Hi,
These series tries to improve the bochs driver and update documentation based on my brief experience with the fb-helper API. Thank you Daniel and Gerd for your previous feedback and helpful suggestions.
Patch 2 was previously posted and is unmodified except for acked-by + rebase on drm-misc-next (9a09a42369a4a37a959c051d8e1a1f948c1529a4). Patch 1 is a trivial (build) fix that was missing last time.
Patch 3 converts from the legacy API to the modern drm_dev_register approach. This seems required for the "generic" fbdev API as suggested by Daniel, but as bochs does not implement the required "gem_prime_vmap" function, the conversion cannot be completed for now.
Patch 4 includes some documentation updates that would have helped me during qxl/bochs development and a warning that made me realize that "a virtual address and that can be mmap'ed" in the documentation referred to "gem_prime_vmap". It is to my best of understanding, so please correct me if I am wrong.
Side note: I originally tried to fix the unbind/remove crash in QXL and then turned to bochs as it seemed simpler to learn how to work on DRM drivers. Hopefully I manage to eventually figure out how to fix QXL. QXL is a bit strange, it advertises PRIME "support" but it only has stub functions (including a stub gem_prime_vmap).
After my recent patch ("qxl: fix null-pointer crash during suspend") qxl can suspend/resume in the normal situation, but doing anything (suspend or unload) after unbinding just fails (suspend then fails with "failed to wait on release 23 after spincount 301", unload triggers a use-after-free according to KASAN). On the other hand, bochs passes these tests:
# 1. s/r with unbound console modprobe bochs_drm echo 0 > /sys/class/vtconsole/vtcon1/bind rtcwake -s 1 -m mem # 2. s/r in normal sitation echo 1 > /sys/class/vtconsole/vtcon1/bind rtcwake -s 1 -m mem # 3. unload module (and s/r for good measure) echo 0 > /sys/class/vtconsole/vtcon1/bind rmmod bochs_drm rtcwake -s 1 -m mem
Kind regards, Peter
Peter Wu (4): bochs: use drm_fb_helper_set_suspend_unlocked in suspend/resume bochs: convert to drm_fb_helper_fbdev_setup/teardown bochs: convert to drm_dev_register drm/fb-helper: improve documentation and print warnings
drivers/gpu/drm/bochs/bochs.h | 21 ++------ drivers/gpu/drm/bochs/bochs_drv.c | 46 +++++++++++------ drivers/gpu/drm/bochs/bochs_fbdev.c | 79 +++++++---------------------- drivers/gpu/drm/bochs/bochs_hw.c | 2 +- drivers/gpu/drm/bochs/bochs_kms.c | 7 +-- drivers/gpu/drm/bochs/bochs_mm.c | 74 --------------------------- drivers/gpu/drm/drm_fb_helper.c | 25 ++++++--- 7 files changed, 73 insertions(+), 181 deletions(-)
The "initialized" member is going away. suspend/resume still works (even if bochsfb_create is forced to fail).
Signed-off-by: Peter Wu peter@lekensteyn.nl --- drivers/gpu/drm/bochs/bochs_drv.c | 12 ++---------- 1 file changed, 2 insertions(+), 10 deletions(-)
diff --git a/drivers/gpu/drm/bochs/bochs_drv.c b/drivers/gpu/drm/bochs/bochs_drv.c index c61b40c72b62..0e79d9acf89e 100644 --- a/drivers/gpu/drm/bochs/bochs_drv.c +++ b/drivers/gpu/drm/bochs/bochs_drv.c @@ -107,11 +107,7 @@ static int bochs_pm_suspend(struct device *dev)
drm_kms_helper_poll_disable(drm_dev);
- if (bochs->fb.initialized) { - console_lock(); - drm_fb_helper_set_suspend(&bochs->fb.helper, 1); - console_unlock(); - } + drm_fb_helper_set_suspend_unlocked(&bochs->fb.helper, 1);
return 0; } @@ -124,11 +120,7 @@ static int bochs_pm_resume(struct device *dev)
drm_helper_resume_force_mode(drm_dev);
- if (bochs->fb.initialized) { - console_lock(); - drm_fb_helper_set_suspend(&bochs->fb.helper, 0); - console_unlock(); - } + drm_fb_helper_set_suspend_unlocked(&bochs->fb.helper, 0);
drm_kms_helper_poll_enable(drm_dev); return 0;
Currently unloading bochs_drm (after unbinding the vtconsole) results in a warning about a leaked connector:
[drm:drm_mode_config_cleanup] *ERROR* connector Virtual-3 leaked!
