1)
#define I915_PDES                       512
#define I915_PDE_MASK                   (I915_PDES - 1)
#define NUM_PTE(pde_shift)     (1 << (pde_shift - PAGE_SHIFT))

#define GEN6_PTES                       I915_PTES(sizeof(gen6_pte_t))
#define GEN6_PD_SIZE                    (I915_PDES * PAGE_SIZE)
#define GEN6_PD_ALIGN                   (PAGE_SIZE * 16)
#define GEN6_PDE_SHIFT                  22
#define GEN6_PDE_VALID                  (1 << 0)

#define GEN7_PTE_CACHE_L3_LLC           (3 << 1)

#define BYT_PTE_SNOOPED_BY_CPU_CACHES   (1 << 2)
#define BYT_PTE_WRITEABLE               (1 << 1)

/* Cacheability Control is a 4-bit value. The low three bits are stored in bits
 * 3:1 of the PTE, while the fourth bit is stored in bit 11 of the PTE.
 */
#define HSW_CACHEABILITY_CONTROL(bits)  ((((bits) & 0x7) << 1) | \
                                         (((bits) & 0x8) << (11 - 3)))
#define HSW_WB_LLC_AGE3                 HSW_CACHEABILITY_CONTROL(0x2)
#define HSW_WB_LLC_AGE0                 HSW_CACHEABILITY_CONTROL(0x3)
#define HSW_WB_ELLC_LLC_AGE3            HSW_CACHEABILITY_CONTROL(0x8)
#define HSW_WB_ELLC_LLC_AGE0            HSW_CACHEABILITY_CONTROL(0xb)
#define HSW_WT_ELLC_LLC_AGE3            HSW_CACHEABILITY_CONTROL(0x7)
#define HSW_WT_ELLC_LLC_AGE0            HSW_CACHEABILITY_CONTROL(0x6)
#define HSW_PTE_UNCACHED                (0)
#define HSW_GTT_ADDR_ENCODE(addr)       ((addr) | (((addr) >> 28) & 0x7f0))
#define HSW_PTE_ADDR_ENCODE(addr)       HSW_GTT_ADDR_ENCODE(addr)

/* GEN8 legacy style address is defined as a 3 level page table:
 * 31:30 | 29:21 | 20:12 |  11:0
 * PDPE  |  PDE  |  PTE  | offset
 * The difference as compared to normal x86 3 level page table is the PDPEs are
 * programmed via register.
 *
 * GEN8 48b legacy style address is defined as a 4 level page table:
 * 47:39 | 38:30 | 29:21 | 20:12 |  11:0
 * PML4E | PDPE  |  PDE  |  PTE  | offset
 */
#define GEN8_PML4ES_PER_PML4            512
#define GEN8_PML4E_SHIFT                39
#define GEN8_PML4E_MASK                 (GEN8_PML4ES_PER_PML4 - 1)
#define GEN8_PDPE_SHIFT                 30
/* NB: GEN8_PDPE_MASK is untrue for 32b platforms, but it has no impact on 32b page
 * tables */
#define GEN8_PDPE_MASK                  0x1ff
#define GEN8_PDE_SHIFT                  21
#define GEN8_PDE_MASK                   0x1ff
#define GEN8_PTE_SHIFT                  12
#define GEN8_PTE_MASK                   0x1ff
#define GEN8_LEGACY_PDPES               4
#define GEN8_PTES                       I915_PTES(sizeof(gen8_pte_t))

#define I915_PDPES_PER_PDP(dev) (USES_FULL_48BIT_PPGTT(dev) ?\
                                 GEN8_PML4ES_PER_PML4 : GEN8_LEGACY_PDPES)

#define PPAT_UNCACHED_INDEX             (_PAGE_PWT | _PAGE_PCD)
#define PPAT_CACHED_PDE_INDEX           0 /* WB LLC */
#define PPAT_CACHED_INDEX               _PAGE_PAT /* WB LLCeLLC */
#define PPAT_DISPLAY_ELLC_INDEX         _PAGE_PCD /* WT eLLC */

