mpc83xx: Cleanup usage of DDR constants

Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>
Cc: Joe Hershberger <joe.hershberger@gmail.com>
Signed-off-by: Kim Phillips <kim.phillips@freescale.com>

13 files changed, 111 insertions, 48 deletions

diff --git a/include/configs/MPC8308RDB.h b/include/configs/MPC8308RDB.h
index 8f0835f..334c96e 100644
--- a/include/configs/MPC8308RDB.h
+++ b/include/configs/MPC8308RDB.h
@@ -149,7 +149,8 @@
 
 #define CONFIG_SYS_DDR_CS0_BNDS	0x00000007
 #define CONFIG_SYS_DDR_CS0_CONFIG	(CSCONFIG_EN \
-				| 0x00010000  /* ODT_WR to CSn */ \
+				| CSCONFIG_ODT_RD_NEVER \
+				| CSCONFIG_ODT_WR_ONLY_CURRENT \
 				| CSCONFIG_ROW_BIT_13 | CSCONFIG_COL_BIT_10)
 				/* 0x80010102 */
 #define CONFIG_SYS_DDR_TIMING_3	0x00000000
@@ -184,7 +185,7 @@
 				/* 0x03600100 */
 #define CONFIG_SYS_DDR_SDRAM_CFG	(SDRAM_CFG_SREN \
 				| SDRAM_CFG_SDRAM_TYPE_DDR2 \
-				| SDRAM_CFG_32_BE)
+				| SDRAM_CFG_DBW_32)
 				/* 0x43080000 */
 
 #define CONFIG_SYS_DDR_SDRAM_CFG2	0x00401000 /* 1 posted refresh */
diff --git a/include/configs/MPC8313ERDB.h b/include/configs/MPC8313ERDB.h
index b2af4f9..93e1b1b 100644
--- a/include/configs/MPC8313ERDB.h
+++ b/include/configs/MPC8313ERDB.h
@@ -131,7 +131,8 @@
  */
 #define CONFIG_SYS_DDR_SIZE	128		/* MB */
 #define CONFIG_SYS_DDR_CONFIG	(CSCONFIG_EN \
-				| 0x00010000	/* TODO */ \
+				| CSCONFIG_ODT_RD_NEVER \
+				| CSCONFIG_ODT_WR_ONLY_CURRENT \
 				| CSCONFIG_ROW_BIT_13 \
 				| CSCONFIG_COL_BIT_10)
 				/* 0x80010102 */
@@ -169,12 +170,13 @@
 #if defined(CONFIG_DDR_2T_TIMING)
 #define CONFIG_SYS_SDRAM_CFG	(SDRAM_CFG_SREN \
 				| SDRAM_CFG_SDRAM_TYPE_DDR2 \
-				| SDRAM_CFG_2T_EN \
-				| SDRAM_CFG_DBW_32)
+				| SDRAM_CFG_DBW_32 \
+				| SDRAM_CFG_2T_EN)
+				/* 0x43088000 */
 #else
 #define CONFIG_SYS_SDRAM_CFG	(SDRAM_CFG_SREN \
 				| SDRAM_CFG_SDRAM_TYPE_DDR2 \
-				| SDRAM_CFG_32_BE)
+				| SDRAM_CFG_DBW_32)
 				/* 0x43080000 */
 #endif
 #define CONFIG_SYS_SDRAM_CFG2		0x00401000
diff --git a/include/configs/MPC8315ERDB.h b/include/configs/MPC8315ERDB.h
index 2305215..0ae1d99 100644
--- a/include/configs/MPC8315ERDB.h
+++ b/include/configs/MPC8315ERDB.h
@@ -141,7 +141,8 @@
 #define CONFIG_SYS_DDR_SIZE		128 /* MB */
 #define CONFIG_SYS_DDR_CS0_BNDS	0x00000007
 #define CONFIG_SYS_DDR_CS0_CONFIG	(CSCONFIG_EN \
-				| 0x00010000  /* ODT_WR to CSn */ \
+				| CSCONFIG_ODT_RD_NEVER \
+				| CSCONFIG_ODT_WR_ONLY_CURRENT \
 				| CSCONFIG_ROW_BIT_13 \
 				| CSCONFIG_COL_BIT_10)
 				/* 0x80010102 */
@@ -177,7 +178,7 @@
 				/* 0x03600100 */
 #define CONFIG_SYS_DDR_SDRAM_CFG	(SDRAM_CFG_SREN \
 				| SDRAM_CFG_SDRAM_TYPE_DDR2 \
-				| SDRAM_CFG_32_BE)
+				| SDRAM_CFG_DBW_32)
 				/* 0x43080000 */
 #define CONFIG_SYS_DDR_SDRAM_CFG2	0x00401000 /* 1 posted refresh */
 #define CONFIG_SYS_DDR_MODE		((0x0448 << SDRAM_MODE_ESD_SHIFT) \
diff --git a/include/configs/MPC8323ERDB.h b/include/configs/MPC8323ERDB.h
index b830a98..28c61ca 100644
--- a/include/configs/MPC8323ERDB.h
+++ b/include/configs/MPC8323ERDB.h
@@ -78,7 +78,6 @@
 #define CONFIG_SYS_DDR_BASE	0x00000000	/* DDR is system memory */
 #define CONFIG_SYS_SDRAM_BASE	CONFIG_SYS_DDR_BASE
 #define CONFIG_SYS_DDR_SDRAM_BASE	CONFIG_SYS_DDR_BASE
-#define CONFIG_SYS_DDRCDR	0x73000002	/* DDR II voltage is 1.8V */
 
