| Message ID | 20201015123806.32416-11-tzimmermann@suse.de (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Support GEM object mappings from I/O memory | expand |
Hi Thomas. On Thu, Oct 15, 2020 at 02:38:06PM +0200, Thomas Zimmermann wrote: > At least sparc64 requires I/O-specific access to framebuffers. This > patch updates the fbdev console accordingly. > > For drivers with direct access to the framebuffer memory, the callback > functions in struct fb_ops test for the type of memory and call the rsp > fb_sys_ of fb_cfb_ functions. > > For drivers that employ a shadow buffer, fbdev's blit function retrieves > the framebuffer address as struct dma_buf_map, and uses dma_buf_map > interfaces to access the buffer. > > The bochs driver on sparc64 uses a workaround to flag the framebuffer as > I/O memory and avoid a HW exception. With the introduction of struct > dma_buf_map, this is not required any longer. The patch removes the rsp > code from both, bochs and fbdev. > > v4: > * move dma_buf_map changes into separate patch (Daniel) > * TODO list: comment on fbdev updates (Daniel) I have been offline for a while so have not followed all the threads on this. So may comments below may well be addressed but I failed to see it. If the point about fb_sync is already addressed/considered then: Reviewed-by: Sam Ravnborg <sam@ravnborg.org> > Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> > --- > Documentation/gpu/todo.rst | 19 ++- > drivers/gpu/drm/bochs/bochs_kms.c | 1 - > drivers/gpu/drm/drm_fb_helper.c | 217 ++++++++++++++++++++++++++++-- > include/drm/drm_mode_config.h | 12 -- > 4 files changed, 220 insertions(+), 29 deletions(-) > > diff --git a/Documentation/gpu/todo.rst b/Documentation/gpu/todo.rst > index 7e6fc3c04add..638b7f704339 100644 > --- a/Documentation/gpu/todo.rst > +++ b/Documentation/gpu/todo.rst > @@ -197,13 +197,28 @@ Convert drivers to use drm_fbdev_generic_setup() > ------------------------------------------------ > > Most drivers can use drm_fbdev_generic_setup(). Driver have to implement > -atomic modesetting and GEM vmap support. Current generic fbdev emulation > -expects the framebuffer in system memory (or system-like memory). > +atomic modesetting and GEM vmap support. Historically, generic fbdev emulation > +expected the framebuffer in system memory or system-like memory. By employing > +struct dma_buf_map, drivers with frambuffers in I/O memory can be supported > +as well. > > Contact: Maintainer of the driver you plan to convert > > Level: Intermediate > > +Reimplement functions in drm_fbdev_fb_ops without fbdev > +------------------------------------------------------- > + > +A number of callback functions in drm_fbdev_fb_ops could benefit from > +being rewritten without dependencies on the fbdev module. Some of the > +helpers could further benefit from using struct dma_buf_map instead of > +raw pointers. > + > +Contact: Thomas Zimmermann <tzimmermann@suse.de>, Daniel Vetter > + > +Level: Advanced > + > + > drm_framebuffer_funcs and drm_mode_config_funcs.fb_create cleanup > ----------------------------------------------------------------- > > diff --git a/drivers/gpu/drm/bochs/bochs_kms.c b/drivers/gpu/drm/bochs/bochs_kms.c > index 13d0d04c4457..853081d186d5 100644 > --- a/drivers/gpu/drm/bochs/bochs_kms.c > +++ b/drivers/gpu/drm/bochs/bochs_kms.c > @@ -151,7 +151,6 @@ int bochs_kms_init(struct bochs_device *bochs) > bochs->dev->mode_config.preferred_depth = 24; > bochs->dev->mode_config.prefer_shadow = 0; > bochs->dev->mode_config.prefer_shadow_fbdev = 1; > - bochs->dev->mode_config.fbdev_use_iomem = true; > bochs->dev->mode_config.quirk_addfb_prefer_host_byte_order = true; > > bochs->dev->mode_config.funcs = &bochs_mode_funcs; Good to see this workaround gone again! > diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c > index 6212cd7cde1d..462b0c130ebb 100644 > --- a/drivers/gpu/drm/drm_fb_helper.c > +++ b/drivers/gpu/drm/drm_fb_helper.c > @@ -372,24 +372,22 @@ static void drm_fb_helper_resume_worker(struct work_struct *work) > } > > static void drm_fb_helper_dirty_blit_real(struct drm_fb_helper *fb_helper, > - struct drm_clip_rect *clip) > + struct drm_clip_rect *clip, > + struct dma_buf_map *dst) > { > struct drm_framebuffer *fb = fb_helper->fb; > unsigned int cpp = fb->format->cpp[0]; > size_t offset = clip->y1 * fb->pitches[0] + clip->x1 * cpp; > void *src = fb_helper->fbdev->screen_buffer + offset; > - void *dst = fb_helper->buffer->map.vaddr + offset; > size_t len = (clip->x2 - clip->x1) * cpp; > unsigned int y; > > - for (y = clip->y1; y < clip->y2; y++) { > - if (!fb_helper->dev->mode_config.fbdev_use_iomem) > - memcpy(dst, src, len); > - else > - memcpy_toio((void __iomem *)dst, src, len); > + dma_buf_map_incr(dst, offset); /* go to first pixel within clip rect */ > > + for (y = clip->y1; y < clip->y2; y++) { > + dma_buf_map_memcpy_to(dst, src, len); > + dma_buf_map_incr(dst, fb->pitches[0]); > src += fb->pitches[0]; > - dst += fb->pitches[0]; > } > } > > @@ -417,8 +415,9 @@ static void drm_fb_helper_dirty_work(struct work_struct *work) > ret = drm_client_buffer_vmap(helper->buffer, &map); > if (ret) > return; > - drm_fb_helper_dirty_blit_real(helper, &clip_copy); > + drm_fb_helper_dirty_blit_real(helper, &clip_copy, &map); > } > + > if (helper->fb->funcs->dirty) > helper->fb->funcs->dirty(helper->fb, NULL, 0, 0, > &clip_copy, 1); > @@ -755,6 +754,136 @@ void drm_fb_helper_sys_imageblit(struct fb_info *info, > } > EXPORT_SYMBOL(drm_fb_helper_sys_imageblit); > So far everything looks good. > +static ssize_t drm_fb_helper_cfb_read(struct fb_info *info, char __user *buf, > + size_t count, loff_t *ppos) > +{ > + unsigned long p = *ppos; > + u8 *dst; > + u8 __iomem *src; > + int c, err = 0; > + unsigned long total_size; > + unsigned long alloc_size; > + ssize_t ret = 0; > + > + if (info->state != FBINFO_STATE_RUNNING) > + return -EPERM; > + > + total_size = info->screen_size; > + > + if (total_size == 0) > + total_size = info->fix.smem_len; > + > + if (p >= total_size) > + return 0; > + > + if (count >= total_size) > + count = total_size; > + > + if (count + p > total_size) > + count = total_size - p; > + > + src = (u8 __iomem *)(info->screen_base + p); screen_base is a char __iomem * - so this cast looks semi redundant. > + > + alloc_size = min(count, PAGE_SIZE); > + > + dst = kmalloc(alloc_size, GFP_KERNEL); > + if (!dst) > + return -ENOMEM; > + Same comment as below about fb_sync. > + while (count) { > + c = min(count, alloc_size); > + > + memcpy_fromio(dst, src, c); > + if (copy_to_user(buf, dst, c)) { > + err = -EFAULT; > + break; > + } > + > + src += c; > + *ppos += c; > + buf += c; > + ret += c; > + count -= c; > + } > + > + kfree(dst); > + > + if (err) > + return err; > + > + return ret; > +} > + > +static ssize_t drm_fb_helper_cfb_write(struct fb_info *info, const char __user *buf, > + size_t count, loff_t *ppos) > +{ > + unsigned long p = *ppos; > + u8 *src; > + u8 __iomem *dst; > + int c, err = 0; > + unsigned long total_size; > + unsigned long alloc_size; > + ssize_t ret = 0; > + > + if (info->state != FBINFO_STATE_RUNNING) > + return -EPERM; > + > + total_size = info->screen_size; > + > + if (total_size == 0) > + total_size = info->fix.smem_len; > + > + if (p > total_size) > + return -EFBIG; > + > + if (count > total_size) { > + err = -EFBIG; > + count = total_size; > + } > + > + if (count + p > total_size) { > + /* > + * The framebuffer is too small. We do the > + * copy operation, but return an error code > + * afterwards. Taken from fbdev. > + */ > + if (!err) > + err = -ENOSPC; > + count = total_size - p; > + } > + > + alloc_size = min(count, PAGE_SIZE); > + > + src = kmalloc(alloc_size, GFP_KERNEL); > + if (!src) > + return -ENOMEM; > + > + dst = (u8 __iomem *)(info->screen_base + p); > + The fbdev variant call the fb_sync callback here. noveau and gma500 implments the fb_sync callback - but no-one else. > + while (count) { > + c = min(count, alloc_size); > + > + if (copy_from_user(src, buf, c)) { > + err = -EFAULT; > + break; > + } > + memcpy_toio(dst, src, c); When we rewrite this part to use dma_buf_map_memcpy_to() then we can merge the two variants of helper_{sys,cfb}_read()? Which is part of the todo - so OK > + > + dst += c; > + *ppos += c; > + buf += c; > + ret += c; > + count -= c; > + } > + > + kfree(src); > + > + if (err) > + return err; > + > + return ret; > +} > + > /** > * drm_fb_helper_cfb_fillrect - wrapper around cfb_fillrect > * @info: fbdev registered by the helper > @@ -2027,6 +2156,66 @@ static int drm_fbdev_fb_mmap(struct fb_info *info, struct vm_area_struct *vma) > return -ENODEV; > } > > +static ssize_t drm_fbdev_fb_read(struct fb_info *info, char __user *buf, > + size_t count, loff_t *ppos) > +{ > + struct drm_fb_helper *fb_helper = info->par; > + struct drm_client_buffer *buffer = fb_helper->buffer; > + > + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) > + return drm_fb_helper_sys_read(info, buf, count, ppos); > + else > + return drm_fb_helper_cfb_read(info, buf, count, ppos); > +} > + > +static ssize_t drm_fbdev_fb_write(struct fb_info *info, const char __user *buf, > + size_t count, loff_t *ppos) > +{ > + struct drm_fb_helper *fb_helper = info->par; > + struct drm_client_buffer *buffer = fb_helper->buffer; > + > + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) > + return drm_fb_helper_sys_write(info, buf, count, ppos); > + else > + return drm_fb_helper_cfb_write(info, buf, count, ppos); > +} > + > +static void