diff --git a/drivers/edac/amd64_edac.c b/drivers/edac/amd64_edac.c
index 62b4ae9eb337..306850879f20 100644
--- a/drivers/edac/amd64_edac.c
+++ b/drivers/edac/amd64_edac.c
@@ -265,37 +265,6 @@ static int amd64_get_scrub_rate(struct mem_ctl_info *mci)
 	return retval;
 }
 
-/* Map from a CSROW entry to the mask entry that operates on it */
-static inline u32 amd64_map_to_dcs_mask(struct amd64_pvt *pvt, int csrow)
-{
-	if (boot_cpu_data.x86 == 0xf && pvt->ext_model < K8_REV_F)
-		return csrow;
-	else
-		return csrow >> 1;
-}
-
-/* return the 'base' address the i'th CS entry of the 'dct' DRAM controller */
-static u32 amd64_get_dct_base(struct amd64_pvt *pvt, int dct, int csrow)
-{
-	if (dct == 0)
-		return pvt->dcsb0[csrow];
-	else
-		return pvt->dcsb1[csrow];
-}
-
-/*
- * Return the 'mask' address the i'th CS entry. This function is needed because
- * there number of DCSM registers on Rev E and prior vs Rev F and later is
- * different.
- */
-static u32 amd64_get_dct_mask(struct amd64_pvt *pvt, int dct, int csrow)
-{
-	if (dct == 0)
-		return pvt->dcsm0[amd64_map_to_dcs_mask(pvt, csrow)];
-	else
-		return pvt->dcsm1[amd64_map_to_dcs_mask(pvt, csrow)];
-}
-
 /*
  * returns true if the SysAddr given by sys_addr matches the
  * DRAM base/limit associated with node_id
@@ -386,36 +355,46 @@ err_no_match:
 }
 
 /*
- * Extract the DRAM CS base address from selected csrow register.
+ * compute the CS base address of the @csrow on the DRAM controller @dct.
+ * For details see F2x[5C:40] in the processor's BKDG
  */
-static u64 base_from_dct_base(struct amd64_pvt *pvt, int csrow)
+static void get_cs_base_and_mask(struct amd64_pvt *pvt, int csrow, u8 dct,
+				 u64 *base, u64 *mask)
 {
-	return ((u64) (amd64_get_dct_base(pvt, 0, csrow) & pvt->dcsb_base)) <<
-				pvt->dcs_shift;
+	u64 csbase, csmask, base_bits, mask_bits;
+	u8 addr_shift;
+
+	if (boot_cpu_data.x86 == 0xf && pvt->ext_model < K8_REV_F) {
+		csbase		= pvt->csels[dct].csbases[csrow];
+		csmask		= pvt->csels[dct].csmasks[csrow];
+		base_bits	= GENMASK(21, 31) | GENMASK(9, 15);
+		mask_bits	= GENMASK(21, 29) | GENMASK(9, 15);
+		addr_shift	= 4;
+	} else {
+		csbase		= pvt->csels[dct].csbases[csrow];
+		csmask		= pvt->csels[dct].csmasks[csrow >> 1];
+		addr_shift	= 8;
+
+		if (boot_cpu_data.x86 == 0x15)
+			base_bits = mask_bits = GENMASK(19,30) | GENMASK(5,13);
+		else
+			base_bits = mask_bits = GENMASK(19,28) | GENMASK(5,13);
+	}
+
+	*base  = (csbase & base_bits) << addr_shift;
+
+	*mask  = ~0ULL;
+	/* poke holes for the csmask */
+	*mask &= ~(mask_bits << addr_shift);
+	/* OR them in */
+	*mask |= (csmask & mask_bits) << addr_shift;
 }
 
-/*
- * Extract the mask from the dcsb0[csrow] entry in a CPU revision-specific way.
- */
-static u64 mask_from_dct_mask(struct amd64_pvt *pvt, int csrow)
-{
-	u64 dcsm_bits, other_bits;
-	u64 mask;
+#define for_each_chip_select(i, dct, pvt) \
+	for (i = 0; i < pvt->csels[dct].b_cnt; i++)
 
