summaryrefslogtreecommitdiffstats
path: root/arch/sh/boards/overdrive/pcidma.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/sh/boards/overdrive/pcidma.c')
-rw-r--r--arch/sh/boards/overdrive/pcidma.c46
1 files changed, 46 insertions, 0 deletions
diff --git a/arch/sh/boards/overdrive/pcidma.c b/arch/sh/boards/overdrive/pcidma.c
new file mode 100644
index 000000000000..1c9bfeda00b7
--- /dev/null
+++ b/arch/sh/boards/overdrive/pcidma.c
@@ -0,0 +1,46 @@
+/*
+ * Copyright (C) 2000 David J. Mckay (david.mckay@st.com)
+ *
+ * May be copied or modified under the terms of the GNU General Public
+ * License. See linux/COPYING for more information.
+ *
+ * Dynamic DMA mapping support.
+ *
+ * On the overdrive, we can only DMA from memory behind the PCI bus!
+ * this means that all DMA'able memory must come from there.
+ * this restriction will not apply to later boards.
+ */
+
+#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;
+
+ printk("BUG: pci_alloc_consistent() called - not yet supported\n");
+ /* We ALWAYS need DMA memory on the overdrive hardware,
+ * due to it's extreme weirdness
+ * Need to flush the cache here as well, since the memory
+ * can still be seen through the cache!
+ */
+ 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));
+}