drm_fbdev_fb_fillrect(struct fb_info *info, > + const struct fb_fillrect *rect) > +{ > + struct drm_fb_helper *fb_helper = info->par; > + struct drm_client_buffer *buffer = fb_helper->buffer; > + > + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) > + drm_fb_helper_sys_fillrect(info, rect); > + else > + drm_fb_helper_cfb_fillrect(info, rect); > +} > + > +static void drm_fbdev_fb_copyarea(struct fb_info *info, > + const struct fb_copyarea *area) > +{ > + struct drm_fb_helper *fb_helper = info->par; > + struct drm_client_buffer *buffer = fb_helper->buffer; > + > + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) > + drm_fb_helper_sys_copyarea(info, area); > + else > + drm_fb_helper_cfb_copyarea(info, area); > +} > + > +static void drm_fbdev_fb_imageblit(struct fb_info *info, > + const struct fb_image *image) > +{ > + struct drm_fb_helper *fb_helper = info->par; > + struct drm_client_buffer *buffer = fb_helper->buffer; > + > + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) > + drm_fb_helper_sys_imageblit(info, image); > + else > + drm_fb_helper_cfb_imageblit(info, image); > +} > + > static const struct fb_ops drm_fbdev_fb_ops = { > .owner = THIS_MODULE, > DRM_FB_HELPER_DEFAULT_OPS, > @@ -2034,11 +2223,11 @@ static const struct fb_ops drm_fbdev_fb_ops = { > .fb_release = drm_fbdev_fb_release, > .fb_destroy = drm_fbdev_fb_destroy, > .fb_mmap = drm_fbdev_fb_mmap, > - .fb_read = drm_fb_helper_sys_read, > - .fb_write = drm_fb_helper_sys_write, > - .fb_fillrect = drm_fb_helper_sys_fillrect, > - .fb_copyarea = drm_fb_helper_sys_copyarea, > - .fb_imageblit = drm_fb_helper_sys_imageblit, > + .fb_read = drm_fbdev_fb_read, > + .fb_write = drm_fbdev_fb_write, > + .fb_fillrect = drm_fbdev_fb_fillrect, > + .fb_copyarea = drm_fbdev_fb_copyarea, > + .fb_imageblit = drm_fbdev_fb_imageblit, > }; > > static struct fb_deferred_io drm_fbdev_defio = { > diff --git a/include/drm/drm_mode_config.h b/include/drm/drm_mode_config.h > index 5ffbb4ed5b35..ab424ddd7665 100644 > --- a/include/drm/drm_mode_config.h > +++ b/include/drm/drm_mode_config.h > @@ -877,18 +877,6 @@ struct drm_mode_config { > */ > bool prefer_shadow_fbdev; > > - /** > - * @fbdev_use_iomem: > - * > - * Set to true if framebuffer reside in iomem. > - * When set to true memcpy_toio() is used when copying the framebuffer in > - * drm_fb_helper.drm_fb_helper_dirty_blit_real(). > - * > - * FIXME: This should be replaced with a per-mapping is_iomem > - * flag (like ttm does), and then used everywhere in fbdev code. > - */ > - bool fbdev_use_iomem; > - > /** > * @quirk_addfb_prefer_xbgr_30bpp: > * > -- > 2.28.0
Hi On Fri, 16 Oct 2020 12:58:54 +0200 Sam Ravnborg <sam@ravnborg.org> wrote: > Hi Thomas. > > On Thu, Oct 15, 2020 at 02:38:06PM +0200, Thomas Zimmermann wrote: > > At least sparc64 requires I/O-specific access to framebuffers. This > > patch updates the fbdev console accordingly. > > > > For drivers with direct access to the framebuffer memory, the callback > > functions in struct fb_ops test for the type of memory and call the rsp > > fb_sys_ of fb_cfb_ functions. > > > > For drivers that employ a shadow buffer, fbdev's blit function retrieves > > the framebuffer address as struct dma_buf_map, and uses dma_buf_map > > interfaces to access the buffer. > > > > The bochs driver on sparc64 uses a workaround to flag the framebuffer as > > I/O memory and avoid a HW exception. With the introduction of struct > > dma_buf_map, this is not required any longer. The patch removes the rsp > > code from both, bochs and fbdev. > > > > v4: > > * move dma_buf_map changes into separate patch (Daniel) > > * TODO list: comment on fbdev updates (Daniel) > > I have been offline for a while so have not followed all the threads on > this. So may comments below may well be addressed but I failed to see > it. > > If the point about fb_sync is already addressed/considered then: > Reviewed-by: Sam Ravnborg <sam@ravnborg.org> It has not been brought up yet. See below. > > > > Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> > > --- > > Documentation/gpu/todo.rst | 19 ++- > > drivers/gpu/drm/bochs/bochs_kms.c | 1 - > > drivers/gpu/drm/drm_fb_helper.c | 217 ++++++++++++++++++++++++++++-- > > include/drm/drm_mode_config.h | 12 -- > > 4 files changed, 220 insertions(+), 29 deletions(-) > > > > diff --git a/Documentation/gpu/todo.rst b/Documentation/gpu/todo.rst > > index 7e6fc3c04add..638b7f704339 100644 > > --- a/Documentation/gpu/todo.rst > > +++ b/Documentation/gpu/todo.rst > > @@ -197,13 +197,28 @@ Convert drivers to use drm_fbdev_generic_setup() > > ------------------------------------------------ > > > > Most drivers can use drm_fbdev_generic_setup(). Driver have to implement > > -atomic modesetting and GEM vmap support. Current generic fbdev emulation > > -expects the framebuffer in system memory (or system-like memory). > > +atomic modesetting and GEM vmap support. Historically, generic fbdev > > emulation +expected the framebuffer in system memory or system-like > > memory. By employing +struct dma_buf_map, drivers with frambuffers in I/O > > memory can be supported +as well. > > > > Contact: Maintainer of the driver you plan to convert > > > > Level: Intermediate > > > > +Reimplement functions in drm_fbdev_fb_ops without fbdev > > +------------------------------------------------------- > > + > > +A number of callback functions in drm_fbdev_fb_ops could benefit from > > +being rewritten without dependencies on the fbdev module. Some of the > > +helpers could further benefit from using struct dma_buf_map instead of > > +raw pointers. > > + > > +Contact: Thomas Zimmermann <tzimmermann@suse.de>, Daniel Vetter > > + > > +Level: Advanced > > + > > + > > drm_framebuffer_funcs and drm_mode_config_funcs.fb_create cleanup > > ----------------------------------------------------------------- > > > > diff --git a/drivers/gpu/drm/bochs/bochs_kms.c > > b/drivers/gpu/drm/bochs/bochs_kms.c index 13d0d04c4457..853081d186d5 > > 100644 --- a/drivers/gpu/drm/bochs/bochs_kms.c > > +++ b/drivers/gpu/drm/bochs/bochs_kms.c > > @@ -151,7 +151,6 @@ int bochs_kms_init(struct bochs_device *bochs) > > bochs->dev->mode_config.preferred_depth = 24; > > bochs->dev->mode_config.prefer_shadow = 0; > > bochs->dev->mode_config.prefer_shadow_fbdev = 1; > > - bochs->dev->mode_config.fbdev_use_iomem = true; > > bochs->dev->mode_config.quirk_addfb_prefer_host_byte_order = > > true; > > bochs->dev->mode_config.funcs = &bochs_mode_funcs; > Good to see this workaround gone again! > > > diff --git a/drivers/gpu/drm/drm_fb_helper.c > > b/drivers/gpu/drm/drm_fb_helper.c index 6212cd7cde1d..462b0c130ebb 100644 > > --- a/drivers/gpu/drm/drm_fb_helper.c > > +++ b/drivers/gpu/drm/drm_fb_helper.c > > @@ -372,24 +372,22 @@ static void drm_fb_helper_resume_worker(struct > > work_struct *work) } > > > > static void drm_fb_helper_dirty_blit_real(struct drm_fb_helper > > *fb_helper, > > - struct drm_clip_rect *clip) > > + struct drm_clip_rect *clip, > > + struct dma_buf_map *dst) > > { > > struct drm_framebuffer *fb = fb_helper->fb; > > unsigned int cpp = fb->format->cpp[0]; > > size_t offset = clip->y1 * fb->pitches[0] + clip->x1 * cpp; > > void *src = fb_helper->fbdev->screen_buffer + offset; > > - void *dst = fb_helper->buffer->map.vaddr + offset; > > size_t len = (clip->x2 - clip->x1) * cpp; > > unsigned int y; > > > > - for (y = clip->y1; y < clip->y2; y++) { > > - if (!fb_helper->dev->mode_config.fbdev_use_iomem) > > - memcpy(dst, src, len); > > - else > > - memcpy_toio((void __iomem *)dst, src, len); > > + dma_buf_map_incr(dst, offset); /* go to first pixel within clip > > rect */ > > + for (y = clip->y1; y < clip->y2; y++) { > > + dma_buf_map_memcpy_to(dst, src, len); > > + dma_buf_map_incr(dst, fb->pitches[0]); > > src += fb->pitches[0]; > > - dst += fb->pitches[0]; > > } > > } > > > > @@ -417,8 +415,9 @@ static void drm_fb_helper_dirty_work(struct > > work_struct *work) ret = drm_client_buffer_vmap(helper->buffer, &map); > > if (ret) > > return; > > - drm_fb_helper_dirty_blit_real(helper, > > &clip_copy); > > + drm_fb_helper_dirty_blit_real(helper, > > &clip_copy, &map); } > > + > > if (helper->fb->funcs->dirty) > > helper->fb->funcs->dirty(helper->fb, NULL, 0, 0, > > &clip_copy, 1); > > @@ -755,6 +754,136 @@ void drm_fb_helper_sys_imageblit(struct fb_info > > *info, } > > EXPORT_SYMBOL(drm_fb_helper_sys_imageblit); > > > So far everything looks good. > > > +static ssize_t drm_fb_helper_cfb_read(struct fb_info *info, char __user > > *buf, > > + size_t count, loff_t *ppos) > > +{ > > + unsigned long p = *ppos; > > + u8 *dst; > > + u8 __iomem *src; > > + int c, err = 0; > > + unsigned long total_size; > > + unsigned long alloc_size; > > + ssize_t ret = 0; > > + > > + if (info->state != FBINFO_STATE_RUNNING) > > + return -EPERM; > > + > > + total_size = info->screen_size; > > + > > + if (total_size == 0) > > + total_size = info->fix.smem_len; > > + > > + if (p >= total_size) > > + return 0; > > + > > + if (count >= total_size) > > + count = total_size; > > + > > + if (count + p > total_size) > > + count = total_size - p; > > + > > + src = (u8 __iomem *)(info->screen_base + p); > screen_base is a char __iomem * - so this cast looks semi redundant. I took the basic code from fbdev. Maybe there's a reason for the case, otherwise I'll remove it. > > > + > > + alloc_size = min(count, PAGE_SIZE); > > + > > + dst = kmalloc(alloc_size, GFP_KERNEL); > > + if (!dst) > > + return -ENOMEM; > > + > Same comment as below about