-	/* Extract bits from DRAM CS Mask. */
-	dcsm_bits = amd64_get_dct_mask(pvt, 0, csrow) & pvt->dcsm_mask;
-
-	other_bits = pvt->dcsm_mask;
-	other_bits = ~(other_bits << pvt->dcs_shift);
-
-	/*
-	 * The extracted bits from DCSM belong in the spaces represented by
-	 * the cleared bits in other_bits.
-	 */
-	mask = (dcsm_bits << pvt->dcs_shift) | other_bits;
-
-	return mask;
-}
+#define for_each_chip_select_mask(i, dct, pvt) \
+	for (i = 0; i < pvt->csels[dct].m_cnt; i++)
 
 /*
  * @input_addr is an InputAddr associated with the node given by mci. Return the
@@ -429,19 +408,13 @@ static int input_addr_to_csrow(struct mem_ctl_info *mci, u64 input_addr)
 
 	pvt = mci->pvt_info;
 
-	/*
-	 * Here we use the DRAM CS Base and DRAM CS Mask registers. For each CS
-	 * base/mask register pair, test the condition shown near the start of
-	 * section 3.5.4 (p. 84, BKDG #26094, K8, revA-E).
-	 */
-	for (csrow = 0; csrow < pvt->cs_count; csrow++) {
-
-		/* This DRAM chip select is disabled on this node */
-		if ((pvt->dcsb0[csrow] & K8_DCSB_CS_ENABLE) == 0)
+	for_each_chip_select(csrow, 0, pvt) {
+		if (!csrow_enabled(csrow, 0, pvt))
 			continue;
 
-		base = base_from_dct_base(pvt, csrow);
-		mask = ~mask_from_dct_mask(pvt, csrow);
+		get_cs_base_and_mask(pvt, csrow, 0, &base, &mask);
+
+		mask = ~mask;
 
 		if ((input_addr & mask) == (base & mask)) {
 			debugf2("InputAddr 0x%lx matches csrow %d (node %d)\n",
@@ -451,7 +424,6 @@ static int input_addr_to_csrow(struct mem_ctl_info *mci, u64 input_addr)
 			return csrow;
 		}
 	}
-
 	debugf2("no matching csrow for InputAddr 0x%lx (MC node %d)\n",
 		(unsigned long)input_addr, pvt->mc_node_id);
 
@@ -779,13 +751,12 @@ static void find_csrow_limits(struct mem_ctl_info *mci, int csrow,
 	u64 base, mask;
 
 	pvt = mci->pvt_info;
-	BUG_ON((csrow < 0) || (csrow >= pvt->cs_count));
+	BUG_ON((csrow < 0) || (csrow >= pvt->csels[0].b_cnt));
 
-	base = base_from_dct_base(pvt, csrow);
-	mask = mask_from_dct_mask(pvt, csrow);
+	get_cs_base_and_mask(pvt, csrow, 0, &base, &mask);
 
 	*input_addr_min = base & ~mask;
-	*input_addr_max = base | mask | pvt->dcs_mask_notused;
+	*input_addr_max = base | mask;
 }
 
 /* Map the Error address to a PAGE and PAGE OFFSET. */
@@ -913,93 +884,62 @@ static void amd64_read_dbam_reg(struct amd64_pvt *pvt)
 }
 