While investigating a potential fix I noticed that a lot of open-coded functionality is already implemented elsewhere, so start converting it: bochs_fbdev_init -> drm_fb_helper_fbdev_setup: trivial (similar impl). bochs_fbdev_fini -> drm_fb_helper_fbdev_teardown: requires unembedding "struct drm_framebuffer" from "struct bochs_framebuffer".
Unembedding drm_framebuffer is made easy using drm_gem_fbdev_fb_create which can replace bochs_fbdev_destroy and custom routines in bochs_mm.c. For this to work, the GEM object is moved into "drm_framebuffer". After that, "bochs_framebuffer" is no longer needed and therefore removed.
Remove the unused "size" and "initialized" fields from fb, the latter is not necessary as drm_fb_helper_fbdev_teardown can be called even if bochsfb_create fails. This theory was tested by returning early and late (just before drm_gem_fbdev_fb_create). Both scenarios fail gracefully although the latter seems to leak the object from bochsfb_create_object (not a regression).
Guess on the reason for the encoder leak: drm_framebuffer_cleanup was previously used, but did not destroy much. drm_fb_helper_fbdev_teardown is now used and calls drm_framebuffer_remove which does a bit more work.
Tested with 'echo 0 > /sys/class/vtconsole/vtcon1/bind; rmmod bochs_drm' and also with Xorg + fbdev (startx -> xterm). The latter triggered a warning in ttm_bo_vm_open that existed before, see https://lkml.kernel.org/r/1464000533-13140-4-git-send-email-mstaudt@suse.de
Acked-by: Daniel Vetter daniel.vetter@ffwll.ch Signed-off-by: Peter Wu peter@lekensteyn.nl --- drivers/gpu/drm/bochs/bochs.h | 19 ++----- drivers/gpu/drm/bochs/bochs_fbdev.c | 79 +++++++---------------------- drivers/gpu/drm/bochs/bochs_kms.c | 7 +-- drivers/gpu/drm/bochs/bochs_mm.c | 74 --------------------------- 4 files changed, 22 insertions(+), 157 deletions(-)
diff --git a/drivers/gpu/drm/bochs/bochs.h b/drivers/gpu/drm/bochs/bochs.h index 375bf92cd04f..8514a84fbdbe 100644 --- a/drivers/gpu/drm/bochs/bochs.h +++ b/drivers/gpu/drm/bochs/bochs.h @@ -51,11 +51,6 @@ enum bochs_types { BOCHS_UNKNOWN, };
-struct bochs_framebuffer { - struct drm_framebuffer base; - struct drm_gem_object *obj; -}; - struct bochs_device { /* hw */ void __iomem *mmio; @@ -88,15 +83,11 @@ struct bochs_device {
/* fbdev */ struct { - struct bochs_framebuffer gfb; + struct drm_framebuffer *fb; struct drm_fb_helper helper; - int size; - bool initialized; } fb; };
-#define to_bochs_framebuffer(x) container_of(x, struct bochs_framebuffer, base) - struct bochs_bo { struct ttm_buffer_object bo; struct ttm_placement placement; @@ -148,15 +139,9 @@ int bochs_dumb_create(struct drm_file *file, struct drm_device *dev, int bochs_dumb_mmap_offset(struct drm_file *file, struct drm_device *dev, uint32_t handle, uint64_t *offset);
-int bochs_framebuffer_init(struct drm_device *dev, - struct bochs_framebuffer *gfb, - const struct drm_mode_fb_cmd2 *mode_cmd, - struct drm_gem_object *obj); int bochs_bo_pin(struct bochs_bo *bo, u32 pl_flag, u64 *gpu_addr); int bochs_bo_unpin(struct bochs_bo *bo);
