drivers/gpu/drm/loongson/lsdc_ttm.c
Source file repositories/reference/linux-study-clean/drivers/gpu/drm/loongson/lsdc_ttm.c
File Facts
- System
- Linux kernel
- Corpus path
drivers/gpu/drm/loongson/lsdc_ttm.c- Extension
.c- Size
- 12671 bytes
- Lines
- 590
- Domain
- Driver Families
- Bucket
- drivers/gpu
- Inferred role
- Driver Families: implementation source
- Status
- source implementation candidate
Why This File Exists
Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.
- Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.
- Uses kernel synchronization; read lock ordering, sleepability, and interrupt context assumptions before translating.
- Allocates kernel memory; connect allocation flags and lifetime to context constraints.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
drm/drm_drv.hdrm/drm_file.hdrm/drm_gem.hdrm/drm_managed.hdrm/drm_prime.hdrm/drm_print.hlsdc_drv.hlsdc_ttm.h
Detected Declarations
function Copyrightfunction lsdc_bo_set_placementfunction lsdc_ttm_tt_destroyfunction lsdc_ttm_tt_createfunction lsdc_ttm_tt_populatefunction lsdc_ttm_tt_unpopulatefunction lsdc_bo_evict_flagsfunction lsdc_bo_movefunction lsdc_bo_reserve_io_memfunction lsdc_bo_gpu_offsetfunction lsdc_bo_sizefunction lsdc_bo_reservefunction lsdc_bo_unreservefunction lsdc_bo_pinfunction lsdc_bo_unpinfunction lsdc_bo_reffunction lsdc_bo_unreffunction lsdc_bo_kmapfunction lsdc_bo_kunmapfunction lsdc_bo_clearfunction lsdc_bo_evict_vramfunction lsdc_bo_destroyfunction lsdc_bo_free_kernel_pinnedfunction lsdc_ttm_finifunction lsdc_ttm_initfunction lsdc_ttm_debugfs_init
Annotated Snippet
// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2023 Loongson Technology Corporation Limited
*/
#include <drm/drm_drv.h>
#include <drm/drm_file.h>
#include <drm/drm_gem.h>
#include <drm/drm_managed.h>
#include <drm/drm_prime.h>
#include <drm/drm_print.h>
#include "lsdc_drv.h"
#include "lsdc_ttm.h"
const char *lsdc_mem_type_to_str(uint32_t mem_type)
{
switch (mem_type) {
case TTM_PL_VRAM:
return "VRAM";
case TTM_PL_TT:
return "GTT";
case TTM_PL_SYSTEM:
return "SYSTEM";
default:
break;
}
return "Unknown";
}
const char *lsdc_domain_to_str(u32 domain)
{
switch (domain) {
case LSDC_GEM_DOMAIN_VRAM:
return "VRAM";
case LSDC_GEM_DOMAIN_GTT:
return "GTT";
case LSDC_GEM_DOMAIN_SYSTEM:
return "SYSTEM";
default:
break;
}
return "Unknown";
}
static void lsdc_bo_set_placement(struct lsdc_bo *lbo, u32 domain)
{
u32 c = 0;
u32 pflags = 0;
u32 i;
if (lbo->tbo.base.size <= PAGE_SIZE)
pflags |= TTM_PL_FLAG_TOPDOWN;
lbo->placement.placement = lbo->placements;
if (domain & LSDC_GEM_DOMAIN_VRAM) {
lbo->placements[c].mem_type = TTM_PL_VRAM;
lbo->placements[c++].flags = pflags;
}
if (domain & LSDC_GEM_DOMAIN_GTT) {
lbo->placements[c].mem_type = TTM_PL_TT;
lbo->placements[c++].flags = pflags;
}
if (domain & LSDC_GEM_DOMAIN_SYSTEM) {
lbo->placements[c].mem_type = TTM_PL_SYSTEM;
lbo->placements[c++].flags = 0;
}
if (!c) {
lbo->placements[c].mem_type = TTM_PL_SYSTEM;
lbo->placements[c++].flags = 0;
}
lbo->placement.num_placement = c;
for (i = 0; i < c; ++i) {
lbo->placements[i].fpfn = 0;
lbo->placements[i].lpfn = 0;
}
}
static void lsdc_ttm_tt_destroy(struct ttm_device *bdev, struct ttm_tt *tt)
{
ttm_tt_fini(tt);
kfree(tt);
Annotation
- Immediate include surface: `drm/drm_drv.h`, `drm/drm_file.h`, `drm/drm_gem.h`, `drm/drm_managed.h`, `drm/drm_prime.h`, `drm/drm_print.h`, `lsdc_drv.h`, `lsdc_ttm.h`.
- Detected declarations: `function Copyright`, `function lsdc_bo_set_placement`, `function lsdc_ttm_tt_destroy`, `function lsdc_ttm_tt_create`, `function lsdc_ttm_tt_populate`, `function lsdc_ttm_tt_unpopulate`, `function lsdc_bo_evict_flags`, `function lsdc_bo_move`, `function lsdc_bo_reserve_io_mem`, `function lsdc_bo_gpu_offset`.
- Atlas domain: Driver Families / drivers/gpu.
- Implementation status: source implementation candidate.
- Synchronization appears in or near this file; preserve lock ordering, sleepability, and interrupt-context constraints.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.