#define CHV_PPAT_SNOOP                  (1<<6)
#define GEN8_PPAT_AGE(x)                (x<<4)
#define GEN8_PPAT_LLCeLLC               (3<<2)
#define GEN8_PPAT_LLCELLC               (2<<2)
#define GEN8_PPAT_LLC                   (1<<2)
#define GEN8_PPAT_WB                    (3<<0)
#define GEN8_PPAT_WT                    (2<<0)
#define GEN8_PPAT_WC                    (1<<0)
#define GEN8_PPAT_UC                    (0<<0)
#define GEN8_PPAT_ELLC_OVERRIDE         (0<<2)
#define GEN8_PPAT(i, x)                 ((uint64_t) (x) << ((i) * 8))

enum i915_ggtt_view_type {
        I915_GGTT_VIEW_NORMAL = 0,
        I915_GGTT_VIEW_ROTATED,
        I915_GGTT_VIEW_PARTIAL,
};

struct intel_rotation_info {
        unsigned int height;
        unsigned int pitch;
        unsigned int uv_offset;
        uint32_t pixel_format;
        uint64_t fb_modifier;
        unsigned int width_pages, height_pages;
        uint64_t size;
        unsigned int width_pages_uv, height_pages_uv;
        uint64_t size_uv;
        unsigned int uv_start_page;
};

struct i915_ggtt_view {
        enum i915_ggtt_view_type type;

        union {
                struct {
                        u64 offset;
                        unsigned int size;
                } partial;
                struct intel_rotation_info rotation_info;
        } params;

        struct sg_table *pages;
};

extern const struct i915_ggtt_view i915_ggtt_view_normal;
extern const struct i915_ggtt_view i915_ggtt_view_rotated;

enum i915_cache_level;

/**
 * A VMA represents a GEM BO that is bound into an address space. Therefore, a
 * VMA's presence cannot be guaranteed before binding, or after unbinding the
 * object into/from the address space.
 *
 * To make things as simple as possible (ie. no refcounting), a VMA's lifetime
 * will always be <= an objects lifetime. So object refcounting should cover us.
 */
struct i915_vma {
        struct drm_mm_node node;
        struct drm_i915_gem_object *obj;
        struct i915_address_space *vm;

        /** Flags and address space this VMA is bound to */
#define GLOBAL_BIND     (1<<0)
#define LOCAL_BIND      (1<<1)
        unsigned int bound : 4;

        /**
         * Support different GGTT views into the same object.
         * This means there can be multiple VMA mappings per object and per VM.
         * i915_ggtt_view_type is used to distinguish between those entries.
         * The default one of zero (I915_GGTT_VIEW_NORMAL) is default and also
         * assumed in GEM functions which take no ggtt view parameter.
         */
        struct i915_ggtt_view ggtt_view;

        /** This object's place on the active/inactive lists */
        struct list_head mm_list;

        struct list_head vma_link; /* Link in the object's VMA list */

        /** This vma's place in the batchbuffer or on the eviction list */
        struct list_head exec_list;

        /**
         * Used for performing relocations during execbuffer insertion.
         */
        struct hlist_node exec_node;
        unsigned long exec_handle;
        struct drm_i915_gem_exec_object2 *exec_entry;

        /**
         * How many users have pinned this object in GTT space. The following
         * users can each hold at most one reference: pwrite/pread, execbuffer
         * (objects are not allowed multiple times for the same batchbuffer),
         * and the framebuffer code. When switching/pageflipping, the
         * framebuffer code has at most two buffers pinned per crtc.
         *
         * In the worst case this is 1 + 1 + 1 + 2*2 = 7. That would fit into 3
         * bits with absolutely no headroom. So use 4 bits. */
        unsigned int pin_count:4;
#define DRM_I915_GEM_OBJECT_MAX_PIN_COUNT 0xf
};

struct i915_page_dma {
        struct page *page;
        union {
                dma_addr_t daddr;

                /* For gen6/gen7 only. This is the offset in the GGTT
                 * where the page directory entries for PPGTT begin
                 */
                uint32_t ggtt_offset;
        };
};

