/*
* Copyright (c) 2017, NVIDIA CORPORATION. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef __NVGPU_COMPTAGS__
#define __NVGPU_COMPTAGS__
#include <nvgpu/lock.h>
struct gk20a;
struct nvgpu_os_buffer;
struct gk20a_comptags {
u32 offset;
u32 lines;
/*
* This signals whether allocation has been attempted. Observe 'lines'
* to see whether the comptags were actually allocated. We try alloc
* only once per buffer in order not to break multiple compressible-kind
* mappings.
*/
bool allocated;
/*
* Do comptags need to be cleared before mapping?
*/
bool needs_clear;
};
struct gk20a_comptag_allocator {
struct gk20a *g;
struct nvgpu_mutex lock;
/* This bitmap starts at ctag 1. 0th cannot be taken. */
unsigned long *bitmap;
/* Size of bitmap, not max ctags, so one less. */
unsigned long size;
};
/* real size here, but first (ctag 0) isn't used */
int gk20a_comptag_allocator_init(struct gk20a *g,
struct gk20a_comptag_allocator *allocator,
unsigned long size);
void gk20a_comptag_allocator_destroy(struct gk20a *g,
struct gk20a_comptag_allocator *allocator);
int gk20a_comptaglines_alloc(struct gk20a_comptag_allocator *allocator,
u32 *offset, u32 len);
void gk20a_comptaglines_free(struct gk20a_comptag_allocator *allocator,
u32 offset, u32 len);
/*
* Defined by OS specific code since comptags are stored in a highly OS specific
* way.
*/
int gk20a_alloc_or_get_comptags(struct gk20a *g,
struct nvgpu_os_buffer *buf,
struct gk20a_comptag_allocator *allocator,
struct gk20a_comptags *comptags);
void gk20a_get_comptags(struct nvgpu_os_buffer *buf,
struct gk20a_comptags *comptags);
/*
* These functions must be used to synchronize comptags clear. The usage:
*
* if (gk20a_comptags_start_clear(os_buf)) {
* // we now hold the buffer lock for clearing
*
* bool successful = hw_clear_comptags();
*
* // mark the buf cleared (or not) and release the buffer lock
* gk20a_comptags_finish_clear(os_buf, successful);
* }
*
* If gk20a_start_comptags_clear() returns false, another caller has
* already cleared the comptags.
*/
bool gk20a_comptags_start_clear(struct nvgpu_os_buffer *buf);
void gk20a_comptags_finish_clear(struct nvgpu_os_buffer *buf,
bool clear_successful);
#endif