 #undef CONFIG_SPD_EEPROM
 #if defined(CONFIG_SPD_EEPROM)
@@ -90,7 +89,6 @@
  */
 #define CONFIG_SYS_DDR_SIZE	64	/* MB */
 #define CONFIG_SYS_DDR_CS0_CONFIG	(CSCONFIG_EN \
-				| CSCONFIG_ODT_WR_ACS \
 				| CSCONFIG_ROW_BIT_13 \
 				| CSCONFIG_COL_BIT_9)
 				/* 0x80010101 */
diff --git a/include/configs/MPC832XEMDS.h b/include/configs/MPC832XEMDS.h
index 40a1e0e..d552046 100644
--- a/include/configs/MPC832XEMDS.h
+++ b/include/configs/MPC832XEMDS.h
@@ -111,17 +111,53 @@
 /* Manually set up DDR parameters
  */
 #define CONFIG_SYS_DDR_SIZE		128	/* MB */
-#define CONFIG_SYS_DDR_CS0_CONFIG	0x80840102
-#define CONFIG_SYS_DDR_TIMING_0		0x00220802
-#define CONFIG_SYS_DDR_TIMING_1		0x3935d322
-#define CONFIG_SYS_DDR_TIMING_2		0x0f9048ca
+#define CONFIG_SYS_DDR_CS0_CONFIG	(CSCONFIG_EN \
+					| CSCONFIG_AP \
+					| CSCONFIG_ODT_WR_CFG \
+					| CSCONFIG_ROW_BIT_13 \
+					| CSCONFIG_COL_BIT_10)
+					/* 0x80840102 */
+#define CONFIG_SYS_DDR_TIMING_0		((0 << TIMING_CFG0_RWT_SHIFT) \
+					| (0 << TIMING_CFG0_WRT_SHIFT) \
+					| (0 << TIMING_CFG0_RRT_SHIFT) \
+					| (0 << TIMING_CFG0_WWT_SHIFT) \
+					| (2 << TIMING_CFG0_ACT_PD_EXIT_SHIFT) \
+					| (2 << TIMING_CFG0_PRE_PD_EXIT_SHIFT) \
+					| (8 << TIMING_CFG0_ODT_PD_EXIT_SHIFT) \
+					| (2 << TIMING_CFG0_MRS_CYC_SHIFT))
+					/* 0x00220802 */
+#define CONFIG_SYS_DDR_TIMING_1		((3 << TIMING_CFG1_PRETOACT_SHIFT) \
+					| (9 << TIMING_CFG1_ACTTOPRE_SHIFT) \
+					| (3 << TIMING_CFG1_ACTTORW_SHIFT) \
+					| (5 << TIMING_CFG1_CASLAT_SHIFT) \
+					| (13 << TIMING_CFG1_REFREC_SHIFT) \
+					| (3 << TIMING_CFG1_WRREC_SHIFT) \
+					| (2 << TIMING_CFG1_ACTTOACT_SHIFT) \
+					| (2 << TIMING_CFG1_WRTORD_SHIFT))
+					/* 0x3935D322 */
+#define CONFIG_SYS_DDR_TIMING_2		((0 << TIMING_CFG2_ADD_LAT_SHIFT) \
+				| (31 << TIMING_CFG2_CPO_SHIFT) \
+				| (2 << TIMING_CFG2_WR_LAT_DELAY_SHIFT) \
+				| (2 << TIMING_CFG2_RD_TO_PRE_SHIFT) \
+				| (2 << TIMING_CFG2_WR_DATA_DELAY_SHIFT) \
+				| (3 << TIMING_CFG2_CKE_PLS_SHIFT) \
+				| (10 << TIMING_CFG2_FOUR_ACT_SHIFT))
+				/* 0x0F9048CA */
 #define CONFIG_SYS_DDR_TIMING_3		0x00000000
-#define CONFIG_SYS_DDR_CLK_CNTL		0x02000000
-#define CONFIG_SYS_DDR_MODE		0x44400232
+#define CONFIG_SYS_DDR_CLK_CNTL		DDR_SDRAM_CLK_CNTL_CLK_ADJUST_05
+					/* 0x02000000 */
+#define CONFIG_SYS_DDR_MODE		((0x4440 << SDRAM_MODE_ESD_SHIFT) \
+					| (0x0232 << SDRAM_MODE_SD_SHIFT))
+					/* 0x44400232 */
 #define CONFIG_SYS_DDR_MODE2		0x8000c000
-#define CONFIG_SYS_DDR_INTERVAL		0x03200064
+#define CONFIG_SYS_DDR_INTERVAL		((800 << SDRAM_INTERVAL_REFINT_SHIFT) \
+					| (100 << SDRAM_INTERVAL_BSTOPRE_SHIFT))
+					/* 0x03200064 */
 #define CONFIG_SYS_DDR_CS0_BNDS		0x00000007
-#define CONFIG_SYS_DDR_SDRAM_CFG	0x43080000
+#define CONFIG_SYS_DDR_SDRAM_CFG	(SDRAM_CFG_SREN \
+					| SDRAM_CFG_SDRAM_TYPE_DDR2 \
+					| SDRAM_CFG_32_BE)
+					/* 0x43080000 */
 #define CONFIG_SYS_DDR_SDRAM_CFG2	0x00401000
 #endif
 
