[PATCH v3 7/7] drm/kmb: Enable support for framebuffer console

[Chrisanthus, Anitha]

Hi Thomas,
Thanks for your review.

> -----Original Message-----
> From: Thomas Zimmermann <tzimmermann at suse.de>
> Sent: Thursday, October 14, 2021 6:08 AM
> To: Chrisanthus, Anitha <anitha.chrisanthus at intel.com>; dri-
> devel at lists.freedesktop.org
> Cc: sam at ravnborg.org; Dea, Edmund J <edmund.j.dea at intel.com>
> Subject: Re: [PATCH v3 7/7] drm/kmb: Enable support for framebuffer console
> 
> Hi
> 
> Am 14.10.21 um 01:36 schrieb Anitha Chrisanthus:
> > Enable support for fbcon (framebuffer console).
> > The user can initialize fbcon by loading kmb-drm with the parameter
> > console=1.
> >
> > v2: added missing static clk_enable
> >
> > Signed-off-by: Edmund Dea <edmund.j.dea at intel.com>
> > Signed-off-by: Anitha Chrisanthus <anitha.chrisanthus at intel.com>
> > ---
> >   drivers/gpu/drm/kmb/kmb_drv.c | 11 +++++++++++
> >   1 file changed, 11 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/kmb/kmb_drv.c
> b/drivers/gpu/drm/kmb/kmb_drv.c
> > index 961ac6fb5fcf..b4e66eac63b5 100644
> > --- a/drivers/gpu/drm/kmb/kmb_drv.c
> > +++ b/drivers/gpu/drm/kmb/kmb_drv.c
> > @@ -5,6 +5,7 @@
> >
> >   #include <linux/clk.h>
> >   #include <linux/module.h>
> > +#include <linux/moduleparam.h>
> >   #include <linux/of_graph.h>
> >   #include <linux/of_platform.h>
> >   #include <linux/of_reserved_mem.h>
> > @@ -15,6 +16,7 @@
> >
> >   #include <drm/drm_atomic_helper.h>
> >   #include <drm/drm_drv.h>
> > +#include <drm/drm_fb_helper.h>
> >   #include <drm/drm_gem_cma_helper.h>
> >   #include <drm/drm_gem_framebuffer_helper.h>
> >   #include <drm/drm_probe_helper.h>
> > @@ -24,6 +26,12 @@
> >   #include "kmb_dsi.h"
> >   #include "kmb_regs.h"
> >
> > +/* Module Parameters */
> > +static bool console;
> > +module_param(console, bool, 0400);
> > +MODULE_PARM_DESC(console,
> > +		 "Enable framebuffer console support (0=disable [default],
> 1=on)");
> > +
> >   static int kmb_display_clk_enable(struct kmb_drm_private *kmb)
> >   {
> >   	int ret = 0;
> > @@ -559,6 +567,9 @@ static int kmb_probe(struct platform_device *pdev)
> >   	if (ret)
> >   		goto err_register;
> >
> > +	if (console)
> > +		drm_fbdev_generic_setup(&kmb->drm, 32);
> 
> The use of the final parameter is somewhat confusing and should probably
> be 0. It's the number of bits per pixel. 32 is the default. But the
> preferred way of selecting color mode is via
> dev->mode_config.preferred_depth, which is the color depth (24!). So
> maybe rather set preferred_depth to 24 and let the fbdev helper figure
> out the details.
Will change it in v4.
> 
> Best regards
> Thomas
> 
> > +
> >   	return 0;
> >
> >    err_register:
> >
> 
> --
> Thomas Zimmermann
> Graphics Driver Developer
> SUSE Software Solutions Germany GmbH
> Maxfeldstr. 5, 90409 Nürnberg, Germany
> (HRB 36809, AG Nürnberg)
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