[PATCH 18/25] x86/MCE/AMD: Define function to make space for CS ID

[Yazen Ghannam]

From: Yazen Ghannam <yazen.ghannam@xxxxxxx>

Move code to makes a gap for the CS ID into a separate helper function.
The exact bits to use vary based on interleaving mode. New interleaving
modes in future DF versions will be added as new cases.

Also, introduce a helper function that does the bit manipulation to make
the gap.

Signed-off-by: Yazen Ghannam <yazen.ghannam@xxxxxxx>
---
 arch/x86/kernel/cpu/mce/amd.c | 43 ++++++++++++++++++++++++++++-------
 1 file changed, 35 insertions(+), 8 deletions(-)

diff --git a/arch/x86/kernel/cpu/mce/amd.c b/arch/x86/kernel/cpu/mce/amd.c
index 8f4838a3d509..ba365901e39d 100644
--- a/arch/x86/kernel/cpu/mce/amd.c
+++ b/arch/x86/kernel/cpu/mce/amd.c
@@ -860,6 +860,38 @@ static void get_intlv_num_sockets(struct addr_ctx *ctx)
 	ctx->intlv_num_sockets = (ctx->reg_limit_addr >> 8) & 0x1;
 }
 
+static void expand_bits(u8 start_bit, u8 num_bits, u64 *value)
+{
+	u64 temp1, temp2;
+
+	if (start_bit == 0) {
+		*value <<= num_bits;
+		return;
+	}
+
+	temp1 = *value & GENMASK_ULL(start_bit - 1, 0);
+	temp2 = (*value & GENMASK_ULL(63, start_bit)) << num_bits;
+	*value = temp1 | temp2;
+}
+
+static void make_space_for_cs_id(struct addr_ctx *ctx)
+{
+	u8 num_intlv_bits;
+
+	switch (ctx->intlv_mode) {
+	case NOHASH_2CH:
+	case DF2_HASH_2CH:
+		num_intlv_bits = ctx->intlv_num_chan;
+		num_intlv_bits += ctx->intlv_num_dies;
+		num_intlv_bits += ctx->intlv_num_sockets;
+		expand_bits(ctx->intlv_addr_bit, num_intlv_bits, &ctx->ret_addr);
+		break;
+	default:
+		/* Valid interleaving modes where checked earlier. */
+		break;
+	}
+}
+
 static int denormalize_addr(struct addr_ctx *ctx)
 {
 	u32 tmp;
@@ -878,13 +910,11 @@ static int denormalize_addr(struct addr_ctx *ctx)
 	get_intlv_num_dies(ctx);
 	get_intlv_num_sockets(ctx);
 
-	num_intlv_bits = ctx->intlv_num_chan;
-	num_intlv_bits += ctx->intlv_num_dies;
-	num_intlv_bits += ctx->intlv_num_sockets;
+	make_space_for_cs_id(ctx);
 
 	if (num_intlv_bits > 0) {
-		u64 temp_addr_x, temp_addr_i, temp_addr_y;
 		u8 die_id_bit, sock_id_bit, cs_fabric_id;
+		u64 temp_addr_i;
 
 		/*
 		 * Read FabricBlockInstanceInformation3_CS[BlockFabricID].
@@ -939,11 +969,8 @@ static int denormalize_addr(struct addr_ctx *ctx)
 		 * bits there are. "intlv_addr_bit" tells us how many "Y" bits
 		 * there are (where "I" starts).
 		 */
-		temp_addr_y = ctx->ret_addr & GENMASK_ULL(ctx->intlv_addr_bit - 1, 0);
 		temp_addr_i = (ctx->cs_id << ctx->intlv_addr_bit);
-		temp_addr_x = (ctx->ret_addr & GENMASK_ULL(63, ctx->intlv_addr_bit))
-			       << num_intlv_bits;
-		ctx->ret_addr    = temp_addr_x | temp_addr_i | temp_addr_y;
+		ctx->ret_addr |= temp_addr_i;
 	}
 
 	return 0;
-- 
2.25.1