Re: [PATCH 2/9] Revert "drm/msm/a6xx: Use the DMA API for GMU memory objects"
From: Jonathan Marek
Date: Mon Apr 20 2020 - 15:59:39 EST
On 4/20/20 3:51 PM, Bjorn Andersson wrote:
On Mon 20 Apr 07:03 PDT 2020, Jonathan Marek wrote:
This reverts commit a5fb8b918920c6f7706a8b5b8ea535a7f077a7f6.
Why?
It removes something I need for the next patches in the series, however
I'm open to suggestions on a better solution (Jordan said he would check
it out)
---
drivers/gpu/drm/msm/adreno/a6xx_gmu.c | 115 +++++++++++++++++++++++---
drivers/gpu/drm/msm/adreno/a6xx_gmu.h | 6 +-
2 files changed, 107 insertions(+), 14 deletions(-)
diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gmu.c b/drivers/gpu/drm/msm/adreno/a6xx_gmu.c
index c4e71abbdd53..748cd379065f 100644
--- a/drivers/gpu/drm/msm/adreno/a6xx_gmu.c
+++ b/drivers/gpu/drm/msm/adreno/a6xx_gmu.c
@@ -2,7 +2,6 @@
/* Copyright (c) 2017-2019 The Linux Foundation. All rights reserved. */
#include <linux/clk.h>
-#include <linux/dma-mapping.h>
#include <linux/interconnect.h>
#include <linux/pm_domain.h>
#include <linux/pm_opp.h>
@@ -921,10 +920,21 @@ int a6xx_gmu_stop(struct a6xx_gpu *a6xx_gpu)
static void a6xx_gmu_memory_free(struct a6xx_gmu *gmu, struct a6xx_gmu_bo *bo)
{
+ int count, i;
+ u64 iova;
+
if (IS_ERR_OR_NULL(bo))
return;
- dma_free_wc(gmu->dev, bo->size, bo->virt, bo->iova);
+ count = bo->size >> PAGE_SHIFT;
+ iova = bo->iova;
+
+ for (i = 0; i < count; i++, iova += PAGE_SIZE) {
+ iommu_unmap(gmu->domain, iova, PAGE_SIZE);
+ __free_pages(bo->pages[i], 0);
+ }
+
+ kfree(bo->pages);
kfree(bo);
}
@@ -932,6 +942,7 @@ static struct a6xx_gmu_bo *a6xx_gmu_memory_alloc(struct a6xx_gmu *gmu,
size_t size)
{
struct a6xx_gmu_bo *bo;
+ int ret, count, i;
bo = kzalloc(sizeof(*bo), GFP_KERNEL);
if (!bo)
@@ -939,14 +950,86 @@ static struct a6xx_gmu_bo *a6xx_gmu_memory_alloc(struct a6xx_gmu *gmu,
bo->size = PAGE_ALIGN(size);
- bo->virt = dma_alloc_wc(gmu->dev, bo->size, &bo->iova, GFP_KERNEL);
+ count = bo->size >> PAGE_SHIFT;
- if (!bo->virt) {
+ bo->pages = kcalloc(count, sizeof(struct page *), GFP_KERNEL);
+ if (!bo->pages) {
kfree(bo);
return ERR_PTR(-ENOMEM);
}
+ for (i = 0; i < count; i++) {
+ bo->pages[i] = alloc_page(GFP_KERNEL);
+ if (!bo->pages[i])
+ goto err;
+ }
+
+ bo->iova = gmu->uncached_iova_base;
+
+ for (i = 0; i < count; i++) {
+ ret = iommu_map(gmu->domain,
+ bo->iova + (PAGE_SIZE * i),
+ page_to_phys(bo->pages[i]), PAGE_SIZE,
+ IOMMU_READ | IOMMU_WRITE);
+
+ if (ret) {
+ DRM_DEV_ERROR(gmu->dev, "Unable to map GMU buffer object\n");
+
+ for (i = i - 1 ; i >= 0; i--)
+ iommu_unmap(gmu->domain,
+ bo->iova + (PAGE_SIZE * i),
+ PAGE_SIZE);
+
+ goto err;
+ }
+ }
+
+ bo->virt = vmap(bo->pages, count, VM_IOREMAP,
+ pgprot_writecombine(PAGE_KERNEL));
+ if (!bo->virt)
+ goto err;
+
+ /* Align future IOVA addresses on 1MB boundaries */
