DRM: add DRM Driver for Samsung SoC EXYNOS4210.

This patch is a DRM Driver for Samsung SoC Exynos4210 and now enables
only FIMD yet but we will add HDMI support also in the future.

this patch is based on git repository below:
git://people.freedesktop.org/~airlied/linux.git
branch name: drm-next
commit-id: 88ef4e3f4f616462b78a7838eb3ffc3818d30f67

you can refer to our working repository below:
http://git.infradead.org/users/kmpark/linux-2.6-samsung
branch name: samsung-drm

We tried to re-use lowlevel codes of the FIMD driver(s3c-fb.c
based on Linux framebuffer) but couldn't so because lowlevel codes
of s3c-fb.c are included internally and so FIMD module of this driver has
its own lowlevel codes.

We used GEM framework for buffer management and DMA APIs(dma_alloc_*)
for buffer allocation so we can allocate physically continuous memory
for DMA through it and also we could use CMA later if CMA is applied to
mainline.

Refer to this link for CMA(Continuous Memory Allocator):
http://lkml.org/lkml/2011/7/20/45

this driver supports only physically continuous memory(non-iommu).

Links to previous versions of the patchset:
v1: < https://lwn.net/Articles/454380/ >
v2: < http://www.spinics.net/lists/kernel/msg1224275.html >
v3: < http://www.spinics.net/lists/dri-devel/msg13755.html >
v4: < http://permalink.gmane.org/gmane.comp.video.dri.devel/60439 >
v5: < http://comments.gmane.org/gmane.comp.video.dri.devel/60802 >

Changelog v2:
DRM: add DRM_IOCTL_SAMSUNG_GEM_MMAP ioctl command.

    this feature maps user address space to physical memory region
    once user application requests DRM_IOCTL_SAMSUNG_GEM_MMAP ioctl.

DRM: code clean and add exception codes.

Changelog v3:
DRM: Support multiple irq.

    FIMD and HDMI have their own irq handler but DRM Framework can regiter
    only one irq handler this patch supports mutiple irq for Samsung SoC.

DRM: Consider modularization.

    each DRM, FIMD could be built as a module.

DRM: Have indenpendent crtc object.

    crtc isn't specific to SoC Platform so this patch gets a crtc
    to be used as common object.
    created crtc could be attached to any encoder object.

DRM: code clean and add exception codes.

Changelog v4:
DRM: remove is_defult from samsung_fb.

    is_default isn't used for default framebuffer.

DRM: code refactoring to fimd module.
    this patch is be considered with multiple display objects and
    would use its own request_irq() to register a irq handler instead of
    drm framework's one.

DRM: remove find_samsung_drm_gem_object()

DRM: move kernel private data structures and definitions to driver folder.

    samsung_drm.h would contain only public information for userspace
    ioctl interface.

DRM: code refactoring to gem modules.
    buffer module isn't dependent of gem module anymore.

DRM: fixed security issue.

DRM: remove encoder porinter from specific connector.

    samsung connector doesn't need to have generic encoder.

DRM: code clean and add exception codes.

Changelog v5:
DRM: updated fimd(display controller) driver.
    added various pixel formats, color key and pixel blending features.

DRM: removed end_buf_off from samsung_drm_overlay structure.
    this variable isn't used and end buffer address would be
    calculated by each sub driver.

DRM: use generic function for mmap_offset.
    replaced samsung_drm_gem_create_mmap_offset() and
    samsung_drm_free_mmap_offset() with generic ones applied
    to mainline recentrly.

DRM: removed unnecessary codes and added exception codes.

DRM: added comments and code clean.

Changelog v6:
DRM: added default config options.

DRM: added padding for 64-bit align.

