[PATCH v4] Axi-usb: Add support for 64-bit addressing.

From: Nava kishore Manne
Date: Mon May 30 2016 - 12:46:54 EST

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

Signed-off-by: Nava kishore Manne <navam@xxxxxxxxxx>
---
Changes for v4:
-Used boolen property insted of addrwith property in the DT
as suggested by Arnd Bergmann.
-Adopt the DT relevant changes into the driver.

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 | 5 ++-
drivers/usb/gadget/udc/udc-xilinx.c | 52 +++++++++++++++++++++-
2 files changed, 54 insertions(+), 3 deletions(-)

diff --git a/Documentation/devicetree/bindings/usb/udc-xilinx.txt b/Documentation/devicetree/bindings/usb/udc-xilinx.txt
index 47b4e39..d08d972 100644
--- a/Documentation/devicetree/bindings/usb/udc-xilinx.txt
+++ b/Documentation/devicetree/bindings/usb/udc-xilinx.txt
@@ -1,12 +1,14 @@
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
+- xlnx,has-64bit-dma : if DMA is included 64-bit addressing support.

Example:
axi-usb2-device@42e00000 {
@@ -14,5 +16,6 @@ Example:
interrupts = <0x0 0x39 0x1>;
reg = <0x42e00000 0x10000>;
xlnx,has-builtin-dma;
+ xlnx,has-64bit-dma;
};

diff --git a/drivers/usb/gadget/udc/udc-xilinx.c b/drivers/usb/gadget/udc/udc-xilinx.c
index 1cbb0ac..6fb80c6 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 */
@@ -169,6 +178,7 @@ struct xusb_ep {
* @setup: usb_ctrlrequest structure for control requests
* @req: pointer to dummy request for get status command
* @dev: pointer to device structure in gadget
+ * @is_extend_dma: flag indiacting whether the dma is 64-bit support or not.
* @usb_state: device in suspended state or not
* @remote_wkp: remote wakeup enabled by host
* @setupseqtx: tx status
@@ -186,6 +196,7 @@ struct xusb_udc {
struct usb_ctrlrequest setup;
struct xusb_req *req;
struct device *dev;
+ bool is_extend_dma;
u32 usb_state;
u32 remote_wkp;
u32 setupseqtx;
@@ -215,6 +226,20 @@ static const struct usb_endpoint_descriptor config_bulk_out_desc = {
};

/**
+ * xudc_write64 - write 64bit value to device registers
+ * @ep: pointer to the usb device endpoint structure.
+ * @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
* @offset: register offset
@@ -330,8 +355,13 @@ 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->is_extend_dma) {
+ 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 +2127,23 @@ static int xudc_probe(struct platform_device *pdev)

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

+ udc->is_extend_dma = false;
+
+ if (of_device_is_compatible(np, "xlnx,usb2-device-5.00"))
+ udc->is_extend_dma = of_property_read_bool(np,
+ "xlnx,has-64bit-dma");
+
+ /* Set the dma mask bits */
+ if (udc->is_extend_dma)
+ ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
+ else
+ ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
+
+ 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 +2215,7 @@ 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);
--
2.1.1