-extern const struct drm_mode_config_funcs bochs_mode_funcs; - /* bochs_kms.c */ int bochs_kms_init(struct bochs_device *bochs); void bochs_kms_fini(struct bochs_device *bochs); @@ -164,3 +149,5 @@ void bochs_kms_fini(struct bochs_device *bochs); /* bochs_fbdev.c */ int bochs_fbdev_init(struct bochs_device *bochs); void bochs_fbdev_fini(struct bochs_device *bochs); + +extern const struct drm_mode_config_funcs bochs_mode_funcs; diff --git a/drivers/gpu/drm/bochs/bochs_fbdev.c b/drivers/gpu/drm/bochs/bochs_fbdev.c index 14eb8d0d5a00..8f4d6c052f7b 100644 --- a/drivers/gpu/drm/bochs/bochs_fbdev.c +++ b/drivers/gpu/drm/bochs/bochs_fbdev.c @@ -6,6 +6,7 @@ */
#include "bochs.h" +#include <drm/drm_gem_framebuffer_helper.h>
/* ---------------------------------------------------------------------- */
@@ -13,9 +14,7 @@ static int bochsfb_mmap(struct fb_info *info, struct vm_area_struct *vma) { struct drm_fb_helper *fb_helper = info->par; - struct bochs_device *bochs = - container_of(fb_helper, struct bochs_device, fb.helper); - struct bochs_bo *bo = gem_to_bochs_bo(bochs->fb.gfb.obj); + struct bochs_bo *bo = gem_to_bochs_bo(fb_helper->fb->obj[0]);
return ttm_fbdev_mmap(vma, &bo->bo); } @@ -101,19 +100,20 @@ static int bochsfb_create(struct drm_fb_helper *helper,
/* init fb device */ info = drm_fb_helper_alloc_fbi(helper); - if (IS_ERR(info)) + if (IS_ERR(info)) { + DRM_ERROR("Failed to allocate fbi: %ld\n", PTR_ERR(info)); return PTR_ERR(info); + }
info->par = &bochs->fb.helper;
- ret = bochs_framebuffer_init(bochs->dev, &bochs->fb.gfb, &mode_cmd, gobj); - if (ret) - return ret; - - bochs->fb.size = size; + fb = drm_gem_fbdev_fb_create(bochs->dev, sizes, 0, gobj, NULL); + if (IS_ERR(fb)) { + DRM_ERROR("Failed to create framebuffer: %ld\n", PTR_ERR(fb)); + return PTR_ERR(fb); + }
/* setup helper */ - fb = &bochs->fb.gfb.base; bochs->fb.helper.fb = fb;
strcpy(info->fix.id, "bochsdrmfb"); @@ -130,27 +130,6 @@ static int bochsfb_create(struct drm_fb_helper *helper, drm_vma_offset_remove(&bo->bo.bdev->vma_manager, &bo->bo.vma_node); info->fix.smem_start = 0; info->fix.smem_len = size; - - bochs->fb.initialized = true; - return 0; -} - -static int bochs_fbdev_destroy(struct bochs_device *bochs) -{ - struct bochs_framebuffer *gfb = &bochs->fb.gfb; - - DRM_DEBUG_DRIVER("\n"); - - drm_fb_helper_unregister_fbi(&bochs->fb.helper); - - if (gfb->obj) { - drm_gem_object_unreference_unlocked(gfb->obj); - gfb->obj = NULL; - } - - drm_framebuffer_unregister_private(&gfb->base); - drm_framebuffer_cleanup(&gfb->base); - return 0; }
@@ -158,41 +137,17 @@ static const struct drm_fb_helper_funcs bochs_fb_helper_funcs = { .fb_probe = bochsfb_create, };
+const struct drm_mode_config_funcs bochs_mode_funcs = { + .fb_create = drm_gem_fb_create, +}; + int bochs_fbdev_init(struct bochs_device *bochs) { - int ret; - - drm_fb_helper_prepare(bochs->dev, &bochs->fb.helper, - &bochs_fb_helper_funcs); - - ret = drm_fb_helper_init(bochs->dev, &bochs->fb.helper, 1); - if (ret) - return ret; - - ret = drm_fb_helper_single_add_all_connectors(&bochs->fb.helper); - if (ret) - goto fini; - - drm_helper_disable_unused_functions(bochs->dev); - - ret = drm_fb_helper_initial_config(&bochs->fb.helper, 32); - if (ret) - goto fini; - - return 0; - -fini: - drm_fb_helper_fini(&bochs->fb.helper); - return ret; + return drm_fb_helper_fbdev_setup(bochs->dev, &bochs->fb.helper, + &bochs_fb_helper_funcs, 32, 1); }
