--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <linux/aperture.h>
+#include <linux/coreboot.h>
+#include <linux/minmax.h>
+#include <linux/platform_device.h>
+
+#include <drm/clients/drm_client_setup.h>
+#include <drm/drm_atomic.h>
+#include <drm/drm_atomic_state_helper.h>
+#include <drm/drm_connector.h>
+#include <drm/drm_damage_helper.h>
+#include <drm/drm_device.h>
+#include <drm/drm_drv.h>
+#include <drm/drm_fbdev_shmem.h>
+#include <drm/drm_framebuffer.h>
+#include <drm/drm_gem_atomic_helper.h>
+#include <drm/drm_gem_framebuffer_helper.h>
+#include <drm/drm_gem_shmem_helper.h>
+#include <drm/drm_managed.h>
+#include <drm/drm_modeset_helper_vtables.h>
+#include <drm/drm_print.h>
+#include <drm/drm_probe_helper.h>
+
+#include "drm_sysfb_helper.h"
+
+#define DRIVER_NAME "corebootdrm"
+#define DRIVER_DESC "DRM driver for Coreboot framebuffers"
+#define DRIVER_MAJOR 1
+#define DRIVER_MINOR 0
+
+static const struct drm_format_info *
+corebootdrm_get_format_fb(struct drm_device *dev, const struct lb_framebuffer *fb)
+{
+ static const struct drm_sysfb_format formats[] = {
+ { PIXEL_FORMAT_XRGB1555, DRM_FORMAT_XRGB1555, },
+ { PIXEL_FORMAT_RGB565, DRM_FORMAT_RGB565, },
+ { PIXEL_FORMAT_RGB888, DRM_FORMAT_RGB888, },
+ { PIXEL_FORMAT_XRGB8888, DRM_FORMAT_XRGB8888, },
+ { PIXEL_FORMAT_XBGR8888, DRM_FORMAT_XBGR8888, },
+ { PIXEL_FORMAT_XRGB2101010, DRM_FORMAT_XRGB2101010, },
+ };
+ const struct pixel_format pixel = {
+ .bits_per_pixel = fb->bits_per_pixel,
+ .indexed = false,
+ .alpha = {
+ .offset = 0,
+ .length = 0,
+ },
+ .red = {
+ .offset = fb->red_mask_pos,
+ .length = fb->red_mask_size,
+ },
+ .green = {
+ .offset = fb->green_mask_pos,
+ .length = fb->green_mask_size,
+ },
+ .blue = {
+ .offset = fb->blue_mask_pos,
+ .length = fb->blue_mask_size,
+ },
+ };
+
+ return drm_sysfb_get_format(dev, formats, ARRAY_SIZE(formats), &pixel);
+}
+
+static int corebootdrm_get_width_fb(struct drm_device *dev, const struct lb_framebuffer *fb)
+{
+ return drm_sysfb_get_validated_int0(dev, "width", fb->x_resolution, INT_MAX);
+}
+
+static int corebootdrm_get_height_fb(struct drm_device *dev, const struct lb_framebuffer *fb)
+{
+ return drm_sysfb_get_validated_int0(dev, "height", fb->y_resolution, INT_MAX);
+}
+
+static int corebootdrm_get_pitch_fb(struct drm_device *dev, const struct drm_format_info *format,
+ unsigned int width, const struct lb_framebuffer *fb)
+{
+ u64 bytes_per_line = fb->bytes_per_line;
+
+ if (!bytes_per_line)
+ bytes_per_line = drm_format_info_min_pitch(format, 0, width);
+
+ return drm_sysfb_get_validated_int0(dev, "pitch", bytes_per_line, INT_MAX);
+}
+
+static resource_size_t corebootdrm_get_size_fb(struct drm_device *dev, unsigned int height,
+ unsigned int pitch,
+ const struct lb_framebuffer *fb)
+{
+ resource_size_t size;
+
+ if (check_mul_overflow(height, pitch, &size))
+ return 0;
+
+ return size;
+}
+
+static phys_addr_t corebootdrm_get_address_fb(struct drm_device *dev, resource_size_t size,
+ const struct lb_framebuffer *fb)
+{
+ if (size > PHYS_ADDR_MAX)
+ return 0;
+ if (!fb->physical_address)
+ return 0;
+ if (fb->physical_address > (PHYS_ADDR_MAX - size))
+ return 0;
+
+ return fb->physical_address;
+}
+
+/*
+ * Simple Framebuffer device
+ */
+
+struct corebootdrm_device {
+ struct drm_sysfb_device sysfb;
+
+ /* modesetting */
+ u32 formats[DRM_SYSFB_PLANE_NFORMATS(1)];
+ struct drm_plane primary_plane;
+ struct drm_crtc crtc;
+ struct drm_encoder encoder;
+ struct drm_connector connector;
+};
+
+/*
+ * Modesetting
+ */
+
+static const u64 corebootdrm_primary_plane_format_modifiers[] = {
+ DRM_SYSFB_PLANE_FORMAT_MODIFIERS,
+};
+
+static const struct drm_plane_helper_funcs corebootdrm_primary_plane_helper_funcs = {
