From c4d3ae6852bd9f024611d2e8722736ca553e1e43 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Fri, 6 Jan 2017 15:20:09 +0000 Subject: [PATCH] drm/i915: Consolidate checks for memcpy-from-wc support MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit In order to silence sparse: ../drivers/gpu/drm/i915/i915_gpu_error.c:200:39: warning: Using plain integer as NULL pointer add a helper to check whether we have sse4.1 and that the desired alignment is valid for acceleration. v2: Explain the macros and split the two use cases between i915_has_memcpy_from_wc() and i915_can_memcpy_from_wc(). Reported-by: Ville Syrjälä Signed-off-by: Chris Wilson Cc: Ville Syrjälä Reviewed-by: Tvrtko Ursulin Link: http://patchwork.freedesktop.org/patch/msgid/20170106152013.24684-1-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/i915_cmd_parser.c | 2 +- drivers/gpu/drm/i915/i915_drv.h | 16 ++++++++++++++++ drivers/gpu/drm/i915/i915_gpu_error.c | 2 +- drivers/gpu/drm/i915/i915_guc_submission.c | 2 +- 4 files changed, 19 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_cmd_parser.c b/drivers/gpu/drm/i915/i915_cmd_parser.c index 6c310a8..21b1cd9 100644 --- a/drivers/gpu/drm/i915/i915_cmd_parser.c +++ b/drivers/gpu/drm/i915/i915_cmd_parser.c @@ -1079,7 +1079,7 @@ static u32 *copy_batch(struct drm_i915_gem_object *dst_obj, src = ERR_PTR(-ENODEV); if (src_needs_clflush && - i915_memcpy_from_wc((void *)(uintptr_t)batch_start_offset, NULL, 0)) { + i915_can_memcpy_from_wc(NULL, batch_start_offset, 0)) { src = i915_gem_object_pin_map(src_obj, I915_MAP_WC); if (!IS_ERR(src)) { i915_memcpy_from_wc(dst, diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index 239a120..ce051a5 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -4021,6 +4021,22 @@ __i915_request_irq_complete(struct drm_i915_gem_request *req) void i915_memcpy_init_early(struct drm_i915_private *dev_priv); bool i915_memcpy_from_wc(void *dst, const void *src, unsigned long len); +/* The movntdqa instructions used for memcpy-from-wc require 16-byte alignment, + * as well as SSE4.1 support. i915_memcpy_from_wc() will report if it cannot + * perform the operation. To check beforehand, pass in the parameters to + * to i915_can_memcpy_from_wc() - since we only care about the low 4 bits, + * you only need to pass in the minor offsets, page-aligned pointers are + * always valid. + * + * For just checking for SSE4.1, in the foreknowledge that the future use + * will be correctly aligned, just use i915_has_memcpy_from_wc(). + */ +#define i915_can_memcpy_from_wc(dst, src, len) \ + i915_memcpy_from_wc((void *)((unsigned long)(dst) | (unsigned long)(src) | (len)), NULL, 0) + +#define i915_has_memcpy_from_wc() \ + i915_memcpy_from_wc(NULL, NULL, 0) + /* i915_mm.c */ int remap_io_mapping(struct vm_area_struct *vma, unsigned long addr, unsigned long pfn, unsigned long size, diff --git a/drivers/gpu/drm/i915/i915_gpu_error.c b/drivers/gpu/drm/i915/i915_gpu_error.c index e34532d..396c6f0 100644 --- a/drivers/gpu/drm/i915/i915_gpu_error.c +++ b/drivers/gpu/drm/i915/i915_gpu_error.c @@ -197,7 +197,7 @@ static bool compress_init(struct compress *c) } c->tmp = NULL; - if (i915_memcpy_from_wc(NULL, 0, 0)) + if (i915_has_memcpy_from_wc()) c->tmp = (void *)__get_free_page(GFP_ATOMIC | __GFP_NOWARN); return true; diff --git a/drivers/gpu/drm/i915/i915_guc_submission.c b/drivers/gpu/drm/i915/i915_guc_submission.c index 30e012b..710fbb9 100644 --- a/drivers/gpu/drm/i915/i915_guc_submission.c +++ b/drivers/gpu/drm/i915/i915_guc_submission.c @@ -1197,7 +1197,7 @@ static void guc_log_create(struct intel_guc *guc) * it should be present on the chipsets supporting GuC based * submisssions. */ - if (WARN_ON(!i915_memcpy_from_wc(NULL, NULL, 0))) { + if (WARN_ON(!i915_has_memcpy_from_wc())) { /* logging will not be enabled */ i915.guc_log_level = -1; return; -- 2.7.4