void bochs_fbdev_fini(struct bochs_device *bochs) { - if (bochs->fb.initialized) - bochs_fbdev_destroy(bochs); - - if (bochs->fb.helper.fbdev) - drm_fb_helper_fini(&bochs->fb.helper); - - bochs->fb.initialized = false; + drm_fb_helper_fbdev_teardown(bochs->dev); } diff --git a/drivers/gpu/drm/bochs/bochs_kms.c b/drivers/gpu/drm/bochs/bochs_kms.c index ca5a9afdd5cf..ea9a43d31bf1 100644 --- a/drivers/gpu/drm/bochs/bochs_kms.c +++ b/drivers/gpu/drm/bochs/bochs_kms.c @@ -35,14 +35,12 @@ static int bochs_crtc_mode_set_base(struct drm_crtc *crtc, int x, int y, { struct bochs_device *bochs = container_of(crtc, struct bochs_device, crtc); - struct bochs_framebuffer *bochs_fb; struct bochs_bo *bo; u64 gpu_addr = 0; int ret;
if (old_fb) { - bochs_fb = to_bochs_framebuffer(old_fb); - bo = gem_to_bochs_bo(bochs_fb->obj); + bo = gem_to_bochs_bo(old_fb->obj[0]); ret = ttm_bo_reserve(&bo->bo, true, false, NULL); if (ret) { DRM_ERROR("failed to reserve old_fb bo\n"); @@ -55,8 +53,7 @@ static int bochs_crtc_mode_set_base(struct drm_crtc *crtc, int x, int y, if (WARN_ON(crtc->primary->fb == NULL)) return -EINVAL;
- bochs_fb = to_bochs_framebuffer(crtc->primary->fb); - bo = gem_to_bochs_bo(bochs_fb->obj); + bo = gem_to_bochs_bo(crtc->primary->fb->obj[0]); ret = ttm_bo_reserve(&bo->bo, true, false, NULL); if (ret) return ret; diff --git a/drivers/gpu/drm/bochs/bochs_mm.c b/drivers/gpu/drm/bochs/bochs_mm.c index c9c7097030ca..a61c1ecb2bdc 100644 --- a/drivers/gpu/drm/bochs/bochs_mm.c +++ b/drivers/gpu/drm/bochs/bochs_mm.c @@ -457,77 +457,3 @@ int bochs_dumb_mmap_offset(struct drm_file *file, struct drm_device *dev, drm_gem_object_unreference_unlocked(obj); return 0; } - -/* ---------------------------------------------------------------------- */ - -static void bochs_user_framebuffer_destroy(struct drm_framebuffer *fb) -{ - struct bochs_framebuffer *bochs_fb = to_bochs_framebuffer(fb); - - drm_gem_object_unreference_unlocked(bochs_fb->obj); - drm_framebuffer_cleanup(fb); - kfree(fb); -} - -static const struct drm_framebuffer_funcs bochs_fb_funcs = { - .destroy = bochs_user_framebuffer_destroy, -}; - -int bochs_framebuffer_init(struct drm_device *dev, - struct bochs_framebuffer *gfb, - const struct drm_mode_fb_cmd2 *mode_cmd, - struct drm_gem_object *obj) -{ - int ret; - - drm_helper_mode_fill_fb_struct(dev, &gfb->base, mode_cmd); - gfb->obj = obj; - ret = drm_framebuffer_init(dev, &gfb->base, &bochs_fb_funcs); - if (ret) { - DRM_ERROR("drm_framebuffer_init failed: %d\n", ret); - return ret; - } - return 0; -} - -static struct drm_framebuffer * -bochs_user_framebuffer_create(struct drm_device *dev, - struct drm_file *filp, - const struct drm_mode_fb_cmd2 *mode_cmd) -{ - struct drm_gem_object *obj; - struct bochs_framebuffer *bochs_fb; - int ret; - - DRM_DEBUG_DRIVER("%dx%d, format %c%c%c%c\n", - mode_cmd->width, mode_cmd->height, - (mode_cmd->pixel_format) & 0xff, - (mode_cmd->pixel_format >> 8) & 0xff, - (mode_cmd->pixel_format >> 16) & 0xff, - (mode_cmd->pixel_format >> 24) & 0xff); - - if (mode_cmd->pixel_format != DRM_FORMAT_XRGB8888) - return ERR_PTR(-ENOENT); - - obj = drm_gem_object_lookup(filp, mode_cmd->handles[0]); - if (obj == NULL) - return ERR_PTR(-ENOENT); - - bochs_fb = kzalloc(sizeof(*bochs_fb), GFP_KERNEL); - if (!bochs_fb) { - drm_gem_object_unreference_unlocked(obj); - return ERR_PTR(-ENOMEM); - } - - ret = bochs_framebuffer_init(dev, bochs_fb, mode_cmd, obj); - if (ret) { - drm_gem_object_unreference_unlocked(obj); - kfree(bochs_fb); - return ERR_PTR(ret); - } - return &bochs_fb->base; -} - -const struct drm_mode_config_funcs bochs_mode_funcs = { - .fb_create = bochs_user_framebuffer_create, -};
The drm_get_pci_dev API is deprecated, replace it by drm_dev_register.
Signed-off-by: Peter Wu peter@lekensteyn.nl --- drivers/gpu/drm/bochs/bochs.h | 2 +- drivers/gpu/drm/bochs/bochs_drv.c | 34 +++++++++++++++++++++++++------ drivers/gpu/drm/bochs/bochs_hw.c | 2 +- 3 files changed, 30 insertions(+), 8 deletions(-)
diff --git a/drivers/gpu/drm/bochs/bochs.h b/drivers/gpu/drm/bochs/bochs.h index 8514a84fbdbe..b4f6bb521900 100644 --- a/drivers/gpu/drm/bochs/bochs.h +++ b/drivers/gpu/drm/bochs/bochs.h @@ -117,7 +117,7 @@ static inline u64 bochs_bo_mmap_offset(struct bochs_bo *bo) /* ---------------------------------------------------------------------- */
/* bochs_hw.c */ -int bochs_hw_init(struct drm_device *dev, uint32_t flags); +int bochs_hw_init(struct drm_device *dev); void bochs_hw_fini(struct drm_device *dev);
void bochs_hw_setmode(struct bochs_device *bochs, diff --git a/drivers/gpu/drm/bochs/bochs_drv.c b/drivers/gpu/drm/bochs/bochs_drv.c index 0e79d9acf89e..f3dd66ae990a 100644 --- a/drivers/gpu/drm/bochs/bochs_drv.c +++ b/drivers/gpu/drm/bochs/bochs_drv.c @@ -35,7 +35,7 @@ static void bochs_unload(struct drm_device *dev) dev->dev_private = NULL; }
-static int bochs_load(struct drm_device *dev, unsigned long flags) +static int bochs_load(struct drm_device *dev) { struct bochs_device *bochs; int ret; @@ -46,7 +46,7 @@ static int bochs_load(struct drm_device *dev, unsigned long flags) dev->dev_private = bochs; bochs->dev = dev;
- ret = bochs_hw_init(dev, flags); + ret = bochs_hw_init(dev); if (ret) goto err;
@@ -82,8 +82,6 @@ static const struct file_operations bochs_fops = {
static struct drm_driver bochs_driver = { .driver_features = DRIVER_GEM | DRIVER_MODESET, - .load = bochs_load, - .unload = bochs_unload, .fops = &bochs_fops, .name = "bochs-drm", .desc = "bochs dispi vga interface (qemu stdvga)", @@ -138,6 +136,7 @@ static const struct dev_pm_ops bochs_pm_ops = { static int bochs_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent) { + struct drm_device *dev; unsigned long fbsize; int ret;
@@ -151,14 +150,37 @@ static int bochs_pci_probe(struct pci_dev *pdev, if (ret) return ret;
