efDataDiscreteRateMining dataMonitoring.c 韩正义 commit at 2020-11-04

efDataDiscreteRateMining/externalListeningThread/dataMonitoring.c

@@ -650,3 +650,155 @@ static void *__dma_alloc(struct device *dev, size_t size, dma_addr_t *handle,
 
 	if (addr)
 		*handle = pfn_to_dma(dev, page_to_pfn(page));
+
+	return addr;
+}
+
+/*
+ * Allocate DMA-coherent memory space and return both the kernel remapped
+ * virtual and bus address for that space.
+ */
+void *arm_dma_alloc(struct device *dev, size_t size, dma_addr_t *handle,
+		    gfp_t gfp, struct dma_attrs *attrs)
+{
+	pgprot_t prot = __get_dma_pgprot(attrs, pgprot_kernel);
+	void *memory;
+
+	if (dma_alloc_from_coherent(dev, size, handle, &memory))
+		return memory;
+
+	return __dma_alloc(dev, size, handle, gfp, prot, false,
+			   __builtin_return_address(0));
+}
+
+static void *arm_coherent_dma_alloc(struct device *dev, size_t size,
+	dma_addr_t *handle, gfp_t gfp, struct dma_attrs *attrs)
+{
+	pgprot_t prot = __get_dma_pgprot(attrs, pgprot_kernel);
+	void *memory;
+
+	if (dma_alloc_from_coherent(dev, size, handle, &memory))
+		return memory;
+
+	return __dma_alloc(dev, size, handle, gfp, prot, true,
+			   __builtin_return_address(0));
+}
+
+/*
+ * Create userspace mapping for the DMA-coherent memory.
+ */
+int arm_dma_mmap(struct device *dev, struct vm_area_struct *vma,
+		 void *cpu_addr, dma_addr_t dma_addr, size_t size,
+		 struct dma_attrs *attrs)
+{
+	int ret = -ENXIO;
+#ifdef CONFIG_MMU
+	unsigned long nr_vma_pages = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
+	unsigned long nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT;
+	unsigned long pfn = dma_to_pfn(dev, dma_addr);
+	unsigned long off = vma->vm_pgoff;
+
+	vma->vm_page_prot = __get_dma_pgprot(attrs, vma->vm_page_prot);
+
+	if (dma_mmap_from_coherent(dev, vma, cpu_addr, size, &ret))
+		return ret;
+
+	if (off < nr_pages && nr_vma_pages <= (nr_pages - off)) {
+		ret = remap_pfn_range(vma, vma->vm_start,
+				      pfn + off,
+				      vma->vm_end - vma->vm_start,
+				      vma->vm_page_prot);
+	}
+#endif	/* CONFIG_MMU */
+
+	return ret;
+}
+
+/*
+ * Free a buffer as defined by the above mapping.
+ */
+static void __arm_dma_free(struct device *dev, size_t size, void *cpu_addr,
+			   dma_addr_t handle, struct dma_attrs *attrs,
+			   bool is_coherent)
+{
+	struct page *page = pfn_to_page(dma_to_pfn(dev, handle));
+
+	if (dma_release_from_coherent(dev, get_order(size), cpu_addr))
+		return;
+
+	size = PAGE_ALIGN(size);
+
+	if (is_coherent || nommu()) {
+		__dma_free_buffer(page, size);
+	} else if (__free_from_pool(cpu_addr, size)) {
+		return;
+	} else if (!IS_ENABLED(CONFIG_CMA)) {
+		__dma_free_remap(cpu_addr, size);
+		__dma_free_buffer(page, size);
+	} else {
+		/*
+		 * Non-atomic allocations cannot be freed with IRQs disabled
+		 */
+		WARN_ON(irqs_disabled());
+		__free_from_contiguous(dev, page, size);
+	}
+}
+
+void arm_dma_free(struct device *dev, size_t size, void *cpu_addr,
+		  dma_addr_t handle, struct dma_attrs *attrs)
+{
+	__arm_dma_free(dev, size, cpu_addr, handle, attrs, false);
+}
+
+static void arm_coherent_dma_free(struct device *dev, size_t size, void *cpu_addr,
+				  dma_addr_t handle, struct dma_attrs *attrs)
+{
+	__arm_dma_free(dev, size, cpu_addr, handle, attrs, true);
+}
+
+int arm_dma_get_sgtable(struct device *dev, struct sg_table *sgt,
+		 void *cpu_addr, dma_addr_t handle, size_t size,
+		 struct dma_attrs *attrs)
+{
+	struct page *page = pfn_to_page(dma_to_pfn(dev, handle));
+	int ret;
+
+	ret = sg_alloc_table(sgt, 1, GFP_KERNEL);
+	if (unlikely(ret))
+		return ret;
+
+	sg_set_page(sgt->sgl, page, PAGE_ALIGN(size), 0);
+	return 0;
+}
+
+static void dma_cache_maint_page(struct page *page, unsigned long offset,
+	size_t size, enum dma_data_direction dir,
+	void (*op)(const void *, size_t, int))
+{
+	unsigned long pfn;
+	size_t left = size;
+
+	pfn = page_to_pfn(page) + offset / PAGE_SIZE;
+	offset %= PAGE_SIZE;
+
+	/*
+	 * A single sg entry may refer to multiple physically contiguous
+	 * pages.  But we still need to process highmem pages individually.
+	 * If highmem is not configured then the bulk of this loop gets
+	 * optimized out.
+	 */
+	do {
+		size_t len = left;
+		void *vaddr;
+
+		page = pfn_to_page(pfn);
+
+		if (PageHighMem(page)) {
+			if (len + offset > PAGE_SIZE)
+				len = PAGE_SIZE - offset;
+			vaddr = kmap_high_get(page);
+			if (vaddr) {
+				vaddr += offset;
+				op(vaddr, len, dir);
+				kunmap_high(page);
+			} else if (cache_is_vipt()) {