 /*
- * NOTE: CPU Revision Dependent code: Rev E and Rev F
- *
- * Set the DCSB and DCSM mask values depending on the CPU revision value. Also
- * set the shift factor for the DCSB and DCSM values.
- *
- * ->dcs_mask_notused, RevE:
- *
- * To find the max InputAddr for the csrow, start with the base address and set
- * all bits that are "don't care" bits in the test at the start of section
- * 3.5.4 (p. 84).
- *
- * The "don't care" bits are all set bits in the mask and all bits in the gaps
- * between bit ranges [35:25] and [19:13]. The value REV_E_DCS_NOTUSED_BITS
- * represents bits [24:20] and [12:0], which are all bits in the above-mentioned
- * gaps.
- *
- * ->dcs_mask_notused, RevF and later:
- *
- * To find the max InputAddr for the csrow, start with the base address and set
- * all bits that are "don't care" bits in the test at the start of NPT section
- * 4.5.4 (p. 87).
- *
- * The "don't care" bits are all set bits in the mask and all bits in the gaps
- * between bit ranges [36:27] and [21:13].
- *
- * The value REV_F_F1Xh_DCS_NOTUSED_BITS represents bits [26:22] and [12:0],
- * which are all bits in the above-mentioned gaps.
+ * see BKDG, F2x[1,0][5C:40], F2[1,0][6C:60]
  */
-static void amd64_set_dct_base_and_mask(struct amd64_pvt *pvt)
+static void prep_chip_selects(struct amd64_pvt *pvt)
 {
-
 	if (boot_cpu_data.x86 == 0xf && pvt->ext_model < K8_REV_F) {
-		pvt->dcsb_base		= REV_E_DCSB_BASE_BITS;
-		pvt->dcsm_mask		= REV_E_DCSM_MASK_BITS;
-		pvt->dcs_mask_notused	= REV_E_DCS_NOTUSED_BITS;
-		pvt->dcs_shift		= REV_E_DCS_SHIFT;
-		pvt->cs_count		= 8;
-		pvt->num_dcsm		= 8;
+		pvt->csels[0].b_cnt = pvt->csels[1].b_cnt = 8;
+		pvt->csels[0].m_cnt = pvt->csels[1].m_cnt = 8;
 	} else {
-		pvt->dcsb_base		= REV_F_F1Xh_DCSB_BASE_BITS;
-		pvt->dcsm_mask		= REV_F_F1Xh_DCSM_MASK_BITS;
-		pvt->dcs_mask_notused	= REV_F_F1Xh_DCS_NOTUSED_BITS;
-		pvt->dcs_shift		= REV_F_F1Xh_DCS_SHIFT;
-		pvt->cs_count		= 8;
-		pvt->num_dcsm		= 4;
+		pvt->csels[0].b_cnt = pvt->csels[1].b_cnt = 8;
+		pvt->csels[0].m_cnt = pvt->csels[1].m_cnt = 4;
 	}
 }
 
 /*
- * Function 2 Offset F10_DCSB0; read in the DCS Base and DCS Mask hw registers
+ * Function 2 Offset F10_DCSB0; read in the DCS Base and DCS Mask registers
  */
 static void read_dct_base_mask(struct amd64_pvt *pvt)
 {
-	int cs, reg;
+	int cs;
 
-	amd64_set_dct_base_and_mask(pvt);
+	prep_chip_selects(pvt);
 
-	for (cs = 0; cs < pvt->cs_count; cs++) {
-		reg = K8_DCSB0 + (cs * 4);
+	for_each_chip_select(cs, 0, pvt) {
+		u32 reg0   = DCSB0 + (cs * 4);
+		u32 reg1   = DCSB1 + (cs * 4);
+		u32 *base0 = &pvt->csels[0].csbases[cs];
+		u32 *base1 = &pvt->csels[1].csbases[cs];
 
-		if (!amd64_read_dct_pci_cfg(pvt, reg, &pvt->dcsb0[cs]))
+		if (!amd64_read_dct_pci_cfg(pvt, reg0, base0))
 			debugf0("  DCSB0[%d]=0x%08x reg: F2x%x\n",
-				cs, pvt->dcsb0[cs], reg);
+				cs, *base0, reg0);
 
-		if (!dct_ganging_enabled(pvt)) {
-			reg = F10_DCSB1 + (cs * 4);
+		if (boot_cpu_data.x86 == 0xf || dct_ganging_enabled(pvt))
+			continue;
 
-			if (!amd64_read_dct_pci_cfg(pvt, reg, &pvt->dcsb1[cs]))
-				debugf0("  DCSB1[%d]=0x%08x reg: F2x%x\n",
-					cs, pvt->dcsb1[cs], reg);
-		}
+		if (!amd64_read_dct_pci_cfg(pvt, reg1, base1))
+			debugf0("  DCSB1[%d]=0x%08x reg: F2x%x\n",
+				cs, *base1, reg1);
 	}
 
-	for (cs = 0; cs < pvt->num_dcsm; cs++) {
-		reg = K8_DCSM0 + (cs * 4);
+	for_each_chip_select_mask(cs, 0, pvt) {
+		u32 reg0   = DCSM0 + (cs * 4);
+		u32 reg1   = DCSM1 + (cs * 4);
+		u32 *mask0 = &pvt->csels[0].csmasks[cs];
+		u32 *mask1 = &pvt->csels[1].csmasks[cs];
 
