v4.19.13 snapshot.
diff --git a/drivers/gpu/drm/drm_cache.c b/drivers/gpu/drm/drm_cache.c
new file mode 100644
index 0000000..3bd76e9
--- /dev/null
+++ b/drivers/gpu/drm/drm_cache.c
@@ -0,0 +1,176 @@
+/**************************************************************************
+ *
+ * Copyright (c) 2006-2007 Tungsten Graphics, Inc., Cedar Park, TX., USA
+ * All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sub license, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the
+ * next paragraph) shall be included in all copies or substantial portions
+ * of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
+ * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+ * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+ * USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ **************************************************************************/
+/*
+ * Authors: Thomas Hellström <thomas-at-tungstengraphics-dot-com>
+ */
+
+#include <linux/export.h>
+#include <linux/highmem.h>
+
+#include <drm/drm_cache.h>
+
+#if defined(CONFIG_X86)
+#include <asm/smp.h>
+
+/*
+ * clflushopt is an unordered instruction which needs fencing with mfence or
+ * sfence to avoid ordering issues. For drm_clflush_page this fencing happens
+ * in the caller.
+ */
+static void
+drm_clflush_page(struct page *page)
+{
+ uint8_t *page_virtual;
+ unsigned int i;
+ const int size = boot_cpu_data.x86_clflush_size;
+
+ if (unlikely(page == NULL))
+ return;
+
+ page_virtual = kmap_atomic(page);
+ for (i = 0; i < PAGE_SIZE; i += size)
+ clflushopt(page_virtual + i);
+ kunmap_atomic(page_virtual);
+}
+
+static void drm_cache_flush_clflush(struct page *pages[],
+ unsigned long num_pages)
+{
+ unsigned long i;
+
+ mb();
+ for (i = 0; i < num_pages; i++)
+ drm_clflush_page(*pages++);
+ mb();
+}
+#endif
+
+/**
+ * drm_clflush_pages - Flush dcache lines of a set of pages.
+ * @pages: List of pages to be flushed.
+ * @num_pages: Number of pages in the array.
+ *
+ * Flush every data cache line entry that points to an address belonging
+ * to a page in the array.
+ */
+void
+drm_clflush_pages(struct page *pages[], unsigned long num_pages)
+{
+
+#if defined(CONFIG_X86)
+ if (static_cpu_has(X86_FEATURE_CLFLUSH)) {
+ drm_cache_flush_clflush(pages, num_pages);
+ return;
+ }
+
+ if (wbinvd_on_all_cpus())
+ pr_err("Timed out waiting for cache flush\n");
+
+#elif defined(__powerpc__)
+ unsigned long i;
+ for (i = 0; i < num_pages; i++) {
+ struct page *page = pages[i];
+ void *page_virtual;
+
+ if (unlikely(page == NULL))
+ continue;
+
+ page_virtual = kmap_atomic(page);
+ flush_dcache_range((unsigned long)page_virtual,
+ (unsigned long)page_virtual + PAGE_SIZE);
+ kunmap_atomic(page_virtual);
+ }
+#else
+ pr_err("Architecture has no drm_cache.c support\n");
+ WARN_ON_ONCE(1);
+#endif
+}
+EXPORT_SYMBOL(drm_clflush_pages);
+
+/**
+ * drm_clflush_sg - Flush dcache lines pointing to a scather-gather.
+ * @st: struct sg_table.
+ *
+ * Flush every data cache line entry that points to an address in the
+ * sg.
+ */
+void
+drm_clflush_sg(struct sg_table *st)
+{
+#if defined(CONFIG_X86)
+ if (static_cpu_has(X86_FEATURE_CLFLUSH)) {
+ struct sg_page_iter sg_iter;
+
+ mb();
+ for_each_sg_page(st->sgl, &sg_iter, st->nents, 0)
+ drm_clflush_page(sg_page_iter_page(&sg_iter));
+ mb();
+
+ return;
+ }
+
+ if (wbinvd_on_all_cpus())
+ pr_err("Timed out waiting for cache flush\n");
+#else
+ pr_err("Architecture has no drm_cache.c support\n");
+ WARN_ON_ONCE(1);
+#endif
+}
+EXPORT_SYMBOL(drm_clflush_sg);
+
+/**
+ * drm_clflush_virt_range - Flush dcache lines of a region
+ * @addr: Initial kernel memory address.
+ * @length: Region size.
+ *
+ * Flush every data cache line entry that points to an address in the
+ * region requested.
+ */
+void
+drm_clflush_virt_range(void *addr, unsigned long length)
+{
+#if defined(CONFIG_X86)
+ if (static_cpu_has(X86_FEATURE_CLFLUSH)) {
+ const int size = boot_cpu_data.x86_clflush_size;
+ void *end = addr + length;
+ addr = (void *)(((unsigned long)addr) & -size);
+ mb();
+ for (; addr < end; addr += size)
+ clflushopt(addr);
+ clflushopt(end - 1); /* force serialisation */
+ mb();
+ return;
+ }
+
+ if (wbinvd_on_all_cpus())
+ pr_err("Timed out waiting for cache flush\n");
+#else
+ pr_err("Architecture has no drm_cache.c support\n");
+ WARN_ON_ONCE(1);
+#endif
+}
+EXPORT_SYMBOL(drm_clflush_virt_range);