diff --git a/include/configs/MPC8360ERDK.h b/include/configs/MPC8360ERDK.h
index 04ea738..bc574a6 100644
--- a/include/configs/MPC8360ERDK.h
+++ b/include/configs/MPC8360ERDK.h
@@ -96,7 +96,10 @@
 /*
  * DDRCDR - DDR Control Driver Register
  */
-#define CONFIG_SYS_DDRCDR_VALUE	0x80080001
+#define CONFIG_SYS_DDRCDR_VALUE	(DDRCDR_DHC_EN \
+				| DDRCDR_ODT \
+				| DDRCDR_Q_DRN)
+				/* 0x80080001 */
 
 #undef CONFIG_SPD_EEPROM	/* Do not use SPD EEPROM for DDR setup */
 
@@ -105,11 +108,11 @@
  */
 #define CONFIG_DDR_II
 #define CONFIG_SYS_DDR_SIZE		256 /* MB */
-#define CONFIG_SYS_DDR_CS0_BNDS	0x0000000f
+#define CONFIG_SYS_DDR_CS0_BNDS		0x0000000f
 #define CONFIG_SYS_DDR_CS0_CONFIG	(CSCONFIG_EN \
 					| CSCONFIG_ROW_BIT_13 \
 					| CSCONFIG_COL_BIT_10 \
-					| CSCONFIG_ODT_WR_ACS)
+					| CSCONFIG_ODT_WR_ONLY_CURRENT)
 #define CONFIG_SYS_DDR_SDRAM_CFG	(SDRAM_CFG_SDRAM_TYPE_DDR2 \
 					| SDRAM_CFG_ECC_EN)
 #define CONFIG_SYS_DDR_SDRAM_CFG2	0x00001000
diff --git a/include/configs/MPC837XEMDS.h b/include/configs/MPC837XEMDS.h
index dc4d877..8c2af08 100644
--- a/include/configs/MPC837XEMDS.h
+++ b/include/configs/MPC837XEMDS.h
@@ -128,7 +128,10 @@
 #define CONFIG_SYS_DDR_SDRAM_BASE	CONFIG_SYS_DDR_BASE
 #define CONFIG_SYS_DDR_SDRAM_CLK_CNTL	DDR_SDRAM_CLK_CNTL_CLK_ADJUST_05
 #define CONFIG_SYS_83XX_DDR_USES_CS0
-#define CONFIG_SYS_DDRCDR_VALUE	0x80080001 /* ODT 150ohm on SoC */
+#define CONFIG_SYS_DDRCDR_VALUE		(DDRCDR_DHC_EN \
+					| DDRCDR_ODT \
+					| DDRCDR_Q_DRN)
+					/* 0x80080001 */ /* ODT 150ohm on SoC */
 