DRM: changed prefix 'samsung' to 'exynos'

Signed-off-by: Inki Dae <inki.dae@samsung.com>
Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>
Signed-off-by: Seung-Woo Kim <sw0312.kim@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Dave Airlie <airlied@redhat.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 344 insertions, 0 deletions

diff --git a/drivers/gpu/drm/exynos/exynos_drm_crtc.c b/drivers/gpu/drm/exynos/exynos_drm_crtc.c
new file mode 100644
index 000000000000..683ceb0f5277
--- /dev/null
+++ b/drivers/gpu/drm/exynos/exynos_drm_crtc.c
@@ -0,0 +1,344 @@
+/* exynos_drm_crtc.c
+ *
+ * Copyright (c) 2011 Samsung Electronics Co., Ltd.
+ * Authors:
+ *	Inki Dae <inki.dae@samsung.com>
+ *	Joonyoung Shim <jy0922.shim@samsung.com>
+ *	Seung-Woo Kim <sw0312.kim@samsung.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include "drmP.h"
+#include "drm_crtc_helper.h"
+
+#include "exynos_drm_drv.h"
+#include "exynos_drm_fb.h"
+#include "exynos_drm_encoder.h"
+
+#define to_exynos_crtc(x)	container_of(x, struct exynos_drm_crtc,\
+				drm_crtc)
+
+/*
+ * @fb_x: horizontal position from framebuffer base
+ * @fb_y: vertical position from framebuffer base
+ * @base_x: horizontal position from screen base
+ * @base_y: vertical position from screen base
+ * @crtc_w: width of crtc
+ * @crtc_h: height of crtc
+ */
+struct exynos_drm_crtc_pos {
+	unsigned int fb_x;
+	unsigned int fb_y;
+	unsigned int base_x;
+	unsigned int base_y;
+	unsigned int crtc_w;
+	unsigned int crtc_h;
+};
+
+/*
+ * Exynos specific crtc structure.
+ *
+ * @drm_crtc: crtc object.
+ * @overlay: contain information common to display controller and hdmi and
+ *	contents of this overlay object would be copied to sub driver size.
+ * @pipe: a crtc index created at load() with a new crtc object creation
+ *	and the crtc object would be set to private->crtc array
+ *	to get a crtc object corresponding to this pipe from private->crtc
+ *	array when irq interrupt occured. the reason of using this pipe is that
+ *	drm framework doesn't support multiple irq yet.
+ *	we can refer to the crtc to current hardware interrupt occured through
+ *	this pipe value.
+ */
+struct exynos_drm_crtc {
+	struct drm_crtc			drm_crtc;
+	struct exynos_drm_overlay	overlay;
+	unsigned int			pipe;
+};
+
+void exynos_drm_crtc_apply(struct drm_crtc *crtc)
+{
+	struct exynos_drm_crtc *exynos_crtc = to_exynos_crtc(crtc);
+	struct exynos_drm_overlay *overlay = &exynos_crtc->overlay;
+
+	exynos_drm_fn_encoder(crtc, overlay,
+			exynos_drm_encoder_crtc_mode_set);
+	exynos_drm_fn_encoder(crtc, NULL, exynos_drm_encoder_crtc_commit);
+}
+
+static void exynos_drm_overlay_update(struct exynos_drm_overlay *overlay,
+				       struct drm_framebuffer *fb,
+				       struct drm_display_mode *mode,
+				       struct exynos_drm_crtc_pos *pos)
+{
+	struct exynos_drm_buffer_info buffer_info;
+	unsigned int actual_w = pos->crtc_w;
+	unsigned int actual_h = pos->crtc_h;
+	unsigned int hw_w;
+	unsigned int hw_h;
+
+	/* update buffer address of framebuffer. */
+	exynos_drm_fb_update_buf_off(fb, pos->fb_x, pos->fb_y, &buffer_info);
