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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-17 02:20:36 +0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-17 02:20:36 +0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/parisc/ccio-rm-dma.c
downloadlinux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.xz
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'drivers/parisc/ccio-rm-dma.c')
-rw-r--r--drivers/parisc/ccio-rm-dma.c201
1 files changed, 201 insertions, 0 deletions
diff --git a/drivers/parisc/ccio-rm-dma.c b/drivers/parisc/ccio-rm-dma.c
new file mode 100644
index 000000000000..57e6385976e2
--- /dev/null
+++ b/drivers/parisc/ccio-rm-dma.c
@@ -0,0 +1,201 @@
+/*
+ * ccio-rm-dma.c:
+ * DMA management routines for first generation cache-coherent machines.
+ * "Real Mode" operation refers to U2/Uturn chip operation. The chip
+ * can perform coherency checks w/o using the I/O MMU. That's all we
+ * need until support for more than 4GB phys mem is needed.
+ *
+ * This is the trivial case - basically what x86 does.
+ *
+ * Drawbacks of using Real Mode are:
+ * o outbound DMA is slower since one isn't using the prefetching
+ * U2 can do for outbound DMA.
+ * o Ability to do scatter/gather in HW is also lost.
+ * o only known to work with PCX-W processor. (eg C360)
+ * (PCX-U/U+ are not coherent with U2 in real mode.)
+ *
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ *
+ * Original version/author:
+ * CVSROOT=:pserver:anonymous@198.186.203.37:/cvsroot/linux-parisc
+ * cvs -z3 co linux/arch/parisc/kernel/dma-rm.c
+ *
+ * (C) Copyright 2000 Philipp Rumpf <prumpf@tux.org>
+ *
+ *
+ * Adopted for The Puffin Group's parisc-linux port by Grant Grundler.
+ * (C) Copyright 2000 Grant Grundler <grundler@puffin.external.hp.com>
+ *
+ */
+
+#include <linux/types.h>
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <linux/string.h>
+#include <linux/pci.h>
+
+#include <asm/uaccess.h>
+
+#include <asm/io.h>
+#include <asm/hardware.h>
+#include <asm/page.h>
+
+/* Only chose "ccio" since that's what HP-UX calls it....
+** Make it easier for folks to migrate from one to the other :^)
+*/
+#define MODULE_NAME "ccio"
+
+#define U2_IOA_RUNWAY 0x580
+#define U2_BC_GSC 0x501
+#define UTURN_IOA_RUNWAY 0x581
+#define UTURN_BC_GSC 0x502
+
+#define IS_U2(id) ( \
+ (((id)->hw_type == HPHW_IOA) && ((id)->hversion == U2_IOA_RUNWAY)) || \
+ (((id)->hw_type == HPHW_BCPORT) && ((id)->hversion == U2_BC_GSC)) \
+)
+
+#define IS_UTURN(id) ( \
+ (((id)->hw_type == HPHW_IOA) && ((id)->hversion == UTURN_IOA_RUNWAY)) || \
+ (((id)->hw_type == HPHW_BCPORT) && ((id)->hversion == UTURN_BC_GSC)) \
+)
+
+static int ccio_dma_supported( struct pci_dev *dev, u64 mask)
+{
+ if (dev == NULL) {
+ printk(KERN_ERR MODULE_NAME ": EISA/ISA/et al not supported\n");
+ BUG();
+ return(0);
+ }
+
+ /* only support 32-bit devices (ie PCI/GSC) */
+ return((int) (mask >= 0xffffffffUL));
+}
+
+
+static void *ccio_alloc_consistent(struct pci_dev *dev, size_t size,
+ dma_addr_t *handle)
+{
+ void *ret;
+
+ ret = (void *)__get_free_pages(GFP_ATOMIC, get_order(size));
+
+ if (ret != NULL) {
+ memset(ret, 0, size);
+ *handle = virt_to_phys(ret);
+ }
+ return ret;
+}
+
+static void ccio_free_consistent(struct pci_dev *dev, size_t size,
+ void *vaddr, dma_addr_t handle)
+{
+ free_pages((unsigned long)vaddr, get_order(size));
+}
+
+static dma_addr_t ccio_map_single(struct pci_dev *dev, void *ptr, size_t size,
+ int direction)
+{
+ return virt_to_phys(ptr);
+}
+
+static void ccio_unmap_single(struct pci_dev *dev, dma_addr_t dma_addr,
+ size_t size, int direction)
+{
+ /* Nothing to do */
+}
+
+
+static int ccio_map_sg(struct pci_dev *dev, struct scatterlist *sglist, int nents, int direction)
+{
+ int tmp = nents;
+
+ /* KISS: map each buffer separately. */
+ while (nents) {
+ sg_dma_address(sglist) = ccio_map_single(dev, sglist->address, sglist->length, direction);
+ sg_dma_len(sglist) = sglist->length;
+ nents--;
+ sglist++;
+ }
+
+ return tmp;
+}
+
+
+static void ccio_unmap_sg(struct pci_dev *dev, struct scatterlist *sglist, int nents, int direction)
+{
+#if 0
+ while (nents) {
+ ccio_unmap_single(dev, sg_dma_address(sglist), sg_dma_len(sglist), direction);
+ nents--;
+ sglist++;
+ }
+ return;
+#else
+ /* Do nothing (copied from current ccio_unmap_single() :^) */
+#endif
+}
+
+
+static struct pci_dma_ops ccio_ops = {
+ ccio_dma_supported,
+ ccio_alloc_consistent,
+ ccio_free_consistent,
+ ccio_map_single,
+ ccio_unmap_single,
+ ccio_map_sg,
+ ccio_unmap_sg,
+ NULL, /* dma_sync_single_for_cpu : NOP for U2 */
+ NULL, /* dma_sync_single_for_device : NOP for U2 */
+ NULL, /* dma_sync_sg_for_cpu : ditto */
+ NULL, /* dma_sync_sg_for_device : ditto */
+};
+
+
+/*
+** Determine if u2 should claim this chip (return 0) or not (return 1).
+** If so, initialize the chip and tell other partners in crime they
+** have work to do.
+*/
+static int
+ccio_probe(struct parisc_device *dev)
+{
+ printk(KERN_INFO "%s found %s at 0x%lx\n", MODULE_NAME,
+ dev->id.hversion == U2_BC_GSC ? "U2" : "UTurn",
+ dev->hpa);
+
+/*
+** FIXME - should check U2 registers to verify it's really running
+** in "Real Mode".
+*/
+
+#if 0
+/* will need this for "Virtual Mode" operation */
+ ccio_hw_init(ccio_dev);
+ ccio_common_init(ccio_dev);
+#endif
+ hppa_dma_ops = &ccio_ops;
+ return 0;
+}
+
+static struct parisc_device_id ccio_tbl[] = {
+ { HPHW_BCPORT, HVERSION_REV_ANY_ID, U2_BC_GSC, 0xc },
+ { HPHW_BCPORT, HVERSION_REV_ANY_ID, UTURN_BC_GSC, 0xc },
+ { 0, }
+};
+
+static struct parisc_driver ccio_driver = {
+ .name = "U2/Uturn",
+ .id_table = ccio_tbl,
+ .probe = ccio_probe,
+};
+
+void __init ccio_init(void)
+{
+ register_parisc_driver(&ccio_driver);
+}