Re: [PATCH] drm/i915: flush system agent TLBs on SNB so we can WC map the PTEs

From: Daniel Vetter <daniel@ffwll.ch>
To: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: intel-gfx@lists.freedesktop.org
Subject: Re: [PATCH] drm/i915: flush system agent TLBs on SNB so we can WC map the PTEs
Date: Mon, 22 Oct 2012 14:46:21 +0200	[thread overview]
Message-ID: <20121022124621.GE24005@phenom.ffwll.local> (raw)
In-Reply-To: <20121011103237.21e6637c@jbarnes-desktop>

On Thu, Oct 11, 2012 at 10:32:37AM -0700, Jesse Barnes wrote:
> I've only lightly tested this so far, but the corruption seems to be
> gone if I write the GFX_FLSH_CNTL reg after binding an object.  This
> register should control the TLB for the system agent, which is what CPU
> mapped objects will go through.
> 
> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

Ok, I've pushed out a new dinq with -rc2 backmerged. Can you please
resubmit, with the conflicts resolved and GFX_FLSH_CNTL bikeshedded to
GFX_FLSH_CNTL_GEN6? There's also a _VLV #define variant which needs to be
killed since it's redundant now ...

Thanks, Daniel

> 
> diff --git a/drivers/char/agp/intel-agp.h b/drivers/char/agp/intel-agp.h
> index 6ec0fff..95f0d4d 100644
> --- a/drivers/char/agp/intel-agp.h
> +++ b/drivers/char/agp/intel-agp.h
> @@ -99,6 +99,9 @@
>  #define GFX_FLSH_CNTL		0x2170 /* 915+ */
>  #define GFX_FLSH_CNTL_VLV	0x101008
>  
> +#define GFX_FLSH_CNTL		0x101008
> +#define   GFX_FLSH_CNTL_EN	(1<<0)
> +
>  #define I810_DRAM_CTL		0x3000
>  #define I810_DRAM_ROW_0		0x00000001
>  #define I810_DRAM_ROW_0_SDRAM	0x00000001
> diff --git a/drivers/char/agp/intel-gtt.c b/drivers/char/agp/intel-gtt.c
> index e01f5ea..08844d6 100644
> --- a/drivers/char/agp/intel-gtt.c
> +++ b/drivers/char/agp/intel-gtt.c
> @@ -667,12 +667,8 @@ static int intel_gtt_init(void)
>  	gtt_map_size = intel_private.base.gtt_total_entries * 4;
>  
>  	intel_private.gtt = NULL;
> -	if (INTEL_GTT_GEN < 6)
> -		intel_private.gtt = ioremap_wc(intel_private.gtt_bus_addr,
> -					       gtt_map_size);
> -	if (intel_private.gtt == NULL)
> -		intel_private.gtt = ioremap(intel_private.gtt_bus_addr,
> -					    gtt_map_size);
> +	intel_private.gtt = ioremap_wc(intel_private.gtt_bus_addr,
> +				       gtt_map_size);
>  	if (intel_private.gtt == NULL) {
>  		intel_private.driver->cleanup();
>  		iounmap(intel_private.registers);
> @@ -897,6 +893,7 @@ void intel_gtt_insert_sg_entries(struct sg_table *st,
>  		}
>  	}
>  	readl(intel_private.gtt+j-1);
> +	writel(GFX_FLSH_CNTL_EN, intel_private.registers + GFX_FLSH_CNTL);
>  }
>  EXPORT_SYMBOL(intel_gtt_insert_sg_entries);
>  
> @@ -913,6 +910,7 @@ static void intel_gtt_insert_pages(unsigned int first_entry,
>  						  j, flags);
>  	}
>  	readl(intel_private.gtt+j-1);
> +	writel(GFX_FLSH_CNTL_EN, intel_private.registers + GFX_FLSH_CNTL);
>  }
>  
>  static int intel_fake_agp_insert_entries(struct agp_memory *mem,
> @@ -1256,7 +1254,7 @@ static int i9xx_setup(void)
>  
>  	reg_addr &= 0xfff80000;
>  
> -	if (INTEL_GTT_GEN >= 7)
> +	if (INTEL_GTT_GEN >= 6)
>  		size = MB(2);
>  
>  	intel_private.registers = ioremap(reg_addr, size);
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx@lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/intel-gfx

-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch