patch-2.4.19 linux-2.4.19/arch/mips/hp-lj/pci-dma.c

• Lines: 53
• Date: Fri Aug 2 17:39:43 2002
• Orig file: linux-2.4.18/arch/mips/hp-lj/pci-dma.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -urN linux-2.4.18/arch/mips/hp-lj/pci-dma.c linux-2.4.19/arch/mips/hp-lj/pci-dma.c
@@ -0,0 +1,52 @@
+/*
+ * Copyright (C) 2000   Ani Joshi <ajoshi@unixbox.com>
+ *
+ *
+ * Dynamic DMA mapping support.
+ *
+ * swiped from i386, and cloned for MIPS by Geert.
+ *
+ */
+
+#include <linux/types.h>
+#include <linux/mm.h>
+#include <linux/string.h>
+#include <linux/pci.h>
+#include <asm/io.h>
+
+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 || 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);
+
+
+                // REVISIT  this needs reviewal as mentioned in bug report
+                // currently we bump kseg0 allocates to kseg1 uncacheable space
+
+                if ((((unsigned int) ret) & 0xe0000000) == 0x80000000) {
+	           //flush the cache to eliminate coherency problems
+	           // and assure dirty lines won't later get written over any dma, etc.
+                   flush_cache_all();
+		   ret = (void*)((unsigned int)ret | 0x20000000); 
+                }
+
+                
+	}
+	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));
+}
+