Re: [PATCH 4/4] iommu: dart: Add support for M1 USB4 PCIe DART

Hector Martin
2023-01-28T11:46:51Z

On 28/01/2023 20.11, Sven Peter wrote:
> This variant of the regular t8103 DART is used for the two
> USB4/Thunderbolt PCIe controllers. It supports 64 instead of 16 streams
> which requires a slightly different MMIO layout. We also disallow bypass
> support since these DARTs will only ever be used for externally facing
> devices on the USB4 ports.
>
> Signed-off-by: Sven Peter <sven@svenpeter.dev>
> ---
> drivers/iommu/apple-dart.c | 31 +++++++++++++++++++++++++++++++
> 1 file changed, 31 insertions(+)
>
> diff --git a/drivers/iommu/apple-dart.c b/drivers/iommu/apple-dart.c
> index 7579c97a9062..a1304ba3639b 100644
> --- a/drivers/iommu/apple-dart.c
> +++ b/drivers/iommu/apple-dart.c
> @@ -81,6 +81,7 @@
> #define DART_T8020_TCR_BYPASS_DAPF BIT(12)
>
> #define DART_T8020_TTBR 0x200
> +#define DART_T8020_USB4_TTBR 0x400
> #define DART_T8020_TTBR_VALID BIT(31)
> #define DART_T8020_TTBR_ADDR_FIELD_SHIFT 0
> #define DART_T8020_TTBR_SHIFT 12
> @@ -1184,6 +1185,35 @@ static const struct apple_dart_hw apple_dart_hw_t8103 = {
> .ttbr_shift = DART_T8020_TTBR_SHIFT,
> .ttbr_count = 4,
> };
> +
> +static const struct apple_dart_hw apple_dart_hw_t8103_usb4 = {
> + .type = DART_T8020,
> + .irq_handler = apple_dart_t8020_irq,
> + .invalidate_tlb = apple_dart_t8020_hw_invalidate_tlb,
> + .oas = 36,
> + .fmt = APPLE_DART,
> + .max_sid_count = 64,
> +
> + .enable_streams = DART_T8020_STREAMS_ENABLE,
> + .lock = DART_T8020_CONFIG,
> + .lock_bit = DART_T8020_CONFIG_LOCK,
> +
> + .error = DART_T8020_ERROR,
> +
> + .tcr = DART_T8020_TCR,
> + .tcr_enabled = DART_T8020_TCR_TRANSLATE_ENABLE,
> + .tcr_disabled = 0,
> + .tcr_bypass = 0,
> +
> + .ttbr = DART_T8020_USB4_TTBR,
> + .ttbr_valid = DART_T8020_TTBR_VALID,
> + .ttbr_addr_field_shift = DART_T8020_TTBR_ADDR_FIELD_SHIFT,
> + .ttbr_shift = DART_T8020_TTBR_SHIFT,
> + .ttbr_count = 4,
> +
> + .disable_bypass = true,
> +};
> +
> static const struct apple_dart_hw apple_dart_hw_t6000 = {
> .type = DART_T6000,
> .irq_handler = apple_dart_t8020_irq,
> @@ -1276,6 +1306,7 @@ DEFINE_SIMPLE_DEV_PM_OPS(apple_dart_pm_ops, apple_dart_suspend, apple_dart_resum
>
> static const struct of_device_id apple_dart_of_match[] = {
> { .compatible = "apple,t8103-dart", .data = &apple_dart_hw_t8103 },
> + { .compatible = "apple,t8103-dart-usb4", .data = &apple_dart_hw_t8103_usb4 },
> { .compatible = "apple,t8110-dart", .data = &apple_dart_hw_t8110 },
> { .compatible = "apple,t6000-dart", .data = &apple_dart_hw_t6000 },
> {},

Other than the compatible as per patch #1,

Acked-by: Hector Martin <marcan@marcan.st>

- Hector