From b5c189473dba2cffc9e4df310ce5c86ceca99a94 Mon Sep 17 00:00:00 2001
From: Jammy Zhou <Jammy.Zhou@amd.com>
Date: Tue, 13 Dec 2016 12:32:39 +0900
Subject: [PATCH] Use render node for DRI3 if available
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Signed-off-by: Jammy Zhou <Jammy.Zhou@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
[ Second attempt, let's see if there's any fallout this time... ]
---
 src/amdgpu_dri3.c  | 37 ++++++++++++++++++++++++++++++++++---
 src/amdgpu_probe.h |  1 +
 2 files changed, 35 insertions(+), 3 deletions(-)

diff --git a/src/amdgpu_dri3.c b/src/amdgpu_dri3.c
index f87c014..87e3d85 100644
--- a/src/amdgpu_dri3.c
+++ b/src/amdgpu_dri3.c
@@ -40,9 +40,7 @@
 #include <errno.h>
 #include <libgen.h>
 
-
-static int
-amdgpu_dri3_open(ScreenPtr screen, RRProviderPtr provider, int *out)
+static int open_master_node(ScreenPtr screen, int *out)
 {
 	ScrnInfoPtr scrn = xf86ScreenToScrn(screen);
 	AMDGPUEntPtr pAMDGPUEnt = AMDGPUEntPriv(scrn);
@@ -88,6 +86,36 @@ amdgpu_dri3_open(ScreenPtr screen, RRProviderPtr provider, int *out)
 	return Success;
 }
 
+static int open_render_node(ScreenPtr screen, int *out)
+{
+	ScrnInfoPtr scrn = xf86ScreenToScrn(screen);
+	AMDGPUEntPtr pAMDGPUEnt = AMDGPUEntPriv(scrn);
+	int fd;
+
+	fd = open(pAMDGPUEnt->render_node, O_RDWR | O_CLOEXEC);
+	if (fd < 0)
+		return BadAlloc;
+
+	*out = fd;
+	return Success;
+}
+
+static int
+amdgpu_dri3_open(ScreenPtr screen, RRProviderPtr provider, int *out)
+{
+	ScrnInfoPtr scrn = xf86ScreenToScrn(screen);
+	AMDGPUEntPtr pAMDGPUEnt = AMDGPUEntPriv(scrn);
+	int ret = BadAlloc;
+
+	if (pAMDGPUEnt->render_node)
+		ret = open_render_node(screen, out);
+
+	if (ret != Success)
+		ret = open_master_node(screen, out);
+
+	return ret;
+}
+
 #if DRI3_SCREEN_INFO_VERSION >= 1 && XORG_VERSION_CURRENT <= XORG_VERSION_NUMERIC(1,18,99,1,0)
 
 static int
@@ -229,6 +257,9 @@ Bool
 amdgpu_dri3_screen_init(ScreenPtr screen)
 {
 	ScrnInfoPtr scrn = xf86ScreenToScrn(screen);
+	AMDGPUEntPtr pAMDGPUEnt = AMDGPUEntPriv(scrn);
+
+	pAMDGPUEnt->render_node = drmGetRenderDeviceNameFromFd(pAMDGPUEnt->fd);
 
 	if (!dri3_screen_init(screen, &amdgpu_dri3_screen_info)) {
 		xf86DrvMsg(scrn->scrnIndex, X_WARNING,
diff --git a/src/amdgpu_probe.h b/src/amdgpu_probe.h
index 0302d02..0f43233 100644
--- a/src/amdgpu_probe.h
+++ b/src/amdgpu_probe.h
@@ -68,6 +68,7 @@ typedef struct {
 	ScrnInfoPtr primary_scrn;
 	ScrnInfoPtr secondary_scrn;
 	struct xf86_platform_device *platform_dev;
+	char *render_node;
 } AMDGPUEntRec, *AMDGPUEntPtr;
 
 extern const OptionInfoRec *AMDGPUOptionsWeak(void);