USB: fsl_udc_core: prepare for SoCs with BE registers and descriptors

On some SoCs, the USB controller registers and descriptors can be big
or little endian, depending on the version of the chip. In order to be
able to run the same kernel binary on different versions of an SoC, the
BE/LE decision must be made at run time. Provide appropriate register
and descriptor accessors which are configurable at run time using the
configuration flags from fsl_usb2_platform_data data structure.

This is in preparation for adding support for MPC5121E DR USB2 Controller
to the FSL UDC driver.

Signed-off-by: Anatolij Gustschin <agust@denx.de>
Cc: Li Yang <leoli@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

2 files changed, 100 insertions, 25 deletions

diff --git a/drivers/usb/gadget/fsl_udc_core.c b/drivers/usb/gadget/fsl_udc_core.c
index 07499c1cdcc4..b101b7e9c9b6 100644
--- a/drivers/usb/gadget/fsl_udc_core.c
+++ b/drivers/usb/gadget/fsl_udc_core.c
@@ -77,12 +77,64 @@ fsl_ep0_desc = {
 static void fsl_ep_fifo_flush(struct usb_ep *_ep);
 
 #ifdef CONFIG_PPC32
-#define fsl_readl(addr)		in_le32(addr)
-#define fsl_writel(val32, addr) out_le32(addr, val32)
-#else
+/*
+ * On some SoCs, the USB controller registers can be big or little endian,
+ * depending on the version of the chip. In order to be able to run the
+ * same kernel binary on 2 different versions of an SoC, the BE/LE decision
+ * must be made at run time. _fsl_readl and fsl_writel are pointers to the
+ * BE or LE readl() and writel() functions, and fsl_readl() and fsl_writel()
+ * call through those pointers. Platform code for SoCs that have BE USB
+ * registers should set pdata->big_endian_mmio flag.
+ *
+ * This also applies to controller-to-cpu accessors for the USB descriptors,
+ * since their endianness is also SoC dependant. Platform code for SoCs that
+ * have BE USB descriptors should set pdata->big_endian_desc flag.
+ */
+static u32 _fsl_readl_be(const unsigned __iomem *p)
+{
+	return in_be32(p);
+}
+
+static u32 _fsl_readl_le(const unsigned __iomem *p)
+{
+	return in_le32(p);
+}
+
+static void _fsl_writel_be(u32 v, unsigned __iomem *p)
+{
+	out_be32(p, v);
+}
+
+static void _fsl_writel_le(u32 v, unsigned __iomem *p)
+{
+	out_le32(p, v);
+}
+
+static u32 (*_fsl_readl)(const unsigned __iomem *p);
+static void (*_fsl_writel)(u32 v, unsigned __iomem *p);
+
+#define fsl_readl(p)		(*_fsl_readl)((p))
+#define fsl_writel(v, p)	(*_fsl_writel)((v), (p))
+
+static inline u32 cpu_to_hc32(const u32 x)
+{
+	return udc_controller->pdata->big_endian_desc
+		? (__force u32)cpu_to_be32(x)
+		: (__force u32)cpu_to_le32(x);
+}
+
+static inline u32 hc32_to_cpu(const u32 x)
+{
+	return udc_controller->pdata->big_endian_desc
+		? be32_to_cpu((__force __be32)x)
+		: le32_to_cpu((__force __le32)x);
+}
+#else /* !CONFIG_PPC32 */
 #define fsl_readl(addr)		readl(addr)
 #define fsl_writel(val32, addr) writel(val32, addr)
-#endif
+#define cpu_to_hc32(x)		cpu_to_le32(x)
+#define hc32_to_cpu(x)		le32_to_cpu(x)
+#endif /* CONFIG_PPC32 */
 
 /********************************************************************
  *	Internal Used Function
@@ -409,7 +461,7 @@ static void struct_ep_qh_setup(struct fsl_udc *udc, unsigned char ep_num,
 	if (zlt)
 		tmp |= EP_QUEUE_HEAD_ZLT_SEL;
 
-	p_QH->max_pkt_length = cpu_to_le32(tmp);
+	p_QH->max_pkt_length = cpu_to_hc32(tmp);
 	p_QH->next_dtd_ptr = 1;
 	p_QH->size_ioc_int_sts = 0;
 }
@@ -616,7 +668,7 @@ static void fsl_queue_td(struct fsl_ep *ep, struct fsl_req *req)
 		struct fsl_req *lastreq;
 		lastreq = list_entry(ep->queue.prev, struct fsl_req, queue);
 		lastreq->tail->next_td_ptr =
-			cpu_to_le32(req->head->td_dma & DTD_ADDR_MASK);
+			cpu_to_hc32(req->head->td_dma & DTD_ADDR_MASK);
 		/* Read prime bit, if 1 goto done */
 		if (fsl_readl(&dr_regs->endpointprime) & bitmask)
 			goto out;
@@ -641,10 +693,10 @@ static void fsl_queue_td(struct fsl_ep *ep, struct fsl_req *req)
 
