OpenCloudOS-Kernel/drivers/gpu/drm/v3d/v3d_mmu.c

124 lines
3.4 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/* Copyright (C) 2017-2018 Broadcom */
/**
* DOC: Broadcom V3D MMU
*
* The V3D 3.x hardware (compared to VC4) now includes an MMU. It has
* a single level of page tables for the V3D's 4GB address space to
* map to AXI bus addresses, thus it could need up to 4MB of
* physically contiguous memory to store the PTEs.
*
* Because the 4MB of contiguous memory for page tables is precious,
* and switching between them is expensive, we load all BOs into the
* same 4GB address space.
*
* To protect clients from each other, we should use the GMP to
* quickly mask out (at 128kb granularity) what pages are available to
* each client. This is not yet implemented.
*/
#include "v3d_drv.h"
#include "v3d_regs.h"
#define V3D_MMU_PAGE_SHIFT 12
/* Note: All PTEs for the 1MB superpage must be filled with the
* superpage bit set.
*/
#define V3D_PTE_SUPERPAGE BIT(31)
#define V3D_PTE_WRITEABLE BIT(29)
#define V3D_PTE_VALID BIT(28)
static int v3d_mmu_flush_all(struct v3d_dev *v3d)
{
int ret;
/* Make sure that another flush isn't already running when we
* start this one.
*/
ret = wait_for(!(V3D_READ(V3D_MMU_CTL) &
V3D_MMU_CTL_TLB_CLEARING), 100);
if (ret)
dev_err(v3d->dev, "TLB clear wait idle pre-wait failed\n");
V3D_WRITE(V3D_MMU_CTL, V3D_READ(V3D_MMU_CTL) |
V3D_MMU_CTL_TLB_CLEAR);
V3D_WRITE(V3D_MMUC_CONTROL,
V3D_MMUC_CONTROL_FLUSH |
V3D_MMUC_CONTROL_ENABLE);
ret = wait_for(!(V3D_READ(V3D_MMU_CTL) &
V3D_MMU_CTL_TLB_CLEARING), 100);
if (ret) {
dev_err(v3d->dev, "TLB clear wait idle failed\n");
return ret;
}
ret = wait_for(!(V3D_READ(V3D_MMUC_CONTROL) &
V3D_MMUC_CONTROL_FLUSHING), 100);
if (ret)
dev_err(v3d->dev, "MMUC flush wait idle failed\n");
return ret;
}
int v3d_mmu_set_page_table(struct v3d_dev *v3d)
{
V3D_WRITE(V3D_MMU_PT_PA_BASE, v3d->pt_paddr >> V3D_MMU_PAGE_SHIFT);
V3D_WRITE(V3D_MMU_CTL,
V3D_MMU_CTL_ENABLE |
V3D_MMU_CTL_PT_INVALID |
V3D_MMU_CTL_PT_INVALID_ABORT |
V3D_MMU_CTL_WRITE_VIOLATION_ABORT |
V3D_MMU_CTL_CAP_EXCEEDED_ABORT);
V3D_WRITE(V3D_MMU_ILLEGAL_ADDR,
(v3d->mmu_scratch_paddr >> V3D_MMU_PAGE_SHIFT) |
V3D_MMU_ILLEGAL_ADDR_ENABLE);
V3D_WRITE(V3D_MMUC_CONTROL, V3D_MMUC_CONTROL_ENABLE);
return v3d_mmu_flush_all(v3d);
}
void v3d_mmu_insert_ptes(struct v3d_bo *bo)
{
struct drm_gem_shmem_object *shmem_obj = &bo->base;
struct v3d_dev *v3d = to_v3d_dev(shmem_obj->base.dev);
u32 page = bo->node.start;
u32 page_prot = V3D_PTE_WRITEABLE | V3D_PTE_VALID;
unsigned int count;
struct scatterlist *sgl;
for_each_sg(shmem_obj->sgt->sgl, sgl, shmem_obj->sgt->nents, count) {
u32 page_address = sg_dma_address(sgl) >> V3D_MMU_PAGE_SHIFT;
u32 pte = page_prot | page_address;
u32 i;
BUG_ON(page_address + (sg_dma_len(sgl) >> V3D_MMU_PAGE_SHIFT) >=
BIT(24));
for (i = 0; i < sg_dma_len(sgl) >> V3D_MMU_PAGE_SHIFT; i++)
v3d->pt[page++] = pte + i;
}
WARN_ON_ONCE(page - bo->node.start !=
shmem_obj->base.size >> V3D_MMU_PAGE_SHIFT);
if (v3d_mmu_flush_all(v3d))
dev_err(v3d->dev, "MMU flush timeout\n");
}
void v3d_mmu_remove_ptes(struct v3d_bo *bo)
{
struct v3d_dev *v3d = to_v3d_dev(bo->base.base.dev);
u32 npages = bo->base.base.size >> V3D_MMU_PAGE_SHIFT;
u32 page;
for (page = bo->node.start; page < bo->node.start + npages; page++)
v3d->pt[page] = 0;
if (v3d_mmu_flush_all(v3d))
dev_err(v3d->dev, "MMU flush timeout\n");
}