[PATCH v3] Axi-usb: Add support for 64-bit addressing.

Nava kishore Manne
2016-05-24T05:21:08Z

This patch updates the driver to support 64-bit DMA addressing.

Signed-off-by: Nava kishore Manne <navam@xilinx.com>
---
Changes for v3:
-Added new compatable string for 5.00 IP version as suggested by
Arnd Bergmann.
-Used write_fn() insted of lo_hi_writeq() as suggested by
Arnd Bergmann.

Changes for v2:
-Added dma-ranges property in device tree as suggested by Arnd Bergmann.
-Modified the driver code based on the xlnx,addrwidth.

.../devicetree/bindings/usb/udc-xilinx.txt | 21 +++++----
drivers/usb/gadget/udc/udc-xilinx.c | 53 ++++++++++++++++++++--
2 files changed, 63 insertions(+), 11 deletions(-)

diff --git a/Documentation/devicetree/bindings/usb/udc-xilinx.txt b/Documentation/devicetree/bindings/usb/udc-xilinx.txt
index 47b4e39..09df757 100644
--- a/Documentation/devicetree/bindings/usb/udc-xilinx.txt
+++ b/Documentation/devicetree/bindings/usb/udc-xilinx.txt
@@ -1,18 +1,23 @@
Xilinx USB2 device controller

Required properties:
-- compatible : Should be "xlnx,usb2-device-4.00.a"
+- compatible : Should be "xlnx,usb2-device-4.00.a" or
+ "xlnx,usb2-device-5.00"
- reg : Physical base address and size of the USB2
device registers map.
- interrupts : Should contain single irq line of USB2 device
controller
- xlnx,has-builtin-dma : if DMA is included
+- dma-ranges : Should be as the following
+ <child-bus-address, parent-bus-address, length>
+- xlnx,addrwidth : Should be the dma addressing size in bits(ex: 64 bits)

Example:
- axi-usb2-device at 42e00000 {
- compatible = "xlnx,usb2-device-4.00.a";
- interrupts = <0x0 0x39 0x1>;
- reg = <0x42e00000 0x10000>;
- xlnx,has-builtin-dma;
- };
-
+ axi-usb2-device at 42e00000 {
+ compatible = "xlnx,usb2-device-4.00.a";
+ interrupts = <0x0 0x39 0x1>;
+ reg = <0x42e00000 0x10000>;
+ dma-ranges = <0x00000000 0x00000000 0x40000000>;
+ xlnx,has-builtin-dma;
+ xlnx,addrwidth = <0x40>;
+ };
diff --git a/drivers/usb/gadget/udc/udc-xilinx.c b/drivers/usb/gadget/udc/udc-xilinx.c
index 1cbb0ac..112a6f3 100644
--- a/drivers/usb/gadget/udc/udc-xilinx.c
+++ b/drivers/usb/gadget/udc/udc-xilinx.c
@@ -47,6 +47,15 @@
#define XUSB_DMA_LENGTH_OFFSET 0x0210 /* DMA Length Register */
#define XUSB_DMA_STATUS_OFFSET 0x0214 /* DMA Status Register */

+/* DMA source Address Reg for LSB */
+#define XUSB_DMA_DSAR_ADDR_OFFSET_LSB 0x0308
+/* DMA source Address Reg for MSB */
+#define XUSB_DMA_DSAR_ADDR_OFFSET_MSB 0x030C
+/* DMA destination Addr Reg LSB */
+#define XUSB_DMA_DDAR_ADDR_OFFSET_LSB 0x0310
+/* DMA destination Addr Reg MSB */
+#define XUSB_DMA_DDAR_ADDR_OFFSET_MSB 0x0314
+
/* Endpoint Configuration Space offsets */
#define XUSB_EP_CFGSTATUS_OFFSET 0x00 /* Endpoint Config Status */
#define XUSB_EP_BUF0COUNT_OFFSET 0x08 /* Buffer 0 Count */
@@ -193,7 +202,7 @@ struct xusb_udc {
void __iomem *addr;
spinlock_t lock;
bool dma_enabled;
-
+ u32 dma_addrwidth;
unsigned int (*read_fn)(void __iomem *);
void (*write_fn)(void __iomem *, u32, u32);
};
@@ -214,6 +223,20 @@ static const struct usb_endpoint_descriptor config_bulk_out_desc = {
.wMaxPacketSize = cpu_to_le16(EP0_MAX_PACKET),
};

+/**
+ * xudc_write64 - write 64bit value to device registers
+ * @addr: base addr of device registers
+ * @offset: register offset
+ * @val: data to be written
+ **/
+static void xudc_write64(struct xusb_ep *ep, u32 offset, u64 val)
+{
+ struct xusb_udc *udc = ep->udc;
+
+ udc->write_fn(udc->addr, offset, lower_32_bits(val));
+ udc->write_fn(udc->addr, offset+0x04, upper_32_bits(val));
+}
+
/**
* xudc_write32 - little endian write to device registers
* @addr: base addr of device registers
@@ -330,8 +353,13 @@ static int xudc_start_dma(struct xusb_ep *ep, dma_addr_t src,
* destination registers and then set the length
* into the DMA length register.
*/
- udc->write_fn(udc->addr, XUSB_DMA_DSAR_ADDR_OFFSET, src);
- udc->write_fn(udc->addr, XUSB_DMA_DDAR_ADDR_OFFSET, dst);
+ if (udc->dma_addrwidth > 32) {
+ xudc_write64(ep, XUSB_DMA_DSAR_ADDR_OFFSET_LSB, src);
+ xudc_write64(ep, XUSB_DMA_DDAR_ADDR_OFFSET_LSB, dst);
+ } else {
+ udc->write_fn(udc->addr, XUSB_DMA_DSAR_ADDR_OFFSET, src);
+ udc->write_fn(udc->addr, XUSB_DMA_DDAR_ADDR_OFFSET, dst);
+ }
udc->write_fn(udc->addr, XUSB_DMA_LENGTH_OFFSET, length);

/*
@@ -2097,6 +2125,24 @@ static int xudc_probe(struct platform_device *pdev)

udc->dma_enabled = of_property_read_bool(np, "xlnx,has-builtin-dma");

+ if (of_device_is_compatible(np, "xlnx,usb2-device-5.00")) {
+ ret = of_property_read_u32(np, "xlnx,addrwidth",
+ &udc->dma_addrwidth);
+ if (ret < 0)
+ dev_warn(&pdev->dev,
+ "missing xlnx,addrwidth property\n");
+ } else {
+ udc->dma_addrwidth = 32;
+ }
+
+ /* Set the dma mask bits */
+ ret = dma_set_mask_and_coherent(&pdev->dev,
+ DMA_BIT_MASK(udc->dma_addrwidth));
+ if (ret < 0) {
+ dev_dbg(&pdev->dev, "no usable DMA configuration");
+ goto fail;
+ }
+
/* Setup gadget structure */
udc->gadget.ops = &xusb_udc_ops;
udc->gadget.max_speed = USB_SPEED_HIGH;
@@ -2168,6 +2214,7 @@ static int xudc_remove(struct platform_device *pdev)
/* Match table for of_platform binding */
static const struct of_device_id usb_of_match[] = {
{ .compatible = "xlnx,usb2-device-4.00.a", },
+ { .compatible = "xlnx,usb2-device-5.00", },
{ /* end of list */ },
};
MODULE_DEVICE_TABLE(of, usb_of_match);
--
2.8.3.394.g3916adf