iommu: apple-dart: Clear stream error indicator bits for T8110 DARTs

These registers exist at least on the t602x variant, and if not cleared
the IRQ will never clear.

Signed-off-by: Hector Martin <marcan@marcan.st>

Author: marcan

drivers/iommu/apple-dart.c

@@ -123,6 +123,8 @@
 #define DART_T8110_ERROR_ADDR_LO 0x170
 #define DART_T8110_ERROR_ADDR_HI 0x174
 
+#define DART_T8110_ERROR_STREAMS 0x1c0
+
 #define DART_T8110_PROTECT 0x200
 #define DART_T8110_UNPROTECT 0x204
 #define DART_T8110_PROTECT_LOCK 0x208
@@ -1231,6 +1233,7 @@ static irqreturn_t apple_dart_t8110_irq(int irq, void *dev)
 	u32 addr_hi = readl(dart->regs + DART_T8110_ERROR_ADDR_HI);
 	u64 addr = addr_lo | (((u64)addr_hi) << 32);
 	u8 stream_idx = FIELD_GET(DART_T8110_ERROR_STREAM, error);
+	int i;
 
 	if (!(error & DART_T8110_ERROR_FLAG))
 		return IRQ_NONE;
@@ -1257,6 +1260,9 @@ static irqreturn_t apple_dart_t8110_irq(int irq, void *dev)
 		error, stream_idx, error_code, fault_name, addr);
 
 	writel(error, dart->regs + DART_T8110_ERROR);
+	for (i = 0; i < BITS_TO_U32(dart->num_streams); i++)
+		writel(U32_MAX, dart->regs + DART_T8110_ERROR_STREAMS + 4 * i);
+
 	return IRQ_HANDLED;
 }