nb/intel/sandybridge: Add and use BROADCAST_CH for IOSAV

We have a single IOSAV sequence that is broadcast across all channels.
Introduce the BROADCAST_CH macro, so that we can use the per-channel
register definitions. Treating all IOSAV sequence writes the same eases
the refactoring done in subsequent commits. Also, drop the broadcast
register definitions for the IOSAV commands, as they are now obsolete.

Line length limits are not for review. Breaking the lines unnecessarily
complicates search and replace operations, and wil be taken care of in
subsequent commits.

Tested with BUILD_TIMELESS=1, ASUS P8Z77-V LX2 remains unchanged.

Change-Id: I2dbb100fcad68d128e92b1bc9321fc1e53b748c9
Signed-off-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/40976
Reviewed-by: Felix Held <felix-coreboot@felixheld.de>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
diff --git a/src/northbridge/intel/sandybridge/mchbar_regs.h b/src/northbridge/intel/sandybridge/mchbar_regs.h
index 74377b2..286b556 100644
--- a/src/northbridge/intel/sandybridge/mchbar_regs.h
+++ b/src/northbridge/intel/sandybridge/mchbar_regs.h
@@ -209,6 +209,12 @@
 
 #define CRCOMPOFST2			0x3714 /* CMD DRV, SComp and Static Leg controls */
 
+/*
+ * The register bank that would correspond to Channel 3 are actually "broadcast" registers.
+ * They can be used to write values to all channels. Use this macro instead of a literal '3'.
+ */
+#define BROADCAST_CH	3
+
 /* MC per-channel registers */
 #define TC_DBP_ch(ch)			Cx(0x4000, ch) /* Timings: BIN */
 #define TC_RAP_ch(ch)			Cx(0x4004, ch) /* Timings: Regular access */
@@ -315,12 +321,6 @@
 
 #define IOSAV_By_BW_SERROR_C(y)	Ly(0x4d40, y) /* IOSAV Bytelane Bit-wise error */
 
-#define IOSAV_n_SP_CMD_ADDR(n)	Ly(0x4e00, n) /* Sub-sequence special command address */
-#define IOSAV_n_ADDR_UPDATE(n)	Ly(0x4e10, n) /* Address update after command execution */
-#define IOSAV_n_SP_CMD_CTRL(n)	Ly(0x4e20, n) /* Command signals in sub-sequence command */
-#define IOSAV_n_SUBSEQ_CTRL(n)	Ly(0x4e30, n) /* Sub-sequence command parameter control */
-#define IOSAV_n_ADDRESS_LFSR(n)	Ly(0x4e40, n) /* 23-bit LFSR value of the sequence */
-
 #define PM_THML_STAT		0x4e80 /* Thermal status of each rank */
 #define IOSAV_SEQ_CTL		0x4e84 /* IOSAV sequence level control */
 #define IOSAV_DATA_CTL		0x4e88 /* Data control in IOSAV mode */