[PATCH v2 1/2] drm/i915/lmem: add the fake lmem region
Matthew Auld
matthew.auld at intel.com
Wed Oct 30 18:22:11 UTC 2019
Intended for upstream testing so that we can still exercise the LMEM
plumbing and !i915_ggtt_has_aperture paths. Smoke tested on Skull Canyon
device. This works by allocating an intel_memory_region for a reserved
portion of system memory, which we treat like LMEM. For the LMEMBAR we
steal the aperture and 1:1 it map to the stolen region.
To enable simply set the i915 modparam fake_lmem_start= on the kernel
cmdline with the start of reserved region(see memmap=). The size of the
region we can use is determined by the size of the mappable aperture, so
the size of reserved region should be >= mappable_end. For now we only
enable for the selftests. Depends on CONFIG_DRM_I915_UNSTABLE being
enabled.
eg. memmap=2G$16G i915.fake_lmem_start=0x400000000
v2: make fake_lmem_start an i915 modparam
Signed-off-by: Matthew Auld <matthew.auld at intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
Cc: Abdiel Janulgue <abdiel.janulgue at linux.intel.com>
Cc: Arkadiusz Hiler <arkadiusz.hiler at intel.com>
Cc: Chris Wilson <chris at chris-wilson.co.uk>
---
drivers/gpu/drm/i915/Kconfig.unstable | 8 ++
drivers/gpu/drm/i915/gem/i915_gem_lmem.c | 3 +
drivers/gpu/drm/i915/i915_drv.c | 15 ++++
drivers/gpu/drm/i915/i915_params.c | 7 ++
drivers/gpu/drm/i915/i915_params.h | 1 +
drivers/gpu/drm/i915/intel_memory_region.c | 3 +
drivers/gpu/drm/i915/intel_memory_region.h | 6 ++
drivers/gpu/drm/i915/intel_region_lmem.c | 92 ++++++++++++++++++++++
drivers/gpu/drm/i915/intel_region_lmem.h | 5 ++
9 files changed, 140 insertions(+)
diff --git a/drivers/gpu/drm/i915/Kconfig.unstable b/drivers/gpu/drm/i915/Kconfig.unstable
index cf151a297ed7..b0e5372959a1 100644
--- a/drivers/gpu/drm/i915/Kconfig.unstable
+++ b/drivers/gpu/drm/i915/Kconfig.unstable
@@ -19,3 +19,11 @@ config DRM_I915_UNSTABLE
Recommended for driver developers _only_.
If in the slightest bit of doubt, say "N".
+
+config DRM_I915_UNSTABLE_FAKE_LMEM
+ bool "Enable the experimental fake lmem"
+ depends on DRM_I915_UNSTABLE
+ default n
+ help
+ Convert some system memory into a fake local memory region for
+ testing.
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_lmem.c b/drivers/gpu/drm/i915/gem/i915_gem_lmem.c
index 926f6c940e0d..0e2bf6b7e143 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_lmem.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_lmem.c
@@ -24,6 +24,7 @@ i915_gem_object_lmem_io_map_page(struct drm_i915_gem_object *obj,
resource_size_t offset;
offset = i915_gem_object_get_dma_address(obj, n);
+ offset -= obj->mm.region->region.start;
return io_mapping_map_wc(&obj->mm.region->iomap, offset, PAGE_SIZE);
}
@@ -35,6 +36,7 @@ i915_gem_object_lmem_io_map_page_atomic(struct drm_i915_gem_object *obj,
resource_size_t offset;
offset = i915_gem_object_get_dma_address(obj, n);
+ offset -= obj->mm.region->region.start;
return io_mapping_map_atomic_wc(&obj->mm.region->iomap, offset);
}
@@ -49,6 +51,7 @@ i915_gem_object_lmem_io_map(struct drm_i915_gem_object *obj,
GEM_BUG_ON(!i915_gem_object_is_contiguous(obj));
offset = i915_gem_object_get_dma_address(obj, n);
+ offset -= obj->mm.region->region.start;
return io_mapping_map_wc(&obj->mm.region->iomap, offset, size);
}
diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index 21273b516dbe..480e2054f628 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -1483,6 +1483,21 @@ int i915_driver_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
if (!i915_modparams.nuclear_pageflip && match_info->gen < 5)
dev_priv->drm.driver_features &= ~DRIVER_ATOMIC;
+ /*
+ * Check if we support fake LMEM -- for now we only unleash this for
+ * the live selftests(test-and-exit).
