On 04/02/16 09:30, ankitprasad.r.sharma@xxxxxxxxx wrote:
From: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> Introduced a new vm specfic callback insert_page() to program a single pte in ggtt or ppgtt. This allows us to map a single page in to the mappable aperture space. This can be iterated over to access the whole object by using space as meagre as page size. v2: Added low level rpm assertions to insert_page routines (Chris) Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> Signed-off-by: Ankitprasad Sharma <ankitprasad.r.sharma@xxxxxxxxx> --- drivers/char/agp/intel-gtt.c | 9 +++++ drivers/gpu/drm/i915/i915_gem_gtt.c | 65 +++++++++++++++++++++++++++++++++++++ drivers/gpu/drm/i915/i915_gem_gtt.h | 5 +++ include/drm/intel-gtt.h | 3 ++ 4 files changed, 82 insertions(+) diff --git a/drivers/char/agp/intel-gtt.c b/drivers/char/agp/intel-gtt.c index 1341a94..7c68576 100644 --- a/drivers/char/agp/intel-gtt.c +++ b/drivers/char/agp/intel-gtt.c @@ -838,6 +838,15 @@ static bool i830_check_flags(unsigned int flags) return false; } +void intel_gtt_insert_page(dma_addr_t addr, + unsigned int pg, + unsigned int flags) +{ + intel_private.driver->write_entry(addr, pg, flags); + wmb(); +} +EXPORT_SYMBOL(intel_gtt_insert_page); + void intel_gtt_insert_sg_entries(struct sg_table *st, unsigned int pg_start, unsigned int flags) diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c index 715a771..a64018f 100644 --- a/drivers/gpu/drm/i915/i915_gem_gtt.c +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c @@ -2341,6 +2341,28 @@ static void gen8_set_pte(void __iomem *addr, gen8_pte_t pte) #endif } +static void gen8_ggtt_insert_page(struct i915_address_space *vm, + dma_addr_t addr, + uint64_t offset, + enum i915_cache_level level, + u32 unused) +{ + struct drm_i915_private *dev_priv = to_i915(vm->dev); + gen8_pte_t __iomem *pte = + (gen8_pte_t __iomem *)dev_priv->gtt.gsm + + (offset >> PAGE_SHIFT); + int rpm_atomic_seq; + + rpm_atomic_seq = assert_rpm_atomic_begin(dev_priv); + + gen8_set_pte(pte, gen8_pte_encode(addr, level, true)); + wmb();
gen8_ggtt_insert_entries does a read-back of the PTE after having written it with a big fat comment talking about how that could be really important. This is not needed in this path?
+ + I915_WRITE(GFX_FLSH_CNTL_GEN6, GFX_FLSH_CNTL_EN);
Why is the posting read not required here as in gen8_ggtt_insert_entries?
+ + assert_rpm_atomic_end(dev_priv, rpm_atomic_seq); +} + static void gen8_ggtt_insert_entries(struct i915_address_space *vm, struct sg_table *st, uint64_t start, @@ -2412,6 +2434,28 @@ static void gen8_ggtt_insert_entries__BKL(struct i915_address_space *vm, stop_machine(gen8_ggtt_insert_entries__cb, &arg, NULL); } +static void gen6_ggtt_insert_page(struct i915_address_space *vm, + dma_addr_t addr, + uint64_t offset, + enum i915_cache_level level, + u32 flags) +{ + struct drm_i915_private *dev_priv = to_i915(vm->dev); + gen6_pte_t __iomem *pte = + (gen6_pte_t __iomem *)dev_priv->gtt.gsm + + (offset >> PAGE_SHIFT); + int rpm_atomic_seq; + + rpm_atomic_seq = assert_rpm_atomic_begin(dev_priv); + + iowrite32(vm->pte_encode(addr, level, true, flags), pte); + wmb(); + + I915_WRITE(GFX_FLSH_CNTL_GEN6, GFX_FLSH_CNTL_EN); + + assert_rpm_atomic_end(dev_priv, rpm_atomic_seq); +}
Same questions as for the gen8 version. Regards, Tvrtko _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx