[PATCH v4 2/6] drm: simpledrm: add fbdev fallback support
David Herrmann
dh.herrmann at gmail.com
Sun Sep 1 06:36:48 PDT 2013
Create a simple fbdev device during SimpleDRM setup so legacy user-space
and fbcon can use it.
Signed-off-by: David Herrmann <dh.herrmann at gmail.com>
Tested-by: Stephen Warren <swarren at nvidia.com>
---
drivers/gpu/drm/simpledrm/Kconfig | 11 ++
drivers/gpu/drm/simpledrm/Makefile | 1 +
drivers/gpu/drm/simpledrm/simpledrm.h | 22 ++++
drivers/gpu/drm/simpledrm/simpledrm_fbdev.c | 153 ++++++++++++++++++++++++++++
drivers/gpu/drm/simpledrm/simpledrm_main.c | 2 +
5 files changed, 189 insertions(+)
create mode 100644 drivers/gpu/drm/simpledrm/simpledrm_fbdev.c
diff --git a/drivers/gpu/drm/simpledrm/Kconfig b/drivers/gpu/drm/simpledrm/Kconfig
index 35bcce8..eef2a36 100644
--- a/drivers/gpu/drm/simpledrm/Kconfig
+++ b/drivers/gpu/drm/simpledrm/Kconfig
@@ -12,7 +12,18 @@ config DRM_SIMPLEDRM
SimpleDRM supports "simple-framebuffer" DeviceTree objects and
compatible platform framebuffers.
+ If fbdev support is enabled, this driver will also provide an fbdev
+ compatibility layer.
+
If unsure, say Y.
To compile this driver as a module, choose M here: the
module will be called simpledrm.
+
+config DRM_SIMPLEDRM_FBDEV
+ bool
+ depends on DRM_SIMPLEDRM && FB
+ default y
+ select FB_CFB_FILLRECT
+ select FB_CFB_COPYAREA
+ select FB_CFB_IMAGEBLIT
diff --git a/drivers/gpu/drm/simpledrm/Makefile b/drivers/gpu/drm/simpledrm/Makefile
index ceb97eb..2144787 100644
--- a/drivers/gpu/drm/simpledrm/Makefile
+++ b/drivers/gpu/drm/simpledrm/Makefile
@@ -1,3 +1,4 @@
simpledrm-y := simpledrm_drv.o simpledrm_main.o simpledrm_mem.o
+simpledrm-$(CONFIG_DRM_SIMPLEDRM_FBDEV) += simpledrm_fbdev.o
obj-$(CONFIG_DRM_SIMPLEDRM) := simpledrm.o
diff --git a/drivers/gpu/drm/simpledrm/simpledrm.h b/drivers/gpu/drm/simpledrm/simpledrm.h
index 977b344..b854981 100644
--- a/drivers/gpu/drm/simpledrm/simpledrm.h
+++ b/drivers/gpu/drm/simpledrm/simpledrm.h
@@ -46,6 +46,9 @@ struct sdrm_device {
struct drm_encoder enc;
struct drm_connector conn;
struct drm_display_mode *mode;
+
+ /* fbdev */
+ struct fb_info *fbdev;
};
int sdrm_drm_load(struct drm_device *ddev, unsigned long flags);
@@ -86,4 +89,23 @@ struct sdrm_framebuffer {
#define to_sdrm_fb(x) container_of(x, struct sdrm_framebuffer, base)
+/* simpledrm fbdev helpers */
+
+#ifdef CONFIG_DRM_SIMPLEDRM_FBDEV
+
+void sdrm_fbdev_init(struct sdrm_device *sdrm);
+void sdrm_fbdev_cleanup(struct sdrm_device *sdrm);
+
+#else /* CONFIG_DRM_SIMPLEDRM_FBDEV */
+
+static inline void sdrm_fbdev_init(struct sdrm_device *sdrm)
+{
+}
+
+static inline void sdrm_fbdev_cleanup(struct sdrm_device *sdrm)
+{
+}
+
+#endif /* CONFIG_DRM_SIMPLEDRM_FBDEV */
+
#endif /* SDRM_DRV_H */
diff --git a/drivers/gpu/drm/simpledrm/simpledrm_fbdev.c b/drivers/gpu/drm/simpledrm/simpledrm_fbdev.c
new file mode 100644
index 0000000..7e2e4a2
--- /dev/null
+++ b/drivers/gpu/drm/simpledrm/simpledrm_fbdev.c
@@ -0,0 +1,153 @@
+/*
+ * SimpleDRM firmware framebuffer driver
+ * Copyright (c) 2012-2013 David Herrmann <dh.herrmann at gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ */
+
+/*
+ * fbdev compatibility layer
+ * We provide a basic fbdev device for the same framebuffer that is used for
+ * the pseudo CRTC.