 	/* Write dQH next pointer and terminate bit to 0 */
 	temp = req->head->td_dma & EP_QUEUE_HEAD_NEXT_POINTER_MASK;
-	dQH->next_dtd_ptr = cpu_to_le32(temp);
+	dQH->next_dtd_ptr = cpu_to_hc32(temp);
 
 	/* Clear active and halt bit */
-	temp = cpu_to_le32(~(EP_QUEUE_HEAD_STATUS_ACTIVE
+	temp = cpu_to_hc32(~(EP_QUEUE_HEAD_STATUS_ACTIVE
 			| EP_QUEUE_HEAD_STATUS_HALT));
 	dQH->size_ioc_int_sts &= temp;
 
@@ -682,17 +734,17 @@ static struct ep_td_struct *fsl_build_dtd(struct fsl_req *req, unsigned *length,
 
 	dtd->td_dma = *dma;
 	/* Clear reserved field */
-	swap_temp = cpu_to_le32(dtd->size_ioc_sts);
+	swap_temp = hc32_to_cpu(dtd->size_ioc_sts);
 	swap_temp &= ~DTD_RESERVED_FIELDS;
-	dtd->size_ioc_sts = cpu_to_le32(swap_temp);
+	dtd->size_ioc_sts = cpu_to_hc32(swap_temp);
 
 	/* Init all of buffer page pointers */
 	swap_temp = (u32) (req->req.dma + req->req.actual);
-	dtd->buff_ptr0 = cpu_to_le32(swap_temp);
-	dtd->buff_ptr1 = cpu_to_le32(swap_temp + 0x1000);
-	dtd->buff_ptr2 = cpu_to_le32(swap_temp + 0x2000);
-	dtd->buff_ptr3 = cpu_to_le32(swap_temp + 0x3000);
-	dtd->buff_ptr4 = cpu_to_le32(swap_temp + 0x4000);
+	dtd->buff_ptr0 = cpu_to_hc32(swap_temp);
+	dtd->buff_ptr1 = cpu_to_hc32(swap_temp + 0x1000);
+	dtd->buff_ptr2 = cpu_to_hc32(swap_temp + 0x2000);
+	dtd->buff_ptr3 = cpu_to_hc32(swap_temp + 0x3000);
+	dtd->buff_ptr4 = cpu_to_hc32(swap_temp + 0x4000);
 
 	req->req.actual += *length;
 
@@ -716,7 +768,7 @@ static struct ep_td_struct *fsl_build_dtd(struct fsl_req *req, unsigned *length,
 	if (*is_last && !req->req.no_interrupt)
 		swap_temp |= DTD_IOC;
 
-	dtd->size_ioc_sts = cpu_to_le32(swap_temp);
+	dtd->size_ioc_sts = cpu_to_hc32(swap_temp);
 
 	mb();
 
@@ -743,7 +795,7 @@ static int fsl_req_to_dtd(struct fsl_req *req)
 			is_first = 0;
 			req->head = dtd;
 		} else {
-			last_dtd->next_td_ptr = cpu_to_le32(dma);
+			last_dtd->next_td_ptr = cpu_to_hc32(dma);
 			last_dtd->next_td_virt = dtd;
 		}
 		last_dtd = dtd;
@@ -751,7 +803,7 @@ static int fsl_req_to_dtd(struct fsl_req *req)
 		req->dtd_count++;
 	} while (!is_last);
 
-	dtd->next_td_ptr = cpu_to_le32(DTD_NEXT_TERMINATE);
+	dtd->next_td_ptr = cpu_to_hc32(DTD_NEXT_TERMINATE);
 
 	req->tail = dtd;
 
@@ -1394,6 +1446,7 @@ static void tripwire_handler(struct fsl_udc *udc, u8 ep_num, u8 *buffer_ptr)
 {
 	u32 temp;
 	struct ep_queue_head *qh;
+	struct fsl_usb2_platform_data *pdata = udc->pdata;
 
 	qh = &udc->ep_qh[ep_num * 2 + EP_DIR_OUT];
 
@@ -1408,7 +1461,16 @@ static void tripwire_handler(struct fsl_udc *udc, u8 ep_num, u8 *buffer_ptr)
 		fsl_writel(temp | USB_CMD_SUTW, &dr_regs->usbcmd);
 
