[v3,11/12] riscv: Add device tree for K210

Where possible, I have tried to find compatible drivers based on the layout of
registers. However, I have not tested most of this functionality, and most
devices should be considered descriptive at best. I would appreciate if anyone
could help identify possibly compatible devices, especially for the timers
and rtc.

Should the size of a reg be the size of the documented registers, or the size
of the address space which will be routed to that device?

Signed-off-by: Sean Anderson <seanga2@gmail.com>
---
  Changes for v3:
  - Move this patch to the end of the series
  - Add a max frequency for spi3
  - Remov unused compatible strings from spi-flash@0
  - Add s and u to isa string
  - Fix mmu-type
  - Remove cache-line size since it is unused (in u-boot) and undocumented
    (upstream)
  - Add timer interrupts to clint0
  - Round up various registers
  - Add riscv,max-priority to plic
  - Add apb* busses, since they have clocks which need to be enabled to access
    their devices
  - Change uart compatible strings to "snps,dw-apb-uart", since that appears to
    match their registers
  - Add compatible string for wdt*
  - Add system reset device under sysctl
  - Add reset device under sysctl
  Changes for v2:
  - Model changed to "Sipeed Maix Bit" to match file name
  - Value of stdout-path fixed
  - SD card slot compatible changed to "mmc-spi-slot"
  - "jedec,spi-nor" added to spi flash compatible list
  - Aliases for spi busses added
  - timebase-frequency divided by 50 to match timer speed
  - cpu-frequency renamed to clock-frequency
  - CPUX_intc restyled to cpuX_intc
  - "kendryte,k210-soc" added to soc compatible list for future-proofing
  - PLIC handle renamed to plic0 from pic0
  - K210_RST_SOC removed from sysrst, due to not being located in the
    reset register
  - K210_RST_* numbers changed to match their bit offset within the reset
    register
  - gpio_controller restyled to gpio-controller
  - Added a second clock to the dma binding to match what the driver expects
  - Changed "snps,designware-spi" compatible string to "snps,dw-apb-ssi" to
    match the correct driver
  - Added a name to the spi clocks
  - Added reg-io-width property to spi bindings
  - Assigned a default parent to K210_CLK_SPI3
  - Removed assigned clocks for ACLK and PLLs
  - Removed u-boot,dm-pre-reloc bindings

 arch/riscv/dts/Makefile                 |   1 +
 arch/riscv/dts/k210-maix-bit.dts        |  42 ++
 arch/riscv/dts/k210.dtsi                | 496 ++++++++++++++++++++++++
 include/dt-bindings/reset/k210-sysctl.h |  38 ++
 4 files changed, 577 insertions(+)
 create mode 100644 arch/riscv/dts/k210-maix-bit.dts
 create mode 100644 arch/riscv/dts/k210.dtsi
 create mode 100644 include/dt-bindings/reset/k210-sysctl.h

Hi Sean,

On Mon, Feb 3, 2020 at 4:10 AM Sean Anderson <seanga2@gmail.com> wrote:
>
> Where possible, I have tried to find compatible drivers based on the layout of
> registers. However, I have not tested most of this functionality, and most
> devices should be considered descriptive at best. I would appreciate if anyone
> could help identify possibly compatible devices, especially for the timers
> and rtc.
>
> Should the size of a reg be the size of the documented registers, or the size
> of the address space which will be routed to that device?

Perhaps we need use the size of the address space routed to that
device, in case there is some undocumented registers we need handle.

