// SPDX-License-Identifier: MIT
/*
 * Copyright © 2019 Intel Corporation
 */

#include "gen7_renderclear.h"
#include "i915_drv.h"
#include "intel_gpu_commands.h"

#define GT3_INLINE_DATA_DELAYS 0x1E00
#define batch_advance(Y, CS) GEM_BUG_ON((Y)->end != (CS))

struct cb_kernel {
        const void *data;
        u32 size;
};

#define CB_KERNEL(name) { .data = (name), .size = sizeof(name) }

#include "ivb_clear_kernel.c"
static const struct cb_kernel cb_kernel_ivb = CB_KERNEL(ivb_clear_kernel);

#include "hsw_clear_kernel.c"
static const struct cb_kernel cb_kernel_hsw = CB_KERNEL(hsw_clear_kernel);

struct batch_chunk {
        struct i915_vma *vma;
        u32 offset;
        u32 *start;
        u32 *end;
        u32 max_items;
};

struct batch_vals {
        u32 max_threads;
        u32 state_start;
        u32 surface_start;
        u32 surface_height;
        u32 surface_width;
        u32 size;
};

static int num_primitives(const struct batch_vals *bv)
{
        /*
         * We need to saturate the GPU with work in order to dispatch
         * a shader on every HW thread, and clear the thread-local registers.
         * In short, we have to dispatch work faster than the shaders can
         * run in order to fill the EU and occupy each HW thread.
         */
        return bv->max_threads;
}

static void
batch_get_defaults(struct drm_i915_private *i915, struct batch_vals *bv)
{
        if (IS_HASWELL(i915)) {
                switch (INTEL_INFO(i915)->gt) {
                default:
                case 1:
                        bv->max_threads = 70;
                        break;
                case 2:
                        bv->max_threads = 140;
                        break;
                case 3:
                        bv->max_threads = 280;
                        break;
                }
                bv->surface_height = 16 * 16;
                bv->surface_width = 32 * 2 * 16;
        } else {
                switch (INTEL_INFO(i915)->gt) {
                default:
                case 1: /* including vlv */
                        bv->max_threads = 36;
                        break;
                case 2:
                        bv->max_threads = 128;
                        break;
                }
                bv->surface_height = 16 * 8;
                bv->surface_width = 32 * 16;
        }
        bv->state_start = round_up(SZ_1K + num_primitives(bv) * 64, SZ_4K);
        bv->surface_start = bv->state_start + SZ_4K;
        bv->size = bv->surface_start + bv->surface_height * bv->surface_width;
}

static void batch_init(struct batch_chunk *bc,
                       struct i915_vma *vma,
                       u32 *start, u32 offset, u32 max_bytes)
{
        bc->vma = vma;
        bc->offset = offset;
        bc->start = start + bc->offset / sizeof(*bc->start);
        bc->end = bc->start;
        bc->max_items = max_bytes / sizeof(*bc->start);
}

static u32 batch_offset(const struct batch_chunk *bc, u32 *cs)
{
        return (cs - bc->start) * sizeof(*bc->start) + bc->offset;
}

static u32 batch_addr(const struct batch_chunk *bc)
{
        return bc->vma->node.start;
}

static void batch_add(struct batch_chunk *bc, const u32 d)
{
        GEM_BUG_ON((bc->end - bc->start) >= bc->max_items);
        *bc->end++ = d;
}

static u32 *batch_alloc_items(struct batch_chunk *bc, u32 align, u32 items)
{
        u32 *map;

        if (align) {
                u32 *end = PTR_ALIGN(bc->end, align);

                memset32(bc->end, 0, end - bc->end);
                bc->end = end;
        }

        map = bc->end;
        bc->end += items;

        return map;
}

static u32 *batch_alloc_bytes(struct batch_chunk *bc, u32 align, u32 bytes)
{
        GEM_BUG_ON(!IS_ALIGNED(bytes, sizeof(*bc->start)));
        return batch_alloc_items(bc, align, bytes / sizeof(*bc->start));
}

static u32
gen7_fill_surface_state(struct batch_chunk *state,
                        const u32 dst_offset,
                        const struct batch_vals *bv)
{
        u32 surface_h = bv->surface_height;
        u32 surface_w = bv->surface_width;
        u32 *cs = batch_alloc_items(state, 32, 8);
        u32 offset = batch_offset(state, cs);

#define SURFACE_2D 1
#define SURFACEFORMAT_B8G8R8A8_UNORM 0x0C0
#define RENDER_CACHE_READ_WRITE 1

        *cs++ = SURFACE_2D << 29 |
                (SURFACEFORMAT_B8G8R8A8_UNORM << 18) |
                (RENDER_CACHE_READ_WRITE << 8);

        *cs++ = batch_addr(state) + dst_offset;