+ */
+ if (IS_ENABLED(CONFIG_DRM_I915_UNSTABLE_FAKE_LMEM)) {
+ if (INTEL_GEN(dev_priv) >= 9 && i915_selftest.live < 0 &&
+ i915_modparams.fake_lmem_start) {
+ mkwrite_device_info(dev_priv)->memory_regions =
+ REGION_SMEM | REGION_LMEM | REGION_STOLEN;
+ mkwrite_device_info(dev_priv)->is_dgfx = true;
+ GEM_BUG_ON(!HAS_LMEM(dev_priv));
+ GEM_BUG_ON(!IS_DGFX(dev_priv));
+ }
+ }
+
ret = pci_enable_device(pdev);
if (ret)
goto out_fini;
diff --git a/drivers/gpu/drm/i915/i915_params.c b/drivers/gpu/drm/i915/i915_params.c
index 3fa79adb2c1c..1dd1f3652795 100644
--- a/drivers/gpu/drm/i915/i915_params.c
+++ b/drivers/gpu/drm/i915/i915_params.c
@@ -179,6 +179,11 @@ i915_param_named(enable_gvt, bool, 0400,
"Enable support for Intel GVT-g graphics virtualization host support(default:false)");
#endif
+#if IS_ENABLED(CONFIG_DRM_I915_UNSTABLE_FAKE_LMEM)
+i915_param_named_unsafe(fake_lmem_start, ulong, 0600,
+ "Fake LMEM start offset (default: 0)");
+#endif
+
static __always_inline void _print_param(struct drm_printer *p,
const char *name,
const char *type,
@@ -190,6 +195,8 @@ static __always_inline void _print_param(struct drm_printer *p,
drm_printf(p, "i915.%s=%d\n", name, *(const int *)x);
else if (!__builtin_strcmp(type, "unsigned int"))
drm_printf(p, "i915.%s=%u\n", name, *(const unsigned int *)x);
+ else if (!__builtin_strcmp(type, "unsigned long"))
+ drm_printf(p, "i915.%s=%lu\n", name, *(const unsigned long *)x);
else if (!__builtin_strcmp(type, "char *"))
drm_printf(p, "i915.%s=%s\n", name, *(const char **)x);
else
diff --git a/drivers/gpu/drm/i915/i915_params.h b/drivers/gpu/drm/i915/i915_params.h
index a276317ad74b..31b88f297fbc 100644
--- a/drivers/gpu/drm/i915/i915_params.h
+++ b/drivers/gpu/drm/i915/i915_params.h
@@ -66,6 +66,7 @@ struct drm_printer;
param(int, fastboot, -1) \
param(int, enable_dpcd_backlight, 0) \
param(char *, force_probe, CONFIG_DRM_I915_FORCE_PROBE) \
+ param(unsigned long, fake_lmem_start, 0) \
/* leave bools at the end to not create holes */ \
param(bool, alpha_support, IS_ENABLED(CONFIG_DRM_I915_ALPHA_SUPPORT)) \
param(bool, enable_hangcheck, true) \
diff --git a/drivers/gpu/drm/i915/intel_memory_region.c b/drivers/gpu/drm/i915/intel_memory_region.c
index a60f77ff58d4..baaeaecc64af 100644
--- a/drivers/gpu/drm/i915/intel_memory_region.c
+++ b/drivers/gpu/drm/i915/intel_memory_region.c
@@ -228,6 +228,9 @@ int intel_memory_regions_hw_probe(struct drm_i915_private *i915)
case INTEL_MEMORY_STOLEN:
mem = i915_gem_stolen_setup(i915);
break;
+ case INTEL_MEMORY_LOCAL:
+ mem = intel_setup_fake_lmem(i915);
+ break;
}
if (IS_ERR(mem)) {
diff --git a/drivers/gpu/drm/i915/intel_memory_region.h b/drivers/gpu/drm/i915/intel_memory_region.h
index 19920c256ede..238722009677 100644
--- a/drivers/gpu/drm/i915/intel_memory_region.h
+++ b/drivers/gpu/drm/i915/intel_memory_region.h
@@ -10,6 +10,7 @@
#include <linux/ioport.h>
#include <linux/mutex.h>
#include <linux/io-mapping.h>
+#include <drm/drm_mm.h>
#include "i915_buddy.h"
@@ -71,6 +72,9 @@ struct intel_memory_region {
struct io_mapping iomap;
struct resource region;
+ /* For fake LMEM */
+ struct drm_mm_node fake_mappable;
+
struct i915_buddy_mm mm;
struct mutex mm_lock;
@@ -83,6 +87,8 @@ struct intel_memory_region {
unsigned int instance;
unsigned int id;
+ dma_addr_t remap_addr;
+
struct {
struct mutex lock; /* Protects access to objects */
struct list_head list;
diff --git a/drivers/gpu/drm/i915/intel_region_lmem.c b/drivers/gpu/drm/i915/intel_region_lmem.c
index 9a351af45ce6..583118095635 100644
--- a/drivers/gpu/drm/i915/intel_region_lmem.c
+++ b/drivers/gpu/drm/i915/intel_region_lmem.c
