[PATCH v2 5/8] x86/MCE/AMD: Use macros to get bitfields in translation code

[Yazen Ghannam]

From: Yazen Ghannam <yazen.ghannam@xxxxxxx>

Define macros to get individual bits and bitfields. Use these to make
the code more readable.

Signed-off-by: Yazen Ghannam <yazen.ghannam@xxxxxxx>
---
Link:
https://lkml.kernel.org/r/20200814191449.183998-3-Yazen.Ghannam@xxxxxxx

v1 -> v2:
* New patch based on comments for v1 Patch 2.

 arch/x86/kernel/cpu/mce/amd.c | 46 +++++++++++++++++------------------
 1 file changed, 23 insertions(+), 23 deletions(-)

diff --git a/arch/x86/kernel/cpu/mce/amd.c b/arch/x86/kernel/cpu/mce/amd.c
index 1e0510fd5afc..90c3ad61ae19 100644
--- a/arch/x86/kernel/cpu/mce/amd.c
+++ b/arch/x86/kernel/cpu/mce/amd.c
@@ -675,6 +675,9 @@ void mce_amd_feature_init(struct cpuinfo_x86 *c)
 		deferred_error_interrupt_enable(c);
 }
 
+#define get_bits(x, msb, lsb)	((x & GENMASK_ULL(msb, lsb)) >> lsb)
+#define get_bit(x, bit)		((x >> bit) & BIT(0))
+
 #define DF_F0_FABRICINSTINFO3	0x50
 #define DF_F0_MMIOHOLE		0x104
 #define DF_F0_DRAMBASEADDR	0x110
@@ -704,7 +707,7 @@ int umc_normaddr_to_sysaddr(u64 norm_addr, u16 nid, u8 umc, u64 *sys_addr)
 
 	/* Remove HiAddrOffset from normalized address, if enabled: */
 	if (tmp & BIT(0)) {
-		u64 hi_addr_offset = (tmp & GENMASK_ULL(31, 20)) << 8;
+		u64 hi_addr_offset = get_bits(tmp, 31, 20) << 28;
 
 		/* Check if base 1 is used. */
 		if (norm_addr >= hi_addr_offset) {
@@ -723,10 +726,10 @@ int umc_normaddr_to_sysaddr(u64 norm_addr, u16 nid, u8 umc, u64 *sys_addr)
 		goto out_err;
 	}
 
-	lgcy_mmio_hole_en = tmp & BIT(1);
-	intlv_num_chan	  = (tmp >> 4) & 0xF;
-	intlv_addr_sel	  = (tmp >> 8) & 0x7;
-	dram_base_addr	  = (tmp & GENMASK_ULL(31, 12)) << 16;
+	lgcy_mmio_hole_en = get_bit(tmp, 1);
+	intlv_num_chan	  = get_bits(tmp, 7, 4);
+	intlv_addr_sel	  = get_bits(tmp, 10, 8);
+	dram_base_addr	  = get_bits(tmp, 31, 12) << 28;
 
 	/* {0, 1, 2, 3} map to address bits {8, 9, 10, 11} respectively */
 	if (intlv_addr_sel > 3) {
@@ -738,9 +741,9 @@ int umc_normaddr_to_sysaddr(u64 norm_addr, u16 nid, u8 umc, u64 *sys_addr)
 	if (amd_df_indirect_read(nid, 0, DF_F0_DRAMLIMITADDR + (8 * base), umc, &tmp))
 		goto out_err;
 
-	intlv_num_sockets = (tmp >> 8) & 0x1;
-	intlv_num_dies	  = (tmp >> 10) & 0x3;
-	dram_limit_addr	  = ((tmp & GENMASK_ULL(31, 12)) << 16) | GENMASK_ULL(27, 0);
+	intlv_num_sockets = get_bit(tmp, 8);
+	intlv_num_dies	  = get_bits(tmp, 11, 10);
+	dram_limit_addr	  = (get_bits(tmp, 31, 12) << 28) | GENMASK_ULL(27, 0);
 
 	intlv_addr_bit = intlv_addr_sel + 8;
 
@@ -793,7 +796,7 @@ int umc_normaddr_to_sysaddr(u64 norm_addr, u16 nid, u8 umc, u64 *sys_addr)
 		if (amd_df_indirect_read(nid, 0, DF_F0_FABRICINSTINFO3, umc, &tmp))
 			goto out_err;
 
-		cs_fabric_id = (tmp >> 8) & 0xFF;
+		cs_fabric_id = get_bits(tmp, 15, 8);
 		die_id_bit   = 0;
 
 		/* If interleaved over more than 1 channel: */
@@ -812,16 +815,16 @@ int umc_normaddr_to_sysaddr(u64 norm_addr, u16 nid, u8 umc, u64 *sys_addr)
 		/* If interleaved over more than 1 die. */
 		if (intlv_num_dies) {
 			sock_id_bit  = die_id_bit + intlv_num_dies;
-			die_id_shift = (tmp >> 24) & 0xF;
-			die_id_mask  = (tmp >> 8) & 0xFF;
+			die_id_shift = get_bits(tmp, 27, 24);
+			die_id_mask  = get_bits(tmp, 15, 8);
 
 			cs_id |= ((cs_fabric_id & die_id_mask) >> die_id_shift) << die_id_bit;
 		}
 
 		/* If interleaved over more than 1 socket. */
 		if (intlv_num_sockets) {
-			socket_id_shift	= (tmp >> 28) & 0xF;
-			socket_id_mask	= (tmp >> 16) & 0xFF;
+			socket_id_shift	= get_bits(tmp, 31, 28);
+			socket_id_mask	= get_bits(tmp, 23, 16);
 
 			cs_id |= ((cs_fabric_id & socket_id_mask) >> socket_id_shift) << sock_id_bit;
 		}
@@ -834,7 +837,7 @@ int umc_normaddr_to_sysaddr(u64 norm_addr, u16 nid, u8 umc, u64 *sys_addr)
 		 * bits there are. "intlv_addr_bit" tells us how many "Y" bits
 		 * there are (where "I" starts).
 		 */
-		temp_addr_y = ret_addr & GENMASK_ULL(intlv_addr_bit-1, 0);
+		temp_addr_y = get_bits(ret_addr, intlv_addr_bit-1, 0);
 		temp_addr_i = (cs_id << intlv_addr_bit);
 		temp_addr_x = (ret_addr & GENMASK_ULL(63, intlv_addr_bit)) << num_intlv_bits;
 		ret_addr    = temp_addr_x | temp_addr_i | temp_addr_y;
@@ -854,16 +857,13 @@ int umc_normaddr_to_sysaddr(u64 norm_addr, u16 nid, u8 umc, u64 *sys_addr)
 	}
 
 	if (hash_enabled) {
-		/* Save some parentheses and grab ls-bit at the end. */
-		hashed_bit =	(ret_addr >> 12) ^
-				(ret_addr >> 18) ^
-				(ret_addr >> 21) ^
-				(ret_addr >> 30) ^
-				cs_id;
-
-		hashed_bit &= BIT(0);
+		hashed_bit =	get_bit(ret_addr, 12) ^
+				get_bit(ret_addr, 18) ^
+				get_bit(ret_addr, 21) ^
+				get_bit(ret_addr, 30) ^
+				get_bit(cs_id, 0);
 
-		if (hashed_bit != ((ret_addr >> intlv_addr_bit) & BIT(0)))
+		if (hashed_bit != get_bit(ret_addr, intlv_addr_bit))
 			ret_addr ^= BIT(intlv_addr_bit);
 	}
 
-- 
2.25.1