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linux-sg2042/drivers/gpu/drm/vc4/vc4_render_cl.c

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/*
* Copyright © 2014-2015 Broadcom
*
* 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.
*/
/**
* DOC: Render command list generation
*
* In the V3D hardware, render command lists are what load and store
* tiles of a framebuffer and optionally call out to binner-generated
* command lists to do the 3D drawing for that tile.
*
* In the VC4 driver, render command list generation is performed by the
* kernel instead of userspace. We do this because validating a
* user-submitted command list is hard to get right and has high CPU overhead,
* while the number of valid configurations for render command lists is
* actually fairly low.
*/
#include "uapi/drm/vc4_drm.h"
#include "vc4_drv.h"
#include "vc4_packet.h"
struct vc4_rcl_setup {
struct drm_gem_cma_object *color_read;
struct drm_gem_cma_object *color_write;
struct drm_gem_cma_object *zs_read;
struct drm_gem_cma_object *zs_write;
struct drm_gem_cma_object *msaa_color_write;
struct drm_gem_cma_object *msaa_zs_write;
struct drm_gem_cma_object *rcl;
u32 next_offset;
u32 next_write_bo_index;
};
static inline void rcl_u8(struct vc4_rcl_setup *setup, u8 val)
{
*(u8 *)(setup->rcl->vaddr + setup->next_offset) = val;
setup->next_offset += 1;
}
static inline void rcl_u16(struct vc4_rcl_setup *setup, u16 val)
{
*(u16 *)(setup->rcl->vaddr + setup->next_offset) = val;
setup->next_offset += 2;
}
static inline void rcl_u32(struct vc4_rcl_setup *setup, u32 val)
{
*(u32 *)(setup->rcl->vaddr + setup->next_offset) = val;
setup->next_offset += 4;
}
/*
* Emits a no-op STORE_TILE_BUFFER_GENERAL.
*
* If we emit a PACKET_TILE_COORDINATES, it must be followed by a store of
* some sort before another load is triggered.
*/
static void vc4_store_before_load(struct vc4_rcl_setup *setup)
{
rcl_u8(setup, VC4_PACKET_STORE_TILE_BUFFER_GENERAL);
rcl_u16(setup,
VC4_SET_FIELD(VC4_LOADSTORE_TILE_BUFFER_NONE,
VC4_LOADSTORE_TILE_BUFFER_BUFFER) |
VC4_STORE_TILE_BUFFER_DISABLE_COLOR_CLEAR |
VC4_STORE_TILE_BUFFER_DISABLE_ZS_CLEAR |
VC4_STORE_TILE_BUFFER_DISABLE_VG_MASK_CLEAR);
rcl_u32(setup, 0); /* no address, since we're in None mode */
}
/*
* Calculates the physical address of the start of a tile in a RCL surface.
*
* Unlike the other load/store packets,
* VC4_PACKET_LOAD/STORE_FULL_RES_TILE_BUFFER don't look at the tile
* coordinates packet, and instead just store to the address given.
*/
static uint32_t vc4_full_res_offset(struct vc4_exec_info *exec,
struct drm_gem_cma_object *bo,
struct drm_vc4_submit_rcl_surface *surf,
uint8_t x, uint8_t y)
{
return bo->paddr + surf->offset + VC4_TILE_BUFFER_SIZE *
(DIV_ROUND_UP(exec->args->width, 32) * y + x);
}
/*
* Emits a PACKET_TILE_COORDINATES if one isn't already pending.
*
* The tile coordinates packet triggers a pending load if there is one, are
* used for clipping during rendering, and determine where loads/stores happen
* relative to their base address.
*/
static void vc4_tile_coordinates(struct vc4_rcl_setup *setup,
uint32_t x, uint32_t y)
{
rcl_u8(setup, VC4_PACKET_TILE_COORDINATES);
rcl_u8(setup, x);
rcl_u8(setup, y);
}
static void emit_tile(struct vc4_exec_info *exec,
struct vc4_rcl_setup *setup,
uint8_t x, uint8_t y, bool first, bool last)
{
struct drm_vc4_submit_cl *args = exec->args;
bool has_bin = args->bin_cl_size != 0;
/* Note that the load doesn't actually occur until the
* tile coords packet is processed, and only one load
* may be outstanding at a time.