- return drm_get_pci_dev(pdev, ent, &bochs_driver); + dev = drm_dev_alloc(&bochs_driver, &pdev->dev); + if (IS_ERR(dev)) + return PTR_ERR(dev); + + dev->pdev = pdev; + pci_set_drvdata(pdev, dev); + + ret = bochs_load(dev); + if (ret) + goto err_free_dev; + + ret = drm_dev_register(dev, 0); + if (ret) + goto err_unload; + + return ret; + +err_unload: + bochs_unload(dev); +err_free_dev: + drm_dev_put(dev); + return ret; }
static void bochs_pci_remove(struct pci_dev *pdev) { struct drm_device *dev = pci_get_drvdata(pdev);
- drm_put_dev(dev); + drm_dev_unregister(dev); + bochs_unload(dev); + drm_dev_put(dev); }
static const struct pci_device_id bochs_pci_tbl[] = { diff --git a/drivers/gpu/drm/bochs/bochs_hw.c b/drivers/gpu/drm/bochs/bochs_hw.c index a39b0343c197..16e4f1caccca 100644 --- a/drivers/gpu/drm/bochs/bochs_hw.c +++ b/drivers/gpu/drm/bochs/bochs_hw.c @@ -47,7 +47,7 @@ static void bochs_dispi_write(struct bochs_device *bochs, u16 reg, u16 val) } }
-int bochs_hw_init(struct drm_device *dev, uint32_t flags) +int bochs_hw_init(struct drm_device *dev) { struct bochs_device *bochs = dev->dev_private; struct pci_dev *pdev = dev->pdev;
Clarify the relation between drm_fb_helper_fbdev_setup/teardown. Clarify requirements for the new generic fbdev emulation API and log some more details in case the driver does something wrong. Fix related typos.
Cc: Noralf Trønnes noralf@tronnes.org Signed-off-by: Peter Wu peter@lekensteyn.nl --- drivers/gpu/drm/drm_fb_helper.c | 25 +++++++++++++++++++------ 1 file changed, 19 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c index 4b0dd20bccb8..7f92ff173986 100644 --- a/drivers/gpu/drm/drm_fb_helper.c +++ b/drivers/gpu/drm/drm_fb_helper.c @@ -2821,7 +2821,9 @@ EXPORT_SYMBOL(drm_fb_helper_hotplug_event); * The caller must to provide a &drm_fb_helper_funcs->fb_probe callback * function. * - * See also: drm_fb_helper_initial_config() + * Use drm_fb_helper_fbdev_teardown() to destroy the fbdev. + * + * See also: drm_fb_helper_initial_config(), drm_fbdev_generic_setup(). * * Returns: * Zero on success or negative error code on failure. @@ -3037,7 +3039,7 @@ static struct fb_deferred_io drm_fbdev_defio = { * @fb_helper: fbdev helper structure * @sizes: describes fbdev size and scanout surface size * - * This function uses the client API to crate a framebuffer backed by a dumb buffer. + * This function uses the client API to create a framebuffer backed by a dumb buffer. * * The _sys_ versions are used for &fb_ops.fb_read, fb_write, fb_fillrect, * fb_copyarea, fb_imageblit. @@ -3165,8 +3167,10 @@ static int drm_fbdev_client_hotplug(struct drm_client_dev *client) if (dev->fb_helper) return drm_fb_helper_hotplug_event(dev->fb_helper);
- if (!dev->mode_config.num_connector) + if (!dev->mode_config.num_connector) { + DRM_DEV_DEBUG(dev->dev, "No connectors found, will not create framebuffer!\n"); return 0; + }
ret = drm_fb_helper_fbdev_setup(dev, fb_helper, &drm_fb_helper_generic_funcs, fb_helper->preferred_bpp, 0); @@ -3187,13 +3191,15 @@ static const struct drm_client_funcs drm_fbdev_client_funcs = { };