+ */
+
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/fb.h>
+#include "simpledrm.h"
+
+struct sdrm_fbdev {
+ u32 palette[16];
+};
+
+static int sdrm_fbdev_setcolreg(u_int regno, u_int red, u_int green,
+ u_int blue, u_int transp, struct fb_info *info)
+{
+ u32 *pal = info->pseudo_palette;
+ u32 cr = red >> (16 - info->var.red.length);
+ u32 cg = green >> (16 - info->var.green.length);
+ u32 cb = blue >> (16 - info->var.blue.length);
+ u32 value;
+
+ if (regno >= 16)
+ return -EINVAL;
+
+ value = (cr << info->var.red.offset) |
+ (cg << info->var.green.offset) |
+ (cb << info->var.blue.offset);
+
+ if (info->var.transp.length > 0) {
+ u32 mask = (1 << info->var.transp.length) - 1;
+ mask <<= info->var.transp.offset;
+ value |= mask;
+ }
+
+ pal[regno] = value;
+
+ return 0;
+}
+
+static struct fb_ops sdrm_fbdev_ops = {
+ .owner = THIS_MODULE,
+ .fb_setcolreg = sdrm_fbdev_setcolreg,
+ .fb_fillrect = cfb_fillrect,
+ .fb_copyarea = cfb_copyarea,
+ .fb_imageblit = cfb_imageblit,
+};
+
+void sdrm_fbdev_init(struct sdrm_device *sdrm)
+{
+ struct sdrm_fbdev *fb;
+ struct fb_info *info;
+ int ret;
+
+ if (fb_get_options("simpledrmfb", NULL))
+ return;
+
+ info = framebuffer_alloc(sizeof(struct sdrm_fbdev), sdrm->ddev->dev);
+ if (!info)
+ goto err_out;
+
+ fb = info->par;
+ info->flags = FBINFO_DEFAULT | FBINFO_MISC_FIRMWARE;
+ info->pseudo_palette = fb->palette;
+ info->fbops = &sdrm_fbdev_ops;
+ info->screen_base = sdrm->fb_map;
+
+ strncpy(info->fix.id, "simpledrmfb", 15);
+ info->fix.type = FB_TYPE_PACKED_PIXELS;
+ info->fix.visual = FB_VISUAL_TRUECOLOR;
+ info->fix.accel = FB_ACCEL_NONE;
+ info->fix.smem_start = (unsigned long)sdrm->fb_base;
+ info->fix.smem_len = sdrm->fb_size;
+ info->fix.line_length = sdrm->fb_stride;
+
+ info->var.activate = FB_ACTIVATE_NOW;
+ info->var.vmode = FB_VMODE_NONINTERLACED;
+ info->var.bits_per_pixel = sdrm->fb_bpp;
+ info->var.height = -1;
+ info->var.width = -1;
+ info->var.xres = sdrm->fb_width;
+ info->var.yres = sdrm->fb_height;
+ info->var.xres_virtual = info->var.xres;
+ info->var.yres_virtual = info->var.yres;
+ info->var.red = sdrm->fb_sformat->red;
+ info->var.green = sdrm->fb_sformat->green;
+ info->var.blue = sdrm->fb_sformat->blue;
+ info->var.transp = sdrm->fb_sformat->transp;
+
+ /* some dummy values for timing to make fbset happy */
+ info->var.pixclock = 10000000 / info->var.xres * 1000 / info->var.yres;
+ info->var.left_margin = (info->var.xres / 8) & 0xf8;
+ info->var.right_margin = 32;
+ info->var.upper_margin = 16;
+ info->var.lower_margin = 4;
+ info->var.hsync_len = (info->var.xres / 8) & 0xf8;
+ info->var.vsync_len = 4;
+
+ info->apertures = alloc_apertures(1);
+ if (!info->apertures)
+ goto err_free;
+
+ info->apertures->ranges[0].base = (unsigned long)sdrm->fb_base;
+ info->apertures->ranges[0].size = sdrm->fb_size;
+
+ sdrm->fbdev = info;
+ ret = register_framebuffer(info);
+ if (ret < 0)
+ goto err_free;
+
+ dev_info(sdrm->ddev->dev, "fbdev frontend %s as fb%d\n",
+ info->fix.id, info->node);
+
+ return;
+
+err_free:
+ framebuffer_release(info);
+ sdrm->fbdev = NULL;
+err_out:
+ dev_warn(sdrm->ddev->dev, "cannot create fbdev frontend\n");
+}
+
+void sdrm_fbdev_cleanup(struct sdrm_device *sdrm)
+{
+ struct fb_info *info;
+
+ if (!sdrm->fbdev)
+ return;
+
+ dev_info(sdrm->ddev->dev, "fbdev cleanup\n");
+ info = sdrm->fbdev;
+ sdrm->fbdev = NULL;
+
+ if (unregister_framebuffer(info))
+ dev_warn(sdrm->ddev->dev, "unregister_framebuffer() failed, leaking fbdev device\n");
+ else
+ framebuffer_release(info);
+}
diff --git a/drivers/gpu/drm/simpledrm/simpledrm_main.c b/drivers/gpu/drm/simpledrm/simpledrm_main.c
index ae507e3..497542d 100644
--- a/drivers/gpu/drm/simpledrm/simpledrm_main.c
+++ b/drivers/gpu/drm/simpledrm/simpledrm_main.c
@@ -303,6 +303,7 @@ int sdrm_drm_load(struct drm_device *ddev, unsigned long flags)
if (ret)
goto err_cleanup;
+ sdrm_fbdev_init(sdrm);
return 0;
err_cleanup:
@@ -320,6 +321,7 @@ int sdrm_drm_unload(struct drm_device *ddev)
{
struct sdrm_device *sdrm = ddev->dev_private;
+ sdrm_fbdev_cleanup(sdrm);
drm_mode_config_cleanup(ddev);
sdrm_pdev_destroy(sdrm);
kfree(sdrm);
--
1.8.4
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