Re: [PATCH v5 10/10] drm/fb_helper: Support framebuffers in I/O memory
Hi
Am 24.10.20 um 22:38 schrieb Sam Ravnborg:
> Hi Thomas.
>
> On Tue, Oct 20, 2020 at 02:20:46PM +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. Read and write operations are implemented
>> internally by DRM's fbdev helper.
>>
>> 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.
>>
>> v5:
>> * implement fb_read/fb_write internally (Daniel, Sam)
>> v4:
>> * move dma_buf_map changes into separate patch (Daniel)
>> * TODO list: comment on fbdev updates (Daniel)
>>
>> Signed-off-by: Thomas Zimmermann
>> Tested-by: Sam Ravnborg
> Reviewed-by: Sam Ravnborg
>
> But see a few comments below on naming for you to consider.
>
> Sam
>
>> ---
>> Documentation/gpu/todo.rst| 19 ++-
>> drivers/gpu/drm/bochs/bochs_kms.c | 1 -
>> drivers/gpu/drm/drm_fb_helper.c | 227 --
>> include/drm/drm_mode_config.h | 12 --
>> 4 files changed, 230 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..1d3180841778 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);
>> +
Re: [PATCH v5 10/10] drm/fb_helper: Support framebuffers in I/O memory
Hi Thomas.
On Tue, Oct 20, 2020 at 02:20:46PM +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. Read and write operations are implemented
> internally by DRM's fbdev helper.
>
> 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.
>
> v5:
> * implement fb_read/fb_write internally (Daniel, Sam)
> v4:
> * move dma_buf_map changes into separate patch (Daniel)
> * TODO list: comment on fbdev updates (Daniel)
>
> Signed-off-by: Thomas Zimmermann
> Tested-by: Sam Ravnborg
Reviewed-by: Sam Ravnborg
But see a few comments below on naming for you to consider.
Sam
> ---
> Documentation/gpu/todo.rst| 19 ++-
> drivers/gpu/drm/bochs/bochs_kms.c | 1 -
> drivers/gpu/drm/drm_fb_helper.c | 227 --
> include/drm/drm_mode_config.h | 12 --
> 4 files changed, 230 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..1d3180841778 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++) {
> +
Re: [PATCH v5 10/10] drm/fb_helper: Support framebuffers in I/O memory
On Thu, Oct 22, 2020 at 10:37:56AM +0200, Thomas Zimmermann wrote:
> Hi
>
> On 22.10.20 10:05, Daniel Vetter wrote:
> > On Tue, Oct 20, 2020 at 02:20:46PM +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. Read and write operations are implemented
> >> internally by DRM's fbdev helper.
> >>
> >> 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.
> >>
> >> v5:
> >>* implement fb_read/fb_write internally (Daniel, Sam)
> >> v4:
> >>* move dma_buf_map changes into separate patch (Daniel)
> >>* TODO list: comment on fbdev updates (Daniel)
> >>
> >> Signed-off-by: Thomas Zimmermann
> >> Tested-by: Sam Ravnborg
> >> ---
> >> Documentation/gpu/todo.rst| 19 ++-
> >> drivers/gpu/drm/bochs/bochs_kms.c | 1 -
> >> drivers/gpu/drm/drm_fb_helper.c | 227 --
> >> include/drm/drm_mode_config.h | 12 --
> >> 4 files changed, 230 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..1d3180841778 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 v5 10/10] drm/fb_helper: Support framebuffers in I/O memory
Hi
On 22.10.20 10:05, Daniel Vetter wrote:
> On Tue, Oct 20, 2020 at 02:20:46PM +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. Read and write operations are implemented
>> internally by DRM's fbdev helper.
>>
>> 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.
>>
>> v5:
>> * implement fb_read/fb_write internally (Daniel, Sam)
>> v4:
>> * move dma_buf_map changes into separate patch (Daniel)
>> * TODO list: comment on fbdev updates (Daniel)
>>
>> Signed-off-by: Thomas Zimmermann
>> Tested-by: Sam Ravnborg
>> ---
>> Documentation/gpu/todo.rst| 19 ++-
>> drivers/gpu/drm/bochs/bochs_kms.c | 1 -
>> drivers/gpu/drm/drm_fb_helper.c | 227 --
>> include/drm/drm_mode_config.h | 12 --
>> 4 files changed, 230 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..1d3180841778 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++) {
>>
Re: [PATCH v5 10/10] drm/fb_helper: Support framebuffers in I/O memory
On Tue, Oct 20, 2020 at 02:20:46PM +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. Read and write operations are implemented
> internally by DRM's fbdev helper.
>
> 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.
>
> v5:
> * implement fb_read/fb_write internally (Daniel, Sam)
> v4:
> * move dma_buf_map changes into separate patch (Daniel)
> * TODO list: comment on fbdev updates (Daniel)
>
> Signed-off-by: Thomas Zimmermann
> Tested-by: Sam Ravnborg
> ---
> Documentation/gpu/todo.rst| 19 ++-
> drivers/gpu/drm/bochs/bochs_kms.c | 1 -
> drivers/gpu/drm/drm_fb_helper.c | 227 --
> include/drm/drm_mode_config.h | 12 --
> 4 files changed, 230 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..1d3180841778 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 +=
[PATCH v5 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. Read and write operations are implemented
internally by DRM's fbdev helper.
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.
v5:
* implement fb_read/fb_write internally (Daniel, Sam)
v4:
* move dma_buf_map changes into separate patch (Daniel)
* TODO list: comment on fbdev updates (Daniel)
Signed-off-by: Thomas Zimmermann
Tested-by: Sam Ravnborg
---
Documentation/gpu/todo.rst| 19 ++-
drivers/gpu/drm/bochs/bochs_kms.c | 1 -
drivers/gpu/drm/drm_fb_helper.c | 227 --
include/drm/drm_mode_config.h | 12 --
4 files changed, 230 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..1d3180841778 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, );