/** - * drm_fb_helper_generic_fbdev_setup() - Setup generic fbdev emulation + * drm_fbdev_generic_setup() - Setup generic fbdev emulation * @dev: DRM device * @preferred_bpp: Preferred bits per pixel for the device. * @dev->mode_config.preferred_depth is used if this is zero. * * This function sets up generic fbdev emulation for drivers that supports - * dumb buffers with a virtual address and that can be mmap'ed. + * dumb buffers with a virtual address and that can be mmap'ed. If the driver + * does not support these functions, it could use drm_fb_helper_fbdev_setup(). + * This function can only be used with devices created using drm_dev_register(). * * Restore, hotplug events and teardown are all taken care of. Drivers that do * suspend/resume need to call drm_fb_helper_set_suspend_unlocked() themselves. @@ -3206,6 +3212,8 @@ static const struct drm_client_funcs drm_fbdev_client_funcs = { * This function is safe to call even when there are no connectors present. * Setup will be retried on the next hotplug event. * + * The fbdev is destroyed by drm_dev_unregister(). + * * Returns: * Zero on success or negative error code on failure. */ @@ -3214,6 +3222,8 @@ int drm_fbdev_generic_setup(struct drm_device *dev, unsigned int preferred_bpp) struct drm_fb_helper *fb_helper; int ret;
+ WARN(dev->fb_helper, "fb_helper is already set!\n"); + if (!drm_fbdev_emulation) return 0;
@@ -3224,12 +3234,15 @@ int drm_fbdev_generic_setup(struct drm_device *dev, unsigned int preferred_bpp) ret = drm_client_new(dev, &fb_helper->client, "fbdev", &drm_fbdev_client_funcs); if (ret) { kfree(fb_helper); + DRM_DEV_ERROR(dev->dev, "Failed to register client: %d\n", ret); return ret; }
fb_helper->preferred_bpp = preferred_bpp;
- drm_fbdev_client_hotplug(&fb_helper->client); + ret = drm_fbdev_client_hotplug(&fb_helper->client); + if (ret) + DRM_DEV_DEBUG(dev->dev, "client hotplug ret=%d\n", ret);
return 0; }
On Fri, Sep 07, 2018 at 12:18:10AM +0200, Peter Wu wrote:
Clarify the relation between drm_fb_helper_fbdev_setup/teardown. Clarify requirements for the new generic fbdev emulation API and log some more details in case the driver does something wrong. Fix related typos.
Cc: Noralf Trønnes noralf@tronnes.org Signed-off-by: Peter Wu peter@lekensteyn.nl
drivers/gpu/drm/drm_fb_helper.c | 25 +++++++++++++++++++------ 1 file changed, 19 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c index 4b0dd20bccb8..7f92ff173986 100644 --- a/drivers/gpu/drm/drm_fb_helper.c +++ b/drivers/gpu/drm/drm_fb_helper.c @@ -2821,7 +2821,9 @@ EXPORT_SYMBOL(drm_fb_helper_hotplug_event);
- The caller must to provide a &drm_fb_helper_funcs->fb_probe callback
- function.
- See also: drm_fb_helper_initial_config()
- Use drm_fb_helper_fbdev_teardown() to destroy the fbdev.
- See also: drm_fb_helper_initial_config(), drm_fbdev_generic_setup().
- Returns:
- Zero on success or negative error code on failure.
@@ -3037,7 +3039,7 @@ static struct fb_deferred_io drm_fbdev_defio = {
- @fb_helper: fbdev helper structure
- @sizes: describes fbdev size and scanout surface size
- This function uses the client API to crate a framebuffer backed by a dumb buffer.
- This function uses the client API to create a framebuffer backed by a dumb buffer.
