drm/i915/gvt: Optimize MMIO register handling for some large MMIO blocks

Some of traced MMIO registers are a large continuous section. These
stuffed the MMIO lookup hash table and so waste lots of memory and
get much lower lookup performance.

Here we picked out these sections by special handling. These sections
include:
  o Display pipe registers, total 768.
  o The PVINFO page, total 1024.
  o MCHBAR_MIRROR, total 65536.
  o CSR_MMIO, total 3072.

So we removed 70,400 items from the hash table, and speed up guest
boot time by ~500ms.

v2:
  o add a local function find_mmio_block().
  o fix comments.

Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

1 files changed, 5 insertions, 81 deletions

diff --git a/drivers/gpu/drm/i915/gvt/mmio.c b/drivers/gpu/drm/i915/gvt/mmio.c
index 35f6c4713cb6..322077fce2bb 100644
--- a/drivers/gpu/drm/i915/gvt/mmio.c
+++ b/drivers/gpu/drm/i915/gvt/mmio.c
@@ -123,7 +123,6 @@ int intel_vgpu_emulate_mmio_read(struct intel_vgpu *vgpu, uint64_t pa,
 		void *p_data, unsigned int bytes)
 {
 	struct intel_gvt *gvt = vgpu->gvt;
-	struct intel_gvt_mmio_info *mmio;
 	unsigned int offset = 0;
 	int ret = -EINVAL;
 
@@ -187,25 +186,8 @@ int intel_vgpu_emulate_mmio_read(struct intel_vgpu *vgpu, uint64_t pa,
 			goto err;
 	}
 
-	mmio = intel_gvt_find_mmio_info(gvt, rounddown(offset, 4));
-	if (mmio) {
-		if (!intel_gvt_mmio_is_unalign(gvt, mmio->offset)) {
-			if (WARN_ON(offset + bytes > mmio->offset + mmio->size))
-				goto err;
-			if (WARN_ON(mmio->offset != offset))
-				goto err;
-		}
-		ret = mmio->read(vgpu, offset, p_data, bytes);
-	} else {
-		ret = intel_vgpu_default_mmio_read(vgpu, offset, p_data, bytes);
-
-		if (!vgpu->mmio.disable_warn_untrack) {
-			gvt_vgpu_err("read untracked MMIO %x(%dB) val %x\n",
-				offset, bytes, *(u32 *)p_data);
-		}
-	}
-
-	if (ret)
+	ret = intel_vgpu_mmio_reg_rw(vgpu, offset, p_data, bytes, true);
+	if (ret < 0)
 		goto err;
 
 	intel_gvt_mmio_set_accessed(gvt, offset);
@@ -232,9 +214,7 @@ int intel_vgpu_emulate_mmio_write(struct intel_vgpu *vgpu, uint64_t pa,
 		void *p_data, unsigned int bytes)
 {
 	struct intel_gvt *gvt = vgpu->gvt;
-	struct intel_gvt_mmio_info *mmio;
 	unsigned int offset = 0;
-	u32 old_vreg = 0, old_sreg = 0;
 	int ret = -EINVAL;
 
 	if (vgpu->failsafe) {
@@ -289,66 +269,10 @@ int intel_vgpu_emulate_mmio_write(struct intel_vgpu *vgpu, uint64_t pa,
 		return ret;
 	}
 
-	mmio = intel_gvt_find_mmio_info(gvt, rounddown(offset, 4));
-	if (!mmio && !vgpu->mmio.disable_warn_untrack)
-		gvt_dbg_mmio("vgpu%d: write untracked MMIO %x len %d val %x\n",
-				vgpu->id, offset, bytes, *(u32 *)p_data);
-
-	if (!intel_gvt_mmio_is_unalign(gvt, offset)) {
-		if (WARN_ON(!IS_ALIGNED(offset, bytes)))
-			goto err;
-	}
-
-	if (mmio) {
-		u64 ro_mask = mmio->ro_mask;
-
-		if (!intel_gvt_mmio_is_unalign(gvt, mmio->offset)) {
-			if (WARN_ON(offset + bytes > mmio->offset + mmio->size))
-				goto err;
-			if (WARN_ON(mmio->offset != offset))
-				goto err;
-		}
-
-		if (intel_gvt_mmio_has_mode_mask(gvt, mmio->offset)) {
-			old_vreg = vgpu_vreg(vgpu, offset);
-			old_sreg = vgpu_sreg(vgpu, offset);
-		}
-
-		if (!ro_mask) {
-			ret = mmio->write(vgpu, offset, p_data, bytes);
-		} else {
-			/* Protect RO bits like HW */
-			u64 data = 0;
-
-			/* all register bits are RO. */
-			if (ro_mask == ~(u64)0) {
-				gvt_vgpu_err("try to write RO reg %x\n",
-					offset);
-				ret = 0;
-				goto out;
-			}
-			/* keep the RO bits in the virtual register */
-			memcpy(&data, p_data, bytes);
-			data &= ~mmio->ro_mask;
-			data |= vgpu_vreg(vgpu, offset) & mmio->ro_mask;
-			ret = mmio->write(vgpu, offset, &data, bytes);
-		}
-
-		/* higher 16bits of mode ctl regs are mask bits for change */
-		if (intel_gvt_mmio_has_mode_mask(gvt, mmio->offset)) {
-			u32 mask = vgpu_vreg(vgpu, offset) >> 16;
-
-			vgpu_vreg(vgpu, offset) = (old_vreg & ~mask)
-				| (vgpu_vreg(vgpu, offset) & mask);
-			vgpu_sreg(vgpu, offset) = (old_sreg & ~mask)
-				| (vgpu_sreg(vgpu, offset) & mask);
-		}
-	} else
-		ret = intel_vgpu_default_mmio_write(vgpu, offset, p_data,
-				bytes);
-	if (ret)
+	ret = intel_vgpu_mmio_reg_rw(vgpu, offset, p_data, bytes, false);
+	if (ret < 0)
 		goto err;
-out:
+
 	intel_gvt_mmio_set_accessed(gvt, offset);
 	mutex_unlock(&gvt->lock);
 	return 0;