 #undef CONFIG_DDR_ECC		/* support DDR ECC function */
 #undef CONFIG_DDR_ECC_CMD	/* Use DDR ECC user commands */
@@ -147,10 +150,11 @@
 #define CONFIG_SYS_DDR_SIZE		512 /* MB */
 #define CONFIG_SYS_DDR_CS0_BNDS	0x0000001f
 #define CONFIG_SYS_DDR_CS0_CONFIG	(CSCONFIG_EN \
-				| 0x00010000  /* ODT_WR to CSn */ \
-				| CSCONFIG_ROW_BIT_14 \
-				| CSCONFIG_COL_BIT_10)
-				/* 0x80010202 */
+			| CSCONFIG_ODT_RD_NEVER  /* ODT_RD to none */ \
+			| CSCONFIG_ODT_WR_ONLY_CURRENT  /* ODT_WR to CSn */ \
+			| CSCONFIG_ROW_BIT_14 \
+			| CSCONFIG_COL_BIT_10)
+			/* 0x80010202 */
 #define CONFIG_SYS_DDR_TIMING_3	0x00000000
 #define CONFIG_SYS_DDR_TIMING_0	((0 << TIMING_CFG0_RWT_SHIFT) \
 				| (0 << TIMING_CFG0_WRT_SHIFT) \
diff --git a/include/configs/MPC837XERDB.h b/include/configs/MPC837XERDB.h
index 371fff7..bf8a94d 100644
--- a/include/configs/MPC837XERDB.h
+++ b/include/configs/MPC837XERDB.h
@@ -165,9 +165,11 @@
  * Manually set up DDR parameters
  */
 #define CONFIG_SYS_DDR_SIZE		256		/* MB */
-#define CONFIG_SYS_DDR_CS0_BNDS	0x0000000f
-#define CONFIG_SYS_DDR_CS0_CONFIG	(CSCONFIG_EN | CSCONFIG_ODT_WR_ACS \
-				| CSCONFIG_ROW_BIT_13 | CSCONFIG_COL_BIT_10)
+#define CONFIG_SYS_DDR_CS0_BNDS		0x0000000f
+#define CONFIG_SYS_DDR_CS0_CONFIG	(CSCONFIG_EN \
+					| CSCONFIG_ODT_WR_ONLY_CURRENT \
+					| CSCONFIG_ROW_BIT_13 \
+					| CSCONFIG_COL_BIT_10)
 
 #define CONFIG_SYS_DDR_TIMING_3	0x00000000
 #define CONFIG_SYS_DDR_TIMING_0	((0 << TIMING_CFG0_RWT_SHIFT) \
@@ -178,7 +180,6 @@
 				| (6 << TIMING_CFG0_PRE_PD_EXIT_SHIFT) \
 				| (8 << TIMING_CFG0_ODT_PD_EXIT_SHIFT) \
 				| (2 << TIMING_CFG0_MRS_CYC_SHIFT))
-				/* 0x00220802 */
 				/* 0x00260802 */ /* DDR400 */
 #define CONFIG_SYS_DDR_TIMING_1	((3 << TIMING_CFG1_PRETOACT_SHIFT) \
 				| (9 << TIMING_CFG1_ACTTOPRE_SHIFT) \
@@ -188,9 +189,15 @@
 				| (3 << TIMING_CFG1_WRREC_SHIFT) \
 				| (2 << TIMING_CFG1_ACTTOACT_SHIFT) \
 				| (2 << TIMING_CFG1_WRTORD_SHIFT))
-				/* 0x3935d322 */
 				/* 0x3937d322 */
-#define CONFIG_SYS_DDR_TIMING_2	0x02984cc8
+#define CONFIG_SYS_DDR_TIMING_2	((0 << TIMING_CFG2_ADD_LAT_SHIFT) \
+				| (5 << TIMING_CFG2_CPO_SHIFT) \
+				| (3 << TIMING_CFG2_WR_LAT_DELAY_SHIFT) \
+				| (2 << TIMING_CFG2_RD_TO_PRE_SHIFT) \
+				| (3 << TIMING_CFG2_WR_DATA_DELAY_SHIFT) \
+				| (3 << TIMING_CFG2_CKE_PLS_SHIFT) \
+				| (8 << TIMING_CFG2_FOUR_ACT_SHIFT))
+				/* 0x02984cc8 */
 