*/
if (setup->color_read) {
if (args->color_read.flags &
VC4_SUBMIT_RCL_SURFACE_READ_IS_FULL_RES) {
rcl_u8(setup, VC4_PACKET_LOAD_FULL_RES_TILE_BUFFER);
rcl_u32(setup,
vc4_full_res_offset(exec, setup->color_read,
&args->color_read, x, y) |
VC4_LOADSTORE_FULL_RES_DISABLE_ZS);
} else {
rcl_u8(setup, VC4_PACKET_LOAD_TILE_BUFFER_GENERAL);
rcl_u16(setup, args->color_read.bits);
rcl_u32(setup, setup->color_read->paddr +
args->color_read.offset);
}
}
if (setup->zs_read) {
if (args->zs_read.flags &
VC4_SUBMIT_RCL_SURFACE_READ_IS_FULL_RES) {
rcl_u8(setup, VC4_PACKET_LOAD_FULL_RES_TILE_BUFFER);
rcl_u32(setup,
vc4_full_res_offset(exec, setup->zs_read,
&args->zs_read, x, y) |
VC4_LOADSTORE_FULL_RES_DISABLE_COLOR);
} else {
if (setup->color_read) {
/* Exec previous load. */
vc4_tile_coordinates(setup, x, y);
vc4_store_before_load(setup);
}
rcl_u8(setup, VC4_PACKET_LOAD_TILE_BUFFER_GENERAL);
rcl_u16(setup, args->zs_read.bits);
rcl_u32(setup, setup->zs_read->paddr +
args->zs_read.offset);
}
}
/* Clipping depends on tile coordinates having been
* emitted, so we always need one here.
*/
vc4_tile_coordinates(setup, x, y);
/* Wait for the binner before jumping to the first
* tile's lists.
*/
if (first && has_bin)
rcl_u8(setup, VC4_PACKET_WAIT_ON_SEMAPHORE);
if (has_bin) {
rcl_u8(setup, VC4_PACKET_BRANCH_TO_SUB_LIST);
rcl_u32(setup, (exec->tile_alloc_offset +
(y * exec->bin_tiles_x + x) * 32));
}
if (setup->msaa_color_write) {
bool last_tile_write = (!setup->msaa_zs_write &&
!setup->zs_write &&
!setup->color_write);
uint32_t bits = VC4_LOADSTORE_FULL_RES_DISABLE_ZS;
if (!last_tile_write)
bits |= VC4_LOADSTORE_FULL_RES_DISABLE_CLEAR_ALL;
else if (last)
bits |= VC4_LOADSTORE_FULL_RES_EOF;
rcl_u8(setup, VC4_PACKET_STORE_FULL_RES_TILE_BUFFER);
rcl_u32(setup,
vc4_full_res_offset(exec, setup->msaa_color_write,
&args->msaa_color_write, x, y) |
bits);
}
if (setup->msaa_zs_write) {
bool last_tile_write = (!setup->zs_write &&
!setup->color_write);
uint32_t bits = VC4_LOADSTORE_FULL_RES_DISABLE_COLOR;
if (setup->msaa_color_write)
vc4_tile_coordinates(setup, x, y);
if (!last_tile_write)
bits |= VC4_LOADSTORE_FULL_RES_DISABLE_CLEAR_ALL;
else if (last)
bits |= VC4_LOADSTORE_FULL_RES_EOF;
rcl_u8(setup, VC4_PACKET_STORE_FULL_RES_TILE_BUFFER);
rcl_u32(setup,
vc4_full_res_offset(exec, setup->msaa_zs_write,
&args->msaa_zs_write, x, y) |
bits);
}
if (setup->zs_write) {
bool last_tile_write = !setup->color_write;
if (setup->msaa_color_write || setup->msaa_zs_write)
vc4_tile_coordinates(setup, x, y);
rcl_u8(setup, VC4_PACKET_STORE_TILE_BUFFER_GENERAL);
rcl_u16(setup, args->zs_write.bits |
(last_tile_write ?