-		if (!amd64_read_dct_pci_cfg(pvt, reg, &pvt->dcsm0[cs]))
+		if (!amd64_read_dct_pci_cfg(pvt, reg0, mask0))
 			debugf0("    DCSM0[%d]=0x%08x reg: F2x%x\n",
-				cs, pvt->dcsm0[cs], reg);
+				cs, *mask0, reg0);
 
-		if (!dct_ganging_enabled(pvt)) {
-			reg = F10_DCSM1 + (cs * 4);
+		if (boot_cpu_data.x86 == 0xf || dct_ganging_enabled(pvt))
+			continue;
 
-			if (!amd64_read_dct_pci_cfg(pvt, reg, &pvt->dcsm1[cs]))
-				debugf0("    DCSM1[%d]=0x%08x reg: F2x%x\n",
-					cs, pvt->dcsm1[cs], reg);
-		}
+		if (!amd64_read_dct_pci_cfg(pvt, reg1, mask1))
+			debugf0("    DCSM1[%d]=0x%08x reg: F2x%x\n",
+				cs, *mask1, reg1);
 	}
 }
 
@@ -1261,10 +1201,11 @@ static void f10_read_dram_ctl_register(struct amd64_pvt *pvt)
  * determine channel based on the interleaving mode: F10h BKDG, 2.8.9 Memory
  * Interleaving Modes.
  */
-static u32 f10_determine_channel(struct amd64_pvt *pvt, u64 sys_addr,
+static u8 f10_determine_channel(struct amd64_pvt *pvt, u64 sys_addr,
 				int hi_range_sel, u32 intlv_en)
 {
-	u32 cs, temp, dct_sel_high = (pvt->dct_sel_low >> 1) & 1;
+	u32 temp, dct_sel_high = (pvt->dct_sel_low >> 1) & 1;
+	u8 cs;
 
 	if (dct_ganging_enabled(pvt))
 		cs = 0;
@@ -1345,14 +1286,13 @@ static inline u64 f10_get_base_addr_offset(u64 sys_addr, int hi_range_sel,
  * checks if the csrow passed in is marked as SPARED, if so returns the new
  * spare row
  */
-static inline int f10_process_possible_spare(int csrow,
-				u32 cs, struct amd64_pvt *pvt)
+static int f10_process_possible_spare(struct amd64_pvt *pvt, u8 dct, int csrow)
 {
 	u32 swap_done;
 	u32 bad_dram_cs;
 
 	/* Depending on channel, isolate respective SPARING info */
-	if (cs) {
+	if (dct) {
 		swap_done = F10_ONLINE_SPARE_SWAPDONE1(pvt->online_spare);
 		bad_dram_cs = F10_ONLINE_SPARE_BADDRAM_CS1(pvt->online_spare);
 		if (swap_done && (csrow == bad_dram_cs))
@@ -1374,11 +1314,11 @@ static inline int f10_process_possible_spare(int csrow,
  *	-EINVAL:  NOT FOUND
  *	0..csrow = Chip-Select Row
  */
-static int f10_lookup_addr_in_dct(u32 in_addr, u32 nid, u32 cs)
+static int f10_lookup_addr_in_dct(u64 in_addr, u32 nid, u8 dct)
 {
 	struct mem_ctl_info *mci;
 	struct amd64_pvt *pvt;
-	u32 cs_base, cs_mask;
+	u64 cs_base, cs_mask;
 	int cs_found = -EINVAL;
 	int csrow;
 
@@ -1388,39 +1328,25 @@ static int f10_lookup_addr_in_dct(u32 in_addr, u32 nid, u32 cs)
 
 	pvt = mci->pvt_info;
 
-	debugf1("InputAddr=0x%x  channelselect=%d\n", in_addr, cs);
+	debugf1("input addr: 0x%llx, DCT: %d\n", in_addr, dct);
 
-	for (csrow = 0; csrow < pvt->cs_count; csrow++) {
-
-		cs_base = amd64_get_dct_base(pvt, cs, csrow);
-		if (!(cs_base & K8_DCSB_CS_ENABLE))
+	for_each_chip_select(csrow, dct, pvt) {
+		if (!csrow_enabled(csrow, dct, pvt))
 			continue;
 