>
> Signed-off-by: Sean Anderson <seanga2@gmail.com>
> ---
>   Changes for v3:
>   - Move this patch to the end of the series
>   - Add a max frequency for spi3
>   - Remov unused compatible strings from spi-flash@0
>   - Add s and u to isa string
>   - Fix mmu-type
>   - Remove cache-line size since it is unused (in u-boot) and undocumented
>     (upstream)
>   - Add timer interrupts to clint0
>   - Round up various registers
>   - Add riscv,max-priority to plic
>   - Add apb* busses, since they have clocks which need to be enabled to access
>     their devices
>   - Change uart compatible strings to "snps,dw-apb-uart", since that appears to
>     match their registers
>   - Add compatible string for wdt*
>   - Add system reset device under sysctl
>   - Add reset device under sysctl
>   Changes for v2:
>   - Model changed to "Sipeed Maix Bit" to match file name
>   - Value of stdout-path fixed
>   - SD card slot compatible changed to "mmc-spi-slot"
>   - "jedec,spi-nor" added to spi flash compatible list
>   - Aliases for spi busses added
>   - timebase-frequency divided by 50 to match timer speed
>   - cpu-frequency renamed to clock-frequency
>   - CPUX_intc restyled to cpuX_intc
>   - "kendryte,k210-soc" added to soc compatible list for future-proofing
>   - PLIC handle renamed to plic0 from pic0
>   - K210_RST_SOC removed from sysrst, due to not being located in the
>     reset register
>   - K210_RST_* numbers changed to match their bit offset within the reset
>     register
>   - gpio_controller restyled to gpio-controller
>   - Added a second clock to the dma binding to match what the driver expects
>   - Changed "snps,designware-spi" compatible string to "snps,dw-apb-ssi" to
>     match the correct driver
>   - Added a name to the spi clocks
>   - Added reg-io-width property to spi bindings
>   - Assigned a default parent to K210_CLK_SPI3
>   - Removed assigned clocks for ACLK and PLLs
>   - Removed u-boot,dm-pre-reloc bindings
>
>  arch/riscv/dts/Makefile                 |   1 +
>  arch/riscv/dts/k210-maix-bit.dts        |  42 ++
>  arch/riscv/dts/k210.dtsi                | 496 ++++++++++++++++++++++++
>  include/dt-bindings/reset/k210-sysctl.h |  38 ++
>  4 files changed, 577 insertions(+)
>  create mode 100644 arch/riscv/dts/k210-maix-bit.dts
>  create mode 100644 arch/riscv/dts/k210.dtsi
>  create mode 100644 include/dt-bindings/reset/k210-sysctl.h
>
> diff --git a/arch/riscv/dts/Makefile b/arch/riscv/dts/Makefile
> index 4f30e6936f..3a6f96c67d 100644
> --- a/arch/riscv/dts/Makefile
> +++ b/arch/riscv/dts/Makefile
> @@ -2,6 +2,7 @@
>
>  dtb-$(CONFIG_TARGET_AX25_AE350) += ae350_32.dtb ae350_64.dtb
>  dtb-$(CONFIG_TARGET_SIFIVE_FU540) += hifive-unleashed-a00.dtb
> +dtb-$(CONFIG_TARGET_SIPEED_MAIX) += k210-maix-bit.dtb
>
>  targets += $(dtb-y)
>
> diff --git a/arch/riscv/dts/k210-maix-bit.dts b/arch/riscv/dts/k210-maix-bit.dts
> new file mode 100644
> index 0000000000..10f36921e0
> --- /dev/null
> +++ b/arch/riscv/dts/k210-maix-bit.dts
> @@ -0,0 +1,42 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Copyright (C) 2019 Sean Anderson <seanga2@gmail.com>
> + */
> +
> +/dts-v1/;
> +
> +#include "k210.dtsi"
> +
> +/ {
> +       model = "Sipeed Maix Bit";
> +       compatible = "sipeed,maix-bit", "kendryte,k210";
> +
> +       chosen {
> +               stdout-path = "serial0:115200";
> +       };
> +};
> +
> +&uarths0 {
> +       status = "okay";
> +};
> +
> +&spi0 {
> +       status = "okay";
> +       slot@0 {
> +               compatible = "mmc-spi-slot";
> +               reg = <0>;
> +               broken-cd;
> +               disable-wp;
> +       };
> +};
> +
> +&spi3 {
> +       status = "okay";
> +       spi-max-frequency = <120000000>;
> +       spi-flash@0 {
> +               compatible = "jedec,spi-nor";
> +               reg = <0>;
> +               spi-max-frequency = <120000000>;
> +               m25p,fast-read;
> +       };
> +};
> diff --git a/arch/riscv/dts/k210.dtsi b/arch/riscv/dts/k210.dtsi
> new file mode 100644
> index 0000000000..cc46b692e6
> --- /dev/null
> +++ b/arch/riscv/dts/k210.dtsi
> @@ -0,0 +1,496 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Copyright (C) 2019 Sean Anderson <seanga2@gmail.com>
> + */
> +
> +#include <dt-bindings/clock/k210-sysctl.h>
> +#include <dt-bindings/mfd/k210-sysctl.h>
> +#include <dt-bindings/reset/k210-sysctl.h>
> +
> +/ {
> +       /*
> +        * Although the K210 is a 64-bit CPU, the address bus is only 32-bits
> +        * wide, and the upper half of all addresses is ignored.
> +        */
> +       #address-cells = <1>;
> +       #size-cells = <1>;
> +       compatible = "kendryte,k210";
> +
> +       aliases {
> +               serial0 = &uarths0;
> +               serial1 = &uart1;
> +               serial2 = &uart2;
> +               serial3 = &uart3;
> +               spi0 = &spi0;
> +               spi1 = &spi1;
> +               spi2 = &spi2;
> +               spi3 = &spi3;
> +       };
> +
> +       clocks {
> +               in0: oscillator {
> +                       compatible = "fixed-clock";
> +                       #clock-cells = <0>;
> +                       clock-frequency = <26000000>;
> +               };
> +       };
> +
> +       cpus {
> +               #address-cells = <1>;
> +               #size-cells = <0>;
> +               timebase-frequency = <7800000>;
> +               cpu0: cpu@0 {
> +                       device_type = "cpu";
> +                       reg = <0>;
> +                       compatible = "riscv";
> +                       riscv,isa = "rv64acdfimsu";
> +                       mmu-type = "sv39";
> +                       i-cache-size = <0x8000>;
> +                       d-cache-size = <0x8000>;
> +                       clocks = <&sysclk K210_CLK_CPU>;
> +                       clock-frequency = <390000000>;