+ gmu->uncached_iova_base += ALIGN(size, SZ_1M);
+
return bo;
+
+err:
+ for (i = 0; i < count; i++) {
+ if (bo->pages[i])
+ __free_pages(bo->pages[i], 0);
+ }
+
+ kfree(bo->pages);
+ kfree(bo);
+
+ return ERR_PTR(-ENOMEM);
+}
+
+static int a6xx_gmu_memory_probe(struct a6xx_gmu *gmu)
+{
+ int ret;
+
+ /*
+ * The GMU address space is hardcoded to treat the range
+ * 0x60000000 - 0x80000000 as un-cached memory. All buffers shared
+ * between the GMU and the CPU will live in this space
+ */
+ gmu->uncached_iova_base = 0x60000000;
+
+
+ gmu->domain = iommu_domain_alloc(&platform_bus_type);
+ if (!gmu->domain)
+ return -ENODEV;
+
+ ret = iommu_attach_device(gmu->domain, gmu->dev);
+
+ if (ret) {
+ iommu_domain_free(gmu->domain);
+ gmu->domain = NULL;
+ }
+
+ return ret;
}
/* Return the 'arc-level' for the given frequency */
@@ -1206,6 +1289,10 @@ void a6xx_gmu_remove(struct a6xx_gpu *a6xx_gpu)
a6xx_gmu_memory_free(gmu, gmu->hfi);
+ iommu_detach_device(gmu->domain, gmu->dev);
+
+ iommu_domain_free(gmu->domain);
+
free_irq(gmu->gmu_irq, gmu);
free_irq(gmu->hfi_irq, gmu);
@@ -1226,15 +1313,7 @@ int a6xx_gmu_init(struct a6xx_gpu *a6xx_gpu, struct device_node *node)
gmu->dev = &pdev->dev;
- /* Pass force_dma false to require the DT to set the dma region */
- ret = of_dma_configure(gmu->dev, node, false);
- if (ret)
- return ret;
-
- /* Set the mask after the of_dma_configure() */
- ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(31));
- if (ret)
- return ret;
+ of_dma_configure(gmu->dev, node, true);
/* Fow now, don't do anything fancy until we get our feet under us */
gmu->idle_level = GMU_IDLE_STATE_ACTIVE;
@@ -1246,6 +1325,11 @@ int a6xx_gmu_init(struct a6xx_gpu *a6xx_gpu, struct device_node *node)
if (ret)
goto err_put_device;
+ /* Set up the IOMMU context bank */
+ ret = a6xx_gmu_memory_probe(gmu);
+ if (ret)
+ goto err_put_device;
+
/* Allocate memory for for the HFI queues */
gmu->hfi = a6xx_gmu_memory_alloc(gmu, SZ_16K);
if (IS_ERR(gmu->hfi))
@@ -1291,6 +1375,11 @@ int a6xx_gmu_init(struct a6xx_gpu *a6xx_gpu, struct device_node *node)
err_memory:
a6xx_gmu_memory_free(gmu, gmu->hfi);
+ if (gmu->domain) {
+ iommu_detach_device(gmu->domain, gmu->dev);
+
+ iommu_domain_free(gmu->domain);
+ }
ret = -ENODEV;
err_put_device:
diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gmu.h b/drivers/gpu/drm/msm/adreno/a6xx_gmu.h
index 4af65a36d5ca..2af91ed7ed0c 100644
--- a/drivers/gpu/drm/msm/adreno/a6xx_gmu.h
+++ b/drivers/gpu/drm/msm/adreno/a6xx_gmu.h
@@ -12,7 +12,8 @@
struct a6xx_gmu_bo {
void *virt;
size_t size;
- dma_addr_t iova;
+ u64 iova;
+ struct page **pages;
};
/*
@@ -48,6 +49,9 @@ struct a6xx_gmu {
int hfi_irq;
int gmu_irq;
+ struct iommu_domain *domain;
+ u64 uncached_iova_base;
+
struct device *gxpd;
int idle_level;
--
2.26.1