Re: [PATCH] dra7: sata: Fix SATA with CONFIG_ARM_LPAE enabled

From: Tony Lindgren
Date: Wed Mar 04 2020 - 11:21:03 EST


* Roger Quadros <rogerq@xxxxxx> [200304 09:01]:
> Even though the TRM says that SATA IP has 36 address bits
> wired in the SoC, we see bus errors whenever any address
> greater than 32-bit is given to the controller.
>
> This happens on dra7-EVM with 4G of RAM with CONFIG_ARM_LPAE=y.
>
> As a workaround we limit the DMA address range to 32-bits
> for SATA.
>
> Cc: Christoph Hellwig <hch@xxxxxx>
> Cc: Robin Murphy <robin.murphy@xxxxxxx>
> Cc: Rob Herring <robh+dt@xxxxxxxxxx>
> Reported-by: Yan Liu <yan-liu@xxxxxx>
> Signed-off-by: Roger Quadros <rogerq@xxxxxx>
> ---
>
> NOTE: Currently ARM dma-mapping code doesn't account for devices
> bus_dma_limit. This is fixed in [1].
>
> [1] https://lkml.org/lkml/2020/2/18/712

So is this dts patch safe to apply without the series above?

And should this dts patch be applied as a fix or can it wait
until the merge window?

Regards,

Tony

> arch/arm/boot/dts/dra7.dtsi | 25 ++++++++++++++++---------
> 1 file changed, 16 insertions(+), 9 deletions(-)
>
> diff --git a/arch/arm/boot/dts/dra7.dtsi b/arch/arm/boot/dts/dra7.dtsi
> index d78b684e7fca..895462c22d1c 100644
> --- a/arch/arm/boot/dts/dra7.dtsi
> +++ b/arch/arm/boot/dts/dra7.dtsi
> @@ -642,15 +642,22 @@
> };
>
> /* OCP2SCP3 */
> - sata: sata@4a141100 {
> - compatible = "snps,dwc-ahci";
> - reg = <0x4a140000 0x1100>, <0x4a141100 0x7>;
> - interrupts = <GIC_SPI 49 IRQ_TYPE_LEVEL_HIGH>;
> - phys = <&sata_phy>;
> - phy-names = "sata-phy";
> - clocks = <&l3init_clkctrl DRA7_L3INIT_SATA_CLKCTRL 8>;
> - ti,hwmods = "sata";
> - ports-implemented = <0x1>;
> + sata_aux_bus {
> + #address-cells = <1>;
> + #size-cells = <2>;
> + compatible = "simple-bus";
> + ranges = <0x0 0x4a140000 0x0 0x1200>;
> + dma-ranges = <0x0 0x0 0x1 0x00000000>;
> + sata: sata@4a141100 {
> + compatible = "snps,dwc-ahci";
> + reg = <0x0 0x0 0x1100>, <0x1100 0x0 0x7>;
> + interrupts = <GIC_SPI 49 IRQ_TYPE_LEVEL_HIGH>;
> + phys = <&sata_phy>;
> + phy-names = "sata-phy";
> + clocks = <&l3init_clkctrl DRA7_L3INIT_SATA_CLKCTRL 8>;
> + ti,hwmods = "sata";
> + ports-implemented = <0x1>;
> + };
> };
>
> /* OCP2SCP1 */
> --
> Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
> Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
>