I wonder there is already clocks property, why do we have another
clock-frequency property to provide duplicated information?

> +                       cpu0_intc: interrupt-controller {
> +                               #interrupt-cells = <1>;
> +                               interrupt-controller;
> +                               compatible = "riscv,cpu-intc";
> +                       };
> +               };
> +               cpu1: cpu@1 {
> +                       device_type = "cpu";
> +                       reg = <1>;
> +                       compatible = "riscv";
> +                       riscv,isa = "rv64acdfimsu";
> +                       mmu-type = "sv39";
> +                       i-cache-size = <0x8000>;
> +                       d-cache-size = <0x8000>;
> +                       clocks = <&sysclk K210_CLK_CPU>;
> +                       clock-frequency = <390000000>;
> +                       cpu1_intc: interrupt-controller {
> +                               #interrupt-cells = <1>;
> +                               interrupt-controller;
> +                               compatible = "riscv,cpu-intc";
> +                       };
> +               };
> +       };
> +
> +       sram0: memory@80000000 {
> +               device_type = "memory";
> +               reg = <0x80000000 0x400000>;
> +               clocks = <&sysclk K210_CLK_SRAM0>;
> +       };
> +
> +       sram1: memory@80400000 {
> +               device_type = "memory";
> +               reg = <0x80400000 0x400000>;
> +               clocks = <&sysclk K210_CLK_SRAM1>;
> +       };
> +
> +       reserved-memory {
> +               #address-cells = <1>;
> +               #size-cells = <1>;
> +               ranges;
> +
> +               ai_reserved: ai@80600000 {
> +                       reg = <0x80600000 0x200000>;
> +                       reusable;
> +               };
> +       };
> +
> +       soc {
> +               #address-cells = <1>;
> +               #size-cells = <1>;
> +               compatible = "kendryte,k210-soc", "simple-bus";
> +               ranges;
> +               interrupt-parent = <&plic0>;
> +
> +               clint0: interrupt-controller@2000000 {
> +                       compatible = "riscv,clint0";
> +                       reg = <0x2000000 0x1000>;
> +                       interrupts-extended = <&cpu0_intc 3>, <&cpu0_intc 7>,
> +                                             <&cpu1_intc 3>, <&cpu1_intc 7>;
> +                       clocks = <&sysclk K210_CLK_CPU>;
> +               };
> +
> +               plic0: interrupt-controller@c000000 {
> +                       #interrupt-cells = <1>;
> +                       interrupt-controller;
> +                       compatible = "kendryte,k210-plic", "riscv,plic1";
> +                       reg = <0xC000000 0x4000000>;
> +                       interrupts-extended = <&cpu0_intc 9>, <&cpu0_intc 11>,
> +                                             <&cpu1_intc 9>, <&cpu1_intc 11>;
> +                       riscv,ndev = <65>;
> +                       riscv,max-priority = <7>;
> +               };
> +