 		/* Copy the setup packet to local buffer */
-		memcpy(buffer_ptr, (u8 *) qh->setup_buffer, 8);
+		if (pdata->le_setup_buf) {
+			u32 *p = (u32 *)buffer_ptr;
+			u32 *s = (u32 *)qh->setup_buffer;
+
+			/* Convert little endian setup buffer to CPU endian */
+			*p++ = le32_to_cpu(*s++);
+			*p = le32_to_cpu(*s);
+		} else {
+			memcpy(buffer_ptr, (u8 *) qh->setup_buffer, 8);
+		}
 	} while (!(fsl_readl(&dr_regs->usbcmd) & USB_CMD_SUTW));
 
 	/* Clear Setup Tripwire */
@@ -1432,19 +1494,19 @@ static int process_ep_req(struct fsl_udc *udc, int pipe,
 	actual = curr_req->req.length;
 
 	for (j = 0; j < curr_req->dtd_count; j++) {
-		remaining_length = (le32_to_cpu(curr_td->size_ioc_sts)
+		remaining_length = (hc32_to_cpu(curr_td->size_ioc_sts)
 					& DTD_PACKET_SIZE)
 				>> DTD_LENGTH_BIT_POS;
 		actual -= remaining_length;
 
-		if ((errors = le32_to_cpu(curr_td->size_ioc_sts) &
-						DTD_ERROR_MASK)) {
+		errors = hc32_to_cpu(curr_td->size_ioc_sts);
+		if (errors & DTD_ERROR_MASK) {
 			if (errors & DTD_STATUS_HALTED) {
 				ERR("dTD error %08x QH=%d\n", errors, pipe);
 				/* Clear the errors and Halt condition */
-				tmp = le32_to_cpu(curr_qh->size_ioc_int_sts);
+				tmp = hc32_to_cpu(curr_qh->size_ioc_int_sts);
 				tmp &= ~errors;
-				curr_qh->size_ioc_int_sts = cpu_to_le32(tmp);
+				curr_qh->size_ioc_int_sts = cpu_to_hc32(tmp);
 				status = -EPIPE;
 				/* FIXME: continue with next queued TD? */
 
@@ -1462,7 +1524,7 @@ static int process_ep_req(struct fsl_udc *udc, int pipe,
 				ERR("Unknown error has occurred (0x%x)!\n",
 					errors);
 
-		} else if (le32_to_cpu(curr_td->size_ioc_sts)
+		} else if (hc32_to_cpu(curr_td->size_ioc_sts)
 				& DTD_STATUS_ACTIVE) {
 			VDBG("Request not complete");
 			status = REQ_UNCOMPLETE;
@@ -2233,6 +2295,7 @@ static int __init struct_ep_setup(struct fsl_udc *udc, unsigned char index,
  */
 static int __init fsl_udc_probe(struct platform_device *pdev)
 {
+	struct fsl_usb2_platform_data *pdata;
 	struct resource *res;
 	int ret = -ENODEV;
 	unsigned int i;
@@ -2249,6 +2312,8 @@ static int __init fsl_udc_probe(struct platform_device *pdev)
 		return -ENOMEM;
 	}
 
+	pdata = pdev->dev.platform_data;
+	udc_controller->pdata = pdata;
 	spin_lock_init(&udc_controller->lock);
 	udc_controller->stopped = 1;
 
@@ -2271,6 +2336,14 @@ static int __init fsl_udc_probe(struct platform_device *pdev)
 		goto err_release_mem_region;
 	}
 
+	if (pdata->big_endian_mmio) {
+		_fsl_readl = _fsl_readl_be;
+		_fsl_writel = _fsl_writel_be;
+	} else {
+		_fsl_readl = _fsl_readl_le;
+		_fsl_writel = _fsl_writel_le;
+	}
+
 #ifndef CONFIG_ARCH_MXC
 	usb_sys_regs = (struct usb_sys_interface *)
 			((u32)dr_regs + USB_DR_SYS_OFFSET);
diff --git a/drivers/usb/gadget/fsl_usb2_udc.h b/drivers/usb/gadget/fsl_usb2_udc.h
index e88cce5c2c0d..24efba93cef5 100644
--- a/drivers/usb/gadget/fsl_usb2_udc.h
+++ b/drivers/usb/gadget/fsl_usb2_udc.h
@@ -461,6 +461,7 @@ struct fsl_ep {
 struct fsl_udc {
 	struct usb_gadget gadget;
 	struct usb_gadget_driver *driver;
+	struct fsl_usb2_platform_data *pdata;
 	struct completion *done;	/* to make sure release() is done */
 	struct fsl_ep *eps;
 	unsigned int max_ep;
@@ -473,6 +474,7 @@ struct fsl_udc {
 	unsigned vbus_active:1;
 	unsigned stopped:1;
 	unsigned remote_wakeup:1;
+	unsigned big_endian_desc:1;
 
 	struct ep_queue_head *ep_qh;	/* Endpoints Queue-Head */
 	struct fsl_req *status_req;	/* ep0 status request */