[PATCH 2/6] drm/amdgpu: add dce_v6_0_soft_reset() to DCE6

[Alexandre Demers <alexandre.f.demers@gmail.com>]

DCE6 was missing soft reset, but it was easily identifiable under radeon.
This should be it, pretty much as it is done under DCE8 and DCE10.

Signed-off-by: Alexandre Demers <alexandre.f.demers@gmail.com>
---
 drivers/gpu/drm/amd/amdgpu/dce_v6_0.c | 62 ++++++++++++++++++++++++---
 1 file changed, 57 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/dce_v6_0.c b/drivers/gpu/drm/amd/amdgpu/dce_v6_0.c
index bd763fde1c50..254cb73324c6 100644
--- a/drivers/gpu/drm/amd/amdgpu/dce_v6_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/dce_v6_0.c
@@ -371,27 +371,58 @@ static u32 dce_v6_0_hpd_get_gpio_reg(struct amdgpu_device *adev)
 	return mmDC_GPIO_HPD_A;
 }
 
+static bool dce_v6_0_is_display_hung(struct amdgpu_device *adev)
+{
+	u32 crtc_hung = 0;
+	u32 crtc_status[6];
+	u32 i, j, tmp;
+
+	for (i = 0; i < adev->mode_info.num_crtc; i++) {
+		if (RREG32(mmCRTC_CONTROL + crtc_offsets[i]) & CRTC_CONTROL__CRTC_MASTER_EN_MASK) {
+			crtc_status[i] = RREG32(mmCRTC_STATUS_HV_COUNT + crtc_offsets[i]);
+			crtc_hung |= (1 << i);
+		}
+	}
+
+	for (j = 0; j < 10; j++) {
+		for (i = 0; i < adev->mode_info.num_crtc; i++) {
+			if (crtc_hung & (1 << i)) {
+				tmp = RREG32(mmCRTC_STATUS_HV_COUNT + crtc_offsets[i]);
+				if (tmp != crtc_status[i])
+					crtc_hung &= ~(1 << i);
+			}
+		}
+		if (crtc_hung == 0)
+			return false;
+		udelay(100);
+	}
+
+	return true;
+}
+
 static void dce_v6_0_set_vga_render_state(struct amdgpu_device *adev,
 					  bool render)
 {
 	if (!render)
 		WREG32(mmVGA_RENDER_CONTROL,
 			RREG32(mmVGA_RENDER_CONTROL) & VGA_VSTATUS_CNTL);
-
 }
 
 static int dce_v6_0_get_num_crtc(struct amdgpu_device *adev)
 {
+	int num_crtc = 0;
+
 	switch (adev->asic_type) {
 	case CHIP_TAHITI:
 	case CHIP_PITCAIRN:
 	case CHIP_VERDE:
-		return 6;
+		num_crtc = 6;
 	case CHIP_OLAND:
-		return 2;
+		num_crtc = 2;
 	default:
-		return 0;
+		num_crtc = 0;
 	}
+	return num_crtc;
 }
 
 void dce_v6_0_disable_dce(struct amdgpu_device *adev)
@@ -2846,7 +2877,28 @@ static bool dce_v6_0_is_idle(void *handle)
 
 static int dce_v6_0_soft_reset(struct amdgpu_ip_block *ip_block)
 {
-	DRM_INFO("xxxx: dce_v6_0_soft_reset --- no impl!!\n");
+	u32 srbm_soft_reset = 0, tmp;
+	struct amdgpu_device *adev = ip_block->adev;
+
+	if (dce_v6_0_is_display_hung(adev))
+		srbm_soft_reset |= SRBM_SOFT_RESET__SOFT_RESET_DC_MASK;
+
+	if (srbm_soft_reset) {
+		tmp = RREG32(mmSRBM_SOFT_RESET);
+		tmp |= srbm_soft_reset;
+		dev_info(adev->dev, "SRBM_SOFT_RESET=0x%08X\n", tmp);
+		WREG32(mmSRBM_SOFT_RESET, tmp);
+		tmp = RREG32(mmSRBM_SOFT_RESET);
+
+		udelay(50);
+
+		tmp &= ~srbm_soft_reset;
+		WREG32(mmSRBM_SOFT_RESET, tmp);
+		tmp = RREG32(mmSRBM_SOFT_RESET);
+
+		/* Wait a little for things to settle down */
+		udelay(50);
+	}
 	return 0;
 }
 
-- 
2.48.1