Re: [PATCH v4 10/10] drm/fb_helper: Support framebuffers in I/O memory
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 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 > > > > 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 > > > > > --- > > > 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 , 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) > > >
Re: [PATCH v4 10/10] drm/fb_helper: Support framebuffers in I/O memory
Hi On Fri, 16 Oct 2020 14:03:47 +0200 Sam Ravnborg 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 > > 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 > > > --- > > 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 , 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 = _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) > > +
Re: [PATCH v4 10/10] drm/fb_helper: Support framebuffers in I/O memory
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
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
> ---
> 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 , 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 = _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;
Re: [PATCH v4 10/10] drm/fb_helper: Support framebuffers in I/O memory
Hi
On Fri, 16 Oct 2020 12:58:54 +0200 Sam Ravnborg 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
It has not been brought up yet. See below.
>
>
> > Signed-off-by: Thomas Zimmermann
> > ---
> > 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 , 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 = _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)
> > -
Re: [PATCH v4 10/10] drm/fb_helper: Support framebuffers in I/O memory
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
> Signed-off-by: Thomas Zimmermann
> ---
> 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 , 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 = _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++) {
> +
[PATCH v4 10/10] drm/fb_helper: Support framebuffers in I/O memory
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
---
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 , 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 = _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, );
if (ret)
return;
- drm_fb_helper_dirty_blit_real(helper, _copy);
+