0 : VC4_STORE_TILE_BUFFER_DISABLE_COLOR_CLEAR));
rcl_u32(setup,
(setup->zs_write->paddr + args->zs_write.offset) |
((last && last_tile_write) ?
VC4_LOADSTORE_TILE_BUFFER_EOF : 0));
}
if (setup->color_write) {
if (setup->msaa_color_write || setup->msaa_zs_write ||
setup->zs_write) {
vc4_tile_coordinates(setup, x, y);
}
if (last)
rcl_u8(setup, VC4_PACKET_STORE_MS_TILE_BUFFER_AND_EOF);
else
rcl_u8(setup, VC4_PACKET_STORE_MS_TILE_BUFFER);
}
}
static int vc4_create_rcl_bo(struct drm_device *dev, struct vc4_exec_info *exec,
struct vc4_rcl_setup *setup)
{
struct drm_vc4_submit_cl *args = exec->args;
bool has_bin = args->bin_cl_size != 0;
uint8_t min_x_tile = args->min_x_tile;
uint8_t min_y_tile = args->min_y_tile;
uint8_t max_x_tile = args->max_x_tile;
uint8_t max_y_tile = args->max_y_tile;
uint8_t xtiles = max_x_tile - min_x_tile + 1;
uint8_t ytiles = max_y_tile - min_y_tile + 1;
uint8_t xi, yi;
uint32_t size, loop_body_size;
bool positive_x = true;
bool positive_y = true;
if (args->flags & VC4_SUBMIT_CL_FIXED_RCL_ORDER) {
if (!(args->flags & VC4_SUBMIT_CL_RCL_ORDER_INCREASING_X))
positive_x = false;
if (!(args->flags & VC4_SUBMIT_CL_RCL_ORDER_INCREASING_Y))
positive_y = false;
}
size = VC4_PACKET_TILE_RENDERING_MODE_CONFIG_SIZE;
loop_body_size = VC4_PACKET_TILE_COORDINATES_SIZE;
if (args->flags & VC4_SUBMIT_CL_USE_CLEAR_COLOR) {
size += VC4_PACKET_CLEAR_COLORS_SIZE +
VC4_PACKET_TILE_COORDINATES_SIZE +
VC4_PACKET_STORE_TILE_BUFFER_GENERAL_SIZE;
}
if (setup->color_read) {
if (args->color_read.flags &
VC4_SUBMIT_RCL_SURFACE_READ_IS_FULL_RES) {
loop_body_size += VC4_PACKET_LOAD_FULL_RES_TILE_BUFFER_SIZE;
} else {
loop_body_size += VC4_PACKET_LOAD_TILE_BUFFER_GENERAL_SIZE;
}
}
if (setup->zs_read) {
if (args->zs_read.flags &
VC4_SUBMIT_RCL_SURFACE_READ_IS_FULL_RES) {
loop_body_size += VC4_PACKET_LOAD_FULL_RES_TILE_BUFFER_SIZE;
} else {
if (setup->color_read &&
!(args->color_read.flags &
VC4_SUBMIT_RCL_SURFACE_READ_IS_FULL_RES)) {
loop_body_size += VC4_PACKET_TILE_COORDINATES_SIZE;
loop_body_size += VC4_PACKET_STORE_TILE_BUFFER_GENERAL_SIZE;
}
loop_body_size += VC4_PACKET_LOAD_TILE_BUFFER_GENERAL_SIZE;
}
}
if (has_bin) {
size += VC4_PACKET_WAIT_ON_SEMAPHORE_SIZE;
loop_body_size += VC4_PACKET_BRANCH_TO_SUB_LIST_SIZE;
}
if (setup->msaa_color_write)
loop_body_size += VC4_PACKET_STORE_FULL_RES_TILE_BUFFER_SIZE;
if (setup->msaa_zs_write)
loop_body_size += VC4_PACKET_STORE_FULL_RES_TILE_BUFFER_SIZE;
if (setup->zs_write)
loop_body_size += VC4_PACKET_STORE_TILE_BUFFER_GENERAL_SIZE;
if (setup->color_write)
loop_body_size += VC4_PACKET_STORE_MS_TILE_BUFFER_SIZE;
/* We need a VC4_PACKET_TILE_COORDINATES in between each store. */
loop_body_size += VC4_PACKET_TILE_COORDINATES_SIZE *
