[PATCH v2 4/4] iommu: dart: Support t6000 variant

Janne Grunau j at jannau.net
Mon May 2 23:23:01 PDT 2022


From: Sven Peter <sven at svenpeter.dev>

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

Signed-off-by: Sven Peter <sven at svenpeter.dev>
Co-developed-by: Janne Grunau <j at jannau.net>
Signed-off-by: Janne Grunau <j at jannau.net>

---
Changes since v1:
 - use APPLE_DART PTE format for dart-t6000
---
 drivers/iommu/apple-dart.c | 24 +++++++++++++++++++++---
 1 file changed, 21 insertions(+), 3 deletions(-)

diff --git a/drivers/iommu/apple-dart.c b/drivers/iommu/apple-dart.c
index decafb07ad08..fe0dedd67fd8 100644
--- a/drivers/iommu/apple-dart.c
+++ b/drivers/iommu/apple-dart.c
@@ -81,10 +81,16 @@
 #define DART_TTBR_VALID BIT(31)
 #define DART_TTBR_SHIFT 12
 
+struct apple_dart_hw {
+	u32 oas;
+	enum io_pgtable_fmt fmt;
+};
+
 /*
  * 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 +104,7 @@
  */
 struct apple_dart {
 	struct device *dev;
+	const struct apple_dart_hw *hw;
 
 	void __iomem *regs;
 
@@ -421,13 +428,13 @@ 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,
 	};
 
 	dart_domain->pgtbl_ops =
-		alloc_io_pgtable_ops(APPLE_DART, &pgtbl_cfg, domain);
+		alloc_io_pgtable_ops(dart->hw->fmt, &pgtbl_cfg, domain);
 	if (!dart_domain->pgtbl_ops) {
 		ret = -ENOMEM;
 		goto done;
@@ -857,6 +864,7 @@ 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);
@@ -946,8 +954,18 @@ static int apple_dart_remove(struct platform_device *pdev)
 	return 0;
 }
 
+static const struct apple_dart_hw apple_dart_hw_t8103 = {
+	.oas = 36,
+	.fmt = APPLE_DART,
+};
+static const struct apple_dart_hw apple_dart_hw_t6000 = {
+	.oas = 42,
+	.fmt = APPLE_DART2,
+};
+
 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);
-- 
2.35.1




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