1 files changed, 68 insertions, 0 deletions
diff --git a/lib/gem_msm.c b/lib/gem_msm.c
new file mode 100644
index 00000000..2160f443
--- /dev/null
+++ b/lib/gem_msm.c
@@ -0,0 +1,68 @@
+#include "gem_msm.h"
+#include "drm-uapi/msm_drm.h"
+
+#include "drm.h"
+
+static int gem_msm_mmap(void **ptr, int drm_fd, uint32_t gem_handle, size_t size)
+{
+	struct drm_msm_gem_cpu_prep gem_prep = {
+		.handle = gem_handle,
+		.op = MSM_PREP_READ,
+		.timeout = { .tv_sec = 1, .tv_nsec = 0 }
+	};
+
+	if (drmIoctl(drm_fd, DRM_IOCTL_MSM_GEM_CPU_PREP, &gem_prep))
+	{
+		return -1;
+	}
+
+	struct drm_msm_gem_info gem_info = {
+		.handle = gem_handle,
+		.flags = 0,
+		.offset = 0
+	};
+
+	if (drmIoctl(drm_fd, DRM_IOCTL_MSM_GEM_INFO, &gem_info))
+	{
+		return -1;
+	}
+
+	void *const k_addr = 0;
+	const int k_prot = PROT_READ | PROT_WRITE;
+	const int k_flags = MAP_SHARED;
+
+	void *ret = mmap(k_addr, size, k_prot, k_flags, drm_fd, gem_info.offset);
+
+	if (ret == MAP_FAILED)
+	{
+		return -1;
+	}
+
+	*ptr = ret;
+
+	return 0;
+}
+
+static int gem_msm_munmap(int drm_fd, uint32_t gem_handle, void *ptr, size_t size)
+{
+	if (munmap(ptr, size))
+	{
+		return -1;
+	}
+
+	struct drm_msm_gem_cpu_fini gem_fini = {
+		.handle = gem_handle
+	};
+
+	if (drmIoctl(drm_fd, DRM_IOCTL_MSM_GEM_CPU_FINI, &gem_fini))
+	{
+		return -1;
+	}
+
+	return 0;
+}
+
+struct gem_driver gem_msm_driver = {
+	.mmap = gem_msm_mmap,
+	.munmap = gem_msm_munmap
+};