+ DRM_SYSFB_PLANE_HELPER_FUNCS,
+};
+
+static const struct drm_plane_funcs corebootdrm_primary_plane_funcs = {
+ DRM_SYSFB_PLANE_FUNCS,
+ .destroy = drm_plane_cleanup,
+};
+
+static const struct drm_crtc_helper_funcs corebootdrm_crtc_helper_funcs = {
+ DRM_SYSFB_CRTC_HELPER_FUNCS,
+};
+
+static const struct drm_crtc_funcs corebootdrm_crtc_funcs = {
+ DRM_SYSFB_CRTC_FUNCS,
+ .destroy = drm_crtc_cleanup,
+};
+
+static const struct drm_encoder_funcs corebootdrm_encoder_funcs = {
+ .destroy = drm_encoder_cleanup,
+};
+
+static const struct drm_connector_helper_funcs corebootdrm_connector_helper_funcs = {
+ DRM_SYSFB_CONNECTOR_HELPER_FUNCS,
+};
+
+static const struct drm_connector_funcs corebootdrm_connector_funcs = {
+ DRM_SYSFB_CONNECTOR_FUNCS,
+ .destroy = drm_connector_cleanup,
+};
+
+static const struct drm_mode_config_funcs corebootdrm_mode_config_funcs = {
+ DRM_SYSFB_MODE_CONFIG_FUNCS,
+};
+
+static int corebootdrm_mode_config_init(struct corebootdrm_device *cdev)
+{
+ struct drm_sysfb_device *sysfb = &cdev->sysfb;
+ struct drm_device *dev = &sysfb->dev;
+ const struct drm_format_info *format = sysfb->fb_format;
+ unsigned int width = sysfb->fb_mode.hdisplay;
+ unsigned int height = sysfb->fb_mode.vdisplay;
+ struct drm_plane *primary_plane;
+ struct drm_crtc *crtc;
+ struct drm_encoder *encoder;
+ struct drm_connector *connector;
+ size_t nformats;
+ int ret;
+
+ ret = drmm_mode_config_init(dev);
+ if (ret)
+ return ret;
+
+ dev->mode_config.min_width = width;
+ dev->mode_config.max_width = max_t(unsigned int, width, DRM_SHADOW_PLANE_MAX_WIDTH);
+ dev->mode_config.min_height = height;
+ dev->mode_config.max_height = max_t(unsigned int, height, DRM_SHADOW_PLANE_MAX_HEIGHT);
+ dev->mode_config.funcs = &corebootdrm_mode_config_funcs;
+ dev->mode_config.preferred_depth = format->depth;
+
+ /* Primary plane */
+
+ nformats = drm_sysfb_build_fourcc_list(dev, &format->format, 1,
+ cdev->formats, ARRAY_SIZE(cdev->formats));
+
+ primary_plane = &cdev->primary_plane;
+ ret = drm_universal_plane_init(dev, primary_plane, 0, &corebootdrm_primary_plane_funcs,
+ cdev->formats, nformats,
+ corebootdrm_primary_plane_format_modifiers,
+ DRM_PLANE_TYPE_PRIMARY, NULL);
+ if (ret)
+ return ret;
+ drm_plane_helper_add(primary_plane, &corebootdrm_primary_plane_helper_funcs);
+ drm_plane_enable_fb_damage_clips(primary_plane);
+
+ /* CRTC */
+
+ crtc = &cdev->crtc;
+ ret = drm_crtc_init_with_planes(dev, crtc, primary_plane, NULL,
+ &corebootdrm_crtc_funcs, NULL);
+ if (ret)
+ return ret;
+ drm_crtc_helper_add(crtc, &corebootdrm_crtc_helper_funcs);
+
+ /* Encoder */
+
+ encoder = &cdev->encoder;
+ ret = drm_encoder_init(dev, encoder, &corebootdrm_encoder_funcs,
+ DRM_MODE_ENCODER_NONE, NULL);
+ if (ret)
+ return ret;
+ encoder->possible_crtcs = drm_crtc_mask(crtc);
+
+ /* Connector */
+
+ connector = &cdev->connector;
+ ret = drm_connector_init(dev, connector, &corebootdrm_connector_funcs,
+ DRM_MODE_CONNECTOR_Unknown);
+ if (ret)
+ return ret;
+ drm_connector_helper_add(connector, &corebootdrm_connector_helper_funcs);
+ drm_connector_set_panel_orientation_with_quirk(connector,
+ DRM_MODE_PANEL_ORIENTATION_UNKNOWN,
+ width, height);
+
+ ret = drm_connector_attach_encoder(connector, encoder);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+/*
+ * DRM driver
+ */
+
+DEFINE_DRM_GEM_FOPS(corebootdrm_fops);
+
+static struct drm_driver corebootdrm_drm_driver = {
+ DRM_GEM_SHMEM_DRIVER_OPS,
+ DRM_FBDEV_SHMEM_DRIVER_OPS,
+ .name = DRIVER_NAME,
+ .desc = DRIVER_DESC,
+ .major = DRIVER_MAJOR,
+ .minor = DRIVER_MINOR,
+ .driver_features = DRIVER_ATOMIC | DRIVER_GEM | DRIVER_MODESET,
+ .fops = &corebootdrm_fops,
+};
+
+/*
+ * Coreboot driver
+ */
+