fb_sync. > > > > + while (count) { > > + c = min(count, alloc_size); > > + > > + memcpy_fromio(dst, src, c); > > + if (copy_to_user(buf, dst, c)) { > > + err = -EFAULT; > > + break; > > + } > > + > > + src += c; > > + *ppos += c; > > + buf += c; > > + ret += c; > > + count -= c; > > + } > > + > > + kfree(dst); > > + > > + if (err) > > + return err; > > + > > + return ret; > > +} > > + > > +static ssize_t drm_fb_helper_cfb_write(struct fb_info *info, const char > > __user *buf, > > + size_t count, loff_t *ppos) > > +{ > > + unsigned long p = *ppos; > > + u8 *src; > > + u8 __iomem *dst; > > + int c, err = 0; > > + unsigned long total_size; > > + unsigned long alloc_size; > > + ssize_t ret = 0; > > + > > + if (info->state != FBINFO_STATE_RUNNING) > > + return -EPERM; > > + > > + total_size = info->screen_size; > > + > > + if (total_size == 0) > > + total_size = info->fix.smem_len; > > + > > + if (p > total_size) > > + return -EFBIG; > > + > > + if (count > total_size) { > > + err = -EFBIG; > > + count = total_size; > > + } > > + > > + if (count + p > total_size) { > > + /* > > + * The framebuffer is too small. We do the > > + * copy operation, but return an error code > > + * afterwards. Taken from fbdev. > > + */ > > + if (!err) > > + err = -ENOSPC; > > + count = total_size - p; > > + } > > + > > + alloc_size = min(count, PAGE_SIZE); > > + > > + src = kmalloc(alloc_size, GFP_KERNEL); > > + if (!src) > > + return -ENOMEM; > > + > > + dst = (u8 __iomem *)(info->screen_base + p); > > + > > The fbdev variant call the fb_sync callback here. > noveau and gma500 implments the fb_sync callback - but no-one else. These drivers implement some form of HW acceleration. If they have a HW blit/draw/etc op queued up, they have to wait for it to complete. Otherwise, the copied memory would contain an old state. The fb_sync acts as the fence. Fbdev only uses software copying, so the fb_sync is not required. From what I heard, the HW acceleration is not useful on modern machines. I hope to convert more drivers to generic fbdev after these patches for I/O-memory support have been merged. > > > > + while (count) { > > + c = min(count, alloc_size); > > + > > + if (copy_from_user(src, buf, c)) { > > + err = -EFAULT; > > + break; > > + } > > + memcpy_toio(dst, src, c); > When we rewrite this part to use dma_buf_map_memcpy_to() then we can > merge the two variants of helper_{sys,cfb}_read()? > Which is part of the todo - so OK I'm not sure if dma_buf_map is a good fit here. The I/O-memory function does an additional copy between system memory and I/O memory. Of course, the top and bottom of both functions are similar and could probably be shared. Best regards Thomas > > + > > + dst += c; > > + *ppos += c; > > + buf += c; > > + ret += c; > > + count -= c; > > + } > > + > > + kfree(src); > > + > > + if (err) > > + return err; > > + > > + return ret; > > +} > > + > > /** > > * drm_fb_helper_cfb_fillrect - wrapper around cfb_fillrect > > * @info: fbdev registered by the helper > > @@ -2027,6 +2156,66 @@ static int drm_fbdev_fb_mmap(struct fb_info *info, > > struct vm_area_struct *vma) return -ENODEV; > > } > > > > +static ssize_t drm_fbdev_fb_read(struct fb_info *info, char __user *buf, > > + size_t count, loff_t *ppos) > > +{ > > + struct drm_fb_helper *fb_helper = info->par; > > + struct drm_client_buffer *buffer = fb_helper->buffer; > > + > > + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) > > + return drm_fb_helper_sys_read(info, buf, count, ppos); > > + else > > + return drm_fb_helper_cfb_read(info, buf, count, ppos); > > +} > > + > > +static ssize_t drm_fbdev_fb_write(struct fb_info *info, const char > > __user *buf, > > + size_t count, loff_t *ppos) > > +{ > > + struct drm_fb_helper *fb_helper = info->par; > > + struct drm_client_buffer *buffer = fb_helper->buffer; > > + > > + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) > > + return drm_fb_helper_sys_write(info, buf, count, ppos); > > + else > > + return drm_fb_helper_cfb_write(info, buf, count, ppos); > > +} > > + > > +static void drm_fbdev_fb_fillrect(struct fb_info *info, > > + const struct fb_fillrect *rect) > > +{ > > + struct drm_fb_helper *fb_helper = info->par; > > + struct drm_client_buffer *buffer = fb_helper->buffer; > > + > > + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) > > + drm_fb_helper_sys_fillrect(info, rect); > > + else > > + drm_fb_helper_cfb_fillrect(info, rect); > > +} > > + > > +static void drm_fbdev_fb_copyarea(struct fb_info *info, > > + const struct fb_copyarea *area) > > +{ > > + struct drm_fb_helper *fb_helper = info->par; > > + struct drm_client_buffer *buffer = fb_helper->buffer; > > + > > + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) > > + drm_fb_helper_sys_copyarea(info, area); > > + else > > + drm_fb_helper_cfb_copyarea(info, area); > > +} > > + > > +static void drm_fbdev_fb_imageblit(struct fb_info *info, > > + const struct fb_image *image) > > +{ > > + struct drm_fb_helper *fb_helper = info->par; > > + struct drm_client_buffer *buffer = fb_helper->buffer; > > + > > + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) > > + drm_fb_helper_sys_imageblit(info, image); > > + else > > + drm_fb_helper_cfb_imageblit(info, image); > > +} > > + > > static const struct fb_ops drm_fbdev_fb_ops = { > > .owner = THIS_MODULE, > > DRM_FB_HELPER_DEFAULT_OPS, > > @@ -2034,11 +2223,11 @@ static const struct fb_ops drm_fbdev_fb_ops = { > > .fb_release = drm_fbdev_fb_release, > > .fb_destroy = drm_fbdev_fb_destroy, > > .fb_mmap = drm_fbdev_fb_mmap, > > - .fb_read = drm_fb_helper_sys_read, > > - .fb_write = drm_fb_helper_sys_write, > > - .fb_fillrect = drm_fb_helper_sys_fillrect, > > - .fb_copyarea = drm_fb_helper_sys_copyarea, > > - .fb_imageblit = drm_fb_helper_sys_imageblit, > > + .fb_read = drm_fbdev_fb_read, > > + .fb_write = drm_fbdev_fb_write, > > + .fb_fillrect = drm_fbdev_fb_fillrect, > > + .fb_copyarea = drm_fbdev_fb_copyarea, > > + .fb_imageblit = drm_fbdev_fb_imageblit, > > }; > > > > static struct fb_deferred_io drm_fbdev_defio = { > > diff --git a/include/drm/drm_mode_config.h b/include/drm/drm_mode_config.h > > index 5ffbb4ed5b35..ab424ddd7665 100644 > > --- a/include/drm/drm_mode_config.h > > +++ b/include/drm/drm_mode_config.h > > @@ -877,18 +877,6 @@ struct drm_mode_config { > > */ > > bool prefer_shadow_fbdev; > > > > - /** > > - * @fbdev_use_iomem: > > - * > > - * Set to true if framebuffer reside in iomem. > > - * When set to true memcpy_toio() is used when copying the > > framebuffer in > > - * drm_fb_helper.drm_fb_helper_dirty_blit_real(). > > - * > > - * FIXME: This should be replaced with a per-mapping is_iomem > > - * flag (like ttm does), and then used everywhere in fbdev code. > > - */ > > - bool fbdev_use_iomem; > > - > > /** > > * @quirk_addfb_prefer_xbgr_30bpp: > > * > > -- > > 2.28.0 > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel
Hi Thomas. On Thu, Oct 15, 2020 at 02:38:06PM +0200, Thomas Zimmermann wrote: > At least sparc64 requires I/O-specific access to framebuffers. This > patch updates the fbdev console accordingly. > > For drivers with direct access to the framebuffer memory, the callback > functions in struct fb_ops test for the type of memory and call the rsp > fb_sys_ of fb_cfb_ functions. > > For drivers that employ a shadow buffer, fbdev's blit function retrieves > the framebuffer address as struct dma_buf_map, and uses dma_buf_map > interfaces to access the buffer. > > The bochs driver on sparc64 uses a workaround to flag the framebuffer as > I/O memory and avoid a HW exception. With the introduction of struct > dma_buf_map, this is not required any longer. The patch removes the rsp > code from both, bochs and fbdev. > > v4: > * move dma_buf_map changes into separate patch (Daniel) > * TODO list: comment on fbdev updates (Daniel) > > Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> The original workaround fixed it so we could run qemu with the -nographic option. So I went ahead and tried to run quemu version: v5.0.0-1970-g0b100c8e72-dirty. And with the BOCHS driver built-in. With the following command line: qemu-system-sparc64 -m 512 -kernel vmlinux -append console=ttyS0 -nographic Behaviour was the same before and after applying this patch. (panic due to VFS: Unable to mount root fs on unknown-block(0,0)) So I consider it fixed for real now and not just a workaround. I also tested with: qemu-system-sparc64 -m 512 -kernel vmlinux -append console=ttyS0 -serial stdio and it worked in both cases too. All the comments above so future-me have an easier time finding how to reproduce. Tested-by: Sam Ravnborg <sam@ravnborg.org> Sam > --- > Documentation/gpu/todo.rst | 19 ++- > drivers/gpu/drm/bochs/bochs_kms.c | 1 - > drivers/gpu/drm/drm_fb_helper.c | 217 ++++++++++++++++++++++++++++-- > include/drm/drm_mode_config.h | 12 -- > 4 files changed, 220 insertions(+), 29 deletions(-) > > diff --git a/Documentation/gpu/todo.rst b/Documentation/gpu/todo.rst > index 7e6fc3c04add..638b7f704339 100644 > --- a/Documentation/gpu/todo.rst > +++ b/Documentation/gpu/todo.rst > @@ -197,13 +197,28 @@ Convert drivers to use drm_fbdev_generic_setup() > ------------------------------------------------ > > Most drivers can use drm_fbdev_generic_setup(). Driver have to implement > -atomic modesetting and GEM vmap support. Current generic fbdev emulation > -expects the framebuffer in system memory (or system-like memory). > +atomic modesetting and GEM vmap support. Historically, generic fbdev emulation > +expected the