        *cs++ = ((surface_h / 4 - 1) << 16) | (surface_w / 4 - 1);
        *cs++ = surface_w;
        *cs++ = 0;
        *cs++ = 0;
        *cs++ = 0;
#define SHADER_CHANNELS(r, g, b, a) \
        (((r) << 25) | ((g) << 22) | ((b) << 19) | ((a) << 16))
        *cs++ = SHADER_CHANNELS(4, 5, 6, 7);
        batch_advance(state, cs);

        return offset;
}

static u32
gen7_fill_binding_table(struct batch_chunk *state,
                        const struct batch_vals *bv)
{
        u32 surface_start =
                gen7_fill_surface_state(state, bv->surface_start, bv);
        u32 *cs = batch_alloc_items(state, 32, 8);
        u32 offset = batch_offset(state, cs);

        *cs++ = surface_start - state->offset;
        *cs++ = 0;
        *cs++ = 0;
        *cs++ = 0;
        *cs++ = 0;
        *cs++ = 0;
        *cs++ = 0;
        *cs++ = 0;
        batch_advance(state, cs);

        return offset;
}

static u32
gen7_fill_kernel_data(struct batch_chunk *state,
                      const u32 *data,
                      const u32 size)
{
        return batch_offset(state,
                            memcpy(batch_alloc_bytes(state, 64, size),
                                   data, size));
}

static u32
gen7_fill_interface_descriptor(struct batch_chunk *state,
                               const struct batch_vals *bv,
                               const struct cb_kernel *kernel,
                               unsigned int count)
{
        u32 kernel_offset =
                gen7_fill_kernel_data(state, kernel->data, kernel->size);
        u32 binding_table = gen7_fill_binding_table(state, bv);
        u32 *cs = batch_alloc_items(state, 32, 8 * count);
        u32 offset = batch_offset(state, cs);

        *cs++ = kernel_offset;
        *cs++ = (1 << 7) | (1 << 13);
        *cs++ = 0;
        *cs++ = (binding_table - state->offset) | 1;
        *cs++ = 0;
        *cs++ = 0;
        *cs++ = 0;
        *cs++ = 0;

        /* 1 - 63dummy idds */
        memset32(cs, 0x00, (count - 1) * 8);
        batch_advance(state, cs + (count - 1) * 8);

        return offset;
}

static void
gen7_emit_state_base_address(struct batch_chunk *batch,
                             u32 surface_state_base)
{
        u32 *cs = batch_alloc_items(batch, 0, 10);

        *cs++ = STATE_BASE_ADDRESS | (10 - 2);
        /* general */
        *cs++ = batch_addr(batch) | BASE_ADDRESS_MODIFY;
        /* surface */
        *cs++ = (batch_addr(batch) + surface_state_base) | BASE_ADDRESS_MODIFY;
        /* dynamic */
        *cs++ = batch_addr(batch) | BASE_ADDRESS_MODIFY;
        /* indirect */
        *cs++ = batch_addr(batch) | BASE_ADDRESS_MODIFY;
        /* instruction */
        *cs++ = batch_addr(batch) | BASE_ADDRESS_MODIFY;

        /* general/dynamic/indirect/instruction access Bound */
        *cs++ = 0;
        *cs++ = BASE_ADDRESS_MODIFY;
        *cs++ = 0;
        *cs++ = BASE_ADDRESS_MODIFY;
        batch_advance(batch, cs);
}

static void
gen7_emit_vfe_state(struct batch_chunk *batch,
                    const struct batch_vals *bv,
                    u32 urb_size, u32 curbe_size,
                    u32 mode)
{
        u32 threads = bv->max_threads - 1;
        u32 *cs = batch_alloc_items(batch, 32, 8);

        *cs++ = MEDIA_VFE_STATE | (8 - 2);

        /* scratch buffer */
        *cs++ = 0;

        /* number of threads & urb entries for GPGPU vs Media Mode */
        *cs++ = threads << 16 | 1 << 8 | mode << 2;

        *cs++ = 0;

        /* urb entry size & curbe size in 256 bits unit */
        *cs++ = urb_size << 16 | curbe_size;

        /* scoreboard */
        *cs++ = 0;
        *cs++ = 0;
        *cs++ = 0;
        batch_advance(batch, cs);
}

static void
gen7_emit_interface_descriptor_load(struct batch_chunk *batch,
                                    const u32 interface_descriptor,
                                    unsigned int count)
{
        u32 *cs = batch_alloc_items(batch, 8, 4);

        *cs++ = MEDIA_INTERFACE_DESCRIPTOR_LOAD | (4 - 2);
        *cs++ = 0;
        *cs++ = count * 8 * sizeof(*cs);

        /*
         * interface descriptor address - it is relative to the dynamics base
         * address
         */
        *cs++ = interface_descriptor;
        batch_advance(batch, cs);
}

static void
gen7_emit_media_object(struct batch_chunk *batch,
                       unsigned int media_object_index)
{
        unsigned int x_offset = (media_object_index % 16) * 64;
        unsigned int y_offset = (media_object_index / 16) * 16;
        unsigned int pkt = 6 + 3;
        u32 *cs;

        cs = batch_alloc_items(batch, 8, pkt);

        *cs++ = MEDIA_OBJECT | (pkt - 2);