 #define CONFIG_SYS_DDR_INTERVAL	((1024 << SDRAM_INTERVAL_REFINT_SHIFT) \
 				| (0 << SDRAM_INTERVAL_BSTOPRE_SHIFT))
@@ -198,12 +205,13 @@
 
 #if defined(CONFIG_DDR_2T_TIMING)
 #define CONFIG_SYS_DDR_SDRAM_CFG	(SDRAM_CFG_SREN \
-					| 3 << SDRAM_CFG_SDRAM_TYPE_SHIFT \
-					| SDRAM_CFG_2T_EN \
-					| SDRAM_CFG_DBW_32)
+					| SDRAM_CFG_SDRAM_TYPE_DDR2 \
+					| SDRAM_CFG_32_BE \
+					| SDRAM_CFG_2T_EN)
+					/* 0x43088000 */
 #else
 #define CONFIG_SYS_DDR_SDRAM_CFG	(SDRAM_CFG_SREN \
-					| 3 << SDRAM_CFG_SDRAM_TYPE_SHIFT)
+					| SDRAM_CFG_SDRAM_TYPE_DDR2)
 					/* 0x43000000 */
 #endif
 #define CONFIG_SYS_DDR_SDRAM_CFG2	0x00001000 /* 1 posted refresh */
diff --git a/include/configs/MVBLM7.h b/include/configs/MVBLM7.h
index 32cc929..f0d4e80 100644
--- a/include/configs/MVBLM7.h
+++ b/include/configs/MVBLM7.h
@@ -72,7 +72,10 @@
 #define CONFIG_SYS_MEMTEST_END		(70<<20)
 #define CONFIG_VERY_BIG_RAM
 
-#define CONFIG_SYS_DDRCDR		0x22000001
+#define CONFIG_SYS_DDRCDR		(DDRCDR_PZ_HIZ \
+					| DDRCDR_NZ_HIZ \
+					| DDRCDR_Q_DRN)
+					/* 0x22000001 */
 #define CONFIG_SYS_DDR_SDRAM_CLK_CNTL	DDR_SDRAM_CLK_CNTL_CLK_ADJUST_05
 
 #define CONFIG_SYS_DDR_SIZE		512
diff --git a/include/configs/kmeter1.h b/include/configs/kmeter1.h
index 5f68dc9..c04bde9 100644
--- a/include/configs/kmeter1.h
+++ b/include/configs/kmeter1.h
@@ -72,9 +72,10 @@
 #define CONFIG_SYS_DDR_CS0_CONFIG	(CSCONFIG_EN | CSCONFIG_AP | \
 					 CSCONFIG_ROW_BIT_13 | \
 					 CSCONFIG_COL_BIT_10 | \
-					 CSCONFIG_ODT_WR_ACS)
+					 CSCONFIG_ODT_WR_ONLY_CURRENT)
 
-#define	CONFIG_SYS_DDRCDR		0x40000001
+#define	CONFIG_SYS_DDRCDR		(DDRCDR_EN | DDRCDR_Q_DRN)
+					/* 0x40000001 */
 #define CONFIG_SYS_DDR_MODE		0x47860452
 #define CONFIG_SYS_DDR_MODE2		0x8080c000
 
diff --git a/include/configs/mpc8308_p1m.h b/include/configs/mpc8308_p1m.h
index c409acb..fbce800 100644
--- a/include/configs/mpc8308_p1m.h
+++ b/include/configs/mpc8308_p1m.h
@@ -157,9 +157,11 @@
 
