This is a note to let you know that I've just added the patch titled drm/i915: Don't clobber the GTT when it's within stolen memory to the 3.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: drm-i915-don-t-clobber-the-gtt-when-it-s-within-stolen-memory.patch and it can be found in the queue-3.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From f1e1c2129b79cfdaf07bca37c5a10569fe021abe Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= <ville.syrjala@xxxxxxxxxxxxxxx> Date: Thu, 5 Jun 2014 20:02:59 +0300 Subject: drm/i915: Don't clobber the GTT when it's within stolen memory MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> commit f1e1c2129b79cfdaf07bca37c5a10569fe021abe upstream. On most gen2-4 platforms the GTT can be (or maybe always is?) inside the stolen memory region. If that's the case, reduce the size of the stolen memory appropriately to make make sure we don't clobber the GTT. v2: Deal with gen4 36 bit physical address Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=80151 Acked-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> Signed-off-by: Daniel Vetter <daniel.vetter@xxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/i915/i915_gem_stolen.c | 44 +++++++++++++++++++++++++++++++++ drivers/gpu/drm/i915/i915_reg.h | 3 ++ 2 files changed, 47 insertions(+) --- a/drivers/gpu/drm/i915/i915_gem_stolen.c +++ b/drivers/gpu/drm/i915/i915_gem_stolen.c @@ -74,6 +74,50 @@ static unsigned long i915_stolen_to_phys if (base == 0) return 0; + /* make sure we don't clobber the GTT if it's within stolen memory */ + if (INTEL_INFO(dev)->gen <= 4 && !IS_G33(dev) && !IS_G4X(dev)) { + struct { + u32 start, end; + } stolen[2] = { + { .start = base, .end = base + dev_priv->gtt.stolen_size, }, + { .start = base, .end = base + dev_priv->gtt.stolen_size, }, + }; + u64 gtt_start, gtt_end; + + gtt_start = I915_READ(PGTBL_CTL); + if (IS_GEN4(dev)) + gtt_start = (gtt_start & PGTBL_ADDRESS_LO_MASK) | + (gtt_start & PGTBL_ADDRESS_HI_MASK) << 28; + else + gtt_start &= PGTBL_ADDRESS_LO_MASK; + gtt_end = gtt_start + gtt_total_entries(dev_priv->gtt) * 4; + + if (gtt_start >= stolen[0].start && gtt_start < stolen[0].end) + stolen[0].end = gtt_start; + if (gtt_end > stolen[1].start && gtt_end <= stolen[1].end) + stolen[1].start = gtt_end; + + /* pick the larger of the two chunks */ + if (stolen[0].end - stolen[0].start > + stolen[1].end - stolen[1].start) { + base = stolen[0].start; + dev_priv->gtt.stolen_size = stolen[0].end - stolen[0].start; + } else { + base = stolen[1].start; + dev_priv->gtt.stolen_size = stolen[1].end - stolen[1].start; + } + + if (stolen[0].start != stolen[1].start || + stolen[0].end != stolen[1].end) { + DRM_DEBUG_KMS("GTT within stolen memory at 0x%llx-0x%llx\n", + (unsigned long long) gtt_start, + (unsigned long long) gtt_end - 1); + DRM_DEBUG_KMS("Stolen memory adjusted to 0x%x-0x%x\n", + base, base + (u32) dev_priv->gtt.stolen_size - 1); + } + } + + /* Verify that nothing else uses this physical address. Stolen * memory should be reserved by the BIOS and hidden from the * kernel. So if the region is already marked as busy, something --- a/drivers/gpu/drm/i915/i915_reg.h +++ b/drivers/gpu/drm/i915/i915_reg.h @@ -659,6 +659,9 @@ enum punit_power_well { /* * Instruction and interrupt control regs */ +#define PGTBL_CTL 0x02020 +#define PGTBL_ADDRESS_LO_MASK 0xfffff000 /* bits [31:12] */ +#define PGTBL_ADDRESS_HI_MASK 0x000000f0 /* bits [35:32] (gen4) */ #define PGTBL_ER 0x02024 #define RENDER_RING_BASE 0x02000 #define BSD_RING_BASE 0x04000 Patches currently in stable-queue which might be from ville.syrjala@xxxxxxxxxxxxxxx are queue-3.15/drm-i915-don-t-clobber-the-gtt-when-it-s-within-stolen-memory.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html