From: Hiroshi DOYU <hdoyu at nvidia.com>
This code was based on:
"arch/microblaze/kernel/prom_parse.c"
"arch/powerpc/kernel/prom_parse.c"
"ibm," prefix could be supported with some modification.
Signed-off-by: Hiroshi DOYU <hdoyu at nvidia.com>
---
v2:
- Add several error checks. (Thierry Reding)
- Use property name given to func. (Stephen Warren)
- Support multiple entries. (Stephen Warren)
---
drivers/of/Kconfig | 4 ++
drivers/of/Makefile | 1 +
drivers/of/of_dma.c | 67 ++++++++++++++++++++++++++++++++++++++++++++
include/linux/of_address.h | 13 ++++++++
4 files changed, 85 insertions(+), 0 deletions(-)
diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig
index dfba3e6..3b0298b 100644
--- a/drivers/of/Kconfig
+++ b/drivers/of/Kconfig
@@ -83,4 +83,8 @@ config OF_MTD
depends on MTD
def_bool y
+config OF_DMA
+ depends on HAS_DMA
+ def_bool y
+
endmenu # OF
diff --git a/drivers/of/Makefile b/drivers/of/Makefile
index e027f44..711ff5b 100644
--- a/drivers/of/Makefile
+++ b/drivers/of/Makefile
@@ -11,3 +11,4 @@ obj-$(CONFIG_OF_MDIO) += of_mdio.o
obj-$(CONFIG_OF_PCI) += of_pci.o
obj-$(CONFIG_OF_PCI_IRQ) += of_pci_irq.o
obj-$(CONFIG_OF_MTD) += of_mtd.o
+obj-$(CONFIG_OF_DMA) += of_dma.o
diff --git a/drivers/of/of_dma.c b/drivers/of/of_dma.c
new file mode 100644
index 0000000..80bd7aa
--- /dev/null
+++ b/drivers/of/of_dma.c
@@ -0,0 +1,67 @@
+/*
+ * Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved.
+ *
+ * Based on:
+ * "arch/microblaze/kernel/prom_parse.c"
+ * "arch/powerpc/kernel/prom_parse.c"
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ */
+
+#include <linux/export.h>
+#include <linux/of_address.h>
+
+int of_parse_dma_window(struct device_node *dn,
+ const char *propname, int index,
+ unsigned long *busno,
+ dma_addr_t *addr, size_t *size)
+{
+ const __be32 *dma_window, *end;
+ int bytes, cur_index = 0;
+
+ if (!dn || !propname || !addr || !size)
+ return -EINVAL;
+
+ dma_window = of_get_property(dn, propname, &bytes);
+ if (!dma_window)
+ return -ENODEV;
+ end = dma_window + bytes / sizeof(*dma_window);
+
+ while (dma_window < end) {
+ u32 cells;
+ const void *prop;
+
+ /* busno is always one cell */
+ if (busno)
+ *busno = be32_to_cpup(dma_window++);
+
+ prop = of_get_property(dn, "#dma-address-cells", NULL);
+ if (!prop)
+ prop = of_get_property(dn, "#address-cells", NULL);
+
+ cells = prop ? be32_to_cpup(prop) : of_n_addr_cells(dn);
+ if (!cells)
+ return -EINVAL;
+ *addr = of_read_number(dma_window, cells);
+ dma_window += cells;
+
+ prop = of_get_property(dn, "#dma-size-cells", NULL);
+ cells = prop ? be32_to_cpup(prop) : of_n_size_cells(dn);
+ if (!cells)
+ return -EINVAL;
+ *size = of_read_number(dma_window, cells);
+ dma_window += cells;
+
+ if (cur_index++ == index)
+ break;
+ }
+ return 0;
+}
+EXPORT_SYMBOL(of_parse_dma_window);
diff --git a/include/linux/of_address.h b/include/linux/of_address.h
index 01b925a..1138cd3 100644
--- a/include/linux/of_address.h
+++ b/include/linux/of_address.h
@@ -21,6 +21,11 @@ extern void __iomem *of_iomap(struct device_node *device, int index);
extern const u32 *of_get_address(struct device_node *dev, int index,
u64 *size, unsigned int *flags);
+extern int of_parse_dma_window(struct device_node *dev,
+ const char *propname, int index,
+ unsigned long *busno,
+ dma_addr_t *phys, size_t *size);
+
#ifndef pci_address_to_pio
static inline unsigned long pci_address_to_pio(phys_addr_t addr) { return -1; }
#define pci_address_to_pio pci_address_to_pio
@@ -48,6 +53,14 @@ static inline const u32 *of_get_address(struct device_node *dev, int index,
{
return NULL;
}
+
+extern int of_parse_dma_window(struct device_node *dev,
+ const char *propname, int index,
+ unsigned long *busno,
+ dma_addr_t *phys, size_t *size)
+{
+ return 0;
+}
#endif /* CONFIG_OF_ADDRESS */
--
1.7.5.4