[PATCH 4/4] iommu: dart: Support t6000 variant

Sven Peter sven at svenpeter.dev
Wed Nov 17 13:15:09 PST 2021


The M1 Pro/Max SoCs come with a new variant of DART which supports a
larger physical address space with a slightly different PTE format.
Pass through the correct paddr address space size to the io-pgtable code
which will take care of the rest.

Signed-off-by: Sven Peter <sven at svenpeter.dev>
---
 drivers/iommu/apple-dart.c | 19 +++++++++++++++++--
 1 file changed, 17 insertions(+), 2 deletions(-)

diff --git a/drivers/iommu/apple-dart.c b/drivers/iommu/apple-dart.c
index 565ef5598811..c04648dfd747 100644
--- a/drivers/iommu/apple-dart.c
+++ b/drivers/iommu/apple-dart.c
@@ -81,10 +81,15 @@
 #define DART_TTBR_VALID BIT(31)
 #define DART_TTBR_SHIFT 12
 
+struct apple_dart_hw {
+	u32 oas;
+};
+
 /*
  * Private structure associated with each DART device.
  *
  * @dev: device struct
+ * @hw: SoC-specific hardware data
  * @regs: mapped MMIO region
  * @irq: interrupt number, can be shared with other DARTs
  * @clks: clocks associated with this DART
@@ -98,6 +103,7 @@
  */
 struct apple_dart {
 	struct device *dev;
+	const struct apple_dart_hw *hw;
 
 	void __iomem *regs;
 
@@ -421,7 +427,7 @@ static int apple_dart_finalize_domain(struct iommu_domain *domain,
 	pgtbl_cfg = (struct io_pgtable_cfg){
 		.pgsize_bitmap = dart->pgsize,
 		.ias = 32,
-		.oas = 36,
+		.oas = dart->hw->oas,
 		.coherent_walk = 1,
 		.iommu_dev = dart->dev,
 	};
@@ -855,6 +861,7 @@ static int apple_dart_probe(struct platform_device *pdev)
 		return -ENOMEM;
 
 	dart->dev = dev;
+	dart->hw = of_device_get_match_data(dev);
 	spin_lock_init(&dart->lock);
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -944,8 +951,16 @@ static int apple_dart_remove(struct platform_device *pdev)
 	return 0;
 }
 
+static const struct apple_dart_hw apple_dart_hw_t8103 = {
+	.oas = 36,
+};
+static const struct apple_dart_hw apple_dart_hw_t6000 = {
+	.oas = 42,
+};
+
 static const struct of_device_id apple_dart_of_match[] = {
-	{ .compatible = "apple,t8103-dart", .data = NULL },
+	{ .compatible = "apple,t8103-dart", .data = &apple_dart_hw_t8103 },
+	{ .compatible = "apple,t6000-dart", .data = &apple_dart_hw_t6000 },
 	{},
 };
 MODULE_DEVICE_TABLE(of, apple_dart_of_match);
-- 
2.25.1




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