((setup->msaa_color_write != NULL) +
(setup->msaa_zs_write != NULL) +
(setup->color_write != NULL) +
(setup->zs_write != NULL) - 1);
size += xtiles * ytiles * loop_body_size;
setup->rcl = &vc4_bo_create(dev, size, true, VC4_BO_TYPE_RCL)->base;
if (IS_ERR(setup->rcl))
return PTR_ERR(setup->rcl);
list_add_tail(&to_vc4_bo(&setup->rcl->base)->unref_head,
&exec->unref_list);
/* The tile buffer gets cleared when the previous tile is stored. If
* the clear values changed between frames, then the tile buffer has
* stale clear values in it, so we have to do a store in None mode (no
* writes) so that we trigger the tile buffer clear.
*/
if (args->flags & VC4_SUBMIT_CL_USE_CLEAR_COLOR) {
rcl_u8(setup, VC4_PACKET_CLEAR_COLORS);
rcl_u32(setup, args->clear_color[0]);
rcl_u32(setup, args->clear_color[1]);
rcl_u32(setup, args->clear_z);
rcl_u8(setup, args->clear_s);
vc4_tile_coordinates(setup, 0, 0);
rcl_u8(setup, VC4_PACKET_STORE_TILE_BUFFER_GENERAL);
rcl_u16(setup, VC4_LOADSTORE_TILE_BUFFER_NONE);
rcl_u32(setup, 0); /* no address, since we're in None mode */
}
rcl_u8(setup, VC4_PACKET_TILE_RENDERING_MODE_CONFIG);
rcl_u32(setup,
(setup->color_write ? (setup->color_write->paddr +
args->color_write.offset) :
0));
rcl_u16(setup, args->width);
rcl_u16(setup, args->height);
rcl_u16(setup, args->color_write.bits);
for (yi = 0; yi < ytiles; yi++) {
int y = positive_y ? min_y_tile + yi : max_y_tile - yi;
for (xi = 0; xi < xtiles; xi++) {
int x = positive_x ? min_x_tile + xi : max_x_tile - xi;
bool first = (xi == 0 && yi == 0);
bool last = (xi == xtiles - 1 && yi == ytiles - 1);
emit_tile(exec, setup, x, y, first, last);
}
}
BUG_ON(setup->next_offset != size);
exec->ct1ca = setup->rcl->paddr;
exec->ct1ea = setup->rcl->paddr + setup->next_offset;
return 0;
}
static int vc4_full_res_bounds_check(struct vc4_exec_info *exec,
struct drm_gem_cma_object *obj,
struct drm_vc4_submit_rcl_surface *surf)
{
struct drm_vc4_submit_cl *args = exec->args;
u32 render_tiles_stride = DIV_ROUND_UP(exec->args->width, 32);
if (surf->offset > obj->base.size) {
DRM_DEBUG("surface offset %d > BO size %zd\n",
surf->offset, obj->base.size);
return -EINVAL;
}
if ((obj->base.size - surf->offset) / VC4_TILE_BUFFER_SIZE <
render_tiles_stride * args->max_y_tile + args->max_x_tile) {
DRM_DEBUG("MSAA tile %d, %d out of bounds "
"(bo size %zd, offset %d).\n",
args->max_x_tile, args->max_y_tile,
obj->base.size,
surf->offset);
return -EINVAL;
}
return 0;
}
static int vc4_rcl_msaa_surface_setup(struct vc4_exec_info *exec,
struct drm_gem_cma_object **obj,
struct drm_vc4_submit_rcl_surface *surf)
{
if (surf->flags != 0 || surf->bits != 0) {
DRM_DEBUG("MSAA surface had nonzero flags/bits\n");