framebuffer in system memory or system-like memory. By employing > +struct dma_buf_map, drivers with frambuffers in I/O memory can be supported > +as well. > > Contact: Maintainer of the driver you plan to convert > > Level: Intermediate > > +Reimplement functions in drm_fbdev_fb_ops without fbdev > +------------------------------------------------------- > + > +A number of callback functions in drm_fbdev_fb_ops could benefit from > +being rewritten without dependencies on the fbdev module. Some of the > +helpers could further benefit from using struct dma_buf_map instead of > +raw pointers. > + > +Contact: Thomas Zimmermann <tzimmermann@suse.de>, Daniel Vetter > + > +Level: Advanced > + > + > drm_framebuffer_funcs and drm_mode_config_funcs.fb_create cleanup > ----------------------------------------------------------------- > > diff --git a/drivers/gpu/drm/bochs/bochs_kms.c b/drivers/gpu/drm/bochs/bochs_kms.c > index 13d0d04c4457..853081d186d5 100644 > --- a/drivers/gpu/drm/bochs/bochs_kms.c > +++ b/drivers/gpu/drm/bochs/bochs_kms.c > @@ -151,7 +151,6 @@ int bochs_kms_init(struct bochs_device *bochs) > bochs->dev->mode_config.preferred_depth = 24; > bochs->dev->mode_config.prefer_shadow = 0; > bochs->dev->mode_config.prefer_shadow_fbdev = 1; > - bochs->dev->mode_config.fbdev_use_iomem = true; > bochs->dev->mode_config.quirk_addfb_prefer_host_byte_order = true; > > bochs->dev->mode_config.funcs = &bochs_mode_funcs; > diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c > index 6212cd7cde1d..462b0c130ebb 100644 > --- a/drivers/gpu/drm/drm_fb_helper.c > +++ b/drivers/gpu/drm/drm_fb_helper.c > @@ -372,24 +372,22 @@ static void drm_fb_helper_resume_worker(struct work_struct *work) > } > > static void drm_fb_helper_dirty_blit_real(struct drm_fb_helper *fb_helper, > - struct drm_clip_rect *clip) > + struct drm_clip_rect *clip, > + struct dma_buf_map *dst) > { > struct drm_framebuffer *fb = fb_helper->fb; > unsigned int cpp = fb->format->cpp[0]; > size_t offset = clip->y1 * fb->pitches[0] + clip->x1 * cpp; > void *src = fb_helper->fbdev->screen_buffer + offset; > - void *dst = fb_helper->buffer->map.vaddr + offset; > size_t len = (clip->x2 - clip->x1) * cpp; > unsigned int y; > > - for (y = clip->y1; y < clip->y2; y++) { > - if (!fb_helper->dev->mode_config.fbdev_use_iomem) > - memcpy(dst, src, len); > - else > - memcpy_toio((void __iomem *)dst, src, len); > + dma_buf_map_incr(dst, offset); /* go to first pixel within clip rect */ > > + for (y = clip->y1; y < clip->y2; y++) { > + dma_buf_map_memcpy_to(dst, src, len); > + dma_buf_map_incr(dst, fb->pitches[0]); > src += fb->pitches[0]; > - dst += fb->pitches[0]; > } > } > > @@ -417,8 +415,9 @@ static void drm_fb_helper_dirty_work(struct work_struct *work) > ret = drm_client_buffer_vmap(helper->buffer, &map); > if (ret) > return; > - drm_fb_helper_dirty_blit_real(helper, &clip_copy); > + drm_fb_helper_dirty_blit_real(helper, &clip_copy, &map); > } > + > if (helper->fb->funcs->dirty) > helper->fb->funcs->dirty(helper->fb, NULL, 0, 0, > &clip_copy, 1); > @@ -755,6 +754,136 @@ void drm_fb_helper_sys_imageblit(struct fb_info *info, > } > EXPORT_SYMBOL(drm_fb_helper_sys_imageblit); > > +static ssize_t drm_fb_helper_cfb_read(struct fb_info *info, char __user *buf, > + size_t count, loff_t *ppos) > +{ > + unsigned long p = *ppos; > + u8 *dst; > + u8 __iomem *src; > + int c, err = 0; > + unsigned long total_size; > + unsigned long alloc_size; > + ssize_t ret = 0; > + > + if (info->state != FBINFO_STATE_RUNNING) > + return -EPERM; > + > + total_size = info->screen_size; > + > + if (total_size == 0) > + total_size = info->fix.smem_len; > + > + if (p >= total_size) > + return 0; > + > + if (count >= total_size) > + count = total_size; > + > + if (count + p > total_size) > + count = total_size - p; > + > + src = (u8 __iomem *)(info->screen_base + p); > + > + alloc_size = min(count, PAGE_SIZE); > + > + dst = kmalloc(alloc_size, GFP_KERNEL); > + if (!dst) > + return -ENOMEM; > + > + while (count) { > + c = min(count, alloc_size); > + > + memcpy_fromio(dst, src, c); > + if (copy_to_user(buf, dst, c)) { > + err = -EFAULT; > + break; > + } > + > + src += c; > + *ppos += c; > + buf += c; > + ret += c; > + count -= c; > + } > + > + kfree(dst); > + > + if (err) > + return err; > + > + return ret; > +} > + > +static ssize_t drm_fb_helper_cfb_write(struct fb_info *info, const char __user *buf, > + size_t count, loff_t *ppos) > +{ > + unsigned long p = *ppos; > + u8 *src; > + u8 __iomem *dst; > + int c, err = 0; > + unsigned long total_size; > + unsigned long alloc_size; > + ssize_t ret = 0; > + > + if (info->state != FBINFO_STATE_RUNNING) > + return -EPERM; > + > + total_size = info->screen_size; > + > + if (total_size == 0) > + total_size = info->fix.smem_len; > + > + if (p > total_size) > + return -EFBIG; > + > + if (count > total_size) { > + err = -EFBIG; > + count = total_size; > + } > + > + if (count + p > total_size) { > + /* > + * The framebuffer is too small. We do the > + * copy operation, but return an error code > + * afterwards. Taken from fbdev. > + */ > + if (!err) > + err = -ENOSPC; > + count = total_size - p; > + } > + > + alloc_size = min(count, PAGE_SIZE); > + > + src = kmalloc(alloc_size, GFP_KERNEL); > + if (!src) > + return -ENOMEM; > + > + dst = (u8 __iomem *)(info->screen_base + p); > + > + while (count) { > + c = min(count, alloc_size); > + > + if (copy_from_user(src, buf, c)) { > + err = -EFAULT; > + break; > + } > + memcpy_toio(dst, src, c); > + > + dst += c; > + *ppos += c; > + buf += c; > + ret += c; > + count -= c; > + } > + > + kfree(src); > + > + if (err) > + return err; > + > + return ret; > +} > + > /** > * drm_fb_helper_cfb_fillrect - wrapper around cfb_fillrect > * @info: fbdev registered by the helper > @@ -2027,6 +2156,66 @@ static int drm_fbdev_fb_mmap(struct fb_info *info, struct vm_area_struct *vma) > return -ENODEV; > } > > +static ssize_t drm_fbdev_fb_read(struct fb_info *info, char __user *buf, > + size_t count, loff_t *ppos) > +{ > + struct drm_fb_helper *fb_helper = info->par; > + struct drm_client_buffer *buffer = fb_helper->buffer; > + > + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) > + return drm_fb_helper_sys_read(info, buf, count, ppos); > + else > + return drm_fb_helper_cfb_read(info, buf, count, ppos); > +} > + > +static ssize_t drm_fbdev_fb_write(struct fb_info *info, const char __user *buf, > + size_t count, loff_t *ppos) > +{ > + struct drm_fb_helper *fb_helper = info->par; > + struct drm_client_buffer *buffer = fb_helper->buffer; > + > + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) > + return drm_fb_helper_sys_write(info, buf, count, ppos); > + else > + return drm_fb_helper_cfb_write(info, buf, count, ppos); > +} > + > +static void drm_fbdev_fb_fillrect(struct fb_info *info, > + const struct fb_fillrect *rect) > +{ > + struct drm_fb_helper *fb_helper = info->par; > + struct drm_client_buffer *buffer = fb_helper->buffer; > + > + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) > + drm_fb_helper_sys_fillrect(info, rect); > + else > + drm_fb_helper_cfb_fillrect(info, rect); > +} > + > +static void drm_fbdev_fb_copyarea(struct fb_info *info, > + const struct fb_copyarea *area) > +{ > + struct drm_fb_helper *fb_helper = info->par; > + struct drm_client_buffer *buffer = fb_helper->buffer; > + > + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) > + drm_fb_helper_sys_copyarea(info, area); > + else > + drm_fb_helper_cfb_copyarea(info, area); > +} > + > +static void drm_fbdev_fb_imageblit(struct fb_info *info, > + const struct fb_image *image) > +{ > + struct drm_fb_helper *fb_helper = info->par; > + struct drm_client_buffer *buffer = fb_helper->buffer; > + > + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) > + drm_fb_helper_sys_imageblit(info, image); > + else > + drm_fb_helper_cfb_imageblit(info, image); > +} > + > static const struct fb_ops drm_fbdev_fb_ops = { > .owner = THIS_MODULE, > DRM_FB_HELPER_DEFAULT_OPS, > @@ -2034,11 +2223,11 @@ static const struct fb_ops drm_fbdev_fb_ops = { > .fb_release = drm_fbdev_fb_release, > .fb_destroy = drm_fbdev_fb_destroy, > .fb_mmap = drm_fbdev_fb_mmap, > - .fb_read = drm_fb_helper_sys_read, > - .fb_write = drm_fb_helper_sys_write, > - .fb_fillrect = drm_fb_helper_sys_fillrect, > - .fb_copyarea = drm_fb_helper_sys_copyarea, > - .fb_imageblit = drm_fb_helper_sys_imageblit, > + .fb_read = drm_fbdev_fb_read, > + .fb_write = drm_fbdev_fb_write, > + .fb_fillrect = drm_fbdev_fb_fillrect, > + .fb_copyarea = drm_fbdev_fb_copyarea, > + .fb_imageblit = drm_fbdev_fb_imageblit, > }; > > static struct fb_deferred_io drm_fbdev_defio = { > diff --git a/include/drm/drm_mode_config.h b/include/drm/drm_mode_config.h > index 5ffbb4ed5b35..ab424ddd7665 100644 > --- a/include/drm/drm_mode_config.h > +++ b/include/drm/drm_mode_config.h > @@ -877,18 +877,6 @@ struct drm_mode_config { > */ > bool prefer_shadow_fbdev; > > - /** > - * @fbdev_use_iomem: > - * > - * Set to true if framebuffer reside in iomem. > - * When set to true memcpy_toio() is used when copying the framebuffer in > - * drm_fb_helper.drm_fb_helper_dirty_blit_real(). > - * > - * FIXME: This should be replaced with a per-mapping is_iomem > - * flag (like ttm does), and then used everywhere in fbdev code. > - */ > - bool fbdev_use_iomem; > - > /** > * @quirk_addfb_prefer_xbgr_30bpp: > * > -- > 2.28.0
