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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/drivers/gpu/drm/i915/i915_vgpu.c
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/drivers/gpu/drm/i915/i915_vgpu.c')
-rw-r--r--kernel/drivers/gpu/drm/i915/i915_vgpu.c264
1 files changed, 264 insertions, 0 deletions
diff --git a/kernel/drivers/gpu/drm/i915/i915_vgpu.c b/kernel/drivers/gpu/drm/i915/i915_vgpu.c
new file mode 100644
index 000000000..5eee75bff
--- /dev/null
+++ b/kernel/drivers/gpu/drm/i915/i915_vgpu.c
@@ -0,0 +1,264 @@
+/*
+ * Copyright(c) 2011-2015 Intel Corporation. All rights reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include "intel_drv.h"
+#include "i915_vgpu.h"
+
+/**
+ * DOC: Intel GVT-g guest support
+ *
+ * Intel GVT-g is a graphics virtualization technology which shares the
+ * GPU among multiple virtual machines on a time-sharing basis. Each
+ * virtual machine is presented a virtual GPU (vGPU), which has equivalent
+ * features as the underlying physical GPU (pGPU), so i915 driver can run
+ * seamlessly in a virtual machine. This file provides vGPU specific
+ * optimizations when running in a virtual machine, to reduce the complexity
+ * of vGPU emulation and to improve the overall performance.
+ *
+ * A primary function introduced here is so-called "address space ballooning"
+ * technique. Intel GVT-g partitions global graphics memory among multiple VMs,
+ * so each VM can directly access a portion of the memory without hypervisor's
+ * intervention, e.g. filling textures or queuing commands. However with the
+ * partitioning an unmodified i915 driver would assume a smaller graphics
+ * memory starting from address ZERO, then requires vGPU emulation module to
+ * translate the graphics address between 'guest view' and 'host view', for
+ * all registers and command opcodes which contain a graphics memory address.
+ * To reduce the complexity, Intel GVT-g introduces "address space ballooning",
+ * by telling the exact partitioning knowledge to each guest i915 driver, which
+ * then reserves and prevents non-allocated portions from allocation. Thus vGPU
+ * emulation module only needs to scan and validate graphics addresses without
+ * complexity of address translation.
+ *
+ */
+
+/**
+ * i915_check_vgpu - detect virtual GPU
+ * @dev: drm device *
+ *
+ * This function is called at the initialization stage, to detect whether
+ * running on a vGPU.
+ */
+void i915_check_vgpu(struct drm_device *dev)
+{
+ struct drm_i915_private *dev_priv = to_i915(dev);
+ uint64_t magic;
+ uint32_t version;
+
+ BUILD_BUG_ON(sizeof(struct vgt_if) != VGT_PVINFO_SIZE);
+
+ if (!IS_HASWELL(dev))
+ return;
+
+ magic = readq(dev_priv->regs + vgtif_reg(magic));
+ if (magic != VGT_MAGIC)
+ return;
+
+ version = INTEL_VGT_IF_VERSION_ENCODE(
+ readw(dev_priv->regs + vgtif_reg(version_major)),
+ readw(dev_priv->regs + vgtif_reg(version_minor)));
+ if (version != INTEL_VGT_IF_VERSION) {
+ DRM_INFO("VGT interface version mismatch!\n");
+ return;
+ }
+
+ dev_priv->vgpu.active = true;
+ DRM_INFO("Virtual GPU for Intel GVT-g detected.\n");
+}
+
+struct _balloon_info_ {
+ /*
+ * There are up to 2 regions per mappable/unmappable graphic
+ * memory that might be ballooned. Here, index 0/1 is for mappable
+ * graphic memory, 2/3 for unmappable graphic memory.
+ */
+ struct drm_mm_node space[4];
+};
+
+static struct _balloon_info_ bl_info;
+
+/**
+ * intel_vgt_deballoon - deballoon reserved graphics address trunks
+ *
+ * This function is called to deallocate the ballooned-out graphic memory, when
+ * driver is unloaded or when ballooning fails.
+ */
+void intel_vgt_deballoon(void)
+{
+ int i;
+
+ DRM_DEBUG("VGT deballoon.\n");
+
+ for (i = 0; i < 4; i++) {
+ if (bl_info.space[i].allocated)
+ drm_mm_remove_node(&bl_info.space[i]);
+ }
+
+ memset(&bl_info, 0, sizeof(bl_info));
+}
+
+static int vgt_balloon_space(struct drm_mm *mm,
+ struct drm_mm_node *node,
+ unsigned long start, unsigned long end)
+{
+ unsigned long size = end - start;
+
+ if (start == end)
+ return -EINVAL;
+
+ DRM_INFO("balloon space: range [ 0x%lx - 0x%lx ] %lu KiB.\n",
+ start, end, size / 1024);
+
+ node->start = start;
+ node->size = size;
+
+ return drm_mm_reserve_node(mm, node);
+}
+
+/**
+ * intel_vgt_balloon - balloon out reserved graphics address trunks
+ * @dev: drm device
+ *
+ * This function is called at the initialization stage, to balloon out the
+ * graphic address space allocated to other vGPUs, by marking these spaces as
+ * reserved. The ballooning related knowledge(starting address and size of
+ * the mappable/unmappable graphic memory) is described in the vgt_if structure
+ * in a reserved mmio range.
