usb: musb dma: add cppi41 dma driver

This driver is currently used by musb' cppi41 couter part. I may merge
both dma engine user of musb at some point but not just yet.

The driver seems to work in RX/TX mode in host mode, tested on mass
storage. I increaed the size of the TX / RX transfers and waited for the
core code to cancel a transfers and it seems to recover.

v2..3:
- use mall transfers on RX side and check data toggle.
- use rndis mode on tx side so we haveon interrupt for 4096 transfers.
- remove custom "transferred" hack and use dmaengine_tx_status() to
  compute the total amount of data that has been transferred.
- cancel transfers and reclaim descriptors

v1..v2:
- RX path added
- dma mode 0 & 1 is working
- device tree nodes re-created.

Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Dan Williams <djbw@fb.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Felipe Balbi <balbi@ti.com>

arch/arm/boot/dts/am335x-evm.dts

@@ -193,6 +193,10 @@ usb@47401000 {
 			usb@47401800 {
 				status = "okay";
 			};
+
+			dma@07402000  {
+				status = "okay";
+			};
 		};
 
 		i2c1: i2c@4802a000 {

arch/arm/boot/dts/am33xx.dtsi

@@ -383,6 +383,29 @@ musb0: usb@47401400 {
 					port-mode = <3>;
 					power = <250>;
 					phys = <&usb0_phy>;
+
+				dmas = <&cppi41dma  0 0 &cppi41dma  1 0
+					&cppi41dma  2 0 &cppi41dma  3 0
+					&cppi41dma  4 0 &cppi41dma  5 0
+					&cppi41dma  6 0 &cppi41dma  7 0
+					&cppi41dma  8 0 &cppi41dma  9 0
+					&cppi41dma 10 0 &cppi41dma 11 0
+					&cppi41dma 12 0 &cppi41dma 13 0
+					&cppi41dma 14 0 &cppi41dma  0 1
+					&cppi41dma  1 1 &cppi41dma  2 1
+					&cppi41dma  3 1 &cppi41dma  4 1
+					&cppi41dma  5 1 &cppi41dma  6 1
+					&cppi41dma  7 1 &cppi41dma  8 1
+					&cppi41dma  9 1 &cppi41dma 10 1
+					&cppi41dma 11 1 &cppi41dma 12 1
+					&cppi41dma 13 1 &cppi41dma 14 1>;
+				dma-names =
+					"rx1", "rx2", "rx3", "rx4", "rx5", "rx6", "rx7",
+					"rx8", "rx9", "rx10", "rx11", "rx12", "rx13",
+					"rx14", "rx15",
+					"tx1", "tx2", "tx3", "tx4", "tx5", "tx6", "tx7",
+					"tx8", "tx9", "tx10", "tx11", "tx12", "tx13",
+					"tx14", "tx15";
 				};
 			};
 
@@ -415,8 +438,46 @@ musb1: usb@47401c00 {
 					port-mode = <3>;
 					power = <250>;
 					phys = <&usb1_phy>;
+
+				dmas = <&cppi41dma 15 0 &cppi41dma 16 0
+					&cppi41dma 17 0 &cppi41dma 18 0
+					&cppi41dma 19 0 &cppi41dma 20 0
+					&cppi41dma 21 0 &cppi41dma 22 0
+					&cppi41dma 23 0 &cppi41dma 24 0
+					&cppi41dma 25 0 &cppi41dma 26 0
+					&cppi41dma 27 0 &cppi41dma 28 0
+					&cppi41dma 29 0 &cppi41dma 15 1
+					&cppi41dma 16 1 &cppi41dma 17 1
+					&cppi41dma 18 1 &cppi41dma 19 1
+					&cppi41dma 20 1 &cppi41dma 21 1
+					&cppi41dma 22 1 &cppi41dma 23 1
+					&cppi41dma 24 1 &cppi41dma 25 1
+					&cppi41dma 26 1 &cppi41dma 27 1
+					&cppi41dma 28 1 &cppi41dma 29 1>;
+				dma-names =
+					"rx1", "rx2", "rx3", "rx4", "rx5", "rx6", "rx7",
+					"rx8", "rx9", "rx10", "rx11", "rx12", "rx13",
+					"rx14", "rx15",
+					"tx1", "tx2", "tx3", "tx4", "tx5", "tx6", "tx7",
+					"tx8", "tx9", "tx10", "tx11", "tx12", "tx13",
+					"tx14", "tx15";
 				};
 			};
+
+			cppi41dma: dma@07402000 {
+				compatible = "ti,am3359-cppi41";
+				reg =  <0x47400000 0x1000
+					0x47402000 0x1000
+					0x47403000 0x1000
+					0x47404000 0x4000>;
+				reg-names = "glue controller scheduler queuemgr";
+				interrupts = <17>;
+				interrupt-names = "glue";
+				#dma-cells = <2>;
+				#dma-channels = <30>;
+				#dma-requests = <256>;
+				status = "disabled";
+			};
 		};
 
 		epwmss0: epwmss@48300000 {

drivers/dma/Kconfig

@@ -287,6 +287,14 @@ config DMA_OMAP
 	select DMA_ENGINE
 	select DMA_VIRTUAL_CHANNELS
 
+config TI_CPPI41
+	tristate "AM33xx CPPI41 DMA support"
+	depends on ARCH_OMAP
+	select DMA_ENGINE
+	help
+	  The Communications Port Programming Interface (CPPI) 4.1 DMA engine
+	  is currently used by the USB driver on AM335x platforms.
+
 config MMP_PDMA
 	bool "MMP PDMA support"
 	depends on (ARCH_MMP || ARCH_PXA)

drivers/dma/Makefile

@@ -39,3 +39,4 @@ obj-$(CONFIG_MMP_TDMA) += mmp_tdma.o
 obj-$(CONFIG_DMA_OMAP) += omap-dma.o
 obj-$(CONFIG_MMP_PDMA) += mmp_pdma.o
 obj-$(CONFIG_DMA_JZ4740) += dma-jz4740.o
+obj-$(CONFIG_TI_CPPI41) += cppi41.o

drivers/usb/musb/Kconfig

@@ -129,6 +129,10 @@ config USB_TI_CPPI_DMA
 	help
 	  Enable DMA transfers when TI CPPI DMA is available.
 
+config USB_TI_CPPI41_DMA
+	bool 'TI CPPI 4.1 (AM335x)'
+	depends on ARCH_OMAP
+
 config USB_TUSB_OMAP_DMA
 	bool 'TUSB 6010'
 	depends on USB_MUSB_TUSB6010

drivers/usb/musb/Makefile

@@ -32,3 +32,4 @@ musb_hdrc-$(CONFIG_USB_INVENTRA_DMA)		+= musbhsdma.o
 musb_hdrc-$(CONFIG_USB_TI_CPPI_DMA)		+= cppi_dma.o
 musb_hdrc-$(CONFIG_USB_TUSB_OMAP_DMA)		+= tusb6010_omap.o
 musb_hdrc-$(CONFIG_USB_UX500_DMA)		+= ux500_dma.o
+musb_hdrc-$(CONFIG_USB_TI_CPPI41_DMA)		+= musb_cppi41.o

drivers/usb/musb/musb_dma.h

@@ -68,7 +68,7 @@ struct musb_hw_ep;
 #define	is_dma_capable()	(1)
 #endif
 
-#ifdef CONFIG_USB_TI_CPPI_DMA
+#if defined(CONFIG_USB_TI_CPPI_DMA) || defined(CONFIG_USB_TI_CPPI41_DMA)
 #define	is_cppi_enabled()	1
 #else
 #define	is_cppi_enabled()	0