Attachment 107830 Details for Bug 79053 – sna/kgem: Gen8 needs blt destination aligned with 32

[patch] sna/kgem: Gen8 needs blt destination aligned with 32

0001-sna-kgem-Gen8-needs-blt-destination-aligned-with-32.patch (text/plain), 1.20 KB, created by Mika Kuoppala on 2014-10-14 16:45:11 UTC

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Creator: Mika Kuoppala

Created: 2014-10-14 16:45:11 UTC

Size: 1.20 KB

patch

obsolete

>From f5d7e974cee28e536c86192b5c9707314cced4e5 Mon Sep 17 00:00:00 2001
>From: Mika Kuoppala <mika.kuoppala@intel.com>
>Date: Tue, 14 Oct 2014 18:26:39 +0300
>Subject: [PATCH] sna/kgem: Gen8 needs blt destination aligned with 32
>
>If the proxy offset for destination relocation is not
>aligned with 32, the XY_SRC_COPY_BLT fail to copy properly
>and will write in to the same cacheline as destination,
>possibly corrupting memory before it.
>
>The exact reason is unknown but broken hw is suspect.
>
>v2: do align check in more proper place (Chris Wilson)
>
>Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=79053
>Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
>---
> src/sna/kgem.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
>diff --git a/src/sna/kgem.c b/src/sna/kgem.c
>index 548ea38..1104cb8 100644
>--- a/src/sna/kgem.c
>+++ b/src/sna/kgem.c
>@@ -6100,6 +6100,10 @@ struct kgem_bo *kgem_create_map(struct kgem *kgem,
> 	first_page = (uintptr_t)ptr;
> 	last_page = first_page + size + PAGE_SIZE - 1;
> 
>+	/* Gen8 blt dst alignment needs to be 32, hw buggy? */
>+	if (kgem->gen >= 0100 && first_page & 0x1f)
>+		return NULL;
>+
> 	first_page &= ~(PAGE_SIZE-1);
> 	last_page &= ~(PAGE_SIZE-1);
> 	assert(last_page > first_page);
>-- 
>1.9.1
>

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Attachments on bug 79053: 99556 | 99571 | 99603 | 100509 | 100511 | 106166 | 106169 | 106170 | 107830 | 109634 | 109657

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