+ *
+ * To give an example, the drawing below depicts one typical scenario after
+ * ballooning. Here the vGPU1 has 2 pieces of graphic address spaces ballooned
+ * out each for the mappable and the non-mappable part. From the vGPU1 point of
+ * view, the total size is the same as the physical one, with the start address
+ * of its graphic space being zero. Yet there are some portions ballooned out(
+ * the shadow part, which are marked as reserved by drm allocator). From the
+ * host point of view, the graphic address space is partitioned by multiple
+ * vGPUs in different VMs.
+ *
+ * vGPU1 view Host view
+ * 0 ------> +-----------+ +-----------+
+ * ^ |///////////| | vGPU3 |
+ * | |///////////| +-----------+
+ * | |///////////| | vGPU2 |
+ * | +-----------+ +-----------+
+ * mappable GM | available | ==> | vGPU1 |
+ * | +-----------+ +-----------+
+ * | |///////////| | |
+ * v |///////////| | Host |
+ * +=======+===========+ +===========+
+ * ^ |///////////| | vGPU3 |
+ * | |///////////| +-----------+
+ * | |///////////| | vGPU2 |
+ * | +-----------+ +-----------+
+ * unmappable GM | available | ==> | vGPU1 |
+ * | +-----------+ +-----------+
+ * | |///////////| | |
+ * | |///////////| | Host |
+ * v |///////////| | |
+ * total GM size ------> +-----------+ +-----------+
+ *
+ * Returns:
+ * zero on success, non-zero if configuration invalid or ballooning failed
+ */
+int intel_vgt_balloon(struct drm_device *dev)
+{
+ struct drm_i915_private *dev_priv = to_i915(dev);
+ struct i915_address_space *ggtt_vm = &dev_priv->gtt.base;
+ unsigned long ggtt_vm_end = ggtt_vm->start + ggtt_vm->total;
+
+ unsigned long mappable_base, mappable_size, mappable_end;
+ unsigned long unmappable_base, unmappable_size, unmappable_end;
+ int ret;
+
+ mappable_base = I915_READ(vgtif_reg(avail_rs.mappable_gmadr.base));
+ mappable_size = I915_READ(vgtif_reg(avail_rs.mappable_gmadr.size));
+ unmappable_base = I915_READ(vgtif_reg(avail_rs.nonmappable_gmadr.base));
+ unmappable_size = I915_READ(vgtif_reg(avail_rs.nonmappable_gmadr.size));
+
+ mappable_end = mappable_base + mappable_size;
+ unmappable_end = unmappable_base + unmappable_size;
+
+ DRM_INFO("VGT ballooning configuration:\n");
+ DRM_INFO("Mappable graphic memory: base 0x%lx size %ldKiB\n",
+ mappable_base, mappable_size / 1024);
+ DRM_INFO("Unmappable graphic memory: base 0x%lx size %ldKiB\n",
+ unmappable_base, unmappable_size / 1024);
+
+ if (mappable_base < ggtt_vm->start ||
+ mappable_end > dev_priv->gtt.mappable_end ||
+ unmappable_base < dev_priv->gtt.mappable_end ||
+ unmappable_end > ggtt_vm_end) {
+ DRM_ERROR("Invalid ballooning configuration!\n");
+ return -EINVAL;
+ }
+
+ /* Unmappable graphic memory ballooning */
+ if (unmappable_base > dev_priv->gtt.mappable_end) {
+ ret = vgt_balloon_space(&ggtt_vm->mm,
+ &bl_info.space[2],
+ dev_priv->gtt.mappable_end,
+ unmappable_base);
+
+ if (ret)
+ goto err;
+ }
+
+ /*
+ * No need to partition out the last physical page,
+ * because it is reserved to the guard page.
+ */
+ if (unmappable_end < ggtt_vm_end - PAGE_SIZE) {
+ ret = vgt_balloon_space(&ggtt_vm->mm,
+ &bl_info.space[3],
+ unmappable_end,
+ ggtt_vm_end - PAGE_SIZE);
+ if (ret)
+ goto err;
+ }
+
+ /* Mappable graphic memory ballooning */
+ if (mappable_base > ggtt_vm->start) {
+ ret = vgt_balloon_space(&ggtt_vm->mm,
+ &bl_info.space[0],
+ ggtt_vm->start, mappable_base);
+
+ if (ret)
+ goto err;
+ }
+
+ if (mappable_end < dev_priv->gtt.mappable_end) {
+ ret = vgt_balloon_space(&ggtt_vm->mm,
+ &bl_info.space[1],
+ mappable_end,
+ dev_priv->gtt.mappable_end);
+
+ if (ret)
+ goto err;
+ }
+
+ DRM_INFO("VGT balloon successfully\n");
+ return 0;
+
+err:
+ DRM_ERROR("VGT balloon fail\n");
+ intel_vgt_deballoon();
+ return ret;
+}