New patch to review for coreboot: c5a14a9 support for setting the Memory DQ Drive Strength register in amdk8 raminit

[Florian Zumbiehl]

Florian Zumbiehl just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/382

-gerrit

commit c5a14a9500962628913ed77d52fe86b16d500b04
Author: Florian Zumbiehl 
Date:   Tue Nov 1 20:19:03 2011 +0100

support for setting the Memory DQ Drive Strength register in amdk8 raminit

Change-Id: Ic68c10b75bd0217540fb1f55dded1f9d7f5e8aea
    Signed-off-by: Florian Zumbiehl 
---
 src/northbridge/amd/amdk8/Kconfig   |    9 +++++++++
 src/northbridge/amd/amdk8/pre_f.h   |    6 ++++++
 src/northbridge/amd/amdk8/raminit.c |   21 +++++++++++++++++++++
 3 files changed, 36 insertions(+), 0 deletions(-)

diff --git a/src/northbridge/amd/amdk8/Kconfig b/src/northbridge/amd/amdk8/Kconfig
index 858041a..2b87b64 100644
--- a/src/northbridge/amd/amdk8/Kconfig
+++ b/src/northbridge/amd/amdk8/Kconfig
@@ -45,6 +45,15 @@ config HW_MEM_HOLE_SIZE_AUTO_INC
    bool
    default n

+config K8_DQ_DRIVE_STRENGTH_0
+	bool
+config K8_DQ_DRIVE_STRENGTH_15
+	bool
+config K8_DQ_DRIVE_STRENGTH_30
+	bool
+config K8_DQ_DRIVE_STRENGTH_50
+	bool
+
 config BOOTBLOCK_NORTHBRIDGE_INIT
         string
         default "northbridge/amd/amdk8/bootblock.c"
diff --git a/src/northbridge/amd/amdk8/pre_f.h b/src/northbridge/amd/amdk8/pre_f.h
index dae2d97..0d5f6fa 100644
--- a/src/northbridge/amd/amdk8/pre_f.h
+++ b/src/northbridge/amd/amdk8/pre_f.h
@@ -157,6 +157,12 @@
 #define	  DCH_RDPREAMBLE_BASE ((2<<1)+0) /* 2.0 ns */
 #define	  DCH_RDPREAMBLE_MIN  ((2<<1)+0) /* 2.0 ns */
 #define	  DCH_RDPREAMBLE_MAX  ((9<<1)+1) /* 9.5 ns */
+#define	 DCH_DQ_DRV_STRENGTH_SHIFT 13
+#define	 DCH_DQ_DRV_STRENGTH_MASK 3
+#define	  DCH_DQ_DRV_STRENGTH_0 0
+#define	  DCH_DQ_DRV_STRENGTH_15 1
+#define	  DCH_DQ_DRV_STRENGTH_30 2
+#define	  DCH_DQ_DRV_STRENGTH_50 3
 #define	 DCH_IDLE_LIMIT_SHIFT 16
 #define	 DCH_IDLE_LIMIT_MASK  0x7
 #define	  DCH_IDLE_LIMIT_0    0
diff --git a/src/northbridge/amd/amdk8/raminit.c b/src/northbridge/amd/amdk8/raminit.c
index 944517b..9fdda2a 100644
--- a/src/northbridge/amd/amdk8/raminit.c
+++ b/src/northbridge/amd/amdk8/raminit.c
@@ -2192,6 +2192,27 @@ static void sdram_set_spd_registers(const struct mem_controller *ctrl)
    	printk(BIOS_DEBUG, "No memory for this cpu\n");
    	return;
    }
+
+#if CONFIG_K8_DQ_DRIVE_STRENGTH_0 || CONFIG_K8_DQ_DRIVE_STRENGTH_15 || CONFIG_K8_DQ_DRIVE_STRENGTH_30 || CONFIG_K8_DQ_DRIVE_STRENGTH_50
+	if (!is_cpu_pre_e0()) {
+		uint32_t dch, strength;
+
+#if CONFIG_K8_DQ_DRIVE_STRENGTH_0
+		strength = DCH_DQ_DRV_STRENGTH_0;
+#elif CONFIG_K8_DQ_DRIVE_STRENGTH_15
+		strength = DCH_DQ_DRV_STRENGTH_15;
+#elif CONFIG_K8_DQ_DRIVE_STRENGTH_30
+		strength = DCH_DQ_DRV_STRENGTH_30;
+#elif CONFIG_K8_DQ_DRIVE_STRENGTH_50
+		strength = DCH_DQ_DRV_STRENGTH_50;
+#endif
+		dch = pci_read_config32(ctrl->f2, DRAM_CONFIG_HIGH);
+		dch &= ~(DCH_DQ_DRV_STRENGTH_MASK << DCH_DQ_DRV_STRENGTH_SHIFT);
+		dch |= strength << DCH_DQ_DRV_STRENGTH_SHIFT;
+		pci_write_config32(ctrl->f2, DRAM_CONFIG_HIGH, dch);
+	}
+#endif
+
    dimm_mask = spd_enable_2channels(ctrl, dimm_mask);
    if (dimm_mask < 0)
    	goto hw_spd_err;