From mboxrd@z Thu Jan 1 00:00:00 1970 From: daeinki Date: Wed, 22 Jun 2011 04:26:04 +0000 Subject: Some questions about DRM(Direct Rendering Manager) Message-Id: <4E016EDC.30200@samsung.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-arm-kernel@lists.infradead.org Hi all, I'm writing Samsung SoC based DRM framework and this one includes FIMD and HDMI driver as hardware dependent modules. and for now, encoder, connector, crtc and fb module has been materialized almost. but I'm contending with framebuffer setting issue(created fb_info should be registered to linux framebuffer through register_framebuffer() or not)as default framebuffer at booting time. at drm_fb_helper_single_fb_probe() of drm_fb_helper.c file, fb_helper's fb_probe callback is called and this one creates new framebuffer and returns a value more then 0 if true. internally, this process creates an fb_info object and drm_framebuffer and then drm_framebuffer would be added to mode_config.fb_list of the drm_device. a value returned, new_fb is used to decide that it calls register_framebuffer() or drm_fb_helper_set_par(). at this point, I am confused it's a good way to call register_framebuffer() otherwise drm_fb_helper_set_par(). if register_framebuffer() is called then I guess drm_fb_helper_set_par() or drm_crtc_helper_set_config() should be called somewhere subsequently to apply this one to real hardware because previous process is just for maintaining data logically.(not set up data to h/w) it's a right way to call register_framebuffer() and then drm_fb_helper_set_par() or drm_crtc_helper_set_config()? otherwise just only drm_fb_helper_set_par() or drm_crtc_helper_set_config() ignoring register_framebuffer()? and what is the purpose of using register_framebuffer()? In my case, first, register_framebuffer() is called and then if desired default crtc id is matched with drm_fb_helper->crtc_info[0 ~ n].crtc_id, it gets mode_set of drm_fb_helper->crtc_info[n] and then it calls drm_crtc_helper_set_config(mode_set). at this time, all the hardware configurations would be completed. thank you in advance. Best Regards Inki Dae. From mboxrd@z Thu Jan 1 00:00:00 1970 From: inki.dae@samsung.com (daeinki) Date: Wed, 22 Jun 2011 13:26:04 +0900 Subject: Some questions about DRM(Direct Rendering Manager) Message-ID: <4E016EDC.30200@samsung.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi all, I'm writing Samsung SoC based DRM framework and this one includes FIMD and HDMI driver as hardware dependent modules. and for now, encoder, connector, crtc and fb module has been materialized almost. but I'm contending with framebuffer setting issue(created fb_info should be registered to linux framebuffer through register_framebuffer() or not)as default framebuffer at booting time. at drm_fb_helper_single_fb_probe() of drm_fb_helper.c file, fb_helper's fb_probe callback is called and this one creates new framebuffer and returns a value more then 0 if true. internally, this process creates an fb_info object and drm_framebuffer and then drm_framebuffer would be added to mode_config.fb_list of the drm_device. a value returned, new_fb is used to decide that it calls register_framebuffer() or drm_fb_helper_set_par(). at this point, I am confused it's a good way to call register_framebuffer() otherwise drm_fb_helper_set_par(). if register_framebuffer() is called then I guess drm_fb_helper_set_par() or drm_crtc_helper_set_config() should be called somewhere subsequently to apply this one to real hardware because previous process is just for maintaining data logically.(not set up data to h/w) it's a right way to call register_framebuffer() and then drm_fb_helper_set_par() or drm_crtc_helper_set_config()? otherwise just only drm_fb_helper_set_par() or drm_crtc_helper_set_config() ignoring register_framebuffer()? and what is the purpose of using register_framebuffer()? In my case, first, register_framebuffer() is called and then if desired default crtc id is matched with drm_fb_helper->crtc_info[0 ~ n].crtc_id, it gets mode_set of drm_fb_helper->crtc_info[n] and then it calls drm_crtc_helper_set_config(mode_set). at this time, all the hardware configurations would be completed. thank you in advance. Best Regards Inki Dae.