On Mon, 2015-04-27 at 09:43 -0700, Luis R. Rodriguez wrote: > From: "Luis R. Rodriguez" <mcgrof@xxxxxxxx> > > We are burrying direct access to MTRR code support on > x86 in order to take advantage of PAT. In the future we > also want to make the default behaviour of ioremap_nocache() > to use strong UC, use of mtrr_add() on those systems > would make write-combining void. > > In order to help both enable us to later make strong > UC default and in order to phase out direct MTRR access > code port the driver over to arch_phys_wc_add() and > annotate that the device driver requires systems to > boot with PAT disabled, with the nopat kernel parameter. > > This is a worthy comprmise given that the hardware is > really rare these days, and perhaps only some lost souls > in some third world country are expected to be using this > feature of the device driver. > > Cc: Andy Walls <awalls@xxxxxxxxxxxxxxxx> Acked-by: Andy Walls <awalls@xxxxxxxxxxxxxxxx> Regards, Andy > Cc: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxx> > Cc: Andy Lutomirski <luto@xxxxxxxxxxxxxx> > Cc: Suresh Siddha <sbsiddha@xxxxxxxxx> > Cc: Ingo Molnar <mingo@xxxxxxx> > Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> > Cc: Juergen Gross <jgross@xxxxxxxx> > Cc: Daniel Vetter <daniel.vetter@xxxxxxxx> > Cc: Dave Airlie <airlied@xxxxxxxxxx> > Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> > Cc: Antonino Daplas <adaplas@xxxxxxxxx> > Cc: Jean-Christophe Plagniol-Villard <plagnioj@xxxxxxxxxxxx> > Cc: Tomi Valkeinen <tomi.valkeinen@xxxxxx> > Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx> > Cc: Arnd Bergmann <arnd@xxxxxxxx> > Cc: Michael S. Tsirkin <mst@xxxxxxxxxx> > Cc: Stefan Bader <stefan.bader@xxxxxxxxxxxxx> > Cc: Ville Syrjälä <syrjala@xxxxxx> > Cc: Mel Gorman <mgorman@xxxxxxx> > Cc: Vlastimil Babka <vbabka@xxxxxxx> > Cc: Borislav Petkov <bp@xxxxxxx> > Cc: Davidlohr Bueso <dbueso@xxxxxxx> > Cc: konrad.wilk@xxxxxxxxxx > Cc: ville.syrjala@xxxxxxxxxxxxxxx > Cc: david.vrabel@xxxxxxxxxx > Cc: jbeulich@xxxxxxxx > Cc: toshi.kani@xxxxxx > Cc: Roger Pau Monné <roger.pau@xxxxxxxxxx> > Cc: linux-fbdev@xxxxxxxxxxxxxxx > Cc: linux-kernel@xxxxxxxxxxxxxxx > Cc: ivtv-devel@xxxxxxxxxxxxxx > Cc: linux-media@xxxxxxxxxxxxxxx > Cc: xen-devel@xxxxxxxxxxxxxxxxxxx > Signed-off-by: Luis R. Rodriguez <mcgrof@xxxxxxxx> > --- > > This v2 moves the PAT bail out error check on to ivtvfb_init() > as per Andy's request. It also removes some comment about TODO > items for PAT. > > drivers/media/pci/ivtv/Kconfig | 3 +++ > drivers/media/pci/ivtv/ivtvfb.c | 58 ++++++++++++++++------------------------- > 2 files changed, 26 insertions(+), 35 deletions(-) > > diff --git a/drivers/media/pci/ivtv/Kconfig b/drivers/media/pci/ivtv/Kconfig > index dd6ee57e..b2a7f88 100644 > --- a/drivers/media/pci/ivtv/Kconfig > +++ b/drivers/media/pci/ivtv/Kconfig > @@ -57,5 +57,8 @@ config VIDEO_FB_IVTV > This is used in the Hauppauge PVR-350 card. There is a driver > homepage at <http://www.ivtvdriver.org>. > > + If you have this hardware you will need to boot with PAT disabled > + on your x86 systems, use the nopat kernel parameter. > + > To compile this driver as a module, choose M here: the > module will be called ivtvfb. > diff --git a/drivers/media/pci/ivtv/ivtvfb.c b/drivers/media/pci/ivtv/ivtvfb.c > index 9ff1230..8761e3e 100644 > --- a/drivers/media/pci/ivtv/ivtvfb.c > +++ b/drivers/media/pci/ivtv/ivtvfb.c > @@ -44,8 +44,8 @@ > #include <linux/ivtvfb.h> > #include <linux/slab.h> > > -#ifdef CONFIG_MTRR > -#include <asm/mtrr.h> > +#ifdef CONFIG_X86_64 > +#include <asm/pat.h> > #endif > > #include "ivtv-driver.h" > @@ -155,12 +155,11 @@ struct osd_info { > /* Buffer size */ > u32 video_buffer_size; > > -#ifdef CONFIG_MTRR > /* video_base rounded down as required by hardware MTRRs */ > unsigned long fb_start_aligned_physaddr; > /* video_base rounded up as required by hardware MTRRs */ > unsigned long fb_end_aligned_physaddr; > -#endif > + int wc_cookie; > > /* Store the buffer offset */ > int set_osd_coords_x; > @@ -1099,6 +1098,8 @@ static int ivtvfb_init_vidmode(struct ivtv *itv) > static int ivtvfb_init_io(struct ivtv *itv) > { > struct osd_info *oi = itv->osd_info; > + /* Find the largest power of two that maps the whole buffer */ > + int size_shift = 31; > > mutex_lock(&itv->serialize_lock); > if (ivtv_init_on_first_open(itv)) { > @@ -1132,29 +1133,16 @@ static int ivtvfb_init_io(struct ivtv *itv) > oi->video_pbase, oi->video_vbase, > oi->video_buffer_size / 1024); > > -#ifdef CONFIG_MTRR > - { > - /* Find the largest power of two that maps the whole buffer */ > - int size_shift = 31; > - > - while (!(oi->video_buffer_size & (1 << size_shift))) { > - size_shift--; > - } > - size_shift++; > - oi->fb_start_aligned_physaddr = oi->video_pbase & ~((1 << size_shift) - 1); > - oi->fb_end_aligned_physaddr = oi->video_pbase + oi->video_buffer_size; > - oi->fb_end_aligned_physaddr += (1 << size_shift) - 1; > - oi->fb_end_aligned_physaddr &= ~((1 << size_shift) - 1); > - if (mtrr_add(oi->fb_start_aligned_physaddr, > - oi->fb_end_aligned_physaddr - oi->fb_start_aligned_physaddr, > - MTRR_TYPE_WRCOMB, 1) < 0) { > - IVTVFB_INFO("disabled mttr\n"); > - oi->fb_start_aligned_physaddr = 0; > - oi->fb_end_aligned_physaddr = 0; > - } > - } > -#endif > - > + while (!(oi->video_buffer_size & (1 << size_shift))) > + size_shift--; > + size_shift++; > + oi->fb_start_aligned_physaddr = oi->video_pbase & ~((1 << size_shift) - 1); > + oi->fb_end_aligned_physaddr = oi->video_pbase + oi->video_buffer_size; > + oi->fb_end_aligned_physaddr += (1 << size_shift) - 1; > + oi->fb_end_aligned_physaddr &= ~((1 << size_shift) - 1); > + oi->wc_cookie = arch_phys_wc_add(oi->fb_start_aligned_physaddr, > + oi->fb_end_aligned_physaddr - > + oi->fb_start_aligned_physaddr); > /* Blank the entire osd. */ > memset_io(oi->video_vbase, 0, oi->video_buffer_size); > > @@ -1172,14 +1160,7 @@ static void ivtvfb_release_buffers (struct ivtv *itv) > > /* Release pseudo palette */ > kfree(oi->ivtvfb_info.pseudo_palette); > - > -#ifdef CONFIG_MTRR > - if (oi->fb_end_aligned_physaddr) { > - mtrr_del(-1, oi->fb_start_aligned_physaddr, > - oi->fb_end_aligned_physaddr - oi->fb_start_aligned_physaddr); > - } > -#endif > - > + arch_phys_wc_del(oi->wc_cookie); > kfree(oi); > itv->osd_info = NULL; > } > @@ -1284,6 +1265,13 @@ static int __init ivtvfb_init(void) > int registered = 0; > int err; > > +#ifdef CONFIG_X86_64 > + if (WARN(pat_enabled, > + "ivtvfb needs PAT disabled, boot with nopat kernel parameter\n")) { > + return EINVAL; > + } > +#endif > + > if (ivtvfb_card_id < -1 || ivtvfb_card_id >= IVTV_MAX_CARDS) { > printk(KERN_ERR "ivtvfb: ivtvfb_card_id parameter is out of range (valid range: -1 - %d)\n", > IVTV_MAX_CARDS - 1); -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