@@ -9,9 +9,62 @@
#include "gem/i915_gem_region.h"
#include "intel_region_lmem.h"
+static int init_fake_lmem_bar(struct intel_memory_region *mem)
+{
+ struct drm_i915_private *i915 = mem->i915;
+ struct i915_ggtt *ggtt = &i915->ggtt;
+ unsigned long n;
+ int ret;
+
+ /* We want to 1:1 map the mappable aperture to our reserved region */
+
+ mem->fake_mappable.start = 0;
+ mem->fake_mappable.size = resource_size(&mem->region);
+ mem->fake_mappable.color = I915_COLOR_UNEVICTABLE;
+
+ ret = drm_mm_reserve_node(&ggtt->vm.mm, &mem->fake_mappable);
+ if (ret)
+ return ret;
+
+ mem->remap_addr = dma_map_resource(&i915->drm.pdev->dev,
+ mem->region.start,
+ mem->fake_mappable.size,
+ PCI_DMA_BIDIRECTIONAL,
+ DMA_ATTR_FORCE_CONTIGUOUS);
+ if (dma_mapping_error(&i915->drm.pdev->dev, mem->remap_addr)) {
+ drm_mm_remove_node(&mem->fake_mappable);
+ return -EINVAL;
+ }
+
+ for (n = 0; n < mem->fake_mappable.size >> PAGE_SHIFT; ++n) {
+ ggtt->vm.insert_page(&ggtt->vm,
+ mem->remap_addr + (n << PAGE_SHIFT),
+ n << PAGE_SHIFT,
+ I915_CACHE_NONE, 0);
+ }
+
+ mem->region = (struct resource)DEFINE_RES_MEM(mem->remap_addr,
+ mem->fake_mappable.size);
+
+ return 0;
+}
+
+static void release_fake_lmem_bar(struct intel_memory_region *mem)
+{
+ if (drm_mm_node_allocated(&mem->fake_mappable))
+ drm_mm_remove_node(&mem->fake_mappable);
+
+ dma_unmap_resource(&mem->i915->drm.pdev->dev,
+ mem->remap_addr,
+ mem->fake_mappable.size,
+ PCI_DMA_BIDIRECTIONAL,
+ DMA_ATTR_FORCE_CONTIGUOUS);
+}
+
static void
region_lmem_release(struct intel_memory_region *mem)
{
+ release_fake_lmem_bar(mem);
io_mapping_fini(&mem->iomap);
intel_memory_region_release_buddy(mem);
}
@@ -21,6 +74,11 @@ region_lmem_init(struct intel_memory_region *mem)
{
int ret;
+ if (i915_modparams.fake_lmem_start) {
+ ret = init_fake_lmem_bar(mem);
+ GEM_BUG_ON(ret);
+ }
+
if (!io_mapping_init_wc(&mem->iomap,
mem->io_start,
resource_size(&mem->region)))
@@ -38,3 +96,37 @@ const struct intel_memory_region_ops intel_region_lmem_ops = {
.release = region_lmem_release,
.create_object = __i915_gem_lmem_object_create,
};
+
+struct intel_memory_region *
+intel_setup_fake_lmem(struct drm_i915_private *i915)
+{
+ struct pci_dev *pdev = i915->drm.pdev;
+ struct intel_memory_region *mem;
+ resource_size_t mappable_end;
+ resource_size_t io_start;
+ resource_size_t start;
+
+ GEM_BUG_ON(i915_ggtt_has_aperture(&i915->ggtt));
+ GEM_BUG_ON(!i915_modparams.fake_lmem_start);
+
+ /* Your mappable aperture belongs to me now! */
+ mappable_end = pci_resource_len(pdev, 2);
+ io_start = pci_resource_start(pdev, 2),
+ start = i915_modparams.fake_lmem_start;
+
+ mem = intel_memory_region_create(i915,
+ start,
+ mappable_end,
+ PAGE_SIZE,
+ io_start,
+ &intel_region_lmem_ops);
+ if (!IS_ERR(mem)) {
+ DRM_INFO("Intel graphics fake LMEM: %pR\n", &mem->region);
+ DRM_INFO("Intel graphics fake LMEM IO start: %llx\n",
+ (u64)mem->io_start);
+ DRM_INFO("Intel graphics fake LMEM size: %llx\n",
+ (u64)resource_size(&mem->region));
+ }
+
+ return mem;
+}
diff --git a/drivers/gpu/drm/i915/intel_region_lmem.h b/drivers/gpu/drm/i915/intel_region_lmem.h
index ed2a3bab6443..213def7c7b8a 100644
--- a/drivers/gpu/drm/i915/intel_region_lmem.h
+++ b/drivers/gpu/drm/i915/intel_region_lmem.h
@@ -6,6 +6,11 @@
#ifndef __INTEL_REGION_LMEM_H
#define __INTEL_REGION_LMEM_H
+struct drm_i915_private;
+
extern const struct intel_memory_region_ops intel_region_lmem_ops;
+struct intel_memory_region *
+intel_setup_fake_lmem(struct drm_i915_private *i915);
+
#endif /* !__INTEL_REGION_LMEM_H */
--
2.20.1
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