Blackfin: bf54x: add kconfig for UART2/3 DMA channel assignments

The BF54x lacks dedicated DMA channels for the UART peripherals and need
to be muxed between others.  So add a kconfig option so people can select
which channels the UARTs will use so they can pick between SPORTs and the
less commonly used EPPI/PIXC peripherals.

Signed-off-by: steven miao <realmz6@gmail.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>

3 files changed, 83 insertions, 8 deletions

diff --git a/arch/blackfin/mach-bf548/Kconfig b/arch/blackfin/mach-bf548/Kconfig
index 70189a0d1a1..94acb586832 100644
--- a/arch/blackfin/mach-bf548/Kconfig
+++ b/arch/blackfin/mach-bf548/Kconfig
@@ -42,6 +42,65 @@ config BF548_ATAPI_ALTERNATIVE_PORT
 	  async address or GPIO port F and G. Select y to route it
 	  to GPIO.
 
+choice
+	prompt "UART2 DMA channel selection"
+	depends on SERIAL_BFIN_UART2
+	default UART2_DMA_RX_ON_DMA18
+	help
+		UART2 DMA channel selection
+		RX -> DMA18
+		TX -> DMA19
+		or
+		RX -> DMA13
+		TX -> DMA14
+
+config UART2_DMA_RX_ON_DMA18
+	bool "UART2 DMA RX -> DMA18 TX -> DMA19"
+	help
+		UART2 DMA channel assignment
+		RX -> DMA18
+		TX -> DMA19
+		use SPORT2 default DMA channel
+
+config UART2_DMA_RX_ON_DMA13
+	bool "UART2 DMA RX -> DMA13 TX -> DMA14"
+	help
+		UART2 DMA channel assignment
+		RX -> DMA13
+		TX -> DMA14
+		use EPPI1 EPPI2 default DMA channel
+endchoice
+
+choice
+	prompt "UART3 DMA channel selection"
+	depends on SERIAL_BFIN_UART3
+	default UART3_DMA_RX_ON_DMA20
+	help
+		UART3 DMA channel selection
+		RX -> DMA20
+		TX -> DMA21
+		or
+		RX -> DMA15
+		TX -> DMA16
+
+config UART3_DMA_RX_ON_DMA20
+	bool "UART3 DMA RX -> DMA20 TX -> DMA21"
+	help
+		UART3 DMA channel assignment
+		RX -> DMA20
+		TX -> DMA21
+		use SPORT3 default DMA channel
+
+config UART3_DMA_RX_ON_DMA15
+	bool "UART3 DMA RX -> DMA15 TX -> DMA16"
+	help
+		UART3 DMA channel assignment
+		RX -> DMA15
+		TX -> DMA16
+		use PIXC default DMA channel
+
+endchoice
+
 comment "Interrupt Priority Assignment"
 menu "Priority"
 
diff --git a/arch/blackfin/mach-bf548/include/mach/dma.h b/arch/blackfin/mach-bf548/include/mach/dma.h
index a30d242c739..1a1091b071f 100644
--- a/arch/blackfin/mach-bf548/include/mach/dma.h
+++ b/arch/blackfin/mach-bf548/include/mach/dma.h
@@ -27,17 +27,37 @@
 #define CH_PIXC_OVERLAY		16
 #define CH_PIXC_OUTPUT		17
 #define CH_SPORT2_RX		18
-#define CH_UART2_RX		18
 #define CH_SPORT2_TX		19
-#define CH_UART2_TX		19
 #define CH_SPORT3_RX		20
-#define CH_UART3_RX		20
 #define CH_SPORT3_TX		21
-#define CH_UART3_TX		21
 #define CH_SDH			22
 #define CH_NFC			22
 #define CH_SPI2			23
 
+#if defined(CONFIG_UART2_DMA_RX_ON_DMA13)
+#define CH_UART2_RX		13
+#define IRQ_UART2_RX		BFIN_IRQ(37)	/* UART2 RX USE EPP1 (DMA13) Interrupt */
+#define CH_UART2_TX		14
+#define IRQ_UART2_TX		BFIN_IRQ(38)	/* UART2 RX USE EPP1 (DMA14) Interrupt */
+#else						/* Default USE SPORT2's DMA Channel */
+#define CH_UART2_RX		18
+#define IRQ_UART2_RX		BFIN_IRQ(33)	/* UART2 RX (DMA18) Interrupt */
+#define CH_UART2_TX		19
+#define IRQ_UART2_TX		BFIN_IRQ(34)	/* UART2 TX (DMA19) Interrupt */
+#endif
+
+#if defined(CONFIG_UART3_DMA_RX_ON_DMA15)
+#define CH_UART3_RX		15
+#define IRQ_UART3_RX		BFIN_IRQ(64)	/* UART3 RX USE PIXC IN0 (DMA15) Interrupt */
+#define CH_UART3_TX		16
+#define IRQ_UART3_TX		BFIN_IRQ(65)	/* UART3 TX USE PIXC IN1 (DMA16) Interrupt */
+#else						/* Default USE SPORT3's DMA Channel */
+#define CH_UART3_RX		20
+#define IRQ_UART3_RX		BFIN_IRQ(35)	/* UART3 RX (DMA20) Interrupt */
+#define CH_UART3_TX		21
+#define IRQ_UART3_TX		BFIN_IRQ(36)	/* UART3 TX (DMA21) Interrupt */
+#endif
+
 #define CH_MEM_STREAM0_DEST	24
 #define CH_MEM_STREAM0_SRC	25
 #define CH_MEM_STREAM1_DEST	26
diff --git a/arch/blackfin/mach-bf548/include/mach/irq.h b/arch/blackfin/mach-bf548/include/mach/irq.h
index 99fd1b2c53d..7f87787e773 100644
--- a/arch/blackfin/mach-bf548/include/mach/irq.h
+++ b/arch/blackfin/mach-bf548/include/mach/irq.h
@@ -74,13 +74,9 @@ Events         (highest priority)  EMU         0
 #define IRQ_UART2_ERROR		BFIN_IRQ(31)	/* UART2 Status (Error) Interrupt */
 #define IRQ_CAN0_ERROR		BFIN_IRQ(32)	/* CAN0 Status (Error) Interrupt */
 #define IRQ_SPORT2_RX		BFIN_IRQ(33)	/* SPORT2 RX (DMA18) Interrupt */
-#define IRQ_UART2_RX		BFIN_IRQ(33)	/* UART2 RX (DMA18) Interrupt */
 #define IRQ_SPORT2_TX		BFIN_IRQ(34)	/* SPORT2 TX (DMA19) Interrupt */
-#define IRQ_UART2_TX		BFIN_IRQ(34)	/* UART2 TX (DMA19) Interrupt */
 #define IRQ_SPORT3_RX		BFIN_IRQ(35)	/* SPORT3 RX (DMA20) Interrupt */
-#define IRQ_UART3_RX		BFIN_IRQ(35)	/* UART3 RX (DMA20) Interrupt */
 #define IRQ_SPORT3_TX		BFIN_IRQ(36)	/* SPORT3 TX (DMA21) Interrupt */
-#define IRQ_UART3_TX		BFIN_IRQ(36)	/* UART3 TX (DMA21) Interrupt */
 #define IRQ_EPPI1		BFIN_IRQ(37)	/* EPP1 (DMA13) Interrupt */
 #define IRQ_EPPI2		BFIN_IRQ(38)	/* EPP2 (DMA14) Interrupt */
 #define IRQ_SPI1		BFIN_IRQ(39)	/* SPI1 (DMA5) Interrupt */