Hi On Fri, 16 Oct 2020 14:03:47 +0200 Sam Ravnborg <sam@ravnborg.org> wrote: > Hi Thomas. > > On Thu, Oct 15, 2020 at 02:38:06PM +0200, Thomas Zimmermann wrote: > > At least sparc64 requires I/O-specific access to framebuffers. This > > patch updates the fbdev console accordingly. > > > > For drivers with direct access to the framebuffer memory, the callback > > functions in struct fb_ops test for the type of memory and call the rsp > > fb_sys_ of fb_cfb_ functions. > > > > For drivers that employ a shadow buffer, fbdev's blit function retrieves > > the framebuffer address as struct dma_buf_map, and uses dma_buf_map > > interfaces to access the buffer. > > > > The bochs driver on sparc64 uses a workaround to flag the framebuffer as > > I/O memory and avoid a HW exception. With the introduction of struct > > dma_buf_map, this is not required any longer. The patch removes the rsp > > code from both, bochs and fbdev. > > > > v4: > > * move dma_buf_map changes into separate patch (Daniel) > > * TODO list: comment on fbdev updates (Daniel) > > > > Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> > > The original workaround fixed it so we could run qemu with the > -nographic option. > > So I went ahead and tried to run quemu version: > v5.0.0-1970-g0b100c8e72-dirty. > And with the BOCHS driver built-in. > > With the following command line: > qemu-system-sparc64 -m 512 -kernel vmlinux -append console=ttyS0 -nographic > > Behaviour was the same before and after applying this patch. > (panic due to VFS: Unable to mount root fs on unknown-block(0,0)) > So I consider it fixed for real now and not just a workaround. > > I also tested with: > qemu-system-sparc64 -m 512 -kernel vmlinux -append console=ttyS0 -serial > stdio > > and it worked in both cases too. FTR, you booted a kernel and got graphics output. The error is simply that there was no disk to mount? Best regards Thomas > > All the comments above so future-me have an easier time finding how to > reproduce. > > Tested-by: Sam Ravnborg <sam@ravnborg.org> > > Sam > > > --- > > Documentation/gpu/todo.rst | 19 ++- > > drivers/gpu/drm/bochs/bochs_kms.c | 1 - > > drivers/gpu/drm/drm_fb_helper.c | 217 ++++++++++++++++++++++++++++-- > > include/drm/drm_mode_config.h | 12 -- > > 4 files changed, 220 insertions(+), 29 deletions(-) > > > > diff --git a/Documentation/gpu/todo.rst b/Documentation/gpu/todo.rst > > index 7e6fc3c04add..638b7f704339 100644 > > --- a/Documentation/gpu/todo.rst > > +++ b/Documentation/gpu/todo.rst > > @@ -197,13 +197,28 @@ Convert drivers to use drm_fbdev_generic_setup() > > ------------------------------------------------ > > > > Most drivers can use drm_fbdev_generic_setup(). Driver have to implement > > -atomic modesetting and GEM vmap support. Current generic fbdev emulation > > -expects the framebuffer in system memory (or system-like memory). > > +atomic modesetting and GEM vmap support. Historically, generic fbdev > > emulation +expected the framebuffer in system memory or system-like > > memory. By employing +struct dma_buf_map, drivers with frambuffers in I/O > > memory can be supported +as well. > > > > Contact: Maintainer of the driver you plan to convert > > > > Level: Intermediate > > > > +Reimplement functions in drm_fbdev_fb_ops without fbdev > > +------------------------------------------------------- > > + > > +A number of callback functions in drm_fbdev_fb_ops could benefit from > > +being rewritten without dependencies on the fbdev module. Some of the > > +helpers could further benefit from using struct dma_buf_map instead of > > +raw pointers. > > + > > +Contact: Thomas Zimmermann <tzimmermann@suse.de>, Daniel Vetter > > + > > +Level: Advanced > > + > > + > > drm_framebuffer_funcs and drm_mode_config_funcs.fb_create cleanup > > ----------------------------------------------------------------- > > > > diff --git a/drivers/gpu/drm/bochs/bochs_kms.c > > b/drivers/gpu/drm/bochs/bochs_kms.c index 13d0d04c4457..853081d186d5 > > 100644 --- a/drivers/gpu/drm/bochs/bochs_kms.c > > +++ b/drivers/gpu/drm/bochs/bochs_kms.c > > @@ -151,7 +151,6 @@ int bochs_kms_init(struct bochs_device *bochs) > > bochs->dev->mode_config.preferred_depth = 24; > > bochs->dev->mode_config.prefer_shadow = 0; > > bochs->dev->mode_config.prefer_shadow_fbdev = 1; > > - bochs->dev->mode_config.fbdev_use_iomem = true; > > bochs->dev->mode_config.quirk_addfb_prefer_host_byte_order = > > true; > > bochs->dev->mode_config.funcs = &bochs_mode_funcs; > > diff --git a/drivers/gpu/drm/drm_fb_helper.c > > b/drivers/gpu/drm/drm_fb_helper.c index 6212cd7cde1d..462b0c130ebb 100644 > > --- a/drivers/gpu/drm/drm_fb_helper.c > > +++ b/drivers/gpu/drm/drm_fb_helper.c > > @@ -372,24 +372,22 @@ static void drm_fb_helper_resume_worker(struct > > work_struct *work) } > > > > static void drm_fb_helper_dirty_blit_real(struct drm_fb_helper > > *fb_helper, > > - struct drm_clip_rect *clip) > > + struct drm_clip_rect *clip, > > + struct dma_buf_map *dst) > > { > > struct drm_framebuffer *fb = fb_helper->fb; > > unsigned int cpp = fb->format->cpp[0]; > > size_t offset = clip->y1 * fb->pitches[0] + clip->x1 * cpp; > > void *src = fb_helper->fbdev->screen_buffer + offset; > > - void *dst = fb_helper->buffer->map.vaddr + offset; > > size_t len = (clip->x2 - clip->x1) * cpp; > > unsigned int y; > > > > - for (y = clip->y1; y < clip->y2; y++) { > > - if (!fb_helper->dev->mode_config.fbdev_use_iomem) > > - memcpy(dst, src, len); > > - else > > - memcpy_toio((void __iomem *)dst, src, len); > > + dma_buf_map_incr(dst, offset); /* go to first pixel within clip > > rect */ > > + for (y = clip->y1; y < clip->y2; y++) { > > + dma_buf_map_memcpy_to(dst, src, len); > > + dma_buf_map_incr(dst, fb->pitches[0]); > > src += fb->pitches[0]; > > - dst += fb->pitches[0]; > > } > > } > > > > @@ -417,8 +415,9 @@ static void drm_fb_helper_dirty_work(struct > > work_struct *work) ret = drm_client_buffer_vmap(helper->buffer, &map); > > if (ret) > > return; > > - drm_fb_helper_dirty_blit_real(helper, > > &clip_copy); > > + drm_fb_helper_dirty_blit_real(helper, > > &clip_copy, &map); } > > + > > if (helper->fb->funcs->dirty) > > helper->fb->funcs->dirty(helper->fb, NULL, 0, 0, > > &clip_copy, 1); > > @@ -755,6 +754,136 @@ void drm_fb_helper_sys_imageblit(struct fb_info > > *info, } > > EXPORT_SYMBOL(drm_fb_helper_sys_imageblit); > > > > +static ssize_t drm_fb_helper_cfb_read(struct fb_info *info, char __user > > *buf, > > + size_t count, loff_t *ppos) > > +{ > > + unsigned long p = *ppos; > > + u8 *dst; > > + u8 __iomem *src; > > + int c, err = 0; > > + unsigned long total_size; > > + unsigned long alloc_size; > > + ssize_t ret = 0; > > + > > + if (info->state != FBINFO_STATE_RUNNING) > > + return -EPERM; > > + > > + total_size = info->screen_size; > > + > > + if (total_size == 0) > > + total_size = info->fix.smem_len; > > + > > + if (p >= total_size) > > + return 0; > > + > > + if (count >= total_size) > > + count = total_size; > > + > > + if (count + p > total_size) > > + count = total_size - p; > > + > > + src = (u8 __iomem *)(info->screen_base + p); > > + > > + alloc_size = min(count, PAGE_SIZE); > > + > > + dst = kmalloc(alloc_size, GFP_KERNEL); > > + if (!dst) > > + return -ENOMEM; > > + > > + while (count) { > > + c = min(count, alloc_size); > > + > > + memcpy_fromio(dst, src, c); > > + if (copy_to_user(buf, dst, c)) { > > + err = -EFAULT; > > + break; > > + } > > + > > + src += c; > > + *ppos += c; > > + buf += c; > > + ret += c; > > + count -= c; > > + } > > + > > + kfree(dst); > > + > > + if (err) > > + return err; > > + > > + return ret; > > +} > > + > > +static ssize_t drm_fb_helper_cfb_write(struct fb_info *info, const char > > __user *buf, > > + size_t count, loff_t *ppos) > > +{ > > + unsigned long p = *ppos; > > + u8 *src; > > + u8 __iomem *dst; > > + int c, err = 0; > > + unsigned long total_size; > > + unsigned long alloc_size; > > + ssize_t ret = 0; > > + > > + if (info->state != FBINFO_STATE_RUNNING) > > + return -EPERM; > > + > > + total_size = info->screen_size; > > + > > + if (total_size == 0) > > + total_size = info->fix.smem_len; > > + > > + if (p > total_size) > > + return -EFBIG; > > + > > + if (count > total_size) { > > + err = -EFBIG; > > + count = total_size; > > + } > > + > > + if (count + p > total_size) { > > + /* > > + * The framebuffer is too small. We do the > > + * copy operation, but return an error code > > + * afterwards. Taken from fbdev. > > + */ > > + if (!err) > > + err = -ENOSPC; > > + count = total_size - p; > > + } > > + > > + alloc_size = min(count, PAGE_SIZE); > > + > > + src = kmalloc(alloc_size, GFP_KERNEL); > > + if (!src) > > + return -ENOMEM; > > + > > + dst = (u8 __iomem *)(info->screen_base + p); > > + > > + while (count) { > > + c = min(count, alloc_size); > > + > > + if (copy_from_user(src, buf, c)) { > > + err = -EFAULT; > > + break; > > + } > > + memcpy_toio(dst, src, c); > > + > > + dst += c; > > + *ppos += c; > > + buf += c; > > + ret += c; > > + count -= c; > > + } > > + > > + kfree(src); > > + > > + if (err) > > + return err; > > + > > + return ret; > > +} > > + > > /** > > * drm_fb_helper_cfb_fillrect - wrapper around cfb_fillrect > > * @info: fbdev registered by the helper > > @@ -2027,6 +2156,66 @@ static int drm_fbdev_fb_mmap(struct fb_info *info, > > struct vm_area_struct *vma) return -ENODEV; > > } > > > > +static ssize_t drm_fbdev_fb_read(struct fb_info *info, char __user *buf, > > + size_t count, loff_t *ppos) > > +{ > > + struct drm_fb_helper *fb_helper = info->par; > > + struct drm_client_buffer *buffer = fb_helper->buffer; > > + > > + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) > > + return