#define px_base(px) (&(px)->base)
#define px_page(px) (px_base(px)->page)
#define px_dma(px) (px_base(px)->daddr)

struct i915_page_scratch {
        struct i915_page_dma base;
};

struct i915_page_table {
        struct i915_page_dma base;

        unsigned long *used_ptes;
};

struct i915_page_directory {
        struct i915_page_dma base;

        unsigned long *used_pdes;
        struct i915_page_table *page_table[I915_PDES]; /* PDEs */
};

struct i915_page_directory_pointer {
        struct i915_page_dma base;

        unsigned long *used_pdpes;
        struct i915_page_directory **page_directory;
};

struct i915_pml4 {
        struct i915_page_dma base;

        DECLARE_BITMAP(used_pml4es, GEN8_PML4ES_PER_PML4);
        struct i915_page_directory_pointer *pdps[GEN8_PML4ES_PER_PML4];
};

struct i915_address_space {
        struct drm_mm mm;
        struct drm_device *dev;
        struct list_head global_link;
        u64 start;              /* Start offset always 0 for dri2 */
        u64 total;              /* size addr space maps (ex. 2GB for ggtt) */

        struct i915_page_scratch *scratch_page;
        struct i915_page_table *scratch_pt;
        struct i915_page_directory *scratch_pd;
        struct i915_page_directory_pointer *scratch_pdp; /* GEN8+ & 48b PPGTT */

        /**
         * List of objects currently involved in rendering.
         *
         * Includes buffers having the contents of their GPU caches
         * flushed, not necessarily primitives. last_read_req
         * represents when the rendering involved will be completed.
         *
         * A reference is held on the buffer while on this list.
         */
        struct list_head active_list;

        /**
         * LRU list of objects which are not in the ringbuffer and
         * are ready to unbind, but are still in the GTT.
         *
         * last_read_req is NULL while an object is in this list.
         *
         * A reference is not held on the buffer while on this list,
         * as merely being GTT-bound shouldn't prevent its being
         * freed, and we'll pull it off the list in the free path.
         */
        struct list_head inactive_list;

        /* FIXME: Need a more generic return type */
        gen6_pte_t (*pte_encode)(dma_addr_t addr,
                                 enum i915_cache_level level,
                                 bool valid, u32 flags); /* Create a valid PTE */
        /* flags for pte_encode */
#define PTE_READ_ONLY   (1<<0)
        int (*allocate_va_range)(struct i915_address_space *vm,
                                 uint64_t start,
                                 uint64_t length);
        void (*clear_range)(struct i915_address_space *vm,
                            uint64_t start,
                            uint64_t length,
                            bool use_scratch);
        void (*insert_entries)(struct i915_address_space *vm,
                               struct sg_table *st,
                               uint64_t start,
                               enum i915_cache_level cache_level, u32 flags);
        void (*cleanup)(struct i915_address_space *vm);
        /** Unmap an object from an address space. This usually consists of
         * setting the valid PTE entries to a reserved scratch page. */
        void (*unbind_vma)(struct i915_vma *vma);
        /* Map an object into an address space with the given cache flags. */
        int (*bind_vma)(struct i915_vma *vma,
                        enum i915_cache_level cache_level,
                        u32 flags);
};

/* The Graphics Translation Table is the way in which GEN hardware translates a
 * Graphics Virtual Address into a Physical Address. In addition to the normal
 * collateral associated with any va->pa translations GEN hardware also has a
 * portion of the GTT which can be mapped by the CPU and remain both coherent
 * and correct (in cases like swizzling). That region is referred to as GMADR in
 * the spec.
 */
struct i915_gtt {
        struct i915_address_space base;

        size_t stolen_size;             /* Total size of stolen memory */
        size_t stolen_usable_size;      /* Total size minus BIOS reserved */
        u64 mappable_end;               /* End offset that we can CPU map */
        struct io_mapping *mappable;    /* Mapping to our CPU mappable region */
        phys_addr_t mappable_base;      /* PA of our GMADR */

        /** "Graphics Stolen Memory" holds the global PTEs */
        void __iomem *gsm;

        bool do_idle_maps;

        int mtrr;

