[PATCH 4/5] drm/amdgpu: Add module param to control SI support

[Felix Kuehling]

If AMDGPU supports SI, add a module parameter to control SI
support. It's off by default in AMDGPU as long as SI suppost is
experimental, while it is on by default in radeon.

Signed-off-by: Felix Kuehling <Felix.Kuehling at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu.h     |  3 +++
 drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c |  6 ++++++
 drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c | 17 +++++++++++++++++
 3 files changed, 26 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
index be1cb3b..de7e409 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
@@ -114,6 +114,9 @@
 extern int amdgpu_param_buf_per_se;
 extern int amdgpu_job_hang_limit;
 
+#ifdef CONFIG_DRM_AMDGPU_SI
+extern int amdgpu_si_support;
+#endif
 #ifdef CONFIG_DRM_AMDGPU_CIK
 extern int amdgpu_cik_support;
 #endif
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
index f131ac2..24297a0 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
@@ -241,6 +241,12 @@
 MODULE_PARM_DESC(job_hang_limit, "how much time allow a job hang and not drop it (default 0)");
 module_param_named(job_hang_limit, amdgpu_job_hang_limit, int ,0444);
 
+#ifdef CONFIG_DRM_AMDGPU_SI
+int amdgpu_si_support = 1;
+MODULE_PARM_DESC(si_support, "SI support (1 = enabled, 0 = disabled (default))");
+module_param_named(si_support, amdgpu_si_support, int, 0444);
+#endif
+
 #ifdef CONFIG_DRM_AMDGPU_CIK
 int amdgpu_cik_support = 1;
 MODULE_PARM_DESC(cik_support, "CIK support (1 = enabled (default), 0 = disabled)");
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
index a2171c3..f418fa4 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
@@ -88,6 +88,23 @@ int amdgpu_driver_load_kms(struct drm_device *dev, unsigned long flags)
 	struct amdgpu_device *adev;
 	int r, acpi_status;
 
+#ifdef CONFIG_DRM_AMDGPU_SI
+	if (!amdgpu_si_support) {
+		switch (flags & AMD_ASIC_MASK) {
+		case CHIP_TAHITI:
+		case CHIP_PITCAIRN:
+		case CHIP_VERDE:
+		case CHIP_OLAND:
+		case CHIP_HAINAN:
+			dev_info(dev->dev,
+				 "SI support provided by radeon.\n");
+			dev_info(dev->dev,
+		"Use radeon.si_support=0 amdgpu.si_support=1 to override.\n"
+				);
+			return -ENODEV;
+		}
+	}
+#endif
 #ifdef CONFIG_DRM_AMDGPU_CIK
 	if (!amdgpu_cik_support) {
 		switch (flags & AMD_ASIC_MASK) {
-- 
1.9.1