[PATCH] drm/radeon: add a way to query the number of render backends on SI and CIK

[Marek Olšák]

From: Marek Olšák <marek.olsak at amd.com>

Needed by userspace for HTILE buffer size calculations.

Signed-off-by: Marek Olšák <marek.olsak at amd.com>
---

It returns 2 on Bonaire. I hope it's correct.

 drivers/gpu/drm/radeon/cik.c        | 7 ++++++-
 drivers/gpu/drm/radeon/radeon_kms.c | 9 +++++++++
 drivers/gpu/drm/radeon/si.c         | 7 ++++++-
 include/uapi/drm/radeon_drm.h       | 2 ++
 4 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/radeon/cik.c b/drivers/gpu/drm/radeon/cik.c
index b43a3a3..ccbbeb1 100644
--- a/drivers/gpu/drm/radeon/cik.c
+++ b/drivers/gpu/drm/radeon/cik.c
@@ -3094,6 +3094,7 @@ static void cik_setup_rb(struct radeon_device *rdev,
 	u32 data, mask;
 	u32 disabled_rbs = 0;
 	u32 enabled_rbs = 0;
+	u32 num_enabled_rbs = 0;
 
 	for (i = 0; i < se_num; i++) {
 		for (j = 0; j < sh_per_se; j++) {
@@ -3109,8 +3110,10 @@ static void cik_setup_rb(struct radeon_device *rdev,
 
 	mask = 1;
 	for (i = 0; i < max_rb_num; i++) {
-		if (!(disabled_rbs & mask))
+		if (!(disabled_rbs & mask)) {
 			enabled_rbs |= mask;
+			num_enabled_rbs++;
+		}
 		mask <<= 1;
 	}
 
@@ -3141,6 +3144,8 @@ static void cik_setup_rb(struct radeon_device *rdev,
 		WREG32(PA_SC_RASTER_CONFIG, data);
 	}
 	cik_select_se_sh(rdev, 0xffffffff, 0xffffffff);
+
+	rdev->config.cik.num_backends_per_se = num_enabled_rbs;
 }
 
 /**
diff --git a/drivers/gpu/drm/radeon/radeon_kms.c b/drivers/gpu/drm/radeon/radeon_kms.c
index 55d0b47..39d22de 100644
--- a/drivers/gpu/drm/radeon/radeon_kms.c
+++ b/drivers/gpu/drm/radeon/radeon_kms.c
@@ -461,6 +461,15 @@ int radeon_info_ioctl(struct drm_device *dev, void *data, struct drm_file *filp)
 	case RADEON_INFO_SI_CP_DMA_COMPUTE:
 		*value = 1;
 		break;
+	case RADEON_INFO_SI_NUM_RENDER_BACKENDS:
+		if (rdev->family >= CHIP_BONAIRE) {
+			*value = rdev->config.cik.num_backends_per_se;
+		} else if (rdev->family >= CHIP_TAHITI) {
+			*value = rdev->config.si.num_backends_per_se;
+		} else {
+			DRM_DEBUG_KMS("INFO_SI_NUM_RENDER_BACKENDS is si+ only!\n");
+		}
+		break;
 	default:
 		DRM_DEBUG_KMS("Invalid request %d\n", info->request);
 		return -EINVAL;
diff --git a/drivers/gpu/drm/radeon/si.c b/drivers/gpu/drm/radeon/si.c
index a36736d..0e730d6 100644
--- a/drivers/gpu/drm/radeon/si.c
+++ b/drivers/gpu/drm/radeon/si.c
@@ -2838,6 +2838,7 @@ static void si_setup_rb(struct radeon_device *rdev,
 	u32 data, mask;
 	u32 disabled_rbs = 0;
 	u32 enabled_rbs = 0;
+	u32 num_enabled_rbs = 0;
 
 	for (i = 0; i < se_num; i++) {
 		for (j = 0; j < sh_per_se; j++) {
@@ -2850,8 +2851,10 @@ static void si_setup_rb(struct radeon_device *rdev,
 
 	mask = 1;
 	for (i = 0; i < max_rb_num; i++) {
-		if (!(disabled_rbs & mask))
+		if (!(disabled_rbs & mask)) {
 			enabled_rbs |= mask;
+			num_enabled_rbs++;
+		}
 		mask <<= 1;
 	}
 
@@ -2876,6 +2879,8 @@ static void si_setup_rb(struct radeon_device *rdev,
 		WREG32(PA_SC_RASTER_CONFIG, data);
 	}
 	si_select_se_sh(rdev, 0xffffffff, 0xffffffff);
+
+	rdev->config.si.num_backends_per_se = num_enabled_rbs;
 }
 
 static void si_gpu_init(struct radeon_device *rdev)
diff --git a/include/uapi/drm/radeon_drm.h b/include/uapi/drm/radeon_drm.h
index 2f3f7ea..a64713a 100644
--- a/include/uapi/drm/radeon_drm.h
+++ b/include/uapi/drm/radeon_drm.h
@@ -983,6 +983,8 @@ struct drm_radeon_cs {
 #define RADEON_INFO_SI_CP_DMA_COMPUTE	0x17
 /* CIK macrotile mode array */
 #define RADEON_INFO_CIK_MACROTILE_MODE_ARRAY	0x18
+/* query the number of render backends */
+#define RADEON_INFO_SI_NUM_RENDER_BACKENDS	0x19
 
 
 struct drm_radeon_info {
-- 
1.8.3.2