drm_fb_helper_sys_read(info, buf, count, ppos); > > + else > > + return drm_fb_helper_cfb_read(info, buf, count, ppos); > > +} > > + > > +static ssize_t drm_fbdev_fb_write(struct fb_info *info, const char > > __user *buf, > > + size_t count, loff_t *ppos) > > +{ > > + struct drm_fb_helper *fb_helper = info->par; > > + struct drm_client_buffer *buffer = fb_helper->buffer; > > + > > + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) > > + return drm_fb_helper_sys_write(info, buf, count, ppos); > > + else > > + return drm_fb_helper_cfb_write(info, buf, count, ppos); > > +} > > + > > +static void drm_fbdev_fb_fillrect(struct fb_info *info, > > + const struct fb_fillrect *rect) > > +{ > > + struct drm_fb_helper *fb_helper = info->par; > > + struct drm_client_buffer *buffer = fb_helper->buffer; > > + > > + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) > > + drm_fb_helper_sys_fillrect(info, rect); > > + else > > + drm_fb_helper_cfb_fillrect(info, rect); > > +} > > + > > +static void drm_fbdev_fb_copyarea(struct fb_info *info, > > + const struct fb_copyarea *area) > > +{ > > + struct drm_fb_helper *fb_helper = info->par; > > + struct drm_client_buffer *buffer = fb_helper->buffer; > > + > > + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) > > + drm_fb_helper_sys_copyarea(info, area); > > + else > > + drm_fb_helper_cfb_copyarea(info, area); > > +} > > + > > +static void drm_fbdev_fb_imageblit(struct fb_info *info, > > + const struct fb_image *image) > > +{ > > + struct drm_fb_helper *fb_helper = info->par; > > + struct drm_client_buffer *buffer = fb_helper->buffer; > > + > > + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) > > + drm_fb_helper_sys_imageblit(info, image); > > + else > > + drm_fb_helper_cfb_imageblit(info, image); > > +} > > + > > static const struct fb_ops drm_fbdev_fb_ops = { > > .owner = THIS_MODULE, > > DRM_FB_HELPER_DEFAULT_OPS, > > @@ -2034,11 +2223,11 @@ static const struct fb_ops drm_fbdev_fb_ops = { > > .fb_release = drm_fbdev_fb_release, > > .fb_destroy = drm_fbdev_fb_destroy, > > .fb_mmap = drm_fbdev_fb_mmap, > > - .fb_read = drm_fb_helper_sys_read, > > - .fb_write = drm_fb_helper_sys_write, > > - .fb_fillrect = drm_fb_helper_sys_fillrect, > > - .fb_copyarea = drm_fb_helper_sys_copyarea, > > - .fb_imageblit = drm_fb_helper_sys_imageblit, > > + .fb_read = drm_fbdev_fb_read, > > + .fb_write = drm_fbdev_fb_write, > > + .fb_fillrect = drm_fbdev_fb_fillrect, > > + .fb_copyarea = drm_fbdev_fb_copyarea, > > + .fb_imageblit = drm_fbdev_fb_imageblit, > > }; > > > > static struct fb_deferred_io drm_fbdev_defio = { > > diff --git a/include/drm/drm_mode_config.h b/include/drm/drm_mode_config.h > > index 5ffbb4ed5b35..ab424ddd7665 100644 > > --- a/include/drm/drm_mode_config.h > > +++ b/include/drm/drm_mode_config.h > > @@ -877,18 +877,6 @@ struct drm_mode_config { > > */ > > bool prefer_shadow_fbdev; > > > > - /** > > - * @fbdev_use_iomem: > > - * > > - * Set to true if framebuffer reside in iomem. > > - * When set to true memcpy_toio() is used when copying the > > framebuffer in > > - * drm_fb_helper.drm_fb_helper_dirty_blit_real(). > > - * > > - * FIXME: This should be replaced with a per-mapping is_iomem > > - * flag (like ttm does), and then used everywhere in fbdev code. > > - */ > > - bool fbdev_use_iomem; > > - > > /** > > * @quirk_addfb_prefer_xbgr_30bpp: > > * > > -- > > 2.28.0
On Fri, Oct 16, 2020 at 02:19:42PM +0200, Thomas Zimmermann wrote: > Hi > > On Fri, 16 Oct 2020 14:03:47 +0200 Sam Ravnborg <sam@ravnborg.org> wrote: > > > Hi Thomas. > > > > On Thu, Oct 15, 2020 at 02:38:06PM +0200, Thomas Zimmermann wrote: > > > At least sparc64 requires I/O-specific access to framebuffers. This > > > patch updates the fbdev console accordingly. > > > > > > For drivers with direct access to the framebuffer memory, the callback > > > functions in struct fb_ops test for the type of memory and call the rsp > > > fb_sys_ of fb_cfb_ functions. > > > > > > For drivers that employ a shadow buffer, fbdev's blit function retrieves > > > the framebuffer address as struct dma_buf_map, and uses dma_buf_map > > > interfaces to access the buffer. > > > > > > The bochs driver on sparc64 uses a workaround to flag the framebuffer as > > > I/O memory and avoid a HW exception. With the introduction of struct > > > dma_buf_map, this is not required any longer. The patch removes the rsp > > > code from both, bochs and fbdev. > > > > > > v4: > > > * move dma_buf_map changes into separate patch (Daniel) > > > * TODO list: comment on fbdev updates (Daniel) > > > > > > Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> > > > > The original workaround fixed it so we could run qemu with the > > -nographic option. > > > > So I went ahead and tried to run quemu version: > > v5.0.0-1970-g0b100c8e72-dirty. > > And with the BOCHS driver built-in. > > > > With the following command line: > > qemu-system-sparc64 -m 512 -kernel vmlinux -append console=ttyS0 -nographic > > > > Behaviour was the same before and after applying this patch. > > (panic due to VFS: Unable to mount root fs on unknown-block(0,0)) > > So I consider it fixed for real now and not just a workaround. > > > > I also tested with: > > qemu-system-sparc64 -m 512 -kernel vmlinux -append console=ttyS0 -serial > > stdio > > > > and it worked in both cases too. > > FTR, you booted a kernel and got graphics output. The error is simply that > there was no disk to mount? The short version "Yes". The longer version: With "qemu-system-sparc64 -m 512 -kernel vmlinux -append console=ttyS0 -serial stdio" I got graphical output - one penguin. With "qemu-system-sparc64 -m 512 -kernel vmlinux -append console=ttyS0 -nographic" I got no graphical output, as implied by the -nographic option. But the boot continued - where it would panic before when we accessed IO memory as system memory. In both cases I got an error because I had not specified any rootfs, so qemu failed to mount any rootfs. So expected. Sam > > Best regards > Thomas > > > > > All the comments above so future-me have an easier time finding how to > > reproduce. > > > > Tested-by: Sam Ravnborg <sam@ravnborg.org> > > > > Sam > > > > > --- > > > Documentation/gpu/todo.rst | 19 ++- > > > drivers/gpu/drm/bochs/bochs_kms.c | 1 - > > > drivers/gpu/drm/drm_fb_helper.c | 217 ++++++++++++++++++++++++++++-- > > > include/drm/drm_mode_config.h | 12 -- > > > 4 files changed, 220 insertions(+), 29 deletions(-) > > > > > > diff --git a/Documentation/gpu/todo.rst b/Documentation/gpu/todo.rst > > > index 7e6fc3c04add..638b7f704339 100644 > > > --- a/Documentation/gpu/todo.rst > > > +++ b/Documentation/gpu/todo.rst > > > @@ -197,13 +197,28 @@ Convert drivers to use drm_fbdev_generic_setup() > > > ------------------------------------------------ > > > > > > Most drivers can use drm_fbdev_generic_setup(). Driver have to implement > > > -atomic modesetting and GEM vmap support. Current generic fbdev emulation > > > -expects the framebuffer in system memory (or system-like memory). > > > +atomic modesetting and GEM vmap support. Historically, generic fbdev > > > emulation +expected the framebuffer in system memory or system-like > > > memory. By employing +struct dma_buf_map, drivers with frambuffers in I/O > > > memory can be supported +as well. > > > > > > Contact: Maintainer of the driver you plan to convert > > > > > > Level: Intermediate > > > > > > +Reimplement functions in drm_fbdev_fb_ops without fbdev > > > +------------------------------------------------------- > > > + > > > +A number of callback functions in drm_fbdev_fb_ops could benefit from > > > +being rewritten without dependencies on the fbdev module. Some of the > > > +helpers could further benefit from using struct dma_buf_map instead of > > > +raw pointers. > > > + > > > +Contact: Thomas Zimmermann <tzimmermann@suse.de>, Daniel Vetter > > > + > > > +Level: Advanced > > > + > > > + > > > drm_framebuffer_funcs and drm_mode_config_funcs.fb_create cleanup > > > ----------------------------------------------------------------- > > > > > > diff --git a/drivers/gpu/drm/bochs/bochs_kms.c > > > b/drivers/gpu/drm/bochs/bochs_kms.c index 13d0d04c4457..853081d186d5 > > > 100644 --- a/drivers/gpu/drm/bochs/bochs_kms.c > > > +++ b/drivers/gpu/drm/bochs/bochs_kms.c > > > @@ -151,7 +151,6 @@ int bochs_kms_init(struct bochs_device *bochs) > > > bochs->dev->mode_config.preferred_depth = 24; > > > bochs->dev->mode_config.prefer_shadow = 0; > > > bochs->dev->mode_config.prefer_shadow_fbdev = 1; > > > - bochs->dev->mode_config.fbdev_use_iomem = true; > > > bochs->dev->mode_config.quirk_addfb_prefer_host_byte_order = > > > true; > > > bochs->dev->mode_config.funcs = &bochs_mode_funcs; > > > diff --git a/drivers/gpu/drm/drm_fb_helper.c > > > b/drivers/gpu/drm/drm_fb_helper.c index 6212cd7cde1d..462b0c130ebb 100644 > > > --- a/drivers/gpu/drm/drm_fb_helper.c > > > +++ b/drivers/gpu/drm/drm_fb_helper.c > > > @@ -372,24 +372,22 @@ static void drm_fb_helper_resume_worker(struct > > > work_struct *work) } > > > > > > static void drm_fb_helper_dirty_blit_real(struct drm_fb_helper > > > *fb_helper, > > > - struct drm_clip_rect *clip) > > > + struct drm_clip_rect *clip, > > > + struct dma_buf_map *dst) > > > { > > > struct drm_framebuffer *fb = fb_helper->fb; > > > unsigned int cpp = fb->format->cpp[0]; > > > size_t offset = clip->y1 * fb->pitches[0] + clip->x1 * cpp; > > > void *src = fb_helper->fbdev->screen_buffer + offset; > > > - void *dst = fb_helper->buffer->map.vaddr + offset; > > > size_t len = (clip->x2 - clip->x1) * cpp; > > > unsigned int y; > > > > > > - for (y = clip->y1; y < clip->y2; y++) { > > > - if (!fb_helper->dev->mode_config.fbdev_use_iomem) > > > - memcpy(dst, src, len); > > > - else > > > - memcpy_toio((void __iomem *)dst, src, len); > > > + dma_buf_map_incr(dst, offset); /* go to first pixel within clip > > > rect */ > > > + for (y = clip->y1; y < clip->y2; y++) { > > > + dma_buf_map_memcpy_to(dst, src, len); > > > + dma_buf_map_incr(dst, fb->pitches[0]); > > > src += fb->pitches[0]; > > > - dst += fb->pitches[0]; > > > } > > > } > > > > > > @@ -417,8 +415,9 @@ static void drm_fb_helper_dirty_work(struct > > > work_struct *work) ret = drm_client_buffer_vmap(helper->buffer, &map); > > > if (ret) > > > return; > > > - drm_fb_helper_dirty_blit_real(helper, > > > &clip_copy); > > > + drm_fb_helper_dirty_blit_real(helper, > > > &clip_copy, &map); } > > > + > > > if (helper->fb->funcs->dirty) > > > helper->fb->funcs->dirty(helper->fb, NULL, 0, 0, > > > &clip_copy, 1); > > > @@ -755,6 +754,136 @@ void drm_fb_helper_sys_imageblit(struct fb_info > > > *info, } > > > EXPORT_SYMBOL(drm_fb_helper_sys_imageblit); > > > > > > +static ssize_t drm_fb_helper_cfb_read(struct fb_info *info, char __user > > > *buf, > > > + size_t count, loff_t *ppos) > > > +{ > > > + unsigned long p = *ppos; > > > + u8 *dst; > > > + u8 __iomem *src; > > > + int c, err = 0; > > > + unsigned long total_size; > > > + unsigned long alloc_size; > > > + ssize_t ret = 0; > > > + > > > + if (info->state != FBINFO_STATE_RUNNING) > > > + return -EPERM; > > > + > > > + total_size = info->screen_size; > > > + > > > + if (total_size == 0) > > > + total_size = info->fix.smem_len; > > > + > > > + if (p >= total_size) > > > + return 0; > > > + > > > + if (count >= total_size) > > > + count = total_size; > > > + > > > + if (count + p > total_size) > > > + count = total_size - p; > > > + > > > + src = (u8 __iomem *)(info->screen_base + p); > > > + > > > + alloc_size = min(count, PAGE_SIZE); > > > + > > > + dst = kmalloc(alloc_size, GFP_KERNEL); > > > + if (!dst) > > > + return -ENOMEM; > > > + > > > + while (count) { > > > + c = min(count, alloc_size); > > > + > > > + memcpy_fromio(dst, src, c); > > > + if (copy_to_user(buf, dst, c)) { > > > + err = -EFAULT; > > > + break; > > > + } > > > + > > > + src += c; > > > + *ppos += c; > > > + buf += c; > > > + ret += c; > > > + count -= c; > > > + } > > > + > > > + kfree(dst); > > > + > > > + if (err) > > > + return err; > > > + > > > + return ret; > > > +} > > > + > > > +static ssize_t drm_fb_helper_cfb_write(struct fb_info *info, const char > > > __user *buf, > > > + size_t count, loff_t *ppos) > > > +{ > > > + unsigned long p = *ppos; > > > + u8 *src; > > > + u8 __iomem *dst; > > > + int c, err = 0; > > > + unsigned long total_size; > > > + unsigned long alloc_size; > > > + ssize_t ret = 0; > > > + > > > + if (info->state != FBINFO_STATE_RUNNING) > > > + return -EPERM; > > > + > > > + total_size = info->screen_size; > > > + > > > + if (total_size == 0) > > > + total_size = info->fix.smem_len; > > > + > > > + if (p > total_size) > > > + return -EFBIG; > > > + > > > + if (count > total_size) { > > > + err = -EFBIG; > > > + count = total_size; > > > + } > > > + > > > + if (count + p > total_size) { > > > + /* > > > + * The framebuffer is too small. We do the > > > + * copy operation, but return an error code > > > + * afterwards. Taken from fbdev. > > > + */ > > > + if (!err) > > > + err = -ENOSPC; > > > + count = total_size - p; > > > + } > > > + > > > + alloc_size = min(count, PAGE_SIZE); > > > + > > > + src = kmalloc(alloc_size, GFP_KERNEL); > > > + if (!src) > > > + return -ENOMEM; > > > + > > > + dst = (u8 __iomem *)(info->screen_base + p); > > > + > > > + while (count) { > > > + c = min(count, alloc_size); > > > + > > > + if (copy_from_user(src, buf, c)) { > > > + err = -EFAULT; > > > + break; > > > + } > > > + memcpy_toio(dst, src, c); > > > + > > > + dst += c; > > > + *ppos += c; > > > + buf += c; > > > + ret += c; > > > + count -= c; > > > + } > > > + > > > + kfree(src); > > > + > > > + if (err) > > > + return err; > > > + > > > + return ret; > > > +} > > > + > > > /** > > > * drm_fb_helper_cfb_fillrect - wrapper around cfb_fillrect > > > * @info: fbdev registered by the helper > > > @@ -2027,6 +2156,66 @@ static int drm_fbdev_fb_mmap(struct fb_info *info, > > > struct vm_area_struct *vma) return -ENODEV; > > > } > > > > > > +static ssize_t drm_fbdev_fb_read(struct fb_info *info, char __user *buf, > > > + size_t count, loff_t *ppos) > > > +{ > > > + struct drm_fb_helper *fb_helper = info->par; > > > + struct drm_client_buffer *buffer = fb_helper->buffer; > > > + > > > + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) > > > + return drm_fb_helper_sys_read(info, buf, count, ppos); > > > + else > > > + return drm_fb_helper_cfb_read(info, buf, count, ppos); > > > +} > > > + > > > +static ssize_t drm_fbdev_fb_write(struct fb_info *info, const char > > > __user *buf, > > > + size_t count, loff_t *ppos) > > > +{ > > > + struct drm_fb_helper *fb_helper = info->par; > > > + struct drm_client_buffer *buffer = fb_helper->buffer; > > > + > > > + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) > > > + return drm_fb_helper_sys_write(info, buf, count, ppos); > > > + else > > > + return drm_fb_helper_cfb_write(info, buf, count, ppos); > > > +} > > > + > > > +static void drm_fbdev_fb_fillrect(struct fb_info *info, > > > + const struct fb_fillrect *rect) > > > +{ > > > + struct drm_fb_helper *fb_helper = info->par; > > > + struct drm_client_buffer *buffer = fb_helper->buffer; > > > + > > > + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) > > > + drm_fb_helper_sys_fillrect(info, rect); > > > + else > > > + drm_fb_helper_cfb_fillrect(info, rect); > > > +} > > > + > > > +static void drm_fbdev_fb_copyarea(struct fb_info *info, > > > + const struct fb_copyarea *area) > > > +{ > > > + struct drm_fb_helper *fb_helper = info->par; > > > + struct drm_client_buffer *buffer = fb_helper->buffer; > > > + > > > + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) > > > + drm_fb_helper_sys_copyarea(info, area); > > > + else > > > + drm_fb_helper_cfb_copyarea(info, area); > > > +} > > > + > > > +static void drm_fbdev_fb_imageblit(struct fb_info *info, > > > + const struct fb_image *image) > > > +{ > > > + struct drm_fb_helper *fb_helper = info->par; > > > + struct drm_client_buffer *buffer = fb_helper->buffer; > > > + > > > + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) > > > + drm_fb_helper_sys_imageblit(info, image); > > > + else > > > + drm_fb_helper_cfb_imageblit(info, image); > > > +} > > > + > > > static const struct fb_ops drm_fbdev_fb_ops = { > > > .owner = THIS_MODULE, > > > DRM_FB_HELPER_DEFAULT_OPS, > > > @@ -2034,11 +2223,11 @@ static const struct fb_ops drm_fbdev_fb_ops = { > > > .fb_release = drm_fbdev_fb_release, > > > .fb_destroy = drm_fbdev_fb_destroy, > > > .fb_mmap = drm_fbdev_fb_mmap, > > > - .fb_read = drm_fb_helper_sys_read, > > > - .fb_write = drm_fb_helper_sys_write, > > > - .fb_fillrect = drm_fb_helper_sys_fillrect, > > > - .fb_copyarea = drm_fb_helper_sys_copyarea, > > > - .fb_imageblit = drm_fb_helper_sys_imageblit, > > > + .fb_read = drm_fbdev_fb_read, > > > + .fb_write = drm_fbdev_fb_write, > > > + .fb_fillrect = drm_fbdev_fb_fillrect, > > > + .fb_copyarea = drm_fbdev_fb_copyarea, > > > + .fb_imageblit = drm_fbdev_fb_imageblit, > > > }; > > > > > > static struct fb_deferred_io drm_fbdev_defio = { > > > diff --git a/include/drm/drm_mode_config.h b/include/drm/drm_mode_config.h > > > index 5ffbb4ed5b35..ab424ddd7665 100644 > > > --- a/include/drm/drm_mode_config.h > > > +++ b/include/drm/drm_mode_config.h > > > @@ -877,18 +877,6 @@ struct drm_mode_config { > > > */ > > > bool prefer_shadow_fbdev; > > > > > > - /** > > > - * @fbdev_use_iomem: > > > - * > > > - * Set to true if framebuffer reside in iomem. > > > - * When set to true memcpy_toio() is used when copying the > > > framebuffer in > > > - * drm_fb_helper.drm_fb_helper_dirty_blit_real(). > > > - * > > > - * FIXME: This should be replaced with a per-mapping is_iomem > > > - * flag (like ttm does), and then used everywhere in fbdev code. > > > - */ > > > - bool fbdev_use_iomem; > > > - > > > /** > > > * @quirk_addfb_prefer_xbgr_30bpp: > > > * > > > -- > > > 2.28.0 > > > > -- > Thomas Zimmermann > Graphics Driver Developer > SUSE Software Solutions Germany GmbH > Maxfeldstr. 5, 90409 Nürnberg, Germany > (HRB 36809, AG Nürnberg) > Geschäftsführer: Felix Imendörffer
