[PATCH 23/25] x86/MCE/AMD: Update CS ID calculation to match reference code

[Yazen Ghannam]

From: Yazen Ghannam <yazen.ghannam@xxxxxxx>

Redo the current CS ID calculations to match the reference code. Helper
functions are introduced that will be expanded for future DF versions.

Signed-off-by: Yazen Ghannam <yazen.ghannam@xxxxxxx>
---
 arch/x86/kernel/cpu/mce/amd.c | 50 ++++++++++++++++++++++-------------
 1 file changed, 31 insertions(+), 19 deletions(-)

diff --git a/arch/x86/kernel/cpu/mce/amd.c b/arch/x86/kernel/cpu/mce/amd.c
index 01931f98c6d9..3340f8326681 100644
--- a/arch/x86/kernel/cpu/mce/amd.c
+++ b/arch/x86/kernel/cpu/mce/amd.c
@@ -924,45 +924,57 @@ static u8 get_socket_id_shift(struct addr_ctx *ctx)
 	return (ctx->reg_fab_id_mask0 >> 28) & 0xF;
 }
 
+static u8 get_dst_fabric_id(struct addr_ctx *ctx)
+{
+	return ctx->reg_limit_addr & 0xFF;
+}
+
+static u8 get_component_id_mask(struct addr_ctx *ctx)
+{
+	return (~(ctx->socket_id_mask | ctx->die_id_mask)) & 0xFF;
+}
+
+static u8 calc_level_bits(u8 id, u8 level_mask, u8 shift, u8 mask, u8 num_bits)
+{
+	return (((id & level_mask) >> shift) & mask) << num_bits;
+}
+
 static int calculate_cs_id(struct addr_ctx *ctx)
 {
-	u8 die_id_bit, sock_id_bit, cs_mask = 0;
+	u8 mask, num_intlv_bits = ctx->intlv_num_chan;
+	u8 dst_fabric_id = get_dst_fabric_id(ctx);
 
 	if (get_cs_fabric_id(ctx))
 		return -EINVAL;
 
 	get_masks(ctx);
 
-	die_id_bit   = 0;
+	mask = get_component_id_mask(ctx);
+	ctx->cs_id = (ctx->cs_fabric_id & mask) - (dst_fabric_id & mask);
 
-	/* If interleaved over more than 1 channel: */
-	if (ctx->intlv_num_chan) {
-		die_id_bit = ctx->intlv_num_chan;
-		cs_mask	   = (1 << die_id_bit) - 1;
-		ctx->cs_id = ctx->cs_fabric_id & cs_mask;
-	}
-
-	/* Return early if no die interleaving and no socket interleaving. */
-	if (!(ctx->intlv_num_dies || ctx->intlv_num_sockets))
-		return 0;
-
-	sock_id_bit = die_id_bit;
+	mask = (1 << num_intlv_bits) - 1;
+	ctx->cs_id &= mask;
 
 	/* If interleaved over more than 1 die: */
 	if (ctx->intlv_num_dies) {
 		u8 die_id_shift = get_die_id_shift(ctx);
 
-		sock_id_bit  = die_id_bit + ctx->intlv_num_dies;
-		ctx->cs_id |= ((ctx->cs_fabric_id & ctx->die_id_mask)
-				>> die_id_shift) << die_id_bit;
+		mask = (1 << ctx->intlv_num_dies) - 1;
+
+		ctx->cs_id |= calc_level_bits(ctx->cs_fabric_id, ctx->die_id_mask,
+					      die_id_shift, mask, num_intlv_bits);
+
+		num_intlv_bits += ctx->intlv_num_dies;
 	}
 
 	/* If interleaved over more than 1 socket: */
 	if (ctx->intlv_num_sockets) {
 		u8 socket_id_shift = get_socket_id_shift(ctx);
 
-		ctx->cs_id |= ((ctx->cs_fabric_id & ctx->socket_id_mask)
-				>> socket_id_shift) << sock_id_bit;
+		mask = (1 << ctx->intlv_num_sockets) - 1;
+
+		ctx->cs_id |= calc_level_bits(ctx->cs_fabric_id, ctx->socket_id_mask,
+					      socket_id_shift, mask, num_intlv_bits);
 	}
 
 	return 0;
-- 
2.25.1