New patch to review for coreboot: 06c444f AMD K8 fam10: Eliminate local variable min_bus

[Kyösti Mälkki]

Kyösti Mälkki ([e-mail]) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/8364

-gerrit

commit 06c444f683061dae1432ce488a8df118e4e27452
Author: Kyösti Mälkki 
Date:   Thu Feb 5 08:12:20 2015 +0200

AMD K8 fam10: Eliminate local variable min_bus

Some cases of max==0xff wrapping around the 8-bit link->secondary
    register remain to be solved.

Change-Id: I01e2ab6b2f23a03dbac49207ab584eccd1ca9b1f
    Signed-off-by: Kyösti Mälkki 
---
 src/northbridge/amd/amdfam10/northbridge.c | 19 +++++++------------
 src/northbridge/amd/amdk8/northbridge.c    | 16 +++++++---------
 2 files changed, 14 insertions(+), 21 deletions(-)

diff --git a/src/northbridge/amd/amdfam10/northbridge.c b/src/northbridge/amd/amdfam10/northbridge.c
index 287f468..a81dd82 100644
--- a/src/northbridge/amd/amdfam10/northbridge.c
+++ b/src/northbridge/amd/amdfam10/northbridge.c
@@ -166,7 +166,6 @@ static u32 amdfam10_scan_chain(device_t dev, u32 nodeid, struct bus *link, bool
    	int i;
    	u32 ht_c_index;
    	u32 ht_unitid_base[4]; // here assume only 4 HT device on chain
-		u32 min_bus;
    	u32 busses;
    	u32 max_devfn;

@@ -198,25 +197,21 @@ static u32 amdfam10_scan_chain(device_t dev, u32 nodeid, struct bus *link, bool
    	 */

if (CONFIG_SB_HT_CHAIN_ON_BUS0 == 0) {
-			min_bus = ++max;
+			max++;
    	} else if (is_sblink) {
-			// first chain will on bus 0
-			min_bus = max;  /* actually max is 0 here */
+
    	} else if (CONFIG_SB_HT_CHAIN_ON_BUS0 == 1) {
-			min_bus = ++max;
+			max++;
    	} else if (CONFIG_SB_HT_CHAIN_ON_BUS0 > 1) {
-			// second chain will be on 0x40, third 0x80, forth 0xc0
-			// i would refined that to  2, 3, 4 ==> 0, 0x, 40, 0x80, 0xc0
-			//   >4 will use more segments,
    		// We can have 16 segmment and every segment have 256 bus,
    		// For that case need the kernel support mmio pci config.

// one node can have 8 link and segn is the same
-			min_bus = (((max & 0xff)>>3) + 1) << 3;
-			max = (max & ~0xff) | min_bus;
+			max++;
+			max = ALIGN_UP(max, 8);
    	}

-		link->secondary = min_bus;
+		link->secondary = max;
    	link->subordinate = (max & ~0xff) | 0xfc;

/* Read the existing primary/secondary/subordinate bus
@@ -245,7 +240,7 @@ static u32 amdfam10_scan_chain(device_t dev, u32 nodeid, struct bus *link, bool
    	}

//if ext conf is enabled, only need use 0x1f
-		if (min_bus == 0)
+		if (link->secondary == 0)
    		max_devfn = (0x17<<3) | 7;
    	else
    		max_devfn = (0x1f<<3) | 7;
diff --git a/src/northbridge/amd/amdk8/northbridge.c b/src/northbridge/amd/amdk8/northbridge.c
index d96e113..8fe38ff 100644
--- a/src/northbridge/amd/amdk8/northbridge.c
+++ b/src/northbridge/amd/amdk8/northbridge.c
@@ -93,7 +93,6 @@ static u32 amdk8_scan_chain(device_t dev, u32 nodeid, struct bus *link, bool is_
    	u32 busses, config_busses;
    	u32 free_reg, config_reg;
    	u32 ht_unitid_base[4]; // here assume only 4 HT device on chain
-		u32 min_bus;
    	u32 max_devfn;

link->cap = 0x80 + (link->link_num * 0x20);
@@ -141,19 +140,18 @@ static u32 amdk8_scan_chain(device_t dev, u32 nodeid, struct bus *link, bool is_
    	 * so we set the subordinate bus number to 0xff for the moment.
    	 */
    	if (CONFIG_SB_HT_CHAIN_ON_BUS0 == 0) {
-			min_bus = ++max;
+			max++;
    	} else if (is_sblink) {
-			// first chain will on bus 0
-			min_bus = max;  /* actually max is 0 here */
+
    	} else if (CONFIG_SB_HT_CHAIN_ON_BUS0 == 1) {
-			min_bus = ++max;
+			max++;
    	} else if (CONFIG_SB_HT_CHAIN_ON_BUS0 > 1) {
    		// second chain will be on 0x40, third 0x80, forth 0xc0
-			min_bus = (max & ~0x3f) + 0x40;
-			max = min_bus;
+			max++;
+			max = ALIGN_UP(max, 0x40);
    	}

-		link->secondary = min_bus;
+		link->secondary = max;
    	link->subordinate = 0xff;

/* Read the existing primary/secondary/subordinate bus
@@ -188,7 +186,7 @@ static u32 amdk8_scan_chain(device_t dev, u32 nodeid, struct bus *link, bool is_
    		ht_unitid_base[i] = 0x20;
    	}

-		if (min_bus == 0)
+		if (link->secondary == 0)
    		max_devfn = (0x17<<3) | 7;
    	else
    		max_devfn = (0x1f<<3) | 7;