drm/i915/gvt: Handle values of EDP_PSR_IMR and EDP_PSR_IIR

GVT-g only simulates DP port for guest and leaves EDP_PSR_IMR
and EDP_PSR_IIR registers as default MMIO read/write.
So guest won't get expected initial values of these registers when
initializing the gpu driver, which results in following warning and logs.

--------
Interrupt register 0x64838 is not zero: 0xffffffff
WARNING: CPU: 1 PID: 157 at drivers/gpu/drm/i915/i915_irq.c:177
gen3_assert_iir_is_zero+0x38/0xa0

Call Trace:
gen8_de_irq_postinstall+0xa7/0x400
gen8_irq_postinstall+0x27/0x80
drm_irq_install+0xbc/0x140
i915_driver_load+0xa9d/0xd50
--------
Because GVT-g does not handle EDP(embedded DP) simulation for guests,
always set EDP_PSR_IMR and EDP_PSR_IIR to value 0.

Signed-off-by: Longhe Zheng <longhe.zheng@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

drivers/gpu/drm/i915/gvt/handlers.c

@@ -1608,7 +1608,7 @@ static int bxt_gt_disp_pwron_write(struct intel_vgpu *vgpu,
 	return 0;
 }
 
-static int bxt_edp_psr_imr_iir_write(struct intel_vgpu *vgpu,
+static int edp_psr_imr_iir_write(struct intel_vgpu *vgpu,
 		unsigned int offset, void *p_data, unsigned int bytes)
 {
 	vgpu_vreg(vgpu, offset) = 0;
@@ -2613,6 +2613,9 @@ static int init_generic_mmio_info(struct intel_gvt *gvt)
 	MMIO_DFH(_MMIO(0x1a178), D_BDW_PLUS, F_CMD_ACCESS, NULL, NULL);
 	MMIO_DFH(_MMIO(0x1a17c), D_BDW_PLUS, F_CMD_ACCESS, NULL, NULL);
 	MMIO_DFH(_MMIO(0x2217c), D_BDW_PLUS, F_CMD_ACCESS, NULL, NULL);
+
+	MMIO_DH(EDP_PSR_IMR, D_BDW_PLUS, NULL, edp_psr_imr_iir_write);
+	MMIO_DH(EDP_PSR_IIR, D_BDW_PLUS, NULL, edp_psr_imr_iir_write);
 	return 0;
 }
 
@@ -3216,9 +3219,6 @@ static int init_bxt_mmio_info(struct intel_gvt *gvt)
 	MMIO_D(HSW_TVIDEO_DIP_GCP(TRANSCODER_B), D_BXT);
 	MMIO_D(HSW_TVIDEO_DIP_GCP(TRANSCODER_C), D_BXT);
 
-	MMIO_DH(EDP_PSR_IMR, D_BXT, NULL, bxt_edp_psr_imr_iir_write);
-	MMIO_DH(EDP_PSR_IIR, D_BXT, NULL, bxt_edp_psr_imr_iir_write);
-
 	MMIO_D(RC6_CTX_BASE, D_BXT);
 
 	MMIO_D(GEN8_PUSHBUS_CONTROL, D_BXT);