Re: [PATCH V3] arm64: amd-seattle: Adding device tree for AMD Seattle platform

From: Arnd Bergmann
Date: Thu Nov 13 2014 - 06:30:24 EST


On Tuesday 28 October 2014 08:36:54 suravee.suthikulpanit@xxxxxxx wrote:
> From: Suravee Suthikulpanit <Suravee.Suthikulpanit@xxxxxxx>
>
> Initial revision of device tree for AMD Seattle platform

Sorry for not looking at this earlier in enough detail.

> + dma0: dma@0500000 {
> + compatible = "arm,pl330", "arm,primecell";
> + reg = <0 0x0500000 0 0x1000>;
> + interrupts =
> + <0 368 4>,
> + <0 369 4>,
> + <0 370 4>,
> + <0 371 4>,
> + <0 372 4>,
> + <0 373 4>,
> + <0 374 4>,
> + <0 375 4>;
> + clocks = <&dmaclk_500mhz>;
> + clock-names = "apb_pclk";
> + #dma-cells = <1>;
> + };

Is this device cache-coherent?

Does it support larger than 32-bit DMA addresses?

> + sata0: sata@00300000 {
> + compatible = "snps,dwc-ahci";
> + reg = <0 0x300000 0 0x800>;
> + interrupts = <0 355 4>;
> + clocks = <&sataclk_333mhz>;
> + clock-names = "apb_pclk";
> + dma-coherent;
> + };

Same here: you list it as coherent, but not 64-bit DMA capable.
Is that intentional?

> + i2c@1000000 {
> + compatible = "snps,designware-i2c";
> + reg = <0 0x01000000 0 0x1000>;
> + interrupts = <0 357 4>;
> + clocks = <&uartspiclk_100mhz>;
> + clock-names = "apb_pclk";
> + };
> +
> + serial0: serial@1010000 {
> + compatible = "arm,pl011", "arm,primecell";
> + reg = <0 0x1010000 0 0x1000>;
> + interrupts = <0 328 4>;
> + clocks = <&uartspiclk_100mhz>, <&uartspiclk_100mhz>;
> + clock-names = "uartclk", "apb_pclk";
> + };
> +
> + ssp@1020000 {
> + compatible = "arm,pl022", "arm,primecell";
> + #gpio-cells = <2>;
> + reg = <0 0x1020000 0 0x1000>;
> + spi-controller;
> + interrupts = <0 330 4>;
> + clocks = <&uartspiclk_100mhz>;
> + clock-names = "apb_pclk";
> + };

Should these three be connected to the DMA engine?

> + ccp: ccp@00100000 {
> + compatible = "amd,ccp-seattle-v1a";
> + reg = <0 0x00100000 0 0x10000>;
> + interrupts = <0 3 4>;
> + dma-coherent;
> + };

I see the driver hacks an 48-bit DMA mask into this one.
Please fix the driver and add an appropriate dma-ranges property.

> + /* This entry is modified by UEFI */

Can you explain which parts are modified by UEFI?

> + pcie0: pcie-controller{
> + compatible = "pci-host-ecam-generic";
> + #address-cells = <3>;
> + #size-cells = <2>;
> + device_type = "pci";
> + bus-range = <0 0xff>;
> + reg = <0 0xf0000000 0 0x10000000>;
> + dma-coherent;
> + msi-parent = <&v2m0>;

This surely needs a dma-ranges property to allow larger than 32-bit DMA.



> + interrupts =
> + <0 320 4>, /* ioc_soc_serr */
> + <0 321 4>; /* ioc_soc_sci */

The pci-host-ecam-generic binding does not allow an interrupts property.

You seem to be missing an interrupt-map property.


> + ranges =
> + /* I/O Memory (size=64K) */
> + <0x01000000 0x00 0xefff0000 0x00 0xefff0000 0x00 0x00010000>,

Are you able to map the I/O space to bus address zero instead in the
firmware? This looks like a firmware bug, I/O space should not
be identity-mapped but is normally expected to have low port numbers.

> + /* Non-Pref 32-bit MMIO (size=512M) */
> + <0x02000000 0x00 0x40000000 0x00 0x40000000 0x00 0x20000000>,
> +
> + /* Non-Pref 32-bit MMIO (size=512M) */
> + <0x02000000 0x00 0x60000000 0x00 0x60000000 0x00 0x20000000>,
> +
> + /* Non-Pref 32-bit MMIO (size=512M) */
> + <0x02000000 0x00 0x80000000 0x00 0x80000000 0x00 0x20000000>,
> +
> + /* Non-Pref 32-bit MMIO (size=512M) */
> + <0x02000000 0x00 0xa0000000 0x00 0xa0000000 0x00 0x20000000>,

I don't understand why you use distinct ranges here and below. These are all
contiguous, so why not collapse them into one logical range.

> + smb {
> + compatible = "simple-bus";
> + #address-cells = <2>;
> + #size-cells = <2>;
> + ranges = <0 0 0 0xE0000000 0 0x01300000>;
> +
> + /include/ "amd-seattle-periph.dtsi"
> + };

I would put the smb node into the other file and move the include statement to the
top level.

Please use lowercase characters for the address.

Arnd
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/