- The _sys_ versions are used for &fb_ops.fb_read, fb_write, fb_fillrect,
- fb_copyarea, fb_imageblit.
@@ -3165,8 +3167,10 @@ static int drm_fbdev_client_hotplug(struct drm_client_dev *client) if (dev->fb_helper) return drm_fb_helper_hotplug_event(dev->fb_helper);
- if (!dev->mode_config.num_connector)
if (!dev->mode_config.num_connector) {
DRM_DEV_DEBUG(dev->dev, "No connectors found, will not create framebuffer!\n");
return 0;
}
ret = drm_fb_helper_fbdev_setup(dev, fb_helper, &drm_fb_helper_generic_funcs, fb_helper->preferred_bpp, 0);
@@ -3187,13 +3191,15 @@ static const struct drm_client_funcs drm_fbdev_client_funcs = { };
/**
- drm_fb_helper_generic_fbdev_setup() - Setup generic fbdev emulation
- drm_fbdev_generic_setup() - Setup generic fbdev emulation
Hm, drm_fb_helper_ would be the OCD prefix we use everywhere, but better to make the docs match the code. Feel free to throw a rename patch on top.
- @dev: DRM device
- @preferred_bpp: Preferred bits per pixel for the device.
@dev->mode_config.preferred_depth is used if this is zero.
- This function sets up generic fbdev emulation for drivers that supports
- dumb buffers with a virtual address and that can be mmap'ed.
- dumb buffers with a virtual address and that can be mmap'ed. If the driver
- does not support these functions, it could use drm_fb_helper_fbdev_setup().
- This function can only be used with devices created using drm_dev_register().
This last line is misleading, since every drm device is called with drm_dev_register(). It's just not all called by driver code directly. With this line removed:
Reviewed-by: Daniel Vetter daniel.vetter@ffwll.ch
I'll leave it to Gerd to apply this all. -Daniel
- Restore, hotplug events and teardown are all taken care of. Drivers that do
- suspend/resume need to call drm_fb_helper_set_suspend_unlocked() themselves.
@@ -3206,6 +3212,8 @@ static const struct drm_client_funcs drm_fbdev_client_funcs = {
- This function is safe to call even when there are no connectors present.
- Setup will be retried on the next hotplug event.
- The fbdev is destroyed by drm_dev_unregister().
*/
- Returns:
- Zero on success or negative error code on failure.
@@ -3214,6 +3222,8 @@ int drm_fbdev_generic_setup(struct drm_device *dev, unsigned int preferred_bpp) struct drm_fb_helper *fb_helper; int ret;
- WARN(dev->fb_helper, "fb_helper is already set!\n");
- if (!drm_fbdev_emulation) return 0;
@@ -3224,12 +3234,15 @@ int drm_fbdev_generic_setup(struct drm_device *dev, unsigned int preferred_bpp) ret = drm_client_new(dev, &fb_helper->client, "fbdev", &drm_fbdev_client_funcs); if (ret) { kfree(fb_helper);
DRM_DEV_ERROR(dev->dev, "Failed to register client: %d\n", ret);
return ret; }
fb_helper->preferred_bpp = preferred_bpp;
- drm_fbdev_client_hotplug(&fb_helper->client);
ret = drm_fbdev_client_hotplug(&fb_helper->client);
if (ret)
DRM_DEV_DEBUG(dev->dev, "client hotplug ret=%d\n", ret);
return 0;
}
2.18.0
dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel
- This function sets up generic fbdev emulation for drivers that supports
- dumb buffers with a virtual address and that can be mmap'ed.
- dumb buffers with a virtual address and that can be mmap'ed. If the driver
- does not support these functions, it could use drm_fb_helper_fbdev_setup().
- This function can only be used with devices created using drm_dev_register().
This last line is misleading, since every drm device is called with drm_dev_register(). It's just not all called by driver code directly. With this line removed:
Reviewed-by: Daniel Vetter daniel.vetter@ffwll.ch
I'll leave it to Gerd to apply this all.
Fixed and pushed.
cheers, Gerd
dri-devel@lists.freedesktop.org