 #define CONFIG_SYS_DDR_CS0_BNDS	0x00000007
 #define CONFIG_SYS_DDR_CS0_CONFIG	(CSCONFIG_EN \
-				| 0x00010000  /* ODT_WR to CSn */ \
-				| CSCONFIG_ROW_BIT_13 | CSCONFIG_COL_BIT_10)
-				/* 0x80010102 */
+					| CSCONFIG_ODT_RD_NEVER \
+					| CSCONFIG_ODT_WR_ONLY_CURRENT \
+					| CSCONFIG_ROW_BIT_13 \
+					| CSCONFIG_COL_BIT_10)
+					/* 0x80010102 */
 #define CONFIG_SYS_DDR_TIMING_3	0x00000000
 #define CONFIG_SYS_DDR_TIMING_0	((0 << TIMING_CFG0_RWT_SHIFT) \
 				| (0 << TIMING_CFG0_WRT_SHIFT) \
@@ -192,7 +194,7 @@
 				/* 0x03600100 */
 #define CONFIG_SYS_DDR_SDRAM_CFG	(SDRAM_CFG_SREN \
 				| SDRAM_CFG_SDRAM_TYPE_DDR2 \
-				| SDRAM_CFG_32_BE)
+				| SDRAM_CFG_DBW_32)
 				/* 0x43080000 */
 
 #define CONFIG_SYS_DDR_SDRAM_CFG2	0x00401000 /* 1 posted refresh */
diff --git a/include/configs/ve8313.h b/include/configs/ve8313.h
index f657610..69f29c7 100644
--- a/include/configs/ve8313.h
+++ b/include/configs/ve8313.h
@@ -81,7 +81,8 @@
 #define CONFIG_SYS_DDR_SIZE	128	/* MB */
 #define CONFIG_SYS_DDR_CONFIG	(CSCONFIG_EN \
 				| CSCONFIG_AP \
-				| 0x00040000 /* TODO */ \
+				| CSCONFIG_ODT_RD_NEVER \
+				| CSCONFIG_ODT_WR_ALL \
 				| CSCONFIG_ROW_BIT_13 \
 				| CSCONFIG_COL_BIT_10)
 				/* 0x80840102 */
@@ -118,7 +119,7 @@
 				/* 0x03202000 */
 #define CONFIG_SYS_SDRAM_CFG	(SDRAM_CFG_SREN \
 				| SDRAM_CFG_SDRAM_TYPE_DDR2 \
-				| SDRAM_CFG_32_BE)
+				| SDRAM_CFG_DBW_32)
 				/* 0x43080000 */
 #define CONFIG_SYS_SDRAM_CFG2	0x00401000
 #define CONFIG_SYS_DDR_MODE	((0x4440 << SDRAM_MODE_ESD_SHIFT) \
diff --git a/include/configs/vme8349.h b/include/configs/vme8349.h
index 19b4ad6..8e9b1f0 100644
--- a/include/configs/vme8349.h
+++ b/include/configs/vme8349.h
@@ -106,10 +106,13 @@
 #define CONFIG_SYS_DDR_BASE		0x00000000	/* DDR is sys memory*/
 #define CONFIG_SYS_SDRAM_BASE		CONFIG_SYS_DDR_BASE
 #define CONFIG_SYS_DDR_SDRAM_BASE	CONFIG_SYS_DDR_BASE
-#define CONFIG_SYS_DDR_SDRAM_CLK_CNTL	(DDR_SDRAM_CLK_CNTL_SS_EN | \
-					 DDR_SDRAM_CLK_CNTL_CLK_ADJUST_075)
+#define CONFIG_SYS_DDR_SDRAM_CLK_CNTL	(DDR_SDRAM_CLK_CNTL_SS_EN \
+					| DDR_SDRAM_CLK_CNTL_CLK_ADJUST_075)
 #define CONFIG_DDR_2T_TIMING
-#define CONFIG_SYS_DDRCDR		0x80080001
+#define CONFIG_SYS_DDRCDR		(DDRCDR_DHC_EN \
+					| DDRCDR_ODT \
+					| DDRCDR_Q_DRN)
+					/* 0x80080001 */
 
 /*
  * FLASH on the Local Bus