+	overlay->paddr = buffer_info.paddr;
+	overlay->vaddr = buffer_info.vaddr;
+
+	hw_w = mode->hdisplay - pos->base_x;
+	hw_h = mode->vdisplay - pos->base_y;
+
+	if (actual_w > hw_w)
+		actual_w = hw_w;
+	if (actual_h > hw_h)
+		actual_h = hw_h;
+
+	overlay->offset_x = pos->base_x;
+	overlay->offset_y = pos->base_y;
+	overlay->width = actual_w;
+	overlay->height = actual_h;
+	overlay->bpp = fb->bits_per_pixel;
+
+	DRM_DEBUG_KMS("overlay : offset_x/y(%d,%d), width/height(%d,%d)",
+			overlay->offset_x, overlay->offset_y,
+			overlay->width, overlay->height);
+
+	overlay->buf_offsize = fb->width - actual_w;
+	overlay->line_size = actual_w;
+}
+
+static int exynos_drm_crtc_update(struct drm_crtc *crtc)
+{
+	struct exynos_drm_crtc *exynos_crtc;
+	struct exynos_drm_overlay *overlay;
+	struct exynos_drm_crtc_pos pos;
+	struct drm_display_mode *mode = &crtc->mode;
+	struct drm_framebuffer *fb = crtc->fb;
+
+	if (!mode || !fb)
+		return -EINVAL;
+
+	exynos_crtc = to_exynos_crtc(crtc);
+	overlay = &exynos_crtc->overlay;
+
+	memset(&pos, 0, sizeof(struct exynos_drm_crtc_pos));
+	pos.fb_x = crtc->x;
+	pos.fb_y = crtc->y;
+	pos.crtc_w = fb->width - crtc->x;
+	pos.crtc_h = fb->height - crtc->y;
+
+	exynos_drm_overlay_update(overlay, crtc->fb, mode, &pos);
+
+	return 0;
+}
+
+static void exynos_drm_crtc_dpms(struct drm_crtc *crtc, int mode)
+{
+	DRM_DEBUG_KMS("%s\n", __FILE__);
+
+	/* TODO */
+}
+
+static void exynos_drm_crtc_prepare(struct drm_crtc *crtc)
+{
+	DRM_DEBUG_KMS("%s\n", __FILE__);
+
+	/* drm framework doesn't check NULL. */
+}
+
+static void exynos_drm_crtc_commit(struct drm_crtc *crtc)
+{
+	DRM_DEBUG_KMS("%s\n", __FILE__);
+
+	/* drm framework doesn't check NULL. */
+}
+
+static bool
+exynos_drm_crtc_mode_fixup(struct drm_crtc *crtc,
+			    struct drm_display_mode *mode,
+			    struct drm_display_mode *adjusted_mode)
+{
+	DRM_DEBUG_KMS("%s\n", __FILE__);
+
+	/* drm framework doesn't check NULL */
+	return true;
+}
+
+static int
+exynos_drm_crtc_mode_set(struct drm_crtc *crtc, struct drm_display_mode *mode,
+			  struct drm_display_mode *adjusted_mode, int x, int y,
+			  struct drm_framebuffer *old_fb)
+{
+	DRM_DEBUG_KMS("%s\n", __FILE__);
+
+	mode = adjusted_mode;
+
+	return exynos_drm_crtc_update(crtc);
+}
+
+static int exynos_drm_crtc_mode_set_base(struct drm_crtc *crtc, int x, int y,
+					  struct drm_framebuffer *old_fb)
+{
+	int ret;
+
+	DRM_DEBUG_KMS("%s\n", __FILE__);
+
+	ret = exynos_drm_crtc_update(crtc);
+	if (ret)
+		return ret;
+
+	exynos_drm_crtc_apply(crtc);
+
+	return ret;
+}
+
+static void exynos_drm_crtc_load_lut(struct drm_crtc *crtc)
+{
+	DRM_DEBUG_KMS("%s\n", __FILE__);
+	/* drm framework doesn't check NULL */
+}
+
+static struct drm_crtc_helper_funcs exynos_crtc_helper_funcs = {
+	.dpms		= exynos_drm_crtc_dpms,
+	.prepare	= exynos_drm_crtc_prepare,
+	.commit		= exynos_drm_crtc_commit,
+	.mode_fixup	= exynos_drm_crtc_mode_fixup,
+	.mode_set	= exynos_drm_crtc_mode_set,
+	.mode_set_base	= exynos_drm_crtc_mode_set_base,
+	.load_lut	= exynos_drm_crtc_load_lut,
+};
+