+static int corebootdrm_probe(struct platform_device *pdev)
+{
+ const struct lb_framebuffer *fb = dev_get_platdata(&pdev->dev);
+ struct corebootdrm_device *cdev;
+ struct drm_sysfb_device *sysfb;
+ struct drm_device *dev;
+ const struct drm_format_info *format;
+ int width, height, pitch;
+ resource_size_t size;
+ phys_addr_t address;
+ struct resource *res, *mem = NULL;
+ struct resource aperture;
+ void __iomem *screen_base;
+ int ret;
+
+ cdev = devm_drm_dev_alloc(&pdev->dev, &corebootdrm_drm_driver,
+ struct corebootdrm_device, sysfb.dev);
+ if (IS_ERR(cdev))
+ return PTR_ERR(cdev);
+ platform_set_drvdata(pdev, cdev);
+
+ sysfb = &cdev->sysfb;
+ dev = &sysfb->dev;
+
+ if (!fb) {
+ drm_err(dev, "coreboot framebuffer not found\n");
+ return -EINVAL;
+ } else if (!LB_FRAMEBUFFER_HAS_LFB(fb)) {
+ drm_err(dev, "coreboot framebuffer entry too small\n");
+ return -EINVAL;
+ }
+
+ /*
+ * Hardware settings
+ */
+
+ format = corebootdrm_get_format_fb(dev, fb);
+ if (!format)
+ return -EINVAL;
+ width = corebootdrm_get_width_fb(dev, fb);
+ if (width < 0)
+ return width;
+ height = corebootdrm_get_height_fb(dev, fb);
+ if (height < 0)
+ return height;
+ pitch = corebootdrm_get_pitch_fb(dev, format, width, fb);
+ if (pitch < 0)
+ return pitch;
+ size = corebootdrm_get_size_fb(dev, height, pitch, fb);
+ if (!size)
+ return -EINVAL;
+ address = corebootdrm_get_address_fb(dev, size, fb);
+ if (!address)
+ return -EINVAL;
+
+ sysfb->fb_mode = drm_sysfb_mode(width, height, 0, 0);
+ sysfb->fb_format = format;
+ sysfb->fb_pitch = pitch;
+
+ drm_dbg(dev, "display mode={" DRM_MODE_FMT "}\n", DRM_MODE_ARG(&sysfb->fb_mode));
+ drm_dbg(dev, "framebuffer format=%p4cc, size=%dx%d, pitch=%d byte\n",
+ &format->format, width, height, pitch);
+
+ /*
+ * Memory management
+ */
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ drm_err(dev, "memory resource not found\n");
+ return -EINVAL;
+ }
+
+ mem = devm_request_mem_region(&pdev->dev, res->start, resource_size(res),
+ dev->driver->name);
+ if (!mem) {
+ drm_warn(dev, "could not acquire memory resource at %pr\n", res);
+ /*
+ * We cannot make this fatal. Sometimes this comes from magic
+ * spaces our resource handlers simply don't know about. Use
+ * the memory resource as-is and try to map that instead.
+ */
+ mem = res;
+ }
+
+ drm_dbg(dev, "using memory resource at %pr\n", mem);
+
+ aperture = DEFINE_RES_MEM(address, size);
+ if (!resource_contains(mem, &aperture)) {
+ drm_err(dev, "framebuffer aperture at invalid memory range %pr\n", &aperture);
+ return -EINVAL;
+ }
+
+ ret = devm_aperture_acquire_for_platform_device(pdev, address, size);
+ if (ret) {
+ drm_err(dev, "could not acquire framebuffer aperture: %d\n", ret);
+ return ret;
+ }
+
+ screen_base = devm_ioremap_wc(&pdev->dev, address, size);
+ if (!screen_base)
+ return -ENOMEM;
+
+ iosys_map_set_vaddr_iomem(&sysfb->fb_addr, screen_base);
+
+ /*
+ * DRM mode setting and registration
+ */
+
+ ret = corebootdrm_mode_config_init(cdev);
+ if (ret)
+ return ret;
+
+ drm_mode_config_reset(dev);
+
+ ret = drm_dev_register(dev, 0);
+ if (ret)
+ return ret;
+
+ drm_client_setup(dev, sysfb->fb_format);
+
+ return 0;
+}
+
+static void corebootdrm_remove(struct platform_device *pdev)
+{
+ struct corebootdrm_device *cdev = platform_get_drvdata(pdev);
+ struct drm_device *dev = &cdev->sysfb.dev;
+
+ drm_dev_unplug(dev);
+}
+
+static struct platform_driver corebootdrm_platform_driver = {
+ .driver = {
+ .name = "coreboot-framebuffer",
+ },
+ .probe = corebootdrm_probe,
+ .remove = corebootdrm_remove,
+};
+
+module_platform_driver(corebootdrm_platform_driver);
+
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE("GPL");
projects / thirdparty / linux.git / commitdiff