-		/*
-		 * We have an ENABLED CSROW, Isolate just the MASK bits of the
-		 * target: [28:19] and [13:5], which map to [36:27] and [21:13]
-		 * of the actual address.
-		 */
-		cs_base &= REV_F_F1Xh_DCSB_BASE_BITS;
+		get_cs_base_and_mask(pvt, csrow, dct, &cs_base, &cs_mask);
 
-		/*
-		 * Get the DCT Mask, and ENABLE the reserved bits: [18:16] and
-		 * [4:0] to become ON. Then mask off bits [28:0] ([36:8])
-		 */
-		cs_mask = amd64_get_dct_mask(pvt, cs, csrow);
+		debugf1("    CSROW=%d CSBase=0x%llx CSMask=0x%llx\n",
+			csrow, cs_base, cs_mask);
 
-		debugf1("    CSROW=%d CSBase=0x%x RAW CSMask=0x%x\n",
-				csrow, cs_base, cs_mask);
+		cs_mask = ~cs_mask;
 
-		cs_mask = (cs_mask | 0x0007C01F) & 0x1FFFFFFF;
+		debugf1("    (InputAddr & ~CSMask)=0x%llx "
+			"(CSBase & ~CSMask)=0x%llx\n",
+			(in_addr & cs_mask), (cs_base & cs_mask));
 
-		debugf1("              Final CSMask=0x%x\n", cs_mask);
-		debugf1("    (InputAddr & ~CSMask)=0x%x "
-				"(CSBase & ~CSMask)=0x%x\n",
-				(in_addr & ~cs_mask), (cs_base & ~cs_mask));
-
-		if ((in_addr & ~cs_mask) == (cs_base & ~cs_mask)) {
-			cs_found = f10_process_possible_spare(csrow, cs, pvt);
+		if ((in_addr & cs_mask) == (cs_base & cs_mask)) {
+			cs_found = f10_process_possible_spare(pvt, dct, csrow);
 
 			debugf1(" MATCH csrow=%d\n", cs_found);
 			break;
@@ -1434,10 +1360,11 @@ static int f10_match_to_this_node(struct amd64_pvt *pvt, int range,
 				  u64 sys_addr, int *nid, int *chan_sel)
 {
 	int cs_found = -EINVAL, high_range = 0;
-	u32 intlv_shift;
-	u64 hole_off;
-	u32 hole_valid, tmp, dct_sel_base, channel;
 	u64 chan_addr, dct_sel_base_off;
+	u64 hole_off;
+	u32 hole_valid, tmp, dct_sel_base;
+	u32 intlv_shift;
+	u8 channel;
 
 	u8 node_id    = dram_dst_node(pvt, range);
 	u32 intlv_en  = dram_intlv_en(pvt, range);
@@ -1499,10 +1426,9 @@ static int f10_match_to_this_node(struct amd64_pvt *pvt, int range,
 		}
 	}
 
-	debugf1("   (ChannelAddrLong=0x%llx) >> 8 becomes InputAddr=0x%x\n",
-		chan_addr, (u32)(chan_addr >> 8));
+	debugf1("   (ChannelAddrLong=0x%llx)\n", chan_addr);
 
-	cs_found = f10_lookup_addr_in_dct(chan_addr >> 8, node_id, channel);
+	cs_found = f10_lookup_addr_in_dct(chan_addr, node_id, channel);
 
 	if (cs_found >= 0) {
 		*nid = node_id;
@@ -1603,7 +1529,8 @@ static void amd64_debug_display_dimm_sizes(int ctrl, struct amd64_pvt *pvt)
 	}
 
 	dbam = (ctrl && !dct_ganging_enabled(pvt)) ? pvt->dbam1 : pvt->dbam0;
-	dcsb = (ctrl && !dct_ganging_enabled(pvt)) ? pvt->dcsb1 : pvt->dcsb0;
+	dcsb = (ctrl && !dct_ganging_enabled(pvt)) ? pvt->csels[1].csbases
+						   : pvt->csels[0].csbases;
 
 	debugf1("F2x%d80 (DRAM Bank Address Mapping): 0x%08x\n", ctrl, dbam);
 