diff --git a/Documentation/gpu/todo.rst b/Documentation/gpu/todo.rst index 7e6fc3c04add..638b7f704339 100644 --- a/Documentation/gpu/todo.rst +++ b/Documentation/gpu/todo.rst @@ -197,13 +197,28 @@ Convert drivers to use drm_fbdev_generic_setup() ------------------------------------------------ Most drivers can use drm_fbdev_generic_setup(). Driver have to implement -atomic modesetting and GEM vmap support. Current generic fbdev emulation -expects the framebuffer in system memory (or system-like memory). +atomic modesetting and GEM vmap support. Historically, generic fbdev emulation +expected the framebuffer in system memory or system-like memory. By employing +struct dma_buf_map, drivers with frambuffers in I/O memory can be supported +as well. Contact: Maintainer of the driver you plan to convert Level: Intermediate +Reimplement functions in drm_fbdev_fb_ops without fbdev +------------------------------------------------------- + +A number of callback functions in drm_fbdev_fb_ops could benefit from +being rewritten without dependencies on the fbdev module. Some of the +helpers could further benefit from using struct dma_buf_map instead of +raw pointers. + +Contact: Thomas Zimmermann <tzimmermann@suse.de>, Daniel Vetter + +Level: Advanced + + drm_framebuffer_funcs and drm_mode_config_funcs.fb_create cleanup ----------------------------------------------------------------- diff --git a/drivers/gpu/drm/bochs/bochs_kms.c b/drivers/gpu/drm/bochs/bochs_kms.c index 13d0d04c4457..853081d186d5 100644 --- a/drivers/gpu/drm/bochs/bochs_kms.c +++ b/drivers/gpu/drm/bochs/bochs_kms.c @@ -151,7 +151,6 @@ int bochs_kms_init(struct bochs_device *bochs) bochs->dev->mode_config.preferred_depth = 24; bochs->dev->mode_config.prefer_shadow = 0; bochs->dev->mode_config.prefer_shadow_fbdev = 1; - bochs->dev->mode_config.fbdev_use_iomem = true; bochs->dev->mode_config.quirk_addfb_prefer_host_byte_order = true; bochs->dev->mode_config.funcs = &bochs_mode_funcs; diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c index 6212cd7cde1d..462b0c130ebb 100644 --- a/drivers/gpu/drm/drm_fb_helper.c +++ b/drivers/gpu/drm/drm_fb_helper.c @@ -372,24 +372,22 @@ static void drm_fb_helper_resume_worker(struct work_struct *work) } static void drm_fb_helper_dirty_blit_real(struct drm_fb_helper *fb_helper, - struct drm_clip_rect *clip) + struct drm_clip_rect *clip, + struct dma_buf_map *dst) { struct drm_framebuffer *fb = fb_helper->fb; unsigned int cpp = fb->format->cpp[0]; size_t offset = clip->y1 * fb->pitches[0] + clip->x1 * cpp; void *src = fb_helper->fbdev->screen_buffer + offset; - void *dst = fb_helper->buffer->map.vaddr + offset; size_t len = (clip->x2 - clip->x1) * cpp; unsigned int y; - for (y = clip->y1; y < clip->y2; y++) { - if (!fb_helper->dev->mode_config.fbdev_use_iomem) - memcpy(dst, src, len); - else - memcpy_toio((void __iomem *)dst, src, len); + dma_buf_map_incr(dst, offset); /* go to first pixel within clip rect */ + for (y = clip->y1; y < clip->y2; y++) { + dma_buf_map_memcpy_to(dst, src, len); + dma_buf_map_incr(dst, fb->pitches[0]); src += fb->pitches[0]; - dst += fb->pitches[0]; } } @@ -417,8 +415,9 @@ static void drm_fb_helper_dirty_work(struct work_struct *work) ret = drm_client_buffer_vmap(helper->buffer, &map); if (ret) return; - drm_fb_helper_dirty_blit_real(helper, &clip_copy); + drm_fb_helper_dirty_blit_real(helper, &clip_copy, &map); } + if (helper->fb->funcs->dirty) helper->fb->funcs->dirty(helper->fb, NULL, 0, 0, &clip_copy, 1); @@ -755,6 +754,136 @@ void drm_fb_helper_sys_imageblit(struct fb_info *info, } EXPORT_SYMBOL(drm_fb_helper_sys_imageblit); +static ssize_t drm_fb_helper_cfb_read(struct fb_info *info, char __user *buf, + size_t count, loff_t *ppos) +{ + unsigned long p = *ppos; + u8 *dst; + u8 __iomem *src; + int c, err = 0; + unsigned long total_size; + unsigned long alloc_size; + ssize_t ret = 0; + + if (info->state != FBINFO_STATE_RUNNING) + return -EPERM; + + total_size = info->screen_size; + + if (total_size == 0) + total_size = info->fix.smem_len; + + if (p >= total_size) + return 0; + + if (count >= total_size) + count = total_size; + + if (count + p > total_size) + count = total_size - p; + + src = (u8 __iomem *)(info->screen_base + p); + + alloc_size = min(count, PAGE_SIZE); + + dst = kmalloc(alloc_size, GFP_KERNEL); + if (!dst) + return -ENOMEM; + + while (count) { + c = min(count, alloc_size); + + memcpy_fromio(dst, src, c); + if (copy_to_user(buf, dst, c)) { + err = -EFAULT; + break; + } + + src += c; + *ppos += c; + buf += c; + ret += c; + count -= c; + } + + kfree(dst); + + if (err) + return err; + + return ret; +} + +static ssize_t drm_fb_helper_cfb_write(struct fb_info *info, const char __user *buf, + size_t count, loff_t *ppos) +{ + unsigned long p = *ppos; + u8 *src; + u8 __iomem *dst; + int c, err = 0; + unsigned long total_size; + unsigned long alloc_size; + ssize_t ret = 0; + + if (info->state != FBINFO_STATE_RUNNING) + return -EPERM; + + total_size = info->screen_size; + + if (total_size == 0) + total_size = info->fix.smem_len; + + if (p > total_size) + return -EFBIG; + + if (count > total_size) { + err = -EFBIG; + count = total_size; + } + + if (count + p > total_size) { + /* + * The framebuffer is too small. We do the + * copy operation, but return an error code + * afterwards. Taken from fbdev. + */ + if (!err) + err = -ENOSPC; + count = total_size - p; + } + + alloc_size = min(count, PAGE_SIZE); + + src = kmalloc(alloc_size, GFP_KERNEL); + if (!src) + return -ENOMEM; + + dst = (u8 __iomem *)(info->screen_base + p); + + while (count) { + c = min(count, alloc_size); + + if (copy_from_user(src, buf, c)) { + err = -EFAULT; + break; + } + memcpy_toio(dst, src, c); + + dst += c; + *ppos += c; + buf += c; + ret += c; + count -= c; + } + + kfree(src); + + if (err) + return err; + + return ret; +} + /** * drm_fb_helper_cfb_fillrect - wrapper around cfb_fillrect * @info: fbdev registered by the helper @@ -2027,6 +2156,66 @@ static int drm_fbdev_fb_mmap(struct fb_info *info, struct vm_area_struct *vma) return -ENODEV; } +static ssize_t drm_fbdev_fb_read(struct fb_info *info, char __user *buf, + size_t count, loff_t *ppos) +{ + struct drm_fb_helper *fb_helper = info->par; + struct drm_client_buffer *buffer = fb_helper->buffer; + + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) + return drm_fb_helper_sys_read(info, buf, count, ppos); + else + return drm_fb_helper_cfb_read(info, buf, count, ppos); +} + +static ssize_t drm_fbdev_fb_write(struct fb_info *info, const char __user *buf, + size_t count, loff_t *ppos) +{ + struct drm_fb_helper *fb_helper = info->par; + struct drm_client_buffer *buffer = fb_helper->buffer; + + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) + return drm_fb_helper_sys_write(info, buf, count, ppos); + else + return drm_fb_helper_cfb_write(info, buf, count, ppos); +} + +static void drm_fbdev_fb_fillrect(struct fb_info *info, + const struct fb_fillrect *rect) +{ + struct drm_fb_helper *fb_helper = info->par; + struct drm_client_buffer *buffer = fb_helper->buffer; + + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) + drm_fb_helper_sys_fillrect(info, rect); + else + drm_fb_helper_cfb_fillrect(info, rect); +} + +static void drm_fbdev_fb_copyarea(struct fb_info *info, + const struct fb_copyarea *area) +{ + struct drm_fb_helper *fb_helper = info->par; + struct drm_client_buffer *buffer = fb_helper->buffer; + + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) + drm_fb_helper_sys_copyarea(info, area); + else + drm_fb_helper_cfb_copyarea(info, area); +} + +static void drm_fbdev_fb_imageblit(struct fb_info *info, + const struct fb_image *image) +{ + struct drm_fb_helper *fb_helper = info->par; + struct drm_client_buffer *buffer = fb_helper->buffer; + + if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem) + drm_fb_helper_sys_imageblit(info, image); + else + drm_fb_helper_cfb_imageblit(info, image); +} + static const struct fb_ops drm_fbdev_fb_ops = { .owner = THIS_MODULE, DRM_FB_HELPER_DEFAULT_OPS, @@ -2034,11 +2223,11 @@ static const struct fb_ops drm_fbdev_fb_ops = { .fb_release = drm_fbdev_fb_release, .fb_destroy = drm_fbdev_fb_destroy, .fb_mmap = drm_fbdev_fb_mmap, - .fb_read = drm_fb_helper_sys_read, - .fb_write = drm_fb_helper_sys_write, - .fb_fillrect = drm_fb_helper_sys_fillrect, - .fb_copyarea = drm_fb_helper_sys_copyarea, - .fb_imageblit = drm_fb_helper_sys_imageblit, + .fb_read = drm_fbdev_fb_read, + .fb_write = drm_fbdev_fb_write, + .fb_fillrect = drm_fbdev_fb_fillrect, + .fb_copyarea = drm_fbdev_fb_copyarea, + .fb_imageblit = drm_fbdev_fb_imageblit, }; static struct fb_deferred_io drm_fbdev_defio = { diff --git a/include/drm/drm_mode_config.h b/include/drm/drm_mode_config.h index 5ffbb4ed5b35..ab424ddd7665 100644 --- a/include/drm/drm_mode_config.h +++ b/include/drm/drm_mode_config.h @@ -877,18 +877,6 @@ struct drm_mode_config { */ bool prefer_shadow_fbdev; - /** - * @fbdev_use_iomem: - * - * Set to true if framebuffer reside in iomem. - * When set to true memcpy_toio() is used when copying the framebuffer in - * drm_fb_helper.drm_fb_helper_dirty_blit_real(). - * - * FIXME: This should be replaced with a per-mapping is_iomem - * flag (like ttm does), and then used everywhere in fbdev code. - */ - bool fbdev_use_iomem; - /** * @quirk_addfb_prefer_xbgr_30bpp: *
At least sparc64 requires I/O-specific access to framebuffers. This patch updates the fbdev console accordingly. For drivers with direct access to the framebuffer memory, the callback functions in struct fb_ops test for the type of memory and call the rsp fb_sys_ of fb_cfb_ functions. For drivers that employ a shadow buffer, fbdev's blit function retrieves the framebuffer address as struct dma_buf_map, and uses dma_buf_map interfaces to access the buffer. The bochs driver on sparc64 uses a workaround to flag the framebuffer as I/O memory and avoid a HW exception. With the introduction of struct dma_buf_map, this is not required any longer. The patch removes the rsp code from both, bochs and fbdev. v4: * move dma_buf_map changes into separate patch (Daniel) * TODO list: comment on fbdev updates (Daniel) Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> --- Documentation/gpu/todo.rst | 19 ++- drivers/gpu/drm/bochs/bochs_kms.c | 1 - drivers/gpu/drm/drm_fb_helper.c | 217 ++++++++++++++++++++++++++++-- include/drm/drm_mode_config.h | 12 -- 4 files changed, 220 insertions(+), 29 deletions(-)