[PATCH v3] ARM: dts: at91: sama5d2: add m_can nodes

[Wenyou Yang]

Add nodes to support the Controller Area Network(M_CAN) on SAMA5D2.
The version of M_CAN IP core is 3.1.0 (CREL = 0x31040730).

As said in SAMA5D2 datasheet, the CAN clock is recommended to use
frequencies of 20, 40 or 80 MHz. To achieve these frequencies,
PMC GCLK3 must select the UPLLCK(480 MHz) as source clock and
divide by 24, 12, or 6. So, the "assigned-clock-rates" property
has three options: 20000000, 40000000, and 80000000.
The "assigned-clock-parents" property should be referred to utmi
fixedly.

The MSBs [bits 31:16] of the CAN Message RAM for CAN0 and CAN1 are
default configured in 0x00200000. To avoid conflict with SRAM map
for PM, change them to 0x00210000 in the AT91Bootstrap via setting
the CAN Memories Address-based Register(SFR_CAN) of SFR.

Signed-off-by: Wenyou Yang <wenyou.yang at atmel.com>
Tested-by: Quentin Schulz <quentin.schulz at free-electrons.com>
---
The patch is tested on SAMA5D2 Xplained and based on the patch set,
 1. [PATCH v4 1/7] can: m_can: Disabled Interrupt Line 1
    http://marc.info/?l=linux-can&m=149165343604033&w=2

Changes in v3:
 - Add Tested-by tag.
 - Change the number of Rx Rx Buffers, Tx Buffers and Tx Event FIFO
   to maximum.

Changes in v2:
 - Configures 10 TX Event FIFO elements and 10 TX Buffers/FIFO slots,
   because the TXE FIFO is needed to be configured.
 - Configure the offset of Message RAM for CAN1 followed from CAN0's.

 arch/arm/boot/dts/at91-sama5d2_xplained.dts | 24 +++++++++++++
 arch/arm/boot/dts/sama5d2.dtsi              | 56 +++++++++++++++++++++++++++++
 2 files changed, 80 insertions(+)

diff --git a/arch/arm/boot/dts/at91-sama5d2_xplained.dts b/arch/arm/boot/dts/at91-sama5d2_xplained.dts
index 9f7f8a7d8ff9..2f19b08dc226 100644
--- a/arch/arm/boot/dts/at91-sama5d2_xplained.dts
+++ b/arch/arm/boot/dts/at91-sama5d2_xplained.dts
@@ -257,6 +257,12 @@
 				status = "okay";
 			};
 
+			can0: can at f8054000 {
+				pinctrl-names = "default";
+				pinctrl-0 = <&pinctrl_can0_default>;
+				status = "okay";
+			};
+
 			uart3: serial at fc008000 {
 				atmel,use-dma-rx;
 				atmel,use-dma-tx;
@@ -321,6 +327,18 @@
 					bias-disable;
 				};
 
+				pinctrl_can0_default: can0_default {
+					pinmux = <PIN_PC10__CANTX0>,
+						 <PIN_PC11__CANRX0>;
+					bias-disable;
+				};
+
+				pinctrl_can1_default: can1_default {
+					pinmux = <PIN_PC26__CANTX1>,
+						 <PIN_PC27__CANRX1>;
+					bias-disable;
+				};
+
 				pinctrl_charger_chglev: charger_chglev {
 					pinmux = <PIN_PA12__GPIO>;
 					bias-disable;
@@ -468,6 +486,12 @@
 				};
 
 			};
+
+			can1: can at fc050000 {
+				pinctrl-names = "default";
+				pinctrl-0 = <&pinctrl_can1_default>;
+				status = "okay";
+			};
 		};
 	};
 
diff --git a/arch/arm/boot/dts/sama5d2.dtsi b/arch/arm/boot/dts/sama5d2.dtsi
index 22332be72140..7e00fa21373e 100644
--- a/arch/arm/boot/dts/sama5d2.dtsi
+++ b/arch/arm/boot/dts/sama5d2.dtsi
@@ -762,6 +762,18 @@
 						atmel,clk-output-range = <0 83000000>;
 					};
 
+					can0_clk: can0_clk {
+						#clock-cells = <0>;
+						reg = <56>;
+						atmel,clk-output-range = <0 83000000>;
+					};
+
+					can1_clk: can1_clk {
+						#clock-cells = <0>;
+						reg = <57>;
+						atmel,clk-output-range = <0 83000000>;
+					};
+
 					classd_clk: classd_clk {
 						#clock-cells = <0>;
 						reg = <59>;
@@ -890,6 +902,18 @@
 						#clock-cells = <0>;
 						reg = <55>;
 					};
+
+					can0_gclk: can0_gclk {
+						#clock-cells = <0>;
+						reg = <56>;
+						atmel,clk-output-range = <0 80000000>;
+					};
+
+					can1_gclk: can1_gclk {
+						#clock-cells = <0>;
+						reg = <57>;
+						atmel,clk-output-range = <0 80000000>;
+					};
 				};
 			};
 
@@ -1144,6 +1168,22 @@
 				clocks = <&clk32k>;
 			};
 
+			can0: can at f8054000 {
+				compatible = "bosch,m_can";
+				reg = <0xf8054000 0x4000>, <0x210000 0x4000>;
+				reg-names = "m_can", "message_ram";
+				interrupts = <56 IRQ_TYPE_LEVEL_HIGH 7>,
+					     <64 IRQ_TYPE_LEVEL_HIGH 7>;
+				interrupt-names = "int0", "int1";
+				clocks = <&can0_clk>, <&can0_gclk>;
+				clock-names = "hclk", "cclk";
+				assigned-clocks = <&can0_gclk>;
+				assigned-clock-parents = <&utmi>;
+				assigned-clock-rates = <40000000>;
+				bosch,mram-cfg = <0x0 0 0 64 0 0 32 32>;
+				status = "disabled";
+			};
+
 			spi1: spi at fc000000 {
 				compatible = "atmel,at91rm9200-spi";
 				reg = <0xfc000000 0x100>;
@@ -1305,6 +1345,22 @@
 				status = "okay";
 			};
 
+			can1: can at fc050000 {
+				compatible = "bosch,m_can";
+				reg = <0xfc050000 0x4000>, <0x210000 0x4000>;
+				reg-names = "m_can", "message_ram";
+				interrupts = <57 IRQ_TYPE_LEVEL_HIGH 7>,
+					     <65 IRQ_TYPE_LEVEL_HIGH 7>;
+				interrupt-names = "int0", "int1";
+				clocks = <&can1_clk>, <&can1_gclk>;
+				clock-names = "hclk", "cclk";
+				assigned-clocks = <&can1_gclk>;
+				assigned-clock-parents = <&utmi>;
+				assigned-clock-rates = <40000000>;
+				bosch,mram-cfg = <0x1100 0 0 64 0 0 32 32>;
+				status = "disabled";
+			};
+
 			chipid at fc069000 {
 				compatible = "atmel,sama5d2-chipid";
 				reg = <0xfc069000 0x8>;
-- 
2.11.0