Re: [PATCHv5 1/3] ARM: mm: add support for HW coherent systems in PL310 cache

--- a/arch/arm/mm/cache-l2x0.c
+++ b/arch/arm/mm/cache-l2x0.c

@@ -1069,6 +1069,33 @@ static const struct l2c_init_data of_l2c310_data __initconst = {
 };
 
 /*
+ * This is a variant of the of_l2c310_data with .sync set to
+ * NULL. Outer sync operations are not needed when the system is I/O
+ * coherent, and potentially harmful in certain situations (PCIe/PL310
+ * deadlock on Armada 375/38x due to hardware I/O coherency). The
+ * other operations are kept because they are infrequent (therefore do
+ * not cause the deadlock in practice) and needed for secondary CPU
+ * boot and other power management activities.
+ */
+static const struct l2c_init_data of_l2c310_coherent_data __initconst = {
+	.type = "L2C-310 Coherent",
+	.way_size_0 = SZ_8K,
+	.num_lock = 8,
+	.of_parse = l2c310_of_parse,
+	.enable = l2c310_enable,
+	.fixup = l2c310_fixup,
+	.save  = l2c310_save,
+	.outer_cache = {
+		.inv_range   = l2c210_inv_range,
+		.clean_range = l2c210_clean_range,
+		.flush_range = l2c210_flush_range,
+		.flush_all   = l2c210_flush_all,
+		.disable     = l2c310_disable,
+		.resume      = l2c310_resume,
+	},
+};
+
+/*
  * Note that the end addresses passed to Linux primitives are
  * noninclusive, while the hardware cache range operations use
  * inclusive start and end addresses.

@@ -1487,6 +1514,10 @@ int __init l2x0_of_init(u32 aux_val, u32 aux_mask)
 
 	data = of_match_node(l2x0_ids, np)->data;
 
+	if (of_device_is_compatible(np, "arm,pl310-cache") &&
+	    of_property_read_bool(np, "arm,io-coherent"))
+		data = &of_l2c310_coherent_data;