Modesetting for fbdevdrm supports a single display pipeline with CRTC, primary plane, encoder and connector.
The fbdev device would have been an ideal candidate for using |struct drm_simple_display_pipe|. To better illustrate the conversion from fbdev to DRM drivers, fbdevdrm used the regular DRM data structures instead.
Signed-off-by: Thomas Zimmermann tzimmermann@suse.de --- drivers/gpu/drm/fbdevdrm/Makefile | 1 + drivers/gpu/drm/fbdevdrm/fbdevdrm_device.c | 7 + drivers/gpu/drm/fbdevdrm/fbdevdrm_device.h | 2 + drivers/gpu/drm/fbdevdrm/fbdevdrm_drv.c | 4 +- drivers/gpu/drm/fbdevdrm/fbdevdrm_modeset.c | 430 ++++++++++++++++++++ drivers/gpu/drm/fbdevdrm/fbdevdrm_modeset.h | 36 ++ 6 files changed, 479 insertions(+), 1 deletion(-) create mode 100644 drivers/gpu/drm/fbdevdrm/fbdevdrm_modeset.c create mode 100644 drivers/gpu/drm/fbdevdrm/fbdevdrm_modeset.h
diff --git a/drivers/gpu/drm/fbdevdrm/Makefile b/drivers/gpu/drm/fbdevdrm/Makefile index fdfdb5233831..b8fab9d52faa 100644 --- a/drivers/gpu/drm/fbdevdrm/Makefile +++ b/drivers/gpu/drm/fbdevdrm/Makefile @@ -2,6 +2,7 @@ ccflags-y = -Iinclude/drm fbdevdrm-y := fbdevdrm_bo.o \ fbdevdrm_device.o \ fbdevdrm_drv.o \ + fbdevdrm_modeset.o \ fbdevdrm_ttm.o
obj-$(CONFIG_DRM_FBDEVDRM) += fbdevdrm.o diff --git a/drivers/gpu/drm/fbdevdrm/fbdevdrm_device.c b/drivers/gpu/drm/fbdevdrm/fbdevdrm_device.c index c8054eac271d..bb034f3d9392 100644 --- a/drivers/gpu/drm/fbdevdrm/fbdevdrm_device.c +++ b/drivers/gpu/drm/fbdevdrm/fbdevdrm_device.c @@ -37,10 +37,16 @@ int fbdevdrm_device_init(struct fbdevdrm_device *fdev, struct drm_driver *drv, if (ret) goto err_drm_dev_fini;
+ ret = fbdevdrm_modeset_init(&fdev->modeset, &fdev->dev, fb_info); + if (ret) + goto err_fbdevdrm_ttm_cleanup; + INIT_LIST_HEAD(&fdev->device_list);
return 0;
+err_fbdevdrm_ttm_cleanup: + fbdevdrm_ttm_cleanup(&fdev->ttm); err_drm_dev_fini: drm_dev_fini(&fdev->dev); return ret; @@ -55,6 +61,7 @@ void fbdevdrm_device_cleanup(struct fbdevdrm_device *fdev) "in device list\n"); }
+ fbdevdrm_modeset_cleanup(&fdev->modeset); fbdevdrm_ttm_cleanup(&fdev->ttm);
drm_dev_fini(dev); diff --git a/drivers/gpu/drm/fbdevdrm/fbdevdrm_device.h b/drivers/gpu/drm/fbdevdrm/fbdevdrm_device.h index 381d9cfb1450..4068d12e3270 100644 --- a/drivers/gpu/drm/fbdevdrm/fbdevdrm_device.h +++ b/drivers/gpu/drm/fbdevdrm/fbdevdrm_device.h @@ -16,6 +16,7 @@ #include <drm/drm_device.h> #include <linux/kernel.h> #include <linux/list.h> +#include "fbdevdrm_modeset.h" #include "fbdevdrm_ttm.h"
struct drm_driver; @@ -26,6 +27,7 @@ struct fbdevdrm_device { struct fb_info *fb_info;
struct fbdevdrm_ttm ttm; + struct fbdevdrm_modeset modeset;
struct list_head device_list; /* entry in global device list */ }; diff --git a/drivers/gpu/drm/fbdevdrm/fbdevdrm_drv.c b/drivers/gpu/drm/fbdevdrm/fbdevdrm_drv.c index 4724e3df6ace..dff9f44f05bd 100644 --- a/drivers/gpu/drm/fbdevdrm/fbdevdrm_drv.c +++ b/drivers/gpu/drm/fbdevdrm/fbdevdrm_drv.c @@ -148,7 +148,9 @@ static struct drm_driver fbdevdrm_drv = { .name = DRIVER_NAME, .desc = DRIVER_DESCRIPTION, .date = DRIVER_DATE, - .driver_features = DRIVER_GEM, + .driver_features = DRIVER_ATOMIC | + DRIVER_GEM | + DRIVER_MODESET, .fops = &driver_fops };
