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path: root/drivers/gpu/drm/i915/i915_memcpy.c
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Diffstat (limited to 'drivers/gpu/drm/i915/i915_memcpy.c')
-rw-r--r--drivers/gpu/drm/i915/i915_memcpy.c75
1 files changed, 71 insertions, 4 deletions
diff --git a/drivers/gpu/drm/i915/i915_memcpy.c b/drivers/gpu/drm/i915/i915_memcpy.c
index 07b04b0acb77..fdd550405fd3 100644
--- a/drivers/gpu/drm/i915/i915_memcpy.c
+++ b/drivers/gpu/drm/i915/i915_memcpy.c
@@ -27,6 +27,12 @@
#include "i915_memcpy.h"
+#if IS_ENABLED(CONFIG_DRM_I915_DEBUG)
+#define CI_BUG_ON(expr) BUG_ON(expr)
+#else
+#define CI_BUG_ON(expr) BUILD_BUG_ON_INVALID(expr)
+#endif
+
static DEFINE_STATIC_KEY_FALSE(has_movntdqa);
#ifdef CONFIG_AS_MOVNTDQA
@@ -34,7 +40,6 @@ static void __memcpy_ntdqa(void *dst, const void *src, unsigned long len)
{
kernel_fpu_begin();
- len >>= 4;
while (len >= 4) {
asm("movntdqa (%0), %%xmm0\n"
"movntdqa 16(%0), %%xmm1\n"
@@ -59,6 +64,38 @@ static void __memcpy_ntdqa(void *dst, const void *src, unsigned long len)
kernel_fpu_end();
}
+
+static void __memcpy_ntdqu(void *dst, const void *src, unsigned long len)
+{
+ kernel_fpu_begin();
+
+ while (len >= 4) {
+ asm("movntdqa (%0), %%xmm0\n"
+ "movntdqa 16(%0), %%xmm1\n"
+ "movntdqa 32(%0), %%xmm2\n"
+ "movntdqa 48(%0), %%xmm3\n"
+ "movups %%xmm0, (%1)\n"
+ "movups %%xmm1, 16(%1)\n"
+ "movups %%xmm2, 32(%1)\n"
+ "movups %%xmm3, 48(%1)\n"
+ :: "r" (src), "r" (dst) : "memory");
+ src += 64;
+ dst += 64;
+ len -= 4;
+ }
+ while (len--) {
+ asm("movntdqa (%0), %%xmm0\n"
+ "movups %%xmm0, (%1)\n"
+ :: "r" (src), "r" (dst) : "memory");
+ src += 16;
+ dst += 16;
+ }
+
+ kernel_fpu_end();
+}
+#else
+static void __memcpy_ntdqa(void *dst, const void *src, unsigned long len) {}
+static void __memcpy_ntdqu(void *dst, const void *src, unsigned long len) {}
#endif
/**
@@ -83,17 +120,47 @@ bool i915_memcpy_from_wc(void *dst, const void *src, unsigned long len)
if (unlikely(((unsigned long)dst | (unsigned long)src | len) & 15))
return false;
-#ifdef CONFIG_AS_MOVNTDQA
if (static_branch_likely(&has_movntdqa)) {
if (likely(len))
- __memcpy_ntdqa(dst, src, len);
+ __memcpy_ntdqa(dst, src, len >> 4);
return true;
}
-#endif
return false;
}
+/**
+ * i915_unaligned_memcpy_from_wc: perform a mostly accelerated read from WC
+ * @dst: destination pointer
+ * @src: source pointer
+ * @len: how many bytes to copy
+ *
+ * Like i915_memcpy_from_wc(), the unaligned variant copies @len bytes from
+ * @src to @dst using * non-temporal instructions where available, but
+ * accepts that its arguments may not be aligned, but are valid for the
+ * potential 16-byte read past the end.
+ */
+void i915_unaligned_memcpy_from_wc(void *dst, void *src, unsigned long len)
+{
+ unsigned long addr;
+
+ CI_BUG_ON(!i915_has_memcpy_from_wc());
+
+ addr = (unsigned long)src;
+ if (!IS_ALIGNED(addr, 16)) {
+ unsigned long x = min(ALIGN(addr, 16) - addr, len);
+
+ memcpy(dst, src, x);
+
+ len -= x;
+ dst += x;
+ src += x;
+ }
+
+ if (likely(len))
+ __memcpy_ntdqu(dst, src, DIV_ROUND_UP(len, 16));
+}
+
void i915_memcpy_init_early(struct drm_i915_private *dev_priv)
{
/*