@@ -1613,11 +1540,11 @@ static void amd64_debug_display_dimm_sizes(int ctrl, struct amd64_pvt *pvt)
 	for (dimm = 0; dimm < 4; dimm++) {
 
 		size0 = 0;
-		if (dcsb[dimm*2] & K8_DCSB_CS_ENABLE)
+		if (dcsb[dimm*2] & DCSB_CS_ENABLE)
 			size0 = pvt->ops->dbam_to_cs(pvt, DBAM_DIMM(dimm, dbam));
 
 		size1 = 0;
-		if (dcsb[dimm*2 + 1] & K8_DCSB_CS_ENABLE)
+		if (dcsb[dimm*2 + 1] & DCSB_CS_ENABLE)
 			size1 = pvt->ops->dbam_to_cs(pvt, DBAM_DIMM(dimm, dbam));
 
 		amd64_info(EDAC_MC ": %d: %5dMB %d: %5dMB\n",
@@ -2082,7 +2009,7 @@ static void read_mc_regs(struct amd64_pvt *pvt)
  * NOTE: CPU Revision Dependent code
  *
  * Input:
- *	@csrow_nr ChipSelect Row Number (0..pvt->cs_count-1)
+ *	@csrow_nr ChipSelect Row Number (0..NUM_CHIPSELECTS-1)
  *	k8 private pointer to -->
  *			DRAM Bank Address mapping register
  *			node_id
@@ -2148,7 +2075,7 @@ static int init_csrows(struct mem_ctl_info *mci)
 {
 	struct csrow_info *csrow;
 	struct amd64_pvt *pvt = mci->pvt_info;
-	u64 input_addr_min, input_addr_max, sys_addr;
+	u64 input_addr_min, input_addr_max, sys_addr, base, mask;
 	u32 val;
 	int i, empty = 1;
 
@@ -2161,10 +2088,10 @@ static int init_csrows(struct mem_ctl_info *mci)
 		pvt->mc_node_id, val,
 		!!(val & K8_NBCFG_CHIPKILL), !!(val & K8_NBCFG_ECC_ENABLE));
 
-	for (i = 0; i < pvt->cs_count; i++) {
+	for_each_chip_select(i, 0, pvt) {
 		csrow = &mci->csrows[i];
 
-		if ((pvt->dcsb0[i] & K8_DCSB_CS_ENABLE) == 0) {
+		if (!csrow_enabled(i, 0, pvt)) {
 			debugf1("----CSROW %d EMPTY for node %d\n", i,
 				pvt->mc_node_id);
 			continue;
@@ -2180,7 +2107,9 @@ static int init_csrows(struct mem_ctl_info *mci)
 		csrow->first_page = (u32) (sys_addr >> PAGE_SHIFT);
 		sys_addr = input_addr_to_sys_addr(mci, input_addr_max);
 		csrow->last_page = (u32) (sys_addr >> PAGE_SHIFT);
-		csrow->page_mask = ~mask_from_dct_mask(pvt, i);
+
+		get_cs_base_and_mask(pvt, i, 0, &base, &mask);
+		csrow->page_mask = ~mask;
 		/* 8 bytes of resolution */
 
 		csrow->mtype = amd64_determine_memory_type(pvt, i);
@@ -2532,7 +2461,7 @@ static int amd64_init_one_instance(struct pci_dev *F2)
 		goto err_siblings;
 
 	ret = -ENOMEM;
-	mci = edac_mc_alloc(0, pvt->cs_count, pvt->channel_count, nid);
+	mci = edac_mc_alloc(0, pvt->csels[0].b_cnt, pvt->channel_count, nid);
 	if (!mci)
 		goto err_siblings;
 
diff --git a/drivers/edac/amd64_edac.h b/drivers/edac/amd64_edac.h
index a2bc9a650fff..1964f89a28bc 100644
--- a/drivers/edac/amd64_edac.h
+++ b/drivers/edac/amd64_edac.h
@@ -159,6 +159,14 @@
 #define ON true
 #define OFF false
 
+/*
+ * Create a contiguous bitmask starting at bit position @lo and ending at
+ * position @hi. For example
+ *
+ * GENMASK(21, 39) gives us the 64bit vector 0x000000ffffe00000.
+ */
+#define GENMASK(lo, hi)			(((1ULL << ((hi) - (lo) + 1)) - 1) << (lo))
+
 /*
  * PCI-defined configuration space registers
  */
@@ -198,45 +206,14 @@
 /*
  * Function 2 - DRAM controller
  */
-#define K8_DCSB0			0x40
-#define F10_DCSB1			0x140
+#define DCSB0				0x40
+#define DCSB1				0x140
+#define DCSB_CS_ENABLE			BIT(0)
 
-#define K8_DCSB_CS_ENABLE		BIT(0)
-#define K8_DCSB_NPT_SPARE		BIT(1)
-#define K8_DCSB_NPT_TESTFAIL		BIT(2)
+#define DCSM0				0x60
+#define DCSM1				0x160
 
-/*
- * REV E: select [31:21] and [15:9] from DCSB and the shift amount to form
- * the address
- */
-#define REV_E_DCSB_BASE_BITS		(0xFFE0FE00ULL)
-#define REV_E_DCS_SHIFT			4
-
-#define REV_F_F1Xh_DCSB_BASE_BITS	(0x1FF83FE0ULL)
-#define REV_F_F1Xh_DCS_SHIFT		8
-
-/*
- * REV F and later: selects [28:19] and [13:5] from DCSB and the shift amount
- * to form the address
- */
-#define REV_F_DCSB_BASE_BITS		(0x1FF83FE0ULL)
-#define REV_F_DCS_SHIFT			8
-
-/* DRAM CS Mask Registers */
-#define K8_DCSM0			0x60
-#define F10_DCSM1			0x160
-
-/* REV E: select [29:21] and [15:9] from DCSM */
-#define REV_E_DCSM_MASK_BITS		0x3FE0FE00
-
-/* unused bits [24:20] and [12:0] */
-#define REV_E_DCS_NOTUSED_BITS		0x01F01FFF
-
-/* REV F and later: select [28:19] and [13:5] from DCSM */
-#define REV_F_F1Xh_DCSM_MASK_BITS	0x1FF83FE0
-
-/* unused bits [26:22] and [12:0] */
-#define REV_F_F1Xh_DCS_NOTUSED_BITS	0x07C01FFF
+#define csrow_enabled(i, dct, pvt)	((pvt)->csels[(dct)].csbases[(i)] & DCSB_CS_ENABLE)
 
 #define DBAM0				0x80
 #define DBAM1				0x180
@@ -412,6 +389,15 @@ struct dram_range {
 	struct reg_pair lim;
 };
 
+/* A DCT chip selects collection */
+struct chip_select {
+	u32 csbases[NUM_CHIPSELECTS];
+	u8 b_cnt;
+
+	u32 csmasks[NUM_CHIPSELECTS];
+	u8 m_cnt;
+};
+
 struct amd64_pvt {
 	struct low_ops *ops;
 
@@ -434,29 +420,12 @@ struct amd64_pvt {
 	u32 dbam0;		/* DRAM Base Address Mapping reg for DCT0 */
 	u32 dbam1;		/* DRAM Base Address Mapping reg for DCT1 */
 
-	/* DRAM CS Base Address Registers F2x[1,0][5C:40] */
-	u32 dcsb0[NUM_CHIPSELECTS];
-	u32 dcsb1[NUM_CHIPSELECTS];
-
-	/* DRAM CS Mask Registers F2x[1,0][6C:60] */
-	u32 dcsm0[NUM_CHIPSELECTS];
-	u32 dcsm1[NUM_CHIPSELECTS];
+	/* one for each DCT */
+	struct chip_select csels[2];
 
 	/* DRAM base and limit pairs F1x[78,70,68,60,58,50,48,40] */
 	struct dram_range ranges[DRAM_RANGES];
 
-	/*
-	 * The following fields are set at (load) run time, after CPU revision
-	 * has been determined, since the dct_base and dct_mask registers vary
-	 * based on revision
-	 */
-	u32 dcsb_base;		/* DCSB base bits */
-	u32 dcsm_mask;		/* DCSM mask bits */
-	u32 cs_count;		/* num chip selects (== num DCSB registers) */
-	u32 num_dcsm;		/* Number of DCSM registers */
-	u32 dcs_mask_notused;	/* DCSM notused mask bits */
-	u32 dcs_shift;		/* DCSB and DCSM shift value */
-
 	u64 top_mem;		/* top of memory below 4GB */
 	u64 top_mem2;		/* top of memory above 4GB */