Re: [PATCH v2] ARM: dts: at91: sama5d2: add m_can nodes

From: Quentin Schulz
Date: Wed Apr 19 2017 - 09:07:50 EST


Hi,

On 19/04/2017 10:46, Wenyou Yang wrote:
> 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@xxxxxxxxx>
> ---
> 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 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.
>


I've tested with the v4 patch series of Mario Hüttel on a SAMA5D2
Xplained and did the following:

# ip link set can0 down
# ip link set can0 up type can bitrate 125000
# cansend can0 500#1E.10.10

Last line at least 10 times, every message is received on my computer.
Same with can1. Tested with candump can0 as well, everything looks fine.

Tested-by: Quentin Schulz <quentin.schulz@xxxxxxxxxxxxxxxxxx>

Thanks,
Quentin


> 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@f8054000 {
> + pinctrl-names = "default";
> + pinctrl-0 = <&pinctrl_can0_default>;
> + status = "okay";
> + };
> +
> uart3: serial@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@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..383ca9307edf 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@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 32 0 0 10 10>;
> + status = "disabled";
> + };
> +
> spi1: spi@fc000000 {
> compatible = "atmel,at91rm9200-spi";
> reg = <0xfc000000 0x100>;
> @@ -1305,6 +1345,22 @@
> status = "okay";
> };
>
> + can1: can@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 32 0 0 10 10>;
> + status = "disabled";
> + };
> +
> chipid@fc069000 {
> compatible = "atmel,sama5d2-chipid";
> reg = <0xfc069000 0x8>;
>

--
Quentin Schulz, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com