+static int exynos_drm_crtc_page_flip(struct drm_crtc *crtc,
+				      struct drm_framebuffer *fb,
+				      struct drm_pending_vblank_event *event)
+{
+	struct drm_device *dev = crtc->dev;
+	struct exynos_drm_private *dev_priv = dev->dev_private;
+	struct exynos_drm_crtc *exynos_crtc = to_exynos_crtc(crtc);
+	struct drm_framebuffer *old_fb = crtc->fb;
+	int ret = -EINVAL;
+
+	DRM_DEBUG_KMS("%s\n", __FILE__);
+
+	mutex_lock(&dev->struct_mutex);
+
+	if (event && !dev_priv->pageflip_event) {
+		list_add_tail(&event->base.link,
+				&dev_priv->pageflip_event_list);
+
+		ret = drm_vblank_get(dev, exynos_crtc->pipe);
+		if (ret) {
+			DRM_DEBUG("failed to acquire vblank counter\n");
+			goto out;
+		}
+
+		crtc->fb = fb;
+		ret = exynos_drm_crtc_update(crtc);
+		if (ret) {
+			crtc->fb = old_fb;
+			drm_vblank_put(dev, exynos_crtc->pipe);
+			dev_priv->pageflip_event = false;
+
+			goto out;
+		}
+
+		dev_priv->pageflip_event = true;
+	}
+out:
+	mutex_unlock(&dev->struct_mutex);
+	return ret;
+}
+
+static void exynos_drm_crtc_destroy(struct drm_crtc *crtc)
+{
+	struct exynos_drm_crtc *exynos_crtc = to_exynos_crtc(crtc);
+	struct exynos_drm_private *private = crtc->dev->dev_private;
+
+	DRM_DEBUG_KMS("%s\n", __FILE__);
+
+	private->crtc[exynos_crtc->pipe] = NULL;
+
+	drm_crtc_cleanup(crtc);
+	kfree(exynos_crtc);
+}
+
+static struct drm_crtc_funcs exynos_crtc_funcs = {
+	.set_config	= drm_crtc_helper_set_config,
+	.page_flip	= exynos_drm_crtc_page_flip,
+	.destroy	= exynos_drm_crtc_destroy,
+};
+
+struct exynos_drm_overlay *get_exynos_drm_overlay(struct drm_device *dev,
+		struct drm_crtc *crtc)
+{
+	struct exynos_drm_crtc *exynos_crtc = to_exynos_crtc(crtc);
+
+	return &exynos_crtc->overlay;
+}
+
+int exynos_drm_crtc_create(struct drm_device *dev, unsigned int nr)
+{
+	struct exynos_drm_crtc *exynos_crtc;
+	struct exynos_drm_private *private = dev->dev_private;
+	struct drm_crtc *crtc;
+
+	DRM_DEBUG_KMS("%s\n", __FILE__);
+
+	exynos_crtc = kzalloc(sizeof(*exynos_crtc), GFP_KERNEL);
+	if (!exynos_crtc) {
+		DRM_ERROR("failed to allocate exynos crtc\n");
+		return -ENOMEM;
+	}
+
+	exynos_crtc->pipe = nr;
+	crtc = &exynos_crtc->drm_crtc;
+
+	private->crtc[nr] = crtc;
+
+	drm_crtc_init(dev, crtc, &exynos_crtc_funcs);
+	drm_crtc_helper_add(crtc, &exynos_crtc_helper_funcs);
+
+	return 0;
+}
+
+int exynos_drm_crtc_enable_vblank(struct drm_device *dev, int crtc)
+{
+	struct exynos_drm_private *private = dev->dev_private;
+
+	DRM_DEBUG_KMS("%s\n", __FILE__);
+
+	exynos_drm_fn_encoder(private->crtc[crtc], &crtc,
+			exynos_drm_enable_vblank);
+
+	return 0;
+}
+
+void exynos_drm_crtc_disable_vblank(struct drm_device *dev, int crtc)
+{
+	struct exynos_drm_private *private = dev->dev_private;
+
+	DRM_DEBUG_KMS("%s\n", __FILE__);
+
+	exynos_drm_fn_encoder(private->crtc[crtc], &crtc,
+			exynos_drm_disable_vblank);
+}
+
+MODULE_AUTHOR("Inki Dae <inki.dae@samsung.com>");
+MODULE_AUTHOR("Joonyoung Shim <jy0922.shim@samsung.com>");
+MODULE_AUTHOR("Seung-Woo Kim <sw0312.kim@samsung.com>");
+MODULE_DESCRIPTION("Samsung SoC DRM CRTC Driver");
+MODULE_LICENSE("GPL");