return -EINVAL;
}
if (surf->hindex == ~0)
return 0;
*obj = vc4_use_bo(exec, surf->hindex);
if (!*obj)
return -EINVAL;
exec->rcl_write_bo[exec->rcl_write_bo_count++] = *obj;
if (surf->offset & 0xf) {
DRM_DEBUG("MSAA write must be 16b aligned.\n");
return -EINVAL;
}
return vc4_full_res_bounds_check(exec, *obj, surf);
}
static int vc4_rcl_surface_setup(struct vc4_exec_info *exec,
struct drm_gem_cma_object **obj,
struct drm_vc4_submit_rcl_surface *surf,
bool is_write)
{
uint8_t tiling = VC4_GET_FIELD(surf->bits,
VC4_LOADSTORE_TILE_BUFFER_TILING);
uint8_t buffer = VC4_GET_FIELD(surf->bits,
VC4_LOADSTORE_TILE_BUFFER_BUFFER);
uint8_t format = VC4_GET_FIELD(surf->bits,
VC4_LOADSTORE_TILE_BUFFER_FORMAT);
int cpp;
int ret;
if (surf->flags & ~VC4_SUBMIT_RCL_SURFACE_READ_IS_FULL_RES) {
DRM_DEBUG("Extra flags set\n");
return -EINVAL;
}
if (surf->hindex == ~0)
return 0;
*obj = vc4_use_bo(exec, surf->hindex);
if (!*obj)
return -EINVAL;
if (is_write)
exec->rcl_write_bo[exec->rcl_write_bo_count++] = *obj;
if (surf->flags & VC4_SUBMIT_RCL_SURFACE_READ_IS_FULL_RES) {
if (surf == &exec->args->zs_write) {
DRM_DEBUG("general zs write may not be a full-res.\n");
return -EINVAL;
}
if (surf->bits != 0) {
DRM_DEBUG("load/store general bits set with "
"full res load/store.\n");
return -EINVAL;
}
ret = vc4_full_res_bounds_check(exec, *obj, surf);
if (ret)
return ret;
return 0;
}
if (surf->bits & ~(VC4_LOADSTORE_TILE_BUFFER_TILING_MASK |
VC4_LOADSTORE_TILE_BUFFER_BUFFER_MASK |
VC4_LOADSTORE_TILE_BUFFER_FORMAT_MASK)) {
DRM_DEBUG("Unknown bits in load/store: 0x%04x\n",
surf->bits);
return -EINVAL;
}
if (tiling > VC4_TILING_FORMAT_LT) {
DRM_DEBUG("Bad tiling format\n");
return -EINVAL;
}
if (buffer == VC4_LOADSTORE_TILE_BUFFER_ZS) {
if (format != 0) {
DRM_DEBUG("No color format should be set for ZS\n");
return -EINVAL;
}
cpp = 4;
} else if (buffer == VC4_LOADSTORE_TILE_BUFFER_COLOR) {
switch (format) {
case VC4_LOADSTORE_TILE_BUFFER_BGR565:
case VC4_LOADSTORE_TILE_BUFFER_BGR565_DITHER:
cpp = 2;
break;
case VC4_LOADSTORE_TILE_BUFFER_RGBA8888:
cpp = 4;
break;
default:
DRM_DEBUG("Bad tile buffer format\n");
return -EINVAL;
}
} else {
DRM_DEBUG("Bad load/store buffer %d.\n", buffer);
return -EINVAL;
}
if (surf->offset & 0xf) {
DRM_DEBUG("load/store buffer must be 16b aligned.\n");
return -EINVAL;
}
if (!vc4_check_tex_size(exec, *obj, surf->offset, tiling,
exec->args->width, exec->args->height, cpp)) {
return -EINVAL;
}
return 0;
}
static int
vc4_rcl_render_config_surface_setup(struct vc4_exec_info *exec,
struct vc4_rcl_setup *setup,
struct drm_gem_cma_object **obj,
struct drm_vc4_submit_rcl_surface *surf)
{
uint8_t tiling = VC4_GET_FIELD(surf->bits,
VC4_RENDER_CONFIG_MEMORY_FORMAT);