[snip]

Regards,
Bin

On 2/4/20 6:32 AM, Bin Meng wrote:
> Hi Sean,
> 
> On Mon, Feb 3, 2020 at 4:10 AM Sean Anderson <seanga2@gmail.com> wrote:
>>
>> Where possible, I have tried to find compatible drivers based on the layout of
>> registers. However, I have not tested most of this functionality, and most
>> devices should be considered descriptive at best. I would appreciate if anyone
>> could help identify possibly compatible devices, especially for the timers
>> and rtc.
>>
>> Should the size of a reg be the size of the documented registers, or the size
>> of the address space which will be routed to that device?
> 
> Perhaps we need use the size of the address space routed to that
> device, in case there is some undocumented registers we need handle.

Ok, I'll go with the whole address space then.

>> diff --git a/arch/riscv/dts/k210.dtsi b/arch/riscv/dts/k210.dtsi
>> new file mode 100644
>> index 0000000000..cc46b692e6
>> --- /dev/null
>> +++ b/arch/riscv/dts/k210.dtsi
>> @@ -0,0 +1,496 @@
>> +// SPDX-License-Identifier: GPL-2.0+
>> +/*
>> + * Copyright (C) 2019 Sean Anderson <seanga2@gmail.com>
>> + */
>> +
>> +#include <dt-bindings/clock/k210-sysctl.h>
>> +#include <dt-bindings/mfd/k210-sysctl.h>
>> +#include <dt-bindings/reset/k210-sysctl.h>
>> +
>> +/ {
>> +       /*
>> +        * Although the K210 is a 64-bit CPU, the address bus is only 32-bits
>> +        * wide, and the upper half of all addresses is ignored.
>> +        */
>> +       #address-cells = <1>;
>> +       #size-cells = <1>;
>> +       compatible = "kendryte,k210";
>> +
>> +       aliases {
>> +               serial0 = &uarths0;
>> +               serial1 = &uart1;
>> +               serial2 = &uart2;
>> +               serial3 = &uart3;
>> +               spi0 = &spi0;
>> +               spi1 = &spi1;
>> +               spi2 = &spi2;
>> +               spi3 = &spi3;
>> +       };
>> +
>> +       clocks {
>> +               in0: oscillator {
>> +                       compatible = "fixed-clock";
>> +                       #clock-cells = <0>;
>> +                       clock-frequency = <26000000>;
>> +               };
>> +       };
>> +
>> +       cpus {
>> +               #address-cells = <1>;
>> +               #size-cells = <0>;
>> +               timebase-frequency = <7800000>;
>> +               cpu0: cpu@0 {
>> +                       device_type = "cpu";
>> +                       reg = <0>;
>> +                       compatible = "riscv";
>> +                       riscv,isa = "rv64acdfimsu";
>> +                       mmu-type = "sv39";
>> +                       i-cache-size = <0x8000>;
>> +                       d-cache-size = <0x8000>;
>> +                       clocks = <&sysclk K210_CLK_CPU>;
>> +                       clock-frequency = <390000000>;
> 
> I wonder there is already clocks property, why do we have another
> clock-frequency property to provide duplicated information?

