patch-2.4.20 linux-2.4.20/arch/x86_64/kernel/pci-nommu.c

• Lines: 49
• Date: Thu Nov 28 15:53:12 2002
• Orig file: linux-2.4.19/arch/x86_64/kernel/pci-nommu.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -urN linux-2.4.19/arch/x86_64/kernel/pci-nommu.c linux-2.4.20/arch/x86_64/kernel/pci-nommu.c
@@ -0,0 +1,48 @@
+#include <linux/mm.h>
+#include <linux/init.h>
+#include <linux/pci.h>
+#include <linux/string.h>
+
+/* 
+ * Dummy IO MMU functions
+ */
+
+extern unsigned long end_pfn;
+
+void *pci_alloc_consistent(struct pci_dev *hwdev, size_t size,
+			   dma_addr_t *dma_handle)
+{
+	void *ret;
+	int gfp = GFP_ATOMIC;
+	
+	if (hwdev == NULL ||
+	    end_pfn > (hwdev->dma_mask>>PAGE_SHIFT) ||  /* XXX */
+	    (u32)hwdev->dma_mask < 0xffffffff)
+		gfp |= GFP_DMA;
+	ret = (void *)__get_free_pages(gfp, get_order(size));
+
+	if (ret != NULL) {
+		memset(ret, 0, size);
+		*dma_handle = virt_to_bus(ret);
+	}
+	return ret;
+}
+
+void pci_free_consistent(struct pci_dev *hwdev, size_t size,
+			 void *vaddr, dma_addr_t dma_handle)
+{
+	free_pages((unsigned long)vaddr, get_order(size));
+}
+
+
+static void __init check_ram(void) 
+{ 
+	if (end_pfn >= 0xffffffff>>PAGE_SHIFT) { 
+		printk(KERN_ERR "WARNING more than 4GB of memory but no IOMMU.\n"
+		       KERN_ERR "WARNING 32bit PCI may malfunction.\n"); 
+		/* Could play with highmem_start_page here to trick some subsystems
+		   into bounce buffers. Unfortunately that would require setting
+		   CONFIG_HIGHMEM too. 
+		 */ 
+	} 
+}