        /* global gtt ops */
        int (*gtt_probe)(struct drm_device *dev, u64 *gtt_total,
                          size_t *stolen, phys_addr_t *mappable_base,
                          u64 *mappable_end);
};

struct i915_hw_ppgtt {
        struct i915_address_space base;
        struct kref ref;
        struct drm_mm_node node;
        unsigned long pd_dirty_rings;
        union {
                struct i915_pml4 pml4;          /* GEN8+ & 48b PPGTT */
                struct i915_page_directory_pointer pdp; /* GEN8+ */
                struct i915_page_directory pd;          /* GEN6-7 */
        };

        struct drm_i915_file_private *file_priv;

        gen6_pte_t __iomem *pd_addr;

        int (*enable)(struct i915_hw_ppgtt *ppgtt);
        int (*switch_mm)(struct i915_hw_ppgtt *ppgtt,
                         struct drm_i915_gem_request *req);
        void (*debug_dump)(struct i915_hw_ppgtt *ppgtt, struct seq_file *m);
};

/* For each pde iterates over every pde between from start until start + length.
 * If start, and start+length are not perfectly divisible, the macro will round
 * down, and up as needed. The macro modifies pde, start, and length. Dev is
 * only used to differentiate shift values. Temp is temp.  On gen6/7, start = 0,
 * and length = 2G effectively iterates over every PDE in the system.
 *
 * XXX: temp is not actually needed, but it saves doing the ALIGN operation.
 */
#define gen6_for_each_pde(pt, pd, start, length, temp, iter) \
        for (iter = gen6_pde_index(start); \
             length > 0 && iter < I915_PDES ? \
                        (pt = (pd)->page_table[iter]), 1 : 0; \
             iter++, \
             temp = ALIGN(start+1, 1 << GEN6_PDE_SHIFT) - start, \
             temp = min_t(unsigned, temp, length), \
             start += temp, length -= temp)

#define gen6_for_all_pdes(pt, ppgtt, iter)  \
        for (iter = 0;          \
             pt = ppgtt->pd.page_table[iter], iter < I915_PDES; \
             iter++)

static inline uint32_t i915_pte_index(uint64_t address, uint32_t pde_shift)
{
        const uint32_t mask = NUM_PTE(pde_shift) - 1;

        return (address >> PAGE_SHIFT) & mask;
}

/* Helper to counts the number of PTEs within the given length. This count
 * does not cross a page table boundary, so the max value would be
 * GEN6_PTES for GEN6, and GEN8_PTES for GEN8.
*/
static inline uint32_t i915_pte_count(uint64_t addr, size_t length,
                                      uint32_t pde_shift)
{
        const uint64_t mask = ~((1 << pde_shift) - 1);
        uint64_t end;

        WARN_ON(length == 0);
        WARN_ON(offset_in_page(addr|length));

        end = addr + length;

        if ((addr & mask) != (end & mask))
                return NUM_PTE(pde_shift) - i915_pte_index(addr, pde_shift);

        return i915_pte_index(end, pde_shift) - i915_pte_index(addr, pde_shift);
}

static inline uint32_t i915_pde_index(uint64_t addr, uint32_t shift)
{
        return (addr >> shift) & I915_PDE_MASK;
}

static inline uint32_t gen6_pte_index(uint32_t addr)
{
        return i915_pte_index(addr, GEN6_PDE_SHIFT);
}

static inline size_t gen6_pte_count(uint32_t addr, uint32_t length)
{
        return i915_pte_count(addr, length, GEN6_PDE_SHIFT);
}

static inline uint32_t gen6_pde_index(uint32_t addr)
{
        return i915_pde_index(addr, GEN6_PDE_SHIFT);
}

/* Equivalent to the gen6 version, For each pde iterates over every pde
 * between from start until start + length. On gen8+ it simply iterates
 * over every page directory entry in a page directory.
 */
#define gen8_for_each_pde(pt, pd, start, length, iter)                  \
        for (iter = gen8_pde_index(start);                              \
             length > 0 && iter < I915_PDES &&                          \
                (pt = (pd)->page_table[iter], true);                    \
             ({ u64 temp = ALIGN(start+1, 1 << GEN8_PDE_SHIFT);         \
                    temp = min(temp - start, length);                   \
                    start += temp, length -= temp; }), ++iter)