This is for compatibility with the existing riscv cpu driver. There is a
patch [1] to move the driver over to using clocks, but I think you
already expressed that it should be merged into this series (not as a
separate series).

[1] https://patchwork.ozlabs.org/project/uboot/list/?series=156381

--Sean

Hi Sean,

On Tue, Feb 4, 2020 at 10:23 PM Sean Anderson <seanga2@gmail.com> wrote:
>
> On 2/4/20 6:32 AM, Bin Meng wrote:
> > Hi Sean,
> >
> > On Mon, Feb 3, 2020 at 4:10 AM Sean Anderson <seanga2@gmail.com> wrote:
> >>
> >> Where possible, I have tried to find compatible drivers based on the layout of
> >> registers. However, I have not tested most of this functionality, and most
> >> devices should be considered descriptive at best. I would appreciate if anyone
> >> could help identify possibly compatible devices, especially for the timers
> >> and rtc.
> >>
> >> Should the size of a reg be the size of the documented registers, or the size
> >> of the address space which will be routed to that device?
> >
> > Perhaps we need use the size of the address space routed to that
> > device, in case there is some undocumented registers we need handle.
>
> Ok, I'll go with the whole address space then.
>
> >> diff --git a/arch/riscv/dts/k210.dtsi b/arch/riscv/dts/k210.dtsi
> >> new file mode 100644
> >> index 0000000000..cc46b692e6
> >> --- /dev/null
> >> +++ b/arch/riscv/dts/k210.dtsi
> >> @@ -0,0 +1,496 @@
> >> +// SPDX-License-Identifier: GPL-2.0+
> >> +/*
> >> + * Copyright (C) 2019 Sean Anderson <seanga2@gmail.com>
> >> + */
> >> +
> >> +#include <dt-bindings/clock/k210-sysctl.h>
> >> +#include <dt-bindings/mfd/k210-sysctl.h>
> >> +#include <dt-bindings/reset/k210-sysctl.h>
> >> +
> >> +/ {
> >> +       /*
> >> +        * Although the K210 is a 64-bit CPU, the address bus is only 32-bits
> >> +        * wide, and the upper half of all addresses is ignored.
> >> +        */
> >> +       #address-cells = <1>;
> >> +       #size-cells = <1>;
> >> +       compatible = "kendryte,k210";
> >> +
> >> +       aliases {
> >> +               serial0 = &uarths0;
> >> +               serial1 = &uart1;
> >> +               serial2 = &uart2;
> >> +               serial3 = &uart3;
> >> +               spi0 = &spi0;
> >> +               spi1 = &spi1;
> >> +               spi2 = &spi2;
> >> +               spi3 = &spi3;
> >> +       };
> >> +
> >> +       clocks {
> >> +               in0: oscillator {
> >> +                       compatible = "fixed-clock";
> >> +                       #clock-cells = <0>;
> >> +                       clock-frequency = <26000000>;
> >> +               };
> >> +       };
> >> +
> >> +       cpus {
> >> +               #address-cells = <1>;
> >> +               #size-cells = <0>;
> >> +               timebase-frequency = <7800000>;
> >> +               cpu0: cpu@0 {
> >> +                       device_type = "cpu";
> >> +                       reg = <0>;
> >> +                       compatible = "riscv";
> >> +                       riscv,isa = "rv64acdfimsu";
> >> +                       mmu-type = "sv39";
> >> +                       i-cache-size = <0x8000>;
> >> +                       d-cache-size = <0x8000>;
> >> +                       clocks = <&sysclk K210_CLK_CPU>;
> >> +                       clock-frequency = <390000000>;
> >
> > I wonder there is already clocks property, why do we have another
> > clock-frequency property to provide duplicated information?
>
> This is for compatibility with the existing riscv cpu driver. There is a
> patch [1] to move the driver over to using clocks, but I think you
> already expressed that it should be merged into this series (not as a
> separate series).

Yes, so with that 2 patches in this same series, we no longer need
clock-frequency.

>
> [1] https://patchwork.ozlabs.org/project/uboot/list/?series=156381

Regards,
Bin