Re: [PATCH 4/7] iommu: dart: Support a variable number of TTBRs per stream

From: Sven Peter
Date: Wed Jan 04 2023 - 08:19:40 EST


On Wed, Jan 4, 2023, at 12:00, Hector Martin wrote:
> T8110 only has one TTBR per stream, so un-hardcode that.
>
> Signed-off-by: Hector Martin <marcan@xxxxxxxxx>
> ---
> drivers/iommu/apple-dart.c | 26 ++++++++++++++++++--------
> 1 file changed, 18 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/iommu/apple-dart.c b/drivers/iommu/apple-dart.c
> index 48743bcd5b9d..189487c1d978 100644
> --- a/drivers/iommu/apple-dart.c
> +++ b/drivers/iommu/apple-dart.c
> @@ -77,15 +77,21 @@
> #define DART_TCR_BYPASS0_ENABLE BIT(8)
> #define DART_TCR_BYPASS1_ENABLE BIT(12)
>
> -#define DART_TTBR(sid, idx) (0x200 + 16 * (sid) + 4 * (idx))
> #define DART_TTBR_VALID BIT(31)
> #define DART_TTBR_SHIFT 12
>
> +#define DART_TTBR(dart, sid, idx) (0x200 + \
> + (((dart)->hw->ttbr_count * (sid)) << 2) + \
> + ((idx) << 2))
> +
> +
> struct apple_dart_hw {
> u32 oas;
> enum io_pgtable_fmt fmt;
>
> int max_sid_count;
> +
> + int ttbr_count;
> };
>
> /*
> @@ -245,7 +251,7 @@ static void apple_dart_hw_set_ttbr(struct
> apple_dart_stream_map *stream_map,
> WARN_ON(paddr & ((1 << DART_TTBR_SHIFT) - 1));
> for_each_set_bit(sid, stream_map->sidmap, dart->num_streams)
> writel(DART_TTBR_VALID | (paddr >> DART_TTBR_SHIFT),
> - dart->regs + DART_TTBR(sid, idx));
> + dart->regs + DART_TTBR(dart, sid, idx));
> }
>
> static void apple_dart_hw_clear_ttbr(struct apple_dart_stream_map
> *stream_map,
> @@ -255,7 +261,7 @@ static void apple_dart_hw_clear_ttbr(struct
> apple_dart_stream_map *stream_map,
> int sid;
>
> for_each_set_bit(sid, stream_map->sidmap, dart->num_streams)
> - writel(0, dart->regs + DART_TTBR(sid, idx));
> + writel(0, dart->regs + DART_TTBR(dart, sid, idx));
> }
>
> static void
> @@ -263,7 +269,7 @@ apple_dart_hw_clear_all_ttbrs(struct
> apple_dart_stream_map *stream_map)
> {
> int i;
>
> - for (i = 0; i < DART_MAX_TTBR; ++i)
> + for (i = 0; i < stream_map->dart->hw->ttbr_count; ++i)
> apple_dart_hw_clear_ttbr(stream_map, i);
> }
>
> @@ -415,7 +421,7 @@ apple_dart_setup_translation(struct
> apple_dart_domain *domain,
> for (i = 0; i < pgtbl_cfg->apple_dart_cfg.n_ttbrs; ++i)
> apple_dart_hw_set_ttbr(stream_map, i,
> pgtbl_cfg->apple_dart_cfg.ttbr[i]);
> - for (; i < DART_MAX_TTBR; ++i)
> + for (; i < stream_map->dart->hw->ttbr_count; ++i)
> apple_dart_hw_clear_ttbr(stream_map, i);
>
> apple_dart_hw_enable_translation(stream_map);
> @@ -956,11 +962,15 @@ static const struct apple_dart_hw apple_dart_hw_t8103 = {
> .oas = 36,
> .fmt = APPLE_DART,
> .max_sid_count = 16,
> +
> + .ttbr_count = 4,
> };
> static const struct apple_dart_hw apple_dart_hw_t6000 = {
> .oas = 42,
> .fmt = APPLE_DART2,
> .max_sid_count = 16,
> +
> + .ttbr_count = 4,
> };
>
> static __maybe_unused int apple_dart_suspend(struct device *dev)
> @@ -970,9 +980,9 @@ static __maybe_unused int apple_dart_suspend(struct
> device *dev)
>
> for (sid = 0; sid < dart->num_streams; sid++) {
> dart->save_tcr[sid] = readl_relaxed(dart->regs + DART_TCR(sid));
> - for (idx = 0; idx < DART_MAX_TTBR; idx++)
> + for (idx = 0; idx < dart->hw->ttbr_count; idx++)
> dart->save_ttbr[sid][idx] =
> - readl(dart->regs + DART_TTBR(sid, idx));
> + readl(dart->regs + DART_TTBR(dart, sid, idx));
> }
>
> return 0;
> @@ -993,7 +1003,7 @@ static __maybe_unused int apple_dart_resume(struct
> device *dev)
> for (sid = 0; sid < dart->num_streams; sid++) {
> for (idx = 0; idx < DART_MAX_TTBR; idx++)

s/DART_MAX_TTBR/dart->hw->ttbr_count/ I think.

With that fixed:

Reviewed-by: Sven Peter <sven@xxxxxxxxxxxxx>



Sven