uint8_t format = VC4_GET_FIELD(surf->bits,
VC4_RENDER_CONFIG_FORMAT);
int cpp;
if (surf->flags != 0) {
DRM_DEBUG("No flags supported on render config.\n");
return -EINVAL;
}
if (surf->bits & ~(VC4_RENDER_CONFIG_MEMORY_FORMAT_MASK |
VC4_RENDER_CONFIG_FORMAT_MASK |
VC4_RENDER_CONFIG_MS_MODE_4X |
VC4_RENDER_CONFIG_DECIMATE_MODE_4X)) {
DRM_DEBUG("Unknown bits in render config: 0x%04x\n",
surf->bits);
return -EINVAL;
}
if (surf->hindex == ~0)
return 0;
*obj = vc4_use_bo(exec, surf->hindex);
if (!*obj)
return -EINVAL;
exec->rcl_write_bo[exec->rcl_write_bo_count++] = *obj;
if (tiling > VC4_TILING_FORMAT_LT) {
DRM_DEBUG("Bad tiling format\n");
return -EINVAL;
}
switch (format) {
case VC4_RENDER_CONFIG_FORMAT_BGR565_DITHERED:
case VC4_RENDER_CONFIG_FORMAT_BGR565:
cpp = 2;
break;
case VC4_RENDER_CONFIG_FORMAT_RGBA8888:
cpp = 4;
break;
default:
DRM_DEBUG("Bad tile buffer format\n");
return -EINVAL;
}
if (!vc4_check_tex_size(exec, *obj, surf->offset, tiling,
exec->args->width, exec->args->height, cpp)) {
return -EINVAL;
}
return 0;
}
int vc4_get_rcl(struct drm_device *dev, struct vc4_exec_info *exec)
{
struct vc4_rcl_setup setup = {0};
struct drm_vc4_submit_cl *args = exec->args;
bool has_bin = args->bin_cl_size != 0;
int ret;
if (args->min_x_tile > args->max_x_tile ||
args->min_y_tile > args->max_y_tile) {
DRM_DEBUG("Bad render tile set (%d,%d)-(%d,%d)\n",
args->min_x_tile, args->min_y_tile,
args->max_x_tile, args->max_y_tile);
return -EINVAL;
}
if (has_bin &&
(args->max_x_tile > exec->bin_tiles_x ||
args->max_y_tile > exec->bin_tiles_y)) {
DRM_DEBUG("Render tiles (%d,%d) outside of bin config "
"(%d,%d)\n",
args->max_x_tile, args->max_y_tile,
exec->bin_tiles_x, exec->bin_tiles_y);
return -EINVAL;
}
ret = vc4_rcl_render_config_surface_setup(exec, &setup,
&setup.color_write,
&args->color_write);
if (ret)
return ret;
ret = vc4_rcl_surface_setup(exec, &setup.color_read, &args->color_read,
false);
if (ret)
return ret;
ret = vc4_rcl_surface_setup(exec, &setup.zs_read, &args->zs_read,
false);
if (ret)
return ret;
ret = vc4_rcl_surface_setup(exec, &setup.zs_write, &args->zs_write,
true);
if (ret)
return ret;
ret = vc4_rcl_msaa_surface_setup(exec, &setup.msaa_color_write,
&args->msaa_color_write);
if (ret)
return ret;
ret = vc4_rcl_msaa_surface_setup(exec, &setup.msaa_zs_write,
&args->msaa_zs_write);
if (ret)
return ret;
/* We shouldn't even have the job submitted to us if there's no
* surface to write out.
*/
if (!setup.color_write && !setup.zs_write &&
!setup.msaa_color_write && !setup.msaa_zs_write) {
DRM_DEBUG("RCL requires color or Z/S write\n");
return -EINVAL;
}
return vc4_create_rcl_bo(dev, exec, &setup);
}
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