diff --git a/drivers/gpu/drm/fbdevdrm/fbdevdrm_modeset.c b/drivers/gpu/drm/fbdevdrm/fbdevdrm_modeset.c new file mode 100644 index 000000000000..585f3478f190 --- /dev/null +++ b/drivers/gpu/drm/fbdevdrm/fbdevdrm_modeset.c @@ -0,0 +1,430 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later + * + * One purpose of this driver is to allow for easy conversion of framebuffer + * drivers to DRM. As a special exception to the GNU GPL, you are allowed to + * relicense this file under the terms of a license of your choice if you're + * porting a framebuffer driver. In order to do so, update the SPDX license + * identifier to the new license and remove this exception. + * + * If you add code to this file, please ensure that it's compatible with the + * stated exception. + */ + +#include "fbdevdrm_modeset.h" +#include <drm/drm_atomic_helper.h> +#include <drm/drm_crtc_helper.h> +#include <drm/drm_device.h> +#include <drm/drm_fb_helper.h> +#include <drm/drm_gem_framebuffer_helper.h> +#include <drm/drm_modeset_helper.h> +#include <drm/drm_modeset_helper_vtables.h> +#include <drm/drm_probe_helper.h> +#include <linux/fb.h> + +/* + * CRTC + */ + +static enum drm_mode_status crtc_helper_mode_valid( + struct drm_crtc *crtc, const struct drm_display_mode *mode) +{ + return MODE_OK; +} + +static bool crtc_helper_mode_fixup(struct drm_crtc *crtc, + const struct drm_display_mode *mode, + struct drm_display_mode *adjusted_mode) +{ + return true; +} + +static void crtc_helper_mode_set_nofb(struct drm_crtc *crtc) +{ } + +static int crtc_helper_mode_set_base_atomic(struct drm_crtc *crtc, + struct drm_framebuffer *fb, + int x, int y, + enum mode_set_atomic mode) +{ + return 0; +} + +static int crtc_helper_atomic_check(struct drm_crtc *crtc, + struct drm_crtc_state *state) +{ + return 0; +} + +static void crtc_helper_atomic_begin( + struct drm_crtc *crtc, struct drm_crtc_state *old_crtc_state) +{ } + +static void crtc_helper_atomic_flush( + struct drm_crtc *crtc, struct drm_crtc_state *old_crtc_state) +{ } + +static void crtc_helper_atomic_enable( + struct drm_crtc *crtc, struct drm_crtc_state *old_crtc_state) +{ } + +static void crtc_helper_atomic_disable( + struct drm_crtc *crtc, struct drm_crtc_state *old_crtc_state) +{ } + +static const struct drm_crtc_helper_funcs fbdevdrm_crtc_helper_funcs = { + .dpms = NULL, /* legacy */ + .prepare = NULL, /* legacy */ + .commit = NULL, /* legacy */ + .mode_valid = crtc_helper_mode_valid, + .mode_fixup = crtc_helper_mode_fixup, + .mode_set = NULL, /* legacy */ + .mode_set_nofb = crtc_helper_mode_set_nofb, + .mode_set_base = NULL, /* legacy */ + .mode_set_base_atomic = crtc_helper_mode_set_base_atomic, + .disable = NULL, /* legacy */ + .atomic_check = crtc_helper_atomic_check, + .atomic_begin = crtc_helper_atomic_begin, + .atomic_flush = crtc_helper_atomic_flush, + .atomic_enable = crtc_helper_atomic_enable, + .atomic_disable = crtc_helper_atomic_disable, +}; + +static void crtc_destroy(struct drm_crtc *crtc) +{ } + +static int crtc_atomic_set_property(struct drm_crtc *crtc, + struct drm_crtc_state *state, + struct drm_property *property, + uint64_t val) +{ + return -EINVAL; +} + +static int crtc_atomic_get_property(struct drm_crtc *crtc, + const struct drm_crtc_state *state, + struct drm_property *property, + uint64_t *val) +{ + return -EINVAL; +} + +static int crtc_enable_vblank(struct drm_crtc *crtc) +{ + return -ENODEV; +} + +static void crtc_disable_vblank(struct drm_crtc *crtc) +{ } + +static const struct drm_crtc_funcs fbdevdrm_crtc_funcs = { + .reset = drm_atomic_helper_crtc_reset, + .cursor_set = NULL, /* not