#define gen8_for_each_pdpe(pd, pdp, start, length, iter)                \
        for (iter = gen8_pdpe_index(start);                             \
             length > 0 && iter < I915_PDPES_PER_PDP(dev) &&            \
                (pd = (pdp)->page_directory[iter], true);               \
             ({ u64 temp = ALIGN(start+1, 1 << GEN8_PDPE_SHIFT);        \
                    temp = min(temp - start, length);                   \
                    start += temp, length -= temp; }), ++iter)

#define gen8_for_each_pml4e(pdp, pml4, start, length, iter)             \
        for (iter = gen8_pml4e_index(start);                            \
             length > 0 && iter < GEN8_PML4ES_PER_PML4 &&               \
                (pdp = (pml4)->pdps[iter], true);                       \
             ({ u64 temp = ALIGN(start+1, 1ULL << GEN8_PML4E_SHIFT);    \
                    temp = min(temp - start, length);                   \
                    start += temp, length -= temp; }), ++iter)

static inline uint32_t gen8_pte_index(uint64_t address)
{
        return i915_pte_index(address, GEN8_PDE_SHIFT);
}

static inline uint32_t gen8_pde_index(uint64_t address)
{
        return i915_pde_index(address, GEN8_PDE_SHIFT);
}

static inline uint32_t gen8_pdpe_index(uint64_t address)
{
        return (address >> GEN8_PDPE_SHIFT) & GEN8_PDPE_MASK;
}

static inline uint32_t gen8_pml4e_index(uint64_t address)
{
        return (address >> GEN8_PML4E_SHIFT) & GEN8_PML4E_MASK;
}

static inline size_t gen8_pte_count(uint64_t address, uint64_t length)
{
        return i915_pte_count(address, length, GEN8_PDE_SHIFT);
}

static inline dma_addr_t
i915_page_dir_dma_addr(const struct i915_hw_ppgtt *ppgtt, const unsigned n)
{
        return test_bit(n, ppgtt->pdp.used_pdpes) ?
                px_dma(ppgtt->pdp.page_directory[n]) :
                px_dma(ppgtt->base.scratch_pd);
}

int i915_gem_gtt_init(struct drm_device *dev);
void i915_gem_init_global_gtt(struct drm_device *dev);
void i915_global_gtt_cleanup(struct drm_device *dev);


int i915_ppgtt_init(struct drm_device *dev, struct i915_hw_ppgtt *ppgtt);
int i915_ppgtt_init_hw(struct drm_device *dev);
int i915_ppgtt_init_ring(struct drm_i915_gem_request *req);
void i915_ppgtt_release(struct kref *kref);
struct i915_hw_ppgtt *i915_ppgtt_create(struct drm_device *dev,
                                        struct drm_i915_file_private *fpriv);
static inline void i915_ppgtt_get(struct i915_hw_ppgtt *ppgtt)
{
        if (ppgtt)
                kref_get(&ppgtt->ref);
}
static inline void i915_ppgtt_put(struct i915_hw_ppgtt *ppgtt)
{
        if (ppgtt)
                kref_put(&ppgtt->ref, i915_ppgtt_release);
}

void i915_check_and_clear_faults(struct drm_device *dev);
void i915_gem_suspend_gtt_mappings(struct drm_device *dev);
void i915_gem_restore_gtt_mappings(struct drm_device *dev);

int __must_check i915_gem_gtt_prepare_object(struct drm_i915_gem_object *obj);
void i915_gem_gtt_finish_object(struct drm_i915_gem_object *obj);

static inline bool
i915_ggtt_view_equal(const struct i915_ggtt_view *a,
                     const struct i915_ggtt_view *b)
{
        if (WARN_ON(!a || !b))
                return false;

        if (a->type != b->type)
                return false;
        if (a->type != I915_GGTT_VIEW_NORMAL)
                return !memcmp(&a->params, &b->params, sizeof(a->params));
        return true;
}

size_t
i915_ggtt_view_size(struct drm_i915_gem_object *obj,
                    const struct i915_ggtt_view *view);

#endif