drm/amdgpu: Remap hdp coherency registers

Remap HDP_MEM_COHERENCY_FLUSH_CNTL and HDP_REG_COHERENCY_FLUSH_CNTL
to an empty page in mmio space. We will later map this page to process
space so application can flush hdp. This can't be done properly at
those registers' original location because it will expose more than
desired registers to process space.

v2: Use explicit register hole location
v3: Moved remapped hdp registers into adev struct
v4: Use more generic name for remapped page
    Expose register offset in kfd_ioctl.h
v5: Move hdp register remap function to nbio ip function
v6: Fixed operator precedence issue and other bugs

Signed-off-by: Oak Zeng <Oak.Zeng@amd.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
index 14398f55f602..23c3375623d7 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
@@ -639,6 +639,11 @@ struct nbio_hdp_flush_reg {
 	u32 ref_and_mask_sdma1;
 };
 
+struct amdgpu_mmio_remap {
+	u32 reg_offset;
+	resource_size_t bus_addr;
+};
+
 struct amdgpu_nbio_funcs {
 	const struct nbio_hdp_flush_reg *hdp_flush_reg;
 	u32 (*get_hdp_flush_req_offset)(struct amdgpu_device *adev);
@@ -666,6 +671,7 @@ struct amdgpu_nbio_funcs {
 	void (*ih_control)(struct amdgpu_device *adev);
 	void (*init_registers)(struct amdgpu_device *adev);
 	void (*detect_hw_virt)(struct amdgpu_device *adev);
+	void (*remap_hdp_registers)(struct amdgpu_device *adev);
 };
 
 struct amdgpu_df_funcs {
@@ -764,6 +770,7 @@ struct amdgpu_device {
 	void __iomem			*rmmio;
 	/* protects concurrent MM_INDEX/DATA based register access */
 	spinlock_t mmio_idx_lock;
+	struct amdgpu_mmio_remap        rmmio_remap;
 	/* protects concurrent SMC based register access */
 	spinlock_t smc_idx_lock;
 	amdgpu_rreg_t			smc_rreg;