supported by fbdev */ + .cursor_set2 = NULL, + .cursor_move = NULL, + .gamma_set = NULL, /* not supported by fbdev */ + .destroy = crtc_destroy, + .set_config = drm_atomic_helper_set_config, + .page_flip = NULL, + .page_flip_target = NULL, + .set_property = NULL, /* unused in atomic drivers */ + .atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state, + .atomic_destroy_state = drm_atomic_helper_crtc_destroy_state, + .atomic_set_property = crtc_atomic_set_property, + .atomic_get_property = crtc_atomic_get_property, + .late_register = NULL, + .early_unregister = NULL, + .set_crc_source = NULL, + .atomic_print_state = NULL, + .get_vblank_counter = NULL, /* not supported by fbdev */ + .enable_vblank = crtc_enable_vblank, + .disable_vblank = crtc_disable_vblank +}; + +/* + * Encoder + */ + +static enum drm_mode_status encoder_helper_mode_valid( + struct drm_encoder *crtc, const struct drm_display_mode *mode) +{ + return MODE_OK; +} + +static bool encoder_helper_mode_fixup(struct drm_encoder *encoder, + const struct drm_display_mode *mode, + struct drm_display_mode *adjusted_mode) +{ + return true; +} + +static void encoder_helper_atomic_mode_set( + struct drm_encoder *encoder, struct drm_crtc_state *crtc_state, + struct drm_connector_state *conn_state) +{ } + +static void encoder_helper_disable(struct drm_encoder *encoder) +{ } + +static void encoder_helper_enable(struct drm_encoder *encoder) +{ } + +static int encoder_helper_atomic_check(struct drm_encoder *encoder, + struct drm_crtc_state *crtc_state, + struct drm_connector_state *conn_state) +{ + return 0; +} + +static const struct drm_encoder_helper_funcs fbdevdrm_encoder_helper_funcs = { + .dpms = NULL, /* legacy */ + .mode_valid = encoder_helper_mode_valid, + .mode_fixup = encoder_helper_mode_fixup, + .prepare = NULL, /* legacy */ + .commit = NULL, /* legacy */ + .mode_set = NULL, /* legacy */ + .atomic_mode_set = encoder_helper_atomic_mode_set, + .get_crtc = NULL, /* legacy */ + .detect = NULL, /* legacy */ + .disable = encoder_helper_disable, + .enable = encoder_helper_enable, + .atomic_check = encoder_helper_atomic_check +}; + +static void encoder_destroy(struct drm_encoder *encoder) +{ } + +static const struct drm_encoder_funcs fbdevdrm_encoder_funcs = { + .reset = NULL, + .destroy = encoder_destroy, + .late_register = NULL, + .early_unregister = NULL, +}; + +/* + * Connector + */ + +static int connector_helper_get_modes(struct drm_connector *connector) +{ + return 0; +} + +static int connector_helper_detect_ctx(struct drm_connector *connector, + struct drm_modeset_acquire_ctx *ctx, + bool force) +{ + return connector_status_connected; +} + +static enum drm_mode_status connector_helper_mode_valid( + struct drm_connector *connector, struct drm_display_mode *mode) +{ + return MODE_OK; +} + +static int connector_helper_atomic_check(struct drm_connector *connector, + struct drm_connector_state *state) +{ + return 0; +} + +static void connector_helper_atomic_commit(struct drm_connector *connector, + struct drm_connector_state *state) +{ } + +static const struct drm_connector_helper_funcs + fbdevdrm_connector_helper_funcs = { + .get_modes = connector_helper_get_modes, + .detect_ctx = connector_helper_detect_ctx, + .mode_valid = connector_helper_mode_valid, + .best_encoder = NULL, /* use default */ + .atomic_best_encoder = NULL, /* use best_encoder instead */ + .atomic_check = connector_helper_atomic_check, + .atomic_commit = connector_helper_atomic_commit +}; + +static enum drm_connector_status connector_detect( + struct drm_connector *connector, bool force) +{ + return connector_status_connected; +} + +static void connector_force(struct drm_connector *connector) +{ } + +static void connector_destroy(struct drm_connector *connector) +{ } + +static int connector_atomic_set_property(struct drm_connector *connector, + struct drm_connector_state *state, + struct drm_property *property, + uint64_t val) +{ + return -EINVAL; +} + +static int connector_atomic_get_property( + struct drm_connector *connector, + const struct drm_connector_state *state, struct drm_property *property, + uint64_t *val) +{ + return -EINVAL; +} + +static const struct drm_connector_funcs fbdevdrm_connector_funcs = { + .dpms = NULL, /* not used by atomic drivers */ + .reset = drm_atomic_helper_connector_reset, + .detect = connector_detect, + .force = connector_force, + .fill_modes = drm_helper_probe_single_connector_modes, + .set_property = NULL, + .late_register = NULL, + .early_unregister = NULL, + .destroy = connector_destroy, + .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state, + .atomic_destroy_state = drm_atomic_helper_connector_destroy_state, + .atomic_set_property = connector_atomic_set_property, + .atomic_get_property = connector_atomic_get_property, + .atomic_print_state = NULL +}; + +/* + * Mode config + */ + +static enum drm_mode_status mode_config_mode_valid( + struct drm_device *dev, const struct drm_display_mode *mode) +{ + return MODE_OK; +} + +static const struct drm_mode_config_funcs fbdevdrm_mode_config_funcs = { + .fb_create = drm_gem_fb_create, + .get_format_info = NULL, + /* DRM porting notes: the output_poll_changed callback is used by + * fb helpers to implement fbdev emulation. As fbdevdrm is built + * upon fbdev, this is basically the opposite. If you're porting + * an fbdev driver to DRM and enable fbdev emulation, this callback + * will become useful. + */ + .output_poll_changed = drm_fb_helper_output_poll_changed, + .mode_valid = mode_config_mode_valid, + .atomic_check = drm_atomic_helper_check, + .atomic_commit = drm_atomic_helper_commit, + .atomic_state_alloc = NULL, + .atomic_state_clear = NULL, + .atomic_state_free = NULL +}; + +/* + * Public interface + */ + +static int update_mode_config_from_fb_info(struct drm_mode_config* mode_config, struct fb_info *fb_info) +{ + /* DRM backporting notes: This function only exists to work around + * the fact that we don't know the hardware limitations. Here we + * test for the maximum supported resolution. If you're converting + * an fbdev driver to DRM, remove this function and simply fill in + * the actual hardware limits in the mode_config structure. + */ + + struct list_head *pos; + u32 xres = 0; + u32 yres = 0; + int num_modes = 0; + + list_for_each(pos, &fb_info->modelist) { + const struct fb_modelist *modelist = + container_of(pos, struct fb_modelist, list); + if (modelist->mode.xres > xres) + xres = modelist->mode.xres; + if (modelist->mode.yres > yres) + yres = modelist->mode.yres; + + ++num_modes; + } + + if (!xres || !yres) + return -ENODEV; + + mode_config->max_width = (int)xres; + mode_config->max_height = (int)yres; + mode_config->fb_base = fb_info->fix.smem_start; + + /* TODO: get preferred depth from screeninfo */ + mode_config->preferred_depth = 32; + + return 0; +} + +int fbdevdrm_modeset_init(struct fbdevdrm_modeset *modeset, + struct drm_device *dev, struct fb_info *fb_info) +{ + int ret; + + modeset->dev = dev; + modeset->fb_info = fb_info; + + drm_mode_config_init(dev); + ret = update_mode_config_from_fb_info(&dev->mode_config, fb_info); + if (ret) + goto err_drm_mode_config_cleanup; + dev->mode_config.funcs = &fbdevdrm_mode_config_funcs; + + /* One by one, we enable all stages of the display pipeline and + * connect them with each other. + */ + + ret = drm_crtc_init_with_planes(dev, &modeset->crtc, NULL, NULL, + &fbdevdrm_crtc_funcs, NULL); + if (ret) + goto err_drm_mode_config_cleanup; + drm_crtc_helper_add(&modeset->crtc, &fbdevdrm_crtc_helper_funcs); + + /* Use DRM_MODE_ENCODER_TYPE_DAC. It's true for many of the fbdev + * devices and doesn't imply hotplugging. */ + ret = drm_encoder_init(dev, &modeset->encoder, + &fbdevdrm_encoder_funcs, + DRM_MODE_ENCODER_DAC, NULL); + if (ret) + goto err_drm_mode_config_cleanup; + drm_encoder_helper_add(&modeset->encoder, + &fbdevdrm_encoder_helper_funcs); + + modeset->encoder.possible_crtcs = (1ul << modeset->crtc.index); + + ret = drm_connector_init(dev, &modeset->connector, + &fbdevdrm_connector_funcs, + DRM_MODE_CONNECTOR_VGA); + if (ret) + goto err_drm_mode_config_cleanup; + drm_connector_helper_add(&modeset->connector, + &fbdevdrm_connector_helper_funcs); + + ret = drm_connector_register(&modeset->connector); + if (ret < 0) + goto err_drm_mode_config_cleanup; + + ret = drm_connector_attach_encoder(&modeset->connector, + &modeset->encoder); + if (ret) + goto err_drm_mode_config_cleanup; + + /* Final step: resetting the device's mode config creates + * state for all objects in the mode-setting pipeline. + */ + drm_mode_config_reset(dev); + + return 0; + +err_drm_mode_config_cleanup: + /* Also removes all CRTCs, encoders and connectors that we added. */ + drm_mode_config_cleanup(dev); + return ret; +} + +void fbdevdrm_modeset_cleanup(struct fbdevdrm_modeset *modeset) +{ + drm_mode_config_cleanup(modeset->dev); +} diff --git a/drivers/gpu/drm/fbdevdrm/fbdevdrm_modeset.h b/drivers/gpu/drm/fbdevdrm/fbdevdrm_modeset.h new file mode 100644 index 000000000000..21e87caa8196 --- /dev/null +++ b/drivers/gpu/drm/fbdevdrm/fbdevdrm_modeset.h @@ -0,0 +1,36 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later + * + * One purpose of this driver is to allow for easy conversion of framebuffer + * drivers to DRM. As a special exception to the GNU GPL, you are allowed to + * relicense this file under the terms of a license of your choice if you're + * porting a framebuffer driver. In order to do so, update the SPDX license + * identifier to the new license and remove this exception. + * + * If you add code to this file, please ensure that it's compatible with the + * stated exception. + */ + +#ifndef FBDEVDRM_MODESET_H +#define FBDEVDRM_MODESET_H + +#include <drm/drm_connector.h> +#include <drm/drm_crtc.h> +#include <drm/drm_encoder.h> + +struct drm_device; +struct fb_info; + +struct fbdevdrm_modeset { + struct drm_crtc crtc; + struct drm_encoder encoder; + struct drm_connector connector; + + struct drm_device *dev; + struct fb_info *fb_info; +}; + +int fbdevdrm_modeset_init(struct fbdevdrm_modeset *modeset, + struct drm_device *dev, struct fb_info *fb_info); +void fbdevdrm_modeset_cleanup(struct fbdevdrm_modeset *modeset); + +#endif