        /* interface descriptor offset */
        *cs++ = 0;

        /* without indirect data */
        *cs++ = 0;
        *cs++ = 0;

        /* scoreboard */
        *cs++ = 0;
        *cs++ = 0;

        /* inline */
        *cs++ = y_offset << 16 | x_offset;
        *cs++ = 0;
        *cs++ = GT3_INLINE_DATA_DELAYS;

        batch_advance(batch, cs);
}

static void gen7_emit_pipeline_flush(struct batch_chunk *batch)
{
        u32 *cs = batch_alloc_items(batch, 0, 4);

        *cs++ = GFX_OP_PIPE_CONTROL(4);
        *cs++ = PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH |
                PIPE_CONTROL_DEPTH_CACHE_FLUSH |
                PIPE_CONTROL_DC_FLUSH_ENABLE |
                PIPE_CONTROL_CS_STALL;
        *cs++ = 0;
        *cs++ = 0;

        batch_advance(batch, cs);
}

static void gen7_emit_pipeline_invalidate(struct batch_chunk *batch)
{
        u32 *cs = batch_alloc_items(batch, 0, 10);

        /* ivb: Stall before STATE_CACHE_INVALIDATE */
        *cs++ = GFX_OP_PIPE_CONTROL(5);
        *cs++ = PIPE_CONTROL_STALL_AT_SCOREBOARD |
                PIPE_CONTROL_CS_STALL;
        *cs++ = 0;
        *cs++ = 0;
        *cs++ = 0;

        *cs++ = GFX_OP_PIPE_CONTROL(5);
        *cs++ = PIPE_CONTROL_STATE_CACHE_INVALIDATE;
        *cs++ = 0;
        *cs++ = 0;
        *cs++ = 0;

        batch_advance(batch, cs);
}

static void emit_batch(struct i915_vma * const vma,
                       u32 *start,
                       const struct batch_vals *bv)
{
        struct drm_i915_private *i915 = vma->vm->i915;
        const unsigned int desc_count = 1;
        const unsigned int urb_size = 1;
        struct batch_chunk cmds, state;
        u32 descriptors;
        unsigned int i;

        batch_init(&cmds, vma, start, 0, bv->state_start);
        batch_init(&state, vma, start, bv->state_start, SZ_4K);

        descriptors = gen7_fill_interface_descriptor(&state, bv,
                                                     IS_HASWELL(i915) ?
                                                     &cb_kernel_hsw :
                                                     &cb_kernel_ivb,
                                                     desc_count);

        /* Reset inherited context registers */
        gen7_emit_pipeline_flush(&cmds);
        gen7_emit_pipeline_invalidate(&cmds);
        batch_add(&cmds, MI_LOAD_REGISTER_IMM(2));
        batch_add(&cmds, i915_mmio_reg_offset(CACHE_MODE_0_GEN7));
        batch_add(&cmds, 0xffff0000 |
                        ((IS_IVB_GT1(i915) || IS_VALLEYVIEW(i915)) ?
                         HIZ_RAW_STALL_OPT_DISABLE :
                         0));
        batch_add(&cmds, i915_mmio_reg_offset(CACHE_MODE_1));
        batch_add(&cmds, 0xffff0000 | PIXEL_SUBSPAN_COLLECT_OPT_DISABLE);
        gen7_emit_pipeline_invalidate(&cmds);
        gen7_emit_pipeline_flush(&cmds);

        /* Switch to the media pipeline and our base address */
        gen7_emit_pipeline_invalidate(&cmds);
        batch_add(&cmds, PIPELINE_SELECT | PIPELINE_SELECT_MEDIA);
        batch_add(&cmds, MI_NOOP);
        gen7_emit_pipeline_invalidate(&cmds);

        gen7_emit_pipeline_flush(&cmds);
        gen7_emit_state_base_address(&cmds, descriptors);
        gen7_emit_pipeline_invalidate(&cmds);

        /* Set the clear-residual kernel state */
        gen7_emit_vfe_state(&cmds, bv, urb_size - 1, 0, 0);
        gen7_emit_interface_descriptor_load(&cmds, descriptors, desc_count);

        /* Execute the kernel on all HW threads */
        for (i = 0; i < num_primitives(bv); i++)
                gen7_emit_media_object(&cmds, i);

        batch_add(&cmds, MI_BATCH_BUFFER_END);
}

int gen7_setup_clear_gpr_bb(struct intel_engine_cs * const engine,
                            struct i915_vma * const vma)
{
        struct batch_vals bv;
        u32 *batch;

        batch_get_defaults(engine->i915, &bv);
        if (!vma)
                return bv.size;

        GEM_BUG_ON(vma->obj->base.size < bv.size);

        batch = i915_gem_object_pin_map(vma->obj, I915_MAP_WC);
        if (IS_ERR(batch))
                return PTR_ERR(batch);

        emit_batch(vma, memset(batch, 0, bv.size), &bv);

        i915_gem_object_flush_map(vma->obj);